WorldWideScience

Sample records for advanced analytical simulation

  1. Advances in analytical chemistry

    Science.gov (United States)

    Arendale, W. F.; Congo, Richard T.; Nielsen, Bruce J.

    1991-01-01

    Implementation of computer programs based on multivariate statistical algorithms makes possible obtaining reliable information from long data vectors that contain large amounts of extraneous information, for example, noise and/or analytes that we do not wish to control. Three examples are described. Each of these applications requires the use of techniques characteristic of modern analytical chemistry. The first example, using a quantitative or analytical model, describes the determination of the acid dissociation constant for 2,2'-pyridyl thiophene using archived data. The second example describes an investigation to determine the active biocidal species of iodine in aqueous solutions. The third example is taken from a research program directed toward advanced fiber-optic chemical sensors. The second and third examples require heuristic or empirical models.

  2. Demonstration of structural performance of IP-2 packages by advanced analytical simulation and full-scale drop test

    International Nuclear Information System (INIS)

    Two new types of IP-2 (Industrial Package Type 2) to transport low and intermediate level radioactive waste (LILW) steel drums from nuclear power plants to a disposal facility have been developed in accordance with the IAEA and Korean regulations for radioactive materials. According to the regulations, both packages must preserve their structural performance after they are subjected to 0.9 m free drop tests, which are prescribed as normal conditions. In this study, an advanced analytical simulation and an evaluation process using the finite element (FE) method have been developed for the design assessment of the newly developed IP-2s. Then, analytical simulations for the various drop orientations were performed to evaluate the structural performance of the packages and demonstrate their compliance with the regulatory requirements. Also, full-scale drop tests were carried out to verify the numerical tools and modeling methodology used in the analyses and to confirm the performance of the IP-2s. In addition, parametric studies are carried out to investigate the sensitivity of the analytical variables, such as the material model and modeling methodology. In addition, this paper intends to provide basic guidance on the analytical simulation and evaluation process specifically for Korean types of transport packages, because numerous transport packages must now be developed for the various kinds of LILW that have accumulated in temporary storage facilities in Korea.

  3. Advanced analytical techniques

    International Nuclear Information System (INIS)

    The development of several new analytical techniques for use in clinical diagnosis and biomedical research is reported. These include: high-resolution liquid chromatographic systems for the early detection of pathological molecular constituents in physiologic body fluids; gradient elution chromatography for the analysis of protein-bound carbohydrates in blood serum samples, with emphasis on changes in sera from breast cancer patients; electrophoretic separation techniques coupled with staining of specific proteins in cellular isoenzymes for the monitoring of genetic mutations and abnormal molecular constituents in blood samples; and the development of a centrifugal elution chromatographic technique for the assay of specific proteins and immunoglobulins in human blood serum samples

  4. Leveraging data analytics, patterning simulations and metrology models to enhance CD metrology accuracy for advanced IC nodes

    Science.gov (United States)

    Rana, Narender; Zhang, Yunlin; Kagalwala, Taher; Hu, Lin; Bailey, Todd

    2014-04-01

    Integrated Circuit (IC) technology is changing in multiple ways: 193i to EUV exposure, planar to non-planar device architecture, from single exposure lithography to multiple exposure and DSA patterning etc. Critical dimension (CD) control requirement is becoming stringent and more exhaustive: CD and process window are shrinking., three sigma CD control of patterning. The accuracy of CD-AFM is ~1 nm and precision in TEM is poor due to limited statistics. CD-SEM, scatterometry and MBIR need to be calibrated by reference measurements for ensuring the accuracy of patterned CDs and patterning models. There is a dire need of measurement with patterning simulation and metrology models, and data integration techniques to selected applications demonstrating the potential solution and practicality of such an approach to enhance CD metrology accuracy. Data from multiple metrology techniques has been analyzed in multiple ways to extract information with associated uncertainties and integrated to extract the useful and more accurate CD and profile information of the structures. This paper presents the optimization of scatterometry and MBIR model calibration and feasibility to extrapolate not only in design and process space but from one process step to a previous process step. Well calibrated scatterometry model or patterning simulation model can be used to accurately extrapolate and interpolate in the design and process space for lithography patterning where AFM is not capable to accurately measure sub-40 nm trenches. Uncertainty associated with extrapolation can be large and needs to be minimized. We have made use of measurements from CD-SEM and CD-AFM, along with the patterning and scatterometry simulation models to estimate the uncertainty associated with extrapolation and methods to reduce it. First time we have reported the application of machine learning (Artificial Neural Networks) to the resist shrinkage systematic phenomenon to accurately predict the preshrink CD

  5. Advances in multiple analyte profiling.

    Science.gov (United States)

    Salas, Virginia M; Edwards, Bruce S; Sklar, Larry A

    2008-01-01

    The advent of multiparameter technology has been driven by the need to understand the complexity in biological systems. It has spawned two main branches, one in the arena of high-content measurements, primarily in microscopy and flow cytometry where it has become commonplace to analyze multiple fluorescence signatures arising from multiple excitation sources and multiple emission wavelengths. Microscopy is augmented by topographical content that identifies the source location of the signature. The other branch involves multiplex technology. Here, the intent is to measure multiple analytes simultaneously. A key feature of multiplexing is an address system for the individual analytes. In planar arrays the address system is spatial, in which affinity reactions occur at defined locations. In suspension arrays, the address is encoded as a fluorescent signature in the particle assigned to a specific reaction or analyte. Several hybrid systems have also been developed for multiplexing. In the commercial regime, the most widespread applications of multiplexing are currently in the areas of genome and biomarker analysis. Planar chips with fixed arrays are now available to probe the entire genome at the level of message expression and large segments of the genome at the level of single nucleotide polymorphism (SNP). In contrast, suspension arrays provide the potential for probing segments of the genome in a customized way, using capture tags that locate specific oligonucleotide sequences to specific array elements. PMID:18429493

  6. Making advanced analytics work for you.

    Science.gov (United States)

    Barton, Dominic; Court, David

    2012-10-01

    Senior leaders who write off the move toward big data as a lot of big talk are making, well, a big mistake. So argue McKinsey's Barton and Court, who worked with dozens of companies to figure out how to translate advanced analytics into nuts-and-bolts practices that affect daily operations on the front lines. The authors offer a useful guide for leaders and managers who want to take a deliberative approach to big data-but who also want to get started now. First, companies must identify the right data for their business, seek to acquire the information creatively from diverse sources, and secure the necessary IT support. Second, they need to build analytics models that are tightly focused on improving performance, making the models only as complex as business goals demand. Third, and most important, companies must transform their capabilities and culture so that the analytical results can be implemented from the C-suite to the front lines. That means developing simple tools that everyone in the organization can understand and teaching people why the data really matter. Embracing big data is as much about changing mind-sets as it is about crunching numbers. Executed with the right care and flexibility, this cultural shift could have payoffs that are, well, bigger than you expect. PMID:23074867

  7. Towards advanced code simulators

    International Nuclear Information System (INIS)

    The Central Electricity Generating Board (CEGB) uses advanced thermohydraulic codes extensively to support PWR safety analyses. A system has been developed to allow fully interactive execution of any code with graphical simulation of the operator desk and mimic display. The system operates in a virtual machine environment, with the thermohydraulic code executing in one virtual machine, communicating via interrupts with any number of other virtual machines each running other programs and graphics drivers. The driver code itself does not have to be modified from its normal batch form. Shortly following the release of RELAP5 MOD1 in IBM compatible form in 1983, this code was used as the driver for this system. When RELAP5 MOD2 became available, it was adopted with no changes needed in the basic system. Overall the system has been used for some 5 years for the analysis of LOBI tests, full scale plant studies and for simple what-if studies. For gaining rapid understanding of system dependencies it has proved invaluable. The graphical mimic system, being independent of the driver code, has also been used with other codes to study core rewetting, to replay results obtained from batch jobs on a CRAY2 computer system and to display suitably processed experimental results from the LOBI facility to aid interpretation. For the above work real-time execution was not necessary. Current work now centers on implementing the RELAP 5 code on a true parallel architecture machine. Marconi Simulation have been contracted to investigate the feasibility of using upwards of 100 processors, each capable of a peak of 30 MIPS to run a highly detailed RELAP5 model in real time, complete with specially written 3D core neutronics and balance of plant models. This paper describes the experience of using RELAP5 as an analyzer/simulator, and outlines the proposed methods and problems associated with parallel execution of RELAP5

  8. An analytical simulator for drillstem test interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Hegeman, P.; Abbaszadeh, M.

    1988-12-01

    An analytical drillstem test (DST) simulator has been developed that can be used to verify the interpretation of DST's that have insufficient or poor-quality flow-rate data. The DST is modeled as a sequence of alternating pressure-specified buildup periods. With field data, it is shown that this simulator can be used to enhance the interpretation of nonsurface flowing DST's.

  9. Advanced web metrics with Google Analytics

    CERN Document Server

    Clifton, Brian

    2012-01-01

    Get the latest information about using the #1 web analytics tool from this fully updated guide Google Analytics is the free tool used by millions of web site owners to assess the effectiveness of their efforts. Its revised interface and new features will offer even more ways to increase the value of your web site, and this book will teach you how to use each one to best advantage. Featuring new content based on reader and client requests, the book helps you implement new methods and concepts, track social and mobile visitors, use the new multichannel funnel reporting features, understand which

  10. Course on Advanced Analytical Chemistry and Chromatography

    DEFF Research Database (Denmark)

    Andersen, Jens Enevold Thaulov; Fristrup, Peter; Nielsen, Kristian Fog;

    2011-01-01

    Methods of analytical chemistry constitute an integral part of decision making in chemical research, and students must master a high degree of knowledge, in order to perform reliable analysis. At DTU departments of chemistry it was thus decided to develop a course that was attractive to master...... students of different direction of studies, to Ph.D. students and to professionals that need an update of their current state of skills and knowledge. A course of 10 ECTS points was devised with the purpose of introducing students to analytical chemistry and chromatography with the aim of including theory...

  11. Analytical advances in pharmaceutical impurity profiling.

    Science.gov (United States)

    Holm, René; Elder, David P

    2016-05-25

    Impurities will be present in all drug substances and drug products, i.e. nothing is 100% pure if one looks in enough depth. The current regulatory guidance on impurities accepts this, and for drug products with a dose of less than 2g/day identification of impurities is set at 0.1% levels and above (ICH Q3B(R2), 2006). For some impurities, this is a simple undertaking as generally available analytical techniques can address the prevailing analytical challenges; whereas, for others this may be much more challenging requiring more sophisticated analytical approaches. The present review provides an insight into current development of analytical techniques to investigate and quantify impurities in drug substances and drug products providing discussion of progress particular within the field of chromatography to ensure separation of and quantification of those related impurities. Further, a section is devoted to the identification of classical impurities, but in addition, inorganic (metal residues) and solid state impurities are also discussed. Risk control strategies for pharmaceutical impurities aligned with several of the ICH guidelines, are also discussed. PMID:26690047

  12. Advanced Analytics in Retail Banking in the Czech Republic

    OpenAIRE

    Búza, Ján

    2014-01-01

    Advanced analytics and big data allow a more complete picture of customers' preferences and demands. Through this deeper understanding, organizations of all types are finding new ways to engage with existing or potential customers. Research shows that companies using big data and advanced analytics in their operations have productivity and profitability rates that are 5 to 6 percent higher compared to their peers. At the same time it is almost impossible to find a banking institution in the C...

  13. Analytical chemistry requirements for advanced reactors

    International Nuclear Information System (INIS)

    The nuclear power industry has been developing and improving reactor technology for more than five decades. Newer advanced reactors now being built have simpler designs which reduce capital cost. The greatest departure from most designs now in operation is that many incorporate passive or inherent safety features which require no active controls or operational intervention to avoid accidents in the event of malfunction, and may rely on gravity, natural convection or resistance to high temperatures. India is developing the Advanced Heavy Water Reactor (AHWR) in its plan to utilise thorium in nuclear power program

  14. Recent Advances in Portable Analytical Electromigration Devices

    Directory of Open Access Journals (Sweden)

    Ann Van Schepdael

    2016-01-01

    Full Text Available This article presents an overview of recent advances in the field of portable capillary electrophoresis and microchip electrophoresis equipment during the period 2013–Mid 2015. Instrumental achievements in the separation as well as the detection part of the equipment are discussed. Several applications from a variety of fields are described.

  15. Analytical simulation of boiling water reactor pressure suppression pool swell

    International Nuclear Information System (INIS)

    In a loss-of-coolant accident, the pressure suppression pool of a boiling water reactor swells as a steam/air mixture is expelled from the drywell into the pool and large gas bubbles are formed beneath the surface. Many tests have been performed to quantify pool swell loads, but analytical methods have been limited in their ability to provide accurate loading estimates. With advancement of numerical methods, it is now feasible to numerically simulate the pool swell process. A finite difference solution algorithm is used to solve the transient imcompressible equations for the liquid flow field. Boundary conditions at the fluid-gas interface are determined using a simplified gas flow model. The program is used to simulate several pool swell tests: comparison of the simulation with test data shows good agreement

  16. Analytical simulation of boiling water reactor pressure suppression pool swell

    Energy Technology Data Exchange (ETDEWEB)

    Widener, S.K.

    1986-01-01

    In a loss-of-coolant accident, the pressure suppression pool of a boiling water reactor swells as a steam/air mixture is expelled from the drywell into the pool and large gas bubbles are formed beneath the surface. Many tests have been performed to quantify pool swell loads, but analytical methods have been limited in their ability to provide accurate loading estimates. With advancement of numerical methods, it is now feasible to numerically simulate the pool swell process. A finite difference solution algorithm is used to solve the transient imcompressible equations for the liquid flow field. Boundary conditions at the fluid-gas interface are determined using a simplified gas flow model. The program is used to simulate several pool swell tests: comparison of the simulation with test data shows good agreement.

  17. Analytical Aerodynamic Simulation Tools for Vertical Axis Wind Turbines

    International Nuclear Information System (INIS)

    Wind power is a renewable energy source that is today the fastest growing solution to reduce CO2 emissions in the electric energy mix. Upwind horizontal axis wind turbine with three blades has been the preferred technical choice for more than two decades. This horizontal axis concept is today widely leading the market. The current PhD thesis will cover an alternative type of wind turbine with straight blades and rotating along the vertical axis. A brief overview of the main differences between the horizontal and vertical axis concept has been made. However the main focus of this thesis is the aerodynamics of the wind turbine blades. Making aerodynamically efficient turbines starts with efficient blades. Making efficient blades requires a good understanding of the physical phenomena and effective simulations tools to model them. The specific aerodynamics for straight bladed vertical axis turbine flow are reviewed together with the standard aerodynamic simulations tools that have been used in the past by blade and rotor designer. A reasonably fast (regarding computer power) and accurate (regarding comparison with experimental results) simulation method was still lacking in the field prior to the current work. This thesis aims at designing such a method. Analytical methods can be used to model complex flow if the geometry is simple. Therefore, a conformal mapping method is derived to transform any set of section into a set of standard circles. Then analytical procedures are generalized to simulate moving multibody sections in the complex vertical flows and forces experienced by the blades. Finally the fast semi analytical aerodynamic algorithm boosted by fast multipole methods to handle high number of vortices is coupled with a simple structural model of the rotor to investigate potential aeroelastic instabilities. Together with these advanced simulation tools, a standard double multiple streamtube model has been developed and used to design several straight bladed

  18. Advanced Dynamics Analytical and Numerical Calculations with MATLAB

    CERN Document Server

    Marghitu, Dan B

    2012-01-01

    Advanced Dynamics: Analytical and Numerical Calculations with MATLAB provides a thorough, rigorous presentation of kinematics and dynamics while using MATLAB as an integrated tool to solve problems. Topics presented are explained thoroughly and directly, allowing fundamental principles to emerge through applications from areas such as multibody systems, robotics, spacecraft and design of complex mechanical devices. This book differs from others in that it uses symbolic MATLAB for both theory and applications. Special attention is given to solutions that are solved analytically and numerically using MATLAB. The illustrations and figures generated with MATLAB reinforce visual learning while an abundance of examples offer additional support. This book also: Provides solutions analytically and numerically using MATLAB Illustrations and graphs generated with MATLAB reinforce visual learning for students as they study Covers modern technical advancements in areas like multibody systems, robotics, spacecraft and des...

  19. Advanced numerical simulations of selected metallurgical units

    Directory of Open Access Journals (Sweden)

    G. Kokot

    2012-12-01

    Full Text Available Purpose: of this paper is to present numerical simulations of large structures in metallurgical industry. Some examples of finite element analysis are presented. The calculations were performed for the determining the stress effort of the metallurgical units mainly blast furnace, throath’s gas pipelines, hot blast stoves, etc. during the working conditions and for the repairing purpose.Design/methodology/approach: The way of conducting simulations and analysis were the finite element method connected with the optimization process.Findings: Performing the numerical analysis the changes in the structures design were applied what extremely influenced on the state effort and the durability of considered structures.Research limitations/implications: Development of the presented approach solving the coupled field and CFD problems, the application of the parallel computing and domain decomposition methods in the large structure simulations.Practical implications: Presented results shows the possibility of application the advanced computational methods in the computer aided engineering processes of designing and analysing the large structure as the metallurgical units are. It can dramatically influence on the recognizing of the effort stets and helps in the monitoring, overhauls and redesigning process. Those methods gives the global very precise information which cannot be obtain in other ways (analytical solutions, experimental methods.Originality/value: The paper present the original research results comes from the complex numerical simulations of the main metallurgical units in the blast furnace train. The original value of the paper is the introduction of the advanced finite element simulation in the field of iron steel industry structures design and developing.

  20. Interactive Simulations and advanced Visualization with Modelica

    OpenAIRE

    Bellmann, Tobias

    2009-01-01

    In this paper a Modelica library for interactive simulation and advanced visualization called ExternalDevices is introduced and presented. Providing support for standard input devices like keyboard and joystick as well as for communication via UDP and shared memory, this library allows the user to interact with a running simulation and process the output data of the simulation in other processes capable of UDP connections. An advanced visualization system replaces t...

  1. Advanced analytical techniques for boiling water reactor chemistry control

    International Nuclear Information System (INIS)

    The analytical techniques applied can be divided into 5 classes: OFF-LINE (discontinuous, central lab), AT-LINE (discontinuous, analysis near loop), ON-LINE (continuous, analysis in bypass). In all cases pressure and temperature of the water sample are reduced. In a strict sense only IN-LINE (continuous, flow disturbance) and NON-INVASIVE (continuous, no flow disturbance) techniques are suitable for direct process control; - the ultimate goal. An overview of the analytical techniques tested in the pilot loop is given. Apart from process and overall water quality control, standard for BWR operation, the main emphasis is on water impurity characterization (crud particles, hot filtration, organic carbon); on stress corrosion crackling control for materials (corrosion potential, oxygen concentration) and on the characterization of the oxide layer on austenites (impedance spectroscopy, IR-reflection). The above mentioned examples of advanced analytical techniques have the potential of in-line or non-invasive application. They are different stages of development and are described in more detail. 28 refs, 1 fig., 5 tabs

  2. Advances in analytical technologies for environmental protection and public safety.

    Science.gov (United States)

    Sadik, O A; Wanekaya, A K; Andreescu, S

    2004-06-01

    Due to the increased threats of chemical and biological agents of injury by terrorist organizations, a significant effort is underway to develop tools that can be used to detect and effectively combat chemical and biochemical toxins. In addition to the right mix of policies and training of medical personnel on how to recognize symptoms of biochemical warfare agents, the major success in combating terrorism still lies in the prevention, early detection and the efficient and timely response using reliable analytical technologies and powerful therapies for minimizing the effects in the event of an attack. The public and regulatory agencies expect reliable methodologies and devices for public security. Today's systems are too bulky or slow to meet the "detect-to-warn" needs for first responders such as soldiers and medical personnel. This paper presents the challenges in monitoring technologies for warfare agents and other toxins. It provides an overview of how advances in environmental analytical methodologies could be adapted to design reliable sensors for public safety and environmental surveillance. The paths to designing sensors that meet the needs of today's measurement challenges are analyzed using examples of novel sensors, autonomous cell-based toxicity monitoring, 'Lab-on-a-Chip' devices and conventional environmental analytical techniques. Finally, in order to ensure that the public and legal authorities are provided with quality data to make informed decisions, guidelines are provided for assessing data quality and quality assurance using the United States Environmental Protection Agency (US-EPA) methodologies. PMID:15173903

  3. Advanced circuit simulation using Multisim workbench

    CERN Document Server

    Báez-López, David; Cervantes-Villagómez, Ofelia Delfina

    2012-01-01

    Multisim is now the de facto standard for circuit simulation. It is a SPICE-based circuit simulator which combines analog, discrete-time, and mixed-mode circuits. In addition, it is the only simulator which incorporates microcontroller simulation in the same environment. It also includes a tool for printed circuit board design.Advanced Circuit Simulation Using Multisim Workbench is a companion book to Circuit Analysis Using Multisim, published by Morgan & Claypool in 2011. This new book covers advanced analyses and the creation of models and subcircuits. It also includes coverage of transmissi

  4. Simulation-analytic model of a distributed informational system

    International Nuclear Information System (INIS)

    A model for the choice of effective connection channels between elements of a distributed homomorphous network has been described. This model combines simulation and analytical approaches in its architecture. Arguments for using such complex models, examples of some simulation results for a system with distributed topology have been given and summarized conclusions have been made

  5. The use of advanced computer simulation in structural design

    Energy Technology Data Exchange (ETDEWEB)

    Field, C.J.; Mole, A. [Arup, San Fransisco, CA (United States); Arkinstall, M. [Arup, Sydney (Australia)

    2005-07-01

    The benefits that can be gained from the application of advanced numerical simulation in building design were discussed. A review of current practices in structural engineering was presented along with an illustration of a range of international project case studies. Structural engineers use analytical methods to evaluate both static and dynamic loads. Structural design is prescribed by a range of building codes, depending on location, building type and loading, but often, buildings do not fit well within the codes, particularly if one wants to take advantage of new technologies and developments in design that are not covered by the code. Advanced simulation refers to the use of mathematical modeling to complex problems to allow a wider consideration of building types and conditions that can be designed reliably using standard practices. Advanced simulation is used to address virtual testing and prototyping, verifying innovative design ideas, forensic engineering, and design optimization. The benefits of advanced simulation include enhanced creativity, improved performance, cost savings, risk management, sustainable design solutions, and better communication. The following 5 case studies illustrated the value gained by using advanced simulation as an integral part of the design process: the earthquake resistant Maison Hermes in Tokyo; the seismic resistant braces known as the Unbonded Brace for use in the United States; a simulation of the existing Disney Museum to evaluate its capacity to resist earthquakes; simulation of the MIT Brain and Cognitive Science Project to evaluate the effect of different foundation types on the vibration entering the building; and, the Beijing Aquatic Center whose design was streamlined by optimized structural analysis. It was suggested that industry should encourage the transfer of technology from other professions and should try to collaborate towards a global building model to construct buildings in a more efficient manner. 7 refs

  6. INFIL1D: a quasi-analytical model for simulating one-dimensional, constant flux infiltration

    International Nuclear Information System (INIS)

    The program INFIL1D is designed to calculate approximate wetting-front advance into an unsaturated, uniformly moist, homogeneous soil profile, under constant surface-flux conditions. The code is based on a quasi-analytical method, which utilizes an assumed invariant functional relationship between reduced (normalized) flux and water content. The code uses general hydraulic property data in tabular form to simulate constant surface-flux infiltration. 10 references, 4 figures

  7. Advanced Vadose Zone Simulations Using TOUGH

    Energy Technology Data Exchange (ETDEWEB)

    Finsterle, S.; Doughty, C.; Kowalsky, M.B.; Moridis, G.J.; Pan,L.; Xu, T.; Zhang, Y.; Pruess, K.

    2007-02-01

    The vadose zone can be characterized as a complex subsurfacesystem in which intricate physical and biogeochemical processes occur inresponse to a variety of natural forcings and human activities. Thismakes it difficult to describe, understand, and predict the behavior ofthis specific subsurface system. The TOUGH nonisothermal multiphase flowsimulators are well-suited to perform advanced vadose zone studies. Theconceptual models underlying the TOUGH simulators are capable ofrepresenting features specific to the vadose zone, and of addressing avariety of coupled phenomena. Moreover, the simulators are integratedinto software tools that enable advanced data analysis, optimization, andsystem-level modeling. We discuss fundamental and computationalchallenges in simulating vadose zone processes, review recent advances inmodeling such systems, and demonstrate some capabilities of the TOUGHsuite of codes using illustrative examples.

  8. Advances in Intelligent Modelling and Simulation Simulation Tools and Applications

    CERN Document Server

    Oplatková, Zuzana; Carvalho, Marco; Kisiel-Dorohinicki, Marek

    2012-01-01

    The human capacity to abstract complex systems and phenomena into simplified models has played a critical role in the rapid evolution of our modern industrial processes and scientific research. As a science and an art, Modelling and Simulation have been one of the core enablers of this remarkable human trace, and have become a topic of great importance for researchers and practitioners. This book was created to compile some of the most recent concepts, advances, challenges and ideas associated with Intelligent Modelling and Simulation frameworks, tools and applications. The first chapter discusses the important aspects of a human interaction and the correct interpretation of results during simulations. The second chapter gets to the heart of the analysis of entrepreneurship by means of agent-based modelling and simulations. The following three chapters bring together the central theme of simulation frameworks, first describing an agent-based simulation framework, then a simulator for electrical machines, and...

  9. A parsimonious analytical model for simulating multispecies plume migration

    Science.gov (United States)

    Chen, J.-S.; Liang, C.-P.; Liu, C.-W.; Li, L. Y.

    2015-09-01

    A parsimonious analytical model for rapidly predicting the long-term plume behavior of decaying contaminant such as radionuclide and dissolved chlorinated solvent is presented in this study. Generalized analytical solutions in compact format are derived for the two-dimensional advection-dispersion equations coupled with sequential first-order decay reactions involving an arbitrary number of species in groundwater system. The solution techniques involve the sequential applications of the Laplace, finite Fourier cosine, and generalized integral transforms to reduce the coupled partial differential equation system to a set of linear algebraic equations. The system of algebraic equations is next solved for each species in the transformed domain, and the solutions in the original domain are then obtained through consecutive integral transform inversions. Explicit form solutions for a special case are derived using the generalized analytical solutions and are verified against the numerical solutions. The analytical results indicate that the parsimonious analytical solutions are robust and accurate. The solutions are useful for serving as simulation or screening tools for assessing plume behaviors of decaying contaminants including the radionuclides and dissolved chlorinated solvents in groundwater systems.

  10. Advancing Analytical Methods for Characterization of Anionic Carbohydrate Biopolymers

    OpenAIRE

    Langeslay, Derek Joseph

    2013-01-01

    The focus of this dissertation is on the development of improved analytical methods for the characterization of anionic carbohydrate biopolymers. Our goal is to extract important information from complex mixtures of heterogeneous polysaccharides by characterizing their substituent oligosaccharides in terms of monosaccharide composition and primary and secondary structure. This work focuses on the application of two major analytical platforms: spectroscopy and chromatography. The development ...

  11. Analytical simulation platform describing projections in computed tomography systems

    Energy Technology Data Exchange (ETDEWEB)

    Youn, Hanbean; Kim, Ho Kyung [Pusan National Univ., Busan (Korea, Republic of)

    2013-10-15

    To reduce the patient dose, several approaches such as spectral imaging using photon counting detectors and statistical image reconstruction, are being considered. Although image-reconstruction algorithms may significantly enhance image quality in reconstructed images with low dose, true signal-to-noise properties are mainly determined by image quality in projections. We are developing an analytical simulation platform describing projections to investigate how quantum-interaction physics in each component configuring CT systems affect image quality in projections. This simulator will be very useful for an improved design or optimization of CT systems in economy as well as the development of novel image-reconstruction algorithms. In this study, we present the progress of development of the simulation platform with an emphasis on the theoretical framework describing the generation of projection data. We have prepared the analytical simulation platform describing projections in computed tomography systems. The remained further study before the meeting includes the following: Each stage in the cascaded signal-transfer model for obtaining projections will be validated by the Monte Carlo simulations. We will build up energy-dependent scatter and pixel-crosstalk kernels, and show their effects on image quality in projections and reconstructed images. We will investigate the effects of projections obtained from various imaging conditions and system (or detector) operation parameters on reconstructed images. It is challenging to include the interaction physics due to photon-counting detectors into the simulation platform. Detailed descriptions of the simulator will be presented with discussions on its performance and limitation as well as Monte Carlo validations. Computational cost will also be addressed in detail. The proposed method in this study is simple and can be used conveniently in lab environment.

  12. Dynamic Simulations of Advanced Fuel Cycles

    Energy Technology Data Exchange (ETDEWEB)

    Steven J. Piet; Brent W. Dixon; Jacob J. Jacobson; Gretchen E. Matthern; David E. Shropshire

    2011-03-01

    Years of performing dynamic simulations of advanced nuclear fuel cycle options provide insights into how they could work and how one might transition from the current once-through fuel cycle. This paper summarizes those insights from the context of the 2005 objectives and goals of the U.S. Advanced Fuel Cycle Initiative (AFCI). Our intent is not to compare options, assess options versus those objectives and goals, nor recommend changes to those objectives and goals. Rather, we organize what we have learned from dynamic simulations in the context of the AFCI objectives for waste management, proliferation resistance, uranium utilization, and economics. Thus, we do not merely describe “lessons learned” from dynamic simulations but attempt to answer the “so what” question by using this context. The analyses have been performed using the Verifiable Fuel Cycle Simulation of Nuclear Fuel Cycle Dynamics (VISION). We observe that the 2005 objectives and goals do not address many of the inherently dynamic discriminators among advanced fuel cycle options and transitions thereof.

  13. Universal analytic model for tunnel FET circuit simulation

    Science.gov (United States)

    Lu, Hao; Esseni, David; Seabaugh, Alan

    2015-06-01

    A simple analytic model based on the Kane-Sze formula is used to describe the current-voltage characteristics of tunnel field-effect transistors (TFETs). This model captures the unique features of the TFET including the decrease in subthreshold swing with drain current and the superlinear onset of the output characteristic. The model also captures the ambipolar current characteristic at negative gate-source bias and the negative differential resistance for negative drain-source biases. A simple empirical capacitance model is also included to enable circuit simulation. The model has fairly general validity and is not specific to a particular TFET geometry. Good agreement is shown with published atomistic simulations of an InAs double-gate TFET with gate perpendicular to the tunnel junction and with numerical simulations of a broken-gap AlGaSb/InAs TFET with gate in parallel with the tunnel junction.

  14. 14 CFR Appendix H to Part 121 - Advanced Simulation

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Advanced Simulation H Appendix H to Part... Simulation This appendix provides guidelines and a means for achieving flightcrew training in advanced... simulator, as appropriate. Advanced Simulation Training Program For an operator to conduct Level C or...

  15. Impact analytical models for earthquake-induced pounding simulation

    Institute of Scientific and Technical Information of China (English)

    Kun YE; Li LI

    2009-01-01

    Structural pounding under earthquake has been recently extensively investigated using various impact analytical models. In this paper, a brief review on the commonly used impact analytical models is conducted.Based on this review, the formula used to determine the damping constant related to the impact spring stiffness,coefficient of restitution, and relative approaching velocity in the Hertz model with nonlinear damping is found to be incorrect. To correct this error, a more accurate approximating formula for the damping constant is theoretically derived 5~nd numerically verified. At the same time, a modified Kelvin impact model, which can reasonably account for the physical nature of pounding and conveniently implemented in the earthquake-induced pounding simulation of structural engineering is proposed.

  16. Assessment of training simulators with advanced models

    International Nuclear Information System (INIS)

    Training quality received by the nuclear power plants operators is related to the reliability degree reached by the models which constitute the calculation basis. TECNATOM began, in the middle of the 80's, the PWR and BWR training simulators upgrading to reproduce all type of transients with long term operation and a very high reliability degree. As a result of this, the Simulation Advanced Models Project (MAS) has been developed for both PWR and BWR simulators. The simulators software is the TRAC code running in real time on the CRAY X-MP 14 vectorial computer. The validation methodology followed in the MAS Project is based on the EPRI's one. The main goal is the detailed analysis of the variables and physical phenomena to validate ('dynamic modes') included in the validation transients matrix. The reference results are supplied by plant data or best estimate codes: TRAC-PF1/MOD1 and TRACG for PWR and BWR training simulators, respectively. This paper shows the main results of validation transients and the main conclusions: improvement of simulation scope and reliability, EOP's scenarios simulation with long term recovery and physical phenomena analysis similar to best estimate codes. (orig.) (13 refs., 17 figs., 4 tabs.)

  17. Advanced simulation for fast reactor design

    International Nuclear Information System (INIS)

    Full text: This talk broadly reviews recent research aimed at applying advanced simulation techniques specifically to fast neutron reactors. By advanced simulation we generally refer to attempts to do more science-based simulation - that is, to numerically solve the three-dimensional governing physical equations on fine scales and observe and study the holistic phenomena that emerge. In this way simulation is treated more akin to a traditional physical experiment, and can can be used both separately and in conjunction with physical experiments to develop more accurate predictive theories on reactor behavior. Many existing fast reactor modeling tools were developed for last generation's computational resources. They were built by engineers and physicists with deep physical insight - insight that both shaped and was informed by existing theory, and was underpinned by a vast repository of experimental data. Their general approach was to develop models that were tailored to varying degrees to the details of the reactor design, using free model parameters that were subsequently calibrated to match existing experimental data. The resulting codes were thus extremely useful for their specific purpose but highly limited in their predictive capability (neutronics to a lesser degree). They tended to represent more the state-of-the-art in our understanding rather than tools of exploration and innovation. Recently, a number of researchers have attempted to study the feasibility of solving more fundamental governing equations on realistic, three-dimensional geometries for different fast reactor sub-domains. This includes solving the Navier-Stokes equations for single-phase sodium flow (Direct Numerical Simulation, Large Eddie Simulation, and Reynolds Averaged Navier Stokes Equations) in the core, upper plenum, primary and intermediate loop, etc.; the non-homogenized transport equations at very fine group, angle, and energy discretization, and thermo-mechanical feedback based on

  18. Advanced ST plasma scenario simulations for NSTX

    International Nuclear Information System (INIS)

    Integrated scenario simulations are done for NSTX that address four primary milestones for developing advanced ST configurations: high β and high βN inductive discharges to study all aspects of ST physics in the high beta regime; non-inductively sustained discharges for flattop times greater than the skin time to study the various current drive techniques; non-inductively sustained discharges at high βfor flattop times much greater than a skin time which provides the integrated advanced ST target for NSTX; and non-solenoidal startup and plasma current rampup. The simulations done here use the Tokamak Simulation Code (TSC) and are based on a discharge 109070. TRANSP analysis of the discharge provided the thermal diffusivities for electrons and ions, the neutral beam (NB) deposition profile and other characteristics. CURRAY is used to calculate the High Harmonic Fast Wave (HHFW) heating depositions and current drive. GENRAY/CQL3D is used to establish the heating and CD deposition profiles for electron Bernstein waves (EBW). Analysis of the ideal MHD stability is done with JSOLVER, BALMSC, and PEST2. The simulations indicate that the integrated advanced ST plasma is reachable, obtaining stable plasmas with β ∼ 40% at βN's of 7.7-9, IP = 1.0 MA and BT = 0.35 T. The plasma is 100% non-inductive and has a flattop of 4 skin times. The resulting global energy confinement corresponds to a multiplier of H98(y,2) = 1.5. The simulations have demonstrated the importance of HHFW heating and CD, EBW off-axis CD, strong plasma shaping, density control, and early heating/H-mode transition for producing and optimizing these plasma configurations (author)

  19. Comparing Finesse simulations, analytical solutions and OSCAR simulations of Fabry-Perot alignment signals

    CERN Document Server

    Ballmer, Stefan; Freise, Andreas; Fulda, Paul

    2014-01-01

    This document records the results of a comparison of the interferometer simulation Finesse against an analytic (MATLAB based) calculation of the alignment sensing signals of a Fabry Perot cavity. This task was started during the commissioning workshop at the LIGO Livingston site between the 28.1. and 1.02 2013 with the aim of creating a reference example for validating numerical simulation tools. The FFT based simulation OSCAR joined the battle later.

  20. Big Data Visual Analytics for Exploratory Earth System Simulation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Steed, Chad A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ricciuto, Daniel M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Shipman, Galen M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Smith, Brian E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Thornton, Peter E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Dali [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Shi, Xiaoying [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Williams, Dean N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2013-12-01

    Rapid increases in high performance computing are feeding the development of larger and more complex data sets in climate research, which sets the stage for so-called big data analysis challenges. However, conventional climate analysis techniques are inadequate in dealing with the complexities of today s data. In this paper, we describe and demonstrate a visual analytics system, called the Exploratory Data analysis ENvironment (EDEN), with specific application to the analysis of complex earth system simulation data sets. EDEN represents the type of interactive visual analysis tools that are necessary to transform data into insight, thereby improving critical comprehension of earth system processes. In addition to providing an overview of EDEN, we describe real-world studies using both point ensembles and global Community Land Model Version 4 (CLM4) simulations.

  1. Analytic initialization method for xenon oscillation in power reactor simulation

    International Nuclear Information System (INIS)

    The purpose of simulating nuclear power reactor core transients is to predict variations in core behavior due to changes in operating conditions. In the simulation, the initial condition of the core transient should be consistent with the real core state. Especially, the initial conditions of iodine and xenon distributions, which cannot be measured in the core, have dominant effects on the accuracy of the simulation for the transients related with xenon dynamics. If the transient starts from non-equilibrium xenon condition, the accurate initialization of the non-equilibrium iodine and xenon distributions is essential for the prediction of the core transient behavior. In this study, a simple initialization method of non-equilibrium iodine and xenon distributions for the core transient simulation was developed using axial power difference, which is the only measurable parameter related with the non-equilibrium state of the core. For this purpose, the spatial distribution of two-group one-dimensional neutron diffusion equation combined with xenon dynamics equation was expanded with Fourier sine series. It was found that the nonlinearly combined terms of flux and xenon distributions in the equations were canceled by the orthogonal characteristics of the Fourier series using adequate approximation. Therefore, the dynamics equations for axial difference parameters of power, iodine and xenon can be completely linearized and can be converted into an equation system which can be solved analytically. Because the equation system provides with an analytic relationship between the axial differences of power, iodine and xenon, the non-equilibrium iodine and xenon can be represented as functions of the axial power difference. It implies that the initial condition of the transient starting from a non-equilibrium state can be determined from the initial condition of the axial power difference which is a measurable parameter of the core. Using the analytic solution obtained in this

  2. Motion control in advanced driving simulators

    OpenAIRE

    Elloumi, Hatem

    2006-01-01

    Driving simulators are advanced devices composed of four components: a virtual scene projected on a wide screen to imitate the road and the traffic, an audio system to play the driving sounds (horn, squeal of brakes, etc.), a car cockpit (including a real dashboard, the pedals and the seat of the driver) to copy the body position and the interaction of the driver with a real vehicle and finally a robot carrying the car cockpit to provide its motion. While the first three components could be c...

  3. Advances in Assays and Analytical Approaches for Botulinum Toxin Detection

    Energy Technology Data Exchange (ETDEWEB)

    Grate, Jay W.; Ozanich, Richard M.; Warner, Marvin G.; Bruckner-Lea, Cindy J.; Marks, James D.

    2010-08-04

    Methods to detect botulinum toxin, the most poisonous substance known, are reviewed. Current assays are being developed with two main objectives in mind: 1) to obtain sufficiently low detection limits to replace the mouse bioassay with an in vitro assay, and 2) to develop rapid assays for screening purposes that are as sensitive as possible while requiring an hour or less to process the sample an obtain the result. This review emphasizes the diverse analytical approaches and devices that have been developed over the last decade, while also briefly reviewing representative older immunoassays to provide background and context.

  4. Software Framework for Advanced Power Plant Simulations

    Energy Technology Data Exchange (ETDEWEB)

    John Widmann; Sorin Munteanu; Aseem Jain; Pankaj Gupta; Mark Moales; Erik Ferguson; Lewis Collins; David Sloan; Woodrow Fiveland; Yi-dong Lang; Larry Biegler; Michael Locke; Simon Lingard; Jay Yun

    2010-08-01

    This report summarizes the work accomplished during the Phase II development effort of the Advanced Process Engineering Co-Simulator (APECS). The objective of the project is to develop the tools to efficiently combine high-fidelity computational fluid dynamics (CFD) models with process modeling software. During the course of the project, a robust integration controller was developed that can be used in any CAPE-OPEN compliant process modeling environment. The controller mediates the exchange of information between the process modeling software and the CFD software. Several approaches to reducing the time disparity between CFD simulations and process modeling have been investigated and implemented. These include enabling the CFD models to be run on a remote cluster and enabling multiple CFD models to be run simultaneously. Furthermore, computationally fast reduced-order models (ROMs) have been developed that can be 'trained' using the results from CFD simulations and then used directly within flowsheets. Unit operation models (both CFD and ROMs) can be uploaded to a model database and shared between multiple users.

  5. Workplace Skills Taught in a Simulated Analytical Department

    Science.gov (United States)

    Sonchik Marine, Susan

    2001-11-01

    Integration of workplace skills into the academic setting is paramount for any chemical technology program. In addition to the expected chemistry content, courses must build proficiency in oral and written communication skills, computer skills, laboratory safety, and logical troubleshooting. Miami University's Chemical Technology II course is set up as a contract analytical laboratory. Students apply the advanced sampling techniques, quality assurance, standard methods, and statistical analyses they have studied. For further integration of workplace skills, weekly "department meetings" are held where the student, as members of the department, report on their work in process, present completed projects, and share what they have learned and what problems they have encountered. Information is shared between the experienced members of the department and those encountering problems or starting a new project. The instructor as department manager makes announcements, reviews company and department status, and assigns work for the coming week. The department members report results to clients in formal reports or in short memos. Factors affecting the success of the "department meeting" approach include the formality of the meeting room, use of an official agenda, the frequency, time, and duration of the meeting, and accountability of the students.

  6. Structural level characterization of base oils using advanced analytical techniques

    KAUST Repository

    Hourani, Nadim

    2015-05-21

    Base oils, blended for finished lubricant formulations, are classified by the American Petroleum Institute into five groups, viz., groups I-V. Groups I-III consist of petroleum based hydrocarbons whereas groups IV and V are made of synthetic polymers. In the present study, five base oil samples belonging to groups I and III were extensively characterized using high performance liquid chromatography (HPLC), comprehensive two-dimensional gas chromatography (GC×GC), and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) equipped with atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI) sources. First, the capabilities and limitations of each analytical technique were evaluated, and then the availed information was combined to reveal compositional details on the base oil samples studied. HPLC showed the overwhelming presence of saturated over aromatic compounds in all five base oils. A similar trend was further corroborated using GC×GC, which yielded semiquantitative information on the compound classes present in the samples and provided further details on the carbon number distributions within these classes. In addition to chromatography methods, FT-ICR MS supplemented the compositional information on the base oil samples by resolving the aromatics compounds into alkyl- and naphtheno-subtituted families. APCI proved more effective for the ionization of the highly saturated base oil components compared to APPI. Furthermore, for the detailed information on hydrocarbon molecules FT-ICR MS revealed the presence of saturated and aromatic sulfur species in all base oil samples. The results presented herein offer a unique perspective into the detailed molecular structure of base oils typically used to formulate lubricants. © 2015 American Chemical Society.

  7. Machine learning and cosmological simulations - I. Semi-analytical models

    Science.gov (United States)

    Kamdar, Harshil M.; Turk, Matthew J.; Brunner, Robert J.

    2016-01-01

    We present a new exploratory framework to model galaxy formation and evolution in a hierarchical Universe by using machine learning (ML). Our motivations are two-fold: (1) presenting a new, promising technique to study galaxy formation, and (2) quantitatively analysing the extent of the influence of dark matter halo properties on galaxies in the backdrop of semi-analytical models (SAMs). We use the influential Millennium Simulation and the corresponding Munich SAM to train and test various sophisticated ML algorithms (k-Nearest Neighbors, decision trees, random forests, and extremely randomized trees). By using only essential dark matter halo physical properties for haloes of M > 1012 M⊙ and a partial merger tree, our model predicts the hot gas mass, cold gas mass, bulge mass, total stellar mass, black hole mass and cooling radius at z = 0 for each central galaxy in a dark matter halo for the Millennium run. Our results provide a unique and powerful phenomenological framework to explore the galaxy-halo connection that is built upon SAMs and demonstrably place ML as a promising and a computationally efficient tool to study small-scale structure formation.

  8. Machine Learning and Cosmological Simulations I: Semi-Analytical Models

    CERN Document Server

    Kamdar, Harshil M; Brunner, Robert J

    2016-01-01

    We present a new exploratory framework to model galaxy formation and evolution in a hierarchical universe by using machine learning (ML). Our motivations are two-fold: (1) presenting a new, promising technique to study galaxy formation, and (2) quantitatively analyzing the extent of the influence of dark matter halo properties on galaxies in the backdrop of semi-analytical models (SAMs). We use the influential Millennium Simulation and the corresponding Munich SAM to train and test various sophisticated machine learning algorithms (k-Nearest Neighbors, decision trees, random forests and extremely randomized trees). By using only essential dark matter halo physical properties for haloes of $M>10^{12} M_{\\odot}$ and a partial merger tree, our model predicts the hot gas mass, cold gas mass, bulge mass, total stellar mass, black hole mass and cooling radius at z = 0 for each central galaxy in a dark matter halo for the Millennium run. Our results provide a unique and powerful phenomenological framework to explore...

  9. Characterization of organic photovoltaic cells in comparison with analytic simulations

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, Christian [Universitaet Wuerzburg (Germany). Experimentelle Physik VI; Universitaet Wuerzburg (Germany). Experimentelle Physik II; Holch, Florian; Schoell, Achim; Reinert, Friedrich [Universitaet Wuerzburg (Germany). Experimentelle Physik II; Deibel, Carsten; Dyakonov, Vladimir [Universitaet Wuerzburg (Germany). Experimentelle Physik VI

    2008-07-01

    Electronic devices based on organic semiconductors receive a growing interest in fundamental and application related research. One reason is that organic thin film photovoltaic cells promise to offer a cost- and resource-efficient fabrication. In order to achieve higher efficiencies it is indispensable to better understand the fundamental processes within the solar cell and at the interfaces, such as charge-carrier generation, separation and transport. The samples, composed of copper-phthalocyanine (CuPc) and C{sub 60} layers and sandwiched between an ITO-coated glass substrate and metal electrodes, are prepared via organic molecular beam deposition under clean and well defined conditions in ultra high vacuum. By in-situ measurements of the current-voltage characteristics, the influence of incident light power, temperature, and cathode material can be investigated in detail. The experimental results are discussed in comparison to an analytical simulation of the open-circuit voltage, in view of different models for the charge carrier injection at the electrodes.

  10. ARIANNE. Analytical uncertainties. Simulation of influential factors in the inventory of the final web cam

    International Nuclear Information System (INIS)

    Analysis of analytical uncertainties of the methodology of simulation of processes for obtaining isotopic ending inventory of spent fuel, the ARIANE experiment explores the part of simulation of burning.

  11. Understanding Fluorescence Measurements through a Guided-Inquiry and Discovery Experiment in Advanced Analytical Laboratory

    Science.gov (United States)

    Wilczek-Vera, Grazyna; Salin, Eric Dunbar

    2011-01-01

    An experiment on fluorescence spectroscopy suitable for an advanced analytical laboratory is presented. Its conceptual development used a combination of the expository and discovery styles. The "learn-as-you-go" and direct "hands-on" methodology applied ensures an active role for a student in the process of visualization and discovery of concepts.…

  12. A May American Economic Review Papers Seminar and an Analytic Project for Advanced Undergraduates

    Science.gov (United States)

    Elliott, Catherine S.

    2004-01-01

    The author describes two learning activities for teaching economics at the advanced undergraduate level: a May American Economic Review (AER) papers seminar and an analytic project. Both activities help students learn to "do economics." The May AER papers seminar promotes in-depth synthesis and interpretation on the basis of printed session papers…

  13. A Comprehensive Microfluidics Device Construction and Characterization Module for the Advanced Undergraduate Analytical Chemistry Laboratory

    Science.gov (United States)

    Piunno, Paul A. E.; Zetina, Adrian; Chu, Norman; Tavares, Anthony J.; Noor, M. Omair; Petryayeva, Eleonora; Uddayasankar, Uvaraj; Veglio, Andrew

    2014-01-01

    An advanced analytical chemistry undergraduate laboratory module on microfluidics that spans 4 weeks (4 h per week) is presented. The laboratory module focuses on comprehensive experiential learning of microfluidic device fabrication and the core characteristics of microfluidic devices as they pertain to fluid flow and the manipulation of samples.…

  14. TNO-ADVANCE: a modular powertrain simulation and design tool

    NARCIS (Netherlands)

    Venne, J.W.C. van de; Smokers, R.T.M.

    2000-01-01

    To support its activities in the field of conventional and hybrid vehicles, TNO has developed ADVANCE, a modular simulation tool for the design and evaluation of advanced powertrains. In this paper the various features and the potential of ADVANCE are described and illustrated by means of three case

  15. Advanced TCAD Simulations and Characterization of Semiconductor Devices

    OpenAIRE

    Ewert, Tony

    2006-01-01

    Today, micro- and nano-electronic devices are becoming more complex and advanced as the dimensions are shrinking. It is therefore a very challenging task to develop new device technologies with performance that can be predicted. This thesis focuses on advanced measurement techniques and TCAD simulations in order to characterize and understand the device physics of advanced semiconductor devices. TCAD simulations were made on a novel MOSFET device with asymmetric source and drain structures. ...

  16. Precision Casting via Advanced Simulation and Manufacturing

    Science.gov (United States)

    1997-01-01

    A two-year program was conducted to develop and commercially implement selected casting manufacturing technologies to enable significant reductions in the costs of castings, increase the complexity and dimensional accuracy of castings, and reduce the development times for delivery of high quality castings. The industry-led R&D project was cost shared with NASA's Aerospace Industry Technology Program (AITP). The Rocketdyne Division of Boeing North American, Inc. served as the team lead with participation from Lockheed Martin, Ford Motor Company, Howmet Corporation, PCC Airfoils, General Electric, UES, Inc., University of Alabama, Auburn University, Robinson, Inc., Aracor, and NASA-LeRC. The technical effort was organized into four distinct tasks. The accomplishments reported herein. Task 1.0 developed advanced simulation technology for core molding. Ford headed up this task. On this program, a specialized core machine was designed and built. Task 2.0 focused on intelligent process control for precision core molding. Howmet led this effort. The primary focus of these experimental efforts was to characterize the process parameters that have a strong impact on dimensional control issues of injection molded cores during their fabrication. Task 3.0 developed and applied rapid prototyping to produce near net shape castings. Rocketdyne was responsible for this task. CAD files were generated using reverse engineering, rapid prototype patterns were fabricated using SLS and SLA, and castings produced and evaluated. Task 4.0 was aimed at developing technology transfer. Rocketdyne coordinated this task. Casting related technology, explored and evaluated in the first three tasks of this program, was implemented into manufacturing processes.

  17. A parsimonious analytical model for simulating multispecies plume migration

    OpenAIRE

    J.-S. Chen; C.-P. Liang; C.-W. Liu; Li, L. Y.

    2015-01-01

    A parsimonious analytical model for rapidly predicting the long-term plume behavior of decaying contaminant such as radionuclide and dissolved chlorinated solvent is presented in this study. Generalized analytical solutions in compact format are derived for the two-dimensional advection-dispersion equations coupled with sequential first-order decay reactions involving an arbitrary number of species in groundwater system. The solution techniques involve the sequential applica...

  18. Analytical, numerical, and experimental simulation of tornado flows

    International Nuclear Information System (INIS)

    It has been proven that this problem with analytic input data near the point under consideration has a unique analytic solution representable in the form of a convergent series. The analysis of the first coefficients of this series has shown that the circular motion of the gas swirling in the positive direction in the Northern Hemisphere and in the negative direction in the Southern Hemisphere arises immediately at the beginning of the radial flow into the cylinder

  19. Simulation of advanced ultrasound systems using Field II

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    2004-01-01

    impulse responses is explained. A simulation example for a synthetic aperture spread spectrum flow systems is described. It is shown how the advanced coded excitation can be set up, and how the simulation can be parallelized to reduce the simulation time from 17 months to 391 hours using a 32 CPU Linux...

  20. Large-eddy simulation and analytical modelling of katabatic winds

    NARCIS (Netherlands)

    Axelsen, S.L.

    2010-01-01

    This thesis is concerned with numerical and analytical modellig of over sloping terrain, also called katabatic winds. These winds are induced when a stably stratified atmospheric boundary layer is cooled from below. A horizontal potential temperature difference is produced between an air parcel clos

  1. Recent advances in nuclear power plant simulation

    International Nuclear Information System (INIS)

    The field of industrial simulation has experienced very significant progress in recent years, and power plant simulation in particular has been an extremely active area. Improvements may be recorded in practically all simulator subsystems. In Europe, the construction of new full- or optimized-scope nuclear power plant simulators during the middle 1990's has been remarkable intense. In fact, it is possible to identify a distinct simulator generation, which constitutes a new de facto simulation standard. Thomson Training and Simulation has taken part in these developments by designing, building, and validation several of these new simulators for Dutch, German and French nuclear power plants. Their characteristics are discussed in this paper. The following main trends may be identified: Process modeling is clearly evolving towards obtaining engineering-grade performance, even under the added constraints of real-time operation and a very wide range of operating conditions to be covered; Massive use of modern graphic user interfaces (GUI) ensures an unprecedented flexibility and user-friendliness for the Instructor Station; The massive use of GUIs also allows the development of Trainee Stations (TS), which significantly enhance the in-depth training value of the simulators; The development of powerful Software Development Environments (SDE) enables the simulator maintenance teams to keep abreast of modifications carried out in the reference plants; Finally, simulator maintenance and its compliance with simulator fidelity requirements are greatly enhanced by integrated Configuration Management Systems (CMS). In conclusion, the power plant simulation field has attained a strong level of maturity, which benefits its approximately forty years of service to the power generation industry. (author)

  2. Virtual Environments for Advanced Trainers and Simulators

    NARCIS (Netherlands)

    Jense, G.J.; Kuijper, F.

    1993-01-01

    Virtual environment technology is expected to make a big impact on future training and simulation systems. Direct stimulation of human senses (eyesight, auditory, tactile) and new paradigms for user input will improve the realism of simulations and thereby the effectiveness of training systems. Afte

  3. Hybrid and Electric Advanced Vehicle Systems Simulation

    Science.gov (United States)

    Beach, R. F.; Hammond, R. A.; Mcgehee, R. K.

    1985-01-01

    Predefined components connected to represent wide variety of propulsion systems. Hybrid and Electric Advanced Vehicle System (HEAVY) computer program is flexible tool for evaluating performance and cost of electric and hybrid vehicle propulsion systems. Allows designer to quickly, conveniently, and economically predict performance of proposed drive train.

  4. ADVANCE, a modular vehicle simulation environment in MATLAB/SIMULINK

    NARCIS (Netherlands)

    Eelkema, J.; Vink, W.; Tillaart, E. van den

    2002-01-01

    This paper presents the development of a hybrid electric powertrain test platform. In the development process use has been made of ADVANCE, a modular vehicle simulation environment in MATLAB/Simulink. The background, philosophy, and the concept of the ADVANCE tool are discussed and a brief introduct

  5. Modelling of ballistic low energy ion solid interaction - conventional analytic theories versus computer simulations

    International Nuclear Information System (INIS)

    The ''philosophy'' behind, and the ''psychology'' of the development from analytic theory to computer simulations in the field of atomic collisions in solids is discussed and a few examples of achievements and perspectives are given. (orig.)

  6. SIRS Dynamics on Random Networks: Simulations and Analytical Models

    Science.gov (United States)

    Rozhnova, Ganna; Nunes, Ana

    The standard pair approximation equations (PA) for the Susceptible-Infective-Recovered-Susceptible (SIRS) model of infection spread on a network of homogeneous degree k predict a thin phase of sustained oscillations for parameter values that correspond to diseases that confer long lasting immunity. Here we present a study of the dependence of this oscillatory phase on the parameter k and of its relevance to understand the behaviour of simulations on networks. For k = 4, we compare the phase diagram of the PA model with the results of simulations on regular random graphs (RRG) of the same degree. We show that for parameter values in the oscillatory phase, and even for large system sizes, the simulations either die out or exhibit damped oscillations, depending on the initial conditions. This failure of the standard PA model to capture the qualitative behaviour of the simulations on large RRGs is currently being investigated.

  7. Advanced Simulation and Computing Business Plan

    Energy Technology Data Exchange (ETDEWEB)

    Rummel, E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-07-09

    To maintain a credible nuclear weapons program, the National Nuclear Security Administration’s (NNSA’s) Office of Defense Programs (DP) needs to make certain that the capabilities, tools, and expert staff are in place and are able to deliver validated assessments. This requires a complete and robust simulation environment backed by an experimental program to test ASC Program models. This ASC Business Plan document encapsulates a complex set of elements, each of which is essential to the success of the simulation component of the Nuclear Security Enterprise. The ASC Business Plan addresses the hiring, mentoring, and retaining of programmatic technical staff responsible for building the simulation tools of the nuclear security complex. The ASC Business Plan describes how the ASC Program engages with industry partners—partners upon whom the ASC Program relies on for today’s and tomorrow’s high performance architectures. Each piece in this chain is essential to assure policymakers, who must make decisions based on the results of simulations, that they are receiving all the actionable information they need.

  8. Gear Mesh Loss-of-Lubrication Experiments and Analytical Simulation

    Science.gov (United States)

    Handschuh, Robert F.; Polly, Joseph; Morales, Wilfredo

    2011-01-01

    An experimental program to determine the loss-of-lubrication (LOL) characteristics of spur gears in an aerospace simulation test facility has been completed. Tests were conducted using two different emergency lubricant types: (1) an oil mist system (two different misted lubricants) and (2) a grease injection system (two different grease types). Tests were conducted using a NASA Glenn test facility normally used for conducting contact fatigue. Tests were run at rotational speeds up to 10000 rpm using two different gear designs and two different gear materials. For the tests conducted using an air-oil misting system, a minimum lubricant injection rate was determined to permit the gear mesh to operate without failure for at least 1 hr. The tests allowed an elevated steady state temperature to be established. A basic 2-D heat transfer simulation has been developed to investigate temperatures of a simulated gear as a function of frictional behavior. The friction (heat generation source) between the meshing surfaces is related to the position in the meshing cycle, the load applied, and the amount of lubricant in the contact. Experimental conditions will be compared to those from the 2-D simulation.

  9. Microbial Enhanced Oil Recovery - Advanced Reservoir Simulation

    DEFF Research Database (Denmark)

    Nielsen, Sidsel Marie

    to formation of biofilm. The construction of a one-dimensional simulator enables us to investigate how the different mechanisms and the combination of these influence the displacement processes, the saturation profiles and thus the oil recovery curves. The reactive transport model describes...... of the relative permeabilities. Overall, these methods produce similar results. Separate investigations of the surfactant effect have been performed through exemplifying simulation cases, where no biofilm is formed. The water phase saturation profiles are found to contain a waterfront initially...... investigated. A super efficient surfactant produces an incremental recovery recovery around 40 % OOIP over that of waterflooding. Application of the less efficient -- and probably more realistic -- surfactant results in an incremental oil recovery of 9 % OOIP, but it is still considered a significant...

  10. Microbial Enhanced Oil Recovery - Advanced Reservoir Simulation

    OpenAIRE

    Nielsen, Sidsel Marie; Shapiro, Alexander; Stenby, Erling Halfdan; Michelsen, Michael Locht

    2010-01-01

    In this project, a generic model has been set up to include the two main mechanisms in the microbial enhanced oil recovery (MEOR) process; reduction of the interfacial tension (IFT) due to surfactant production, and microscopic fluid diversion as a part of the overall fluid diversion mechanism due to formation of biofilm. The construction of a one-dimensional simulator enables us to investigate how the different mechanisms and the combination of these influence the displacement processes, the...

  11. Advanced numerical techniques in core simulations

    International Nuclear Information System (INIS)

    The whole core simulations are one of the most CPU intensive calculations in reactor physics design and analyses. For a designer it is imperative to perform these calculations with good accuracy and in least time possible to try out various options. It is important for the code developers to use techniques involving minimum approximations and to use most recent numerical methods applied in tandem with huge computing power available today. In the presented paper, some of these methods are discussed. (author)

  12. Advances in NLTE Modeling for Integrated Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Scott, H A; Hansen, S B

    2009-07-08

    The last few years have seen significant progress in constructing the atomic models required for non-local thermodynamic equilibrium (NLTE) simulations. Along with this has come an increased understanding of the requirements for accurately modeling the ionization balance, energy content and radiative properties of different elements for a wide range of densities and temperatures. Much of this progress is the result of a series of workshops dedicated to comparing the results from different codes and computational approaches applied to a series of test problems. The results of these workshops emphasized the importance of atomic model completeness, especially in doubly excited states and autoionization transitions, to calculating ionization balance, and the importance of accurate, detailed atomic data to producing reliable spectra. We describe a simple screened-hydrogenic model that calculates NLTE ionization balance with surprising accuracy, at a low enough computational cost for routine use in radiation-hydrodynamics codes. The model incorporates term splitting, {Delta}n = 0 transitions, and approximate UTA widths for spectral calculations, with results comparable to those of much more detailed codes. Simulations done with this model have been increasingly successful at matching experimental data for laser-driven systems and hohlraums. Accurate and efficient atomic models are just one requirement for integrated NLTE simulations. Coupling the atomic kinetics to hydrodynamics and radiation transport constrains both discretizations and algorithms to retain energy conservation, accuracy and stability. In particular, the strong coupling between radiation and populations can require either very short timesteps or significantly modified radiation transport algorithms to account for NLTE material response. Considerations such as these continue to provide challenges for NLTE simulations.

  13. Process simulation for advanced composites production

    Energy Technology Data Exchange (ETDEWEB)

    Allendorf, M.D.; Ferko, S.M.; Griffiths, S. [Sandia National Labs., Livermore, CA (United States)] [and others

    1997-04-01

    The objective of this project is to improve the efficiency and lower the cost of chemical vapor deposition (CVD) processes used to manufacture advanced ceramics by providing the physical and chemical understanding necessary to optimize and control these processes. Project deliverables include: numerical process models; databases of thermodynamic and kinetic information related to the deposition process; and process sensors and software algorithms that can be used for process control. Target manufacturing techniques include CVD fiber coating technologies (used to deposit interfacial coatings on continuous fiber ceramic preforms), chemical vapor infiltration, thin-film deposition processes used in the glass industry, and coating techniques used to deposit wear-, abrasion-, and corrosion-resistant coatings for use in the pulp and paper, metals processing, and aluminum industries.

  14. On Improving Analytical Models of Cosmic Reionization for Matching Numerical Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Kaurov, Alexander A. [Univ. of Chicago, IL (United States)

    2016-01-01

    The methods for studying the epoch of cosmic reionization vary from full radiative transfer simulations to purely analytical models. While numerical approaches are computationally expensive and are not suitable for generating many mock catalogs, analytical methods are based on assumptions and approximations. We explore the interconnection between both methods. First, we ask how the analytical framework of excursion set formalism can be used for statistical analysis of numerical simulations and visual representation of the morphology of ionization fronts. Second, we explore the methods of training the analytical model on a given numerical simulation. We present a new code which emerged from this study. Its main application is to match the analytical model with a numerical simulation. Then, it allows one to generate mock reionization catalogs with volumes exceeding the original simulation quickly and computationally inexpensively, meanwhile reproducing large scale statistical properties. These mock catalogs are particularly useful for CMB polarization and 21cm experiments, where large volumes are required to simulate the observed signal.

  15. Physical approach to analytic simulation of Fresnel integrals

    Science.gov (United States)

    Anokhov, Sergey

    2007-01-01

    Fresnel integrals continue to find new applications in various areas of human activity, including technology and music. However, performing calculations with them is often hindered by a mathematical peculiarity of these integrals, which is the rapidly oscillating functions of the basic variable. This circumstance complicates the numerical calculations when these integrals need additional integral transformation: convolution, Fourier transform, etc. The suggested solution of the problem consists of replacement of the complex Fresnel integral by a single rational function that simulates this integral in the entire area of its existence with an accuracy up to 10-6. The advantages of the suggested approach are confirmed by the concrete example.

  16. Predicting population dynamics with analytical, simulation and supercomputer models

    Energy Technology Data Exchange (ETDEWEB)

    Onstad, D.W.

    1987-07-01

    A set of epizootiological models describing the influence of a microsporidian disease on the population dynamics of an herbivorous insect demonstrate the similarities and differences between the three major approaches now available for ecological modeling. Simulation modeling allows the incorporation of randomness or the timing of discrete events in the temporal dynamics. More complex models incorporating both temporal and spatial dynamics in variable and heterogeneous environments require the use of supercomputers. Under a number of realistic circumstances, the qualitative predictions of the approaches may differ.

  17. Interoperable Technologies for Advanced Petascale Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiaolin [SUNY at Stony Brook

    2013-01-14

    Our final report on the accomplishments of ITAPS at Stony Brook during period covered by the research award includes component service, interface service and applications. On the component service, we have designed and implemented a robust functionality for the Lagrangian tracking of dynamic interface. We have migrated the hyperbolic, parabolic and elliptic solver from stage-wise second order toward global second order schemes. We have implemented high order coupling between interface propagation and interior PDE solvers. On the interface service, we have constructed the FronTier application programer's interface (API) and its manual page using doxygen. We installed the FronTier functional interface to conform with the ITAPS specifications, especially the iMesh and iMeshP interfaces. On applications, we have implemented deposition and dissolution models with flow and implemented the two-reactant model for a more realistic precipitation at the pore level and its coupling with Darcy level model. We have continued our support to the study of fluid mixing problem for problems in inertial comfinement fusion. We have continued our support to the MHD model and its application to plasma liner implosion in fusion confinement. We have simulated a step in the reprocessing and separation of spent fuels from nuclear power plant fuel rods. We have implemented the fluid-structure interaction for 3D windmill and parachute simulations. We have continued our collaboration with PNNL, BNL, LANL, ORNL, and other SciDAC institutions.

  18. Optimization of a Superconducting Magnetic Energy Storage Device via a CPU-Efficient Semi-Analytical Simulation

    CERN Document Server

    Dimitrov, I K; Solovyov, V F; Chubar, O; Li, Qiang

    2014-01-01

    Recent advances in second generation (YBCO) high temperature superconducting wire could potentially enable the design of super high performance energy storage devices that combine the high energy density of chemical storage with the high power of superconducting magnetic storage. However, the high aspect ratio and considerable filament size of these wires requires the concomitant development of dedicated optimization methods that account for both the critical current density and ac losses in type II superconductors. Here, we report on the novel application and results of a CPU-efficient semi-analytical computer code based on the Radia 3D magnetostatics software package. Our algorithm is used to simulate and optimize the energy density of a superconducting magnetic energy storage device model, based on design constraints, such as overall size and number of coils. The rapid performance of the code is pivoted on analytical calculations of the magnetic field based on an efficient implementation of the Biot-Savart...

  19. Using simple instrumentation to solve complex analytical problems: advanced AAS atomizers for volatile compounds and analyte trapping techniques

    Czech Academy of Sciences Publication Activity Database

    Dědina, Jiří; de Moraes, D. P.; Dessuy, M. B.; Kratzer, Jan; Řezáčová, Olga; Svoboda, Milan; Matoušek, Tomáš; de Moraes Flores, E. M.; Vale, M. G. R.

    2010. s. 59. [Rio Symposium on Atomic Spectrometry /11./. 24.10.2010-29.10.2010, Mar del Plata] R&D Projects: GA ČR GA203/09/1783 Institutional research plan: CEZ:AV0Z40310501 Keywords : AAS * volatile compounds * analyte trapping techniques Subject RIV: CB - Analytical Chemistry, Separation http://www.11thriosymposium.com.ar/index.htm

  20. Experimental and analytical studies of passive shutdown heat removal from advanced LMRs [liquid metal reactors

    International Nuclear Information System (INIS)

    A facility designed and constructed to demonstrate the viability of natural convection passive heat removal systems as a key feature of innovative LMR Shutdown Heat Removal (SHR) systems is in operation at Argonne National Laboratory (ANL). This Natural Convection Shutdown Heat Removal Test Facility (NSTF) has investigated the heat transfer performance of the GE/PRISM passive design. This initial series of experiments simulates the air-side geometry of the PRISM Radiant Reactor Vessel Auxiliary Cooling System (RVACS). The NSTF operates in either a uniform heat flux mode and a uniform temperature mode at the air/guard vessel interface. Analysis of the RVACS performance data indicates excellent agreement with pretest analytical predictions. Correlation analysis presents the heat transfer data in a form suitable for use in LMR design and verification of analytical studies

  1. Numerical simulation and analytical study of glulam timber beams

    Directory of Open Access Journals (Sweden)

    Themistoklis Tsalkatidis

    2014-03-01

    Full Text Available Glulam beams or glued-laminated beams consist of sawn lumber laminations (timber bonded with an adhesive material. This paper, through the mathematical description of the contact conditions that apply at the interfaces of glulam beams and the development of two three-dimensional finite element models by the use of the ANSYS software package, studies the flexural properties of unreinforced (UGB and reinforced (RGB glulam beams. The first computational model presents an unreinforced glulam beam that has been produced by three wood laminations of dimensions 6 by 3.6 by 176 cm. The latter one describes a reinforced glulam beam, which has been produced by gluing a 0.15 cm thick steel plate at the bottom edge of the previously described beam. The computational analysis indicates that the two glulam beams have significantly different bearing capacities under the same load and support conditions. The failure mode of the UGB is brittle whereas the one of the RGB is ductile. The numerical results of both models are in close agreement with experimental ones from the international literature.   Keywords: Glulam Timber Beams, Numerical Simulation, Contact.

  2. Analytical vs. Simulation Solution Techniques for Pulse Problems in Non-linear Stochastic Dynamics

    DEFF Research Database (Denmark)

    Iwankiewicz, R.; Nielsen, Søren R. K.

    Advantages and disadvantages of available analytical and simulation techniques for pulse problems in non-linear stochastic dynamics are discussed. First, random pulse problems, both those which do and do not lead to Markov theory, are presented. Next, the analytical and analytically-numerical tec......Advantages and disadvantages of available analytical and simulation techniques for pulse problems in non-linear stochastic dynamics are discussed. First, random pulse problems, both those which do and do not lead to Markov theory, are presented. Next, the analytical and analytically......-numerical techniques suitable for Markov response problems such as moments equation, Petrov-Galerkin and cell-to-cell mapping techniques are briefly discussed. Usefulness of these techniques is limited by the fact that effectiveness of each of them depends on the mean rate of impulses. Another limitation is the size...... of the problem, i.e. the number of state variables of the dynamical systems. In contrast, the application of the simulation techniques is not limited to Markov problems, nor is it dependent on the mean rate of impulses. Moreover their use is straightforward for a large class of point processes, at...

  3. Analytical simulation of seismic testing of VKL piping system at the HDR test facility

    International Nuclear Information System (INIS)

    The paper describes the analytical modeling, calculations, and results of the posttest simulation of seismic testing of the VKL piping system at the HDR Test Facility in West Germany. A main objective of the tests was to evaluate analytical methods for calculating the seismic response of realistic piping systems subjected to seismic excitation. Six different pipe-support configurations, ranging from a stiff system with struts and snubbers to a very flexible system with practically no seismic supports, were subjected to simulated earthquakes. The posttest calculations cover the stiffest system with snubbers, and a reasonably compliant system with only rigid struts. Responses for 100 to 300% safe-shutdown-earthquake loading were calculated using the piping response module of the SMACS code with multiple, independent support acceleration input. Analytical simulation of the tests was found to somewhat underestimate the responses. The paper discusses the possible explanation for this and the effect on the results of the damping ratios assumed

  4. Analytical positron range modelling in heterogeneous media for PET Monte Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Lehnert, Wencke; Meikle, Steven R [Discipline of Medical Radiation Sciences, Faculty of Health Sciences, University of Sydney, PO Box 170, Lidcombe NSW 1825 (Australia); Gregoire, Marie-Claude; Reilhac, Anthonin, E-mail: wlehnert@uni.sydney.edu.au [Australian Nuclear Science and Technology Organisation, Lucas Heights NSW 2234 (Australia)

    2011-06-07

    Monte Carlo simulation codes that model positron interactions along their tortuous path are expected to be accurate but are usually slow. A simpler and potentially faster approach is to model positron range from analytical annihilation density distributions. The aims of this paper were to efficiently implement and validate such a method, with the addition of medium heterogeneity representing a further challenge. The analytical positron range model was evaluated by comparing annihilation density distributions with those produced by the Monte Carlo simulator GATE and by quantitatively analysing the final reconstructed images of Monte Carlo simulated data. In addition, the influence of positronium formation on positron range and hence on the performance of Monte Carlo simulation was investigated. The results demonstrate that 1D annihilation density distributions for different isotope-media combinations can be fitted with Gaussian functions and hence be described by simple look-up-tables of fitting coefficients. Together with the method developed for simulating positron range in heterogeneous media, this allows for efficient modelling of positron range in Monte Carlo simulation. The level of agreement of the analytical model with GATE depends somewhat on the simulated scanner and the particular research task, but appears to be suitable for lower energy positron emitters, such as {sup 18}F or {sup 11}C. No reliable conclusion about the influence of positronium formation on positron range and simulation accuracy could be drawn.

  5. Just-in-time Time Data Analytics and Visualization of Climate Simulations using the Bellerophon Framework

    Science.gov (United States)

    Anantharaj, V. G.; Venzke, J.; Lingerfelt, E.; Messer, B.

    2015-12-01

    Climate model simulations are used to understand the evolution and variability of earth's climate. Unfortunately, high-resolution multi-decadal climate simulations can take days to weeks to complete. Typically, the simulation results are not analyzed until the model runs have ended. During the course of the simulation, the output may be processed periodically to ensure that the model is preforming as expected. However, most of the data analytics and visualization are not performed until the simulation is finished. The lengthy time period needed for the completion of the simulation constrains the productivity of climate scientists. Our implementation of near real-time data visualization analytics capabilities allows scientists to monitor the progress of their simulations while the model is running. Our analytics software executes concurrently in a co-scheduling mode, monitoring data production. When new data are generated by the simulation, a co-scheduled data analytics job is submitted to render visualization artifacts of the latest results. These visualization output are automatically transferred to Bellerophon's data server located at ORNL's Compute and Data Environment for Science (CADES) where they are processed and archived into Bellerophon's database. During the course of the experiment, climate scientists can then use Bellerophon's graphical user interface to view animated plots and their associated metadata. The quick turnaround from the start of the simulation until the data are analyzed permits research decisions and projections to be made days or sometimes even weeks sooner than otherwise possible! The supercomputer resources used to run the simulation are unaffected by co-scheduling the data visualization jobs, so the model runs continuously while the data are visualized. Our just-in-time data visualization software looks to increase climate scientists' productivity as climate modeling moves into exascale era of computing.

  6. Equipping simulators with an advanced thermal hydraulics model EDF's experience

    International Nuclear Information System (INIS)

    The development of an accelerated version of the advanced CATHARe-1 thermal hydraulics code designed for EDF training simulators (CATHARE-SIMU) was successfully completed as early as 1991. Its successful integration as the principal model of the SIPA Post-Accident Simulator meant that its use could be extended to full-scale simulators as part of the renovation of the stock of existing simulators. In order to further extend the field of application to accidents occurring in shutdown states requiring action and to catch up with developments in respect of the CATHARE code, EDF initiated the SCAR Project designed to adapt CATHARE-2 to simulator requirements (acceleration, parallelization of the computation and extension of the simulation range). In other respects, the installation of SIPA on workstations means that the authors can envisage the application of this remarkable training facility to the understanding of thermal hydraulics accident phenomena

  7. Safety Assessment of Advanced Imaging Sequences II: Simulations

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    2016-01-01

    . The simulation time is between 0.67 ms to 2.8 ms per emission and imaging point, making it possible to simulate even complex emission sequences in less than 1 s for a single spatial position. The linear simulations yield a relative accuracy on MI between -12.1% to 52.3% and for Ispta.3 between -38......An automatic approach for simulating the emitted pressure, intensity, and MI of advanced ultrasound imaging sequences is presented. It is based on a linear simulation of pressure fields using Field II, and it is hypothesized that linear simulation can attain the needed accuracy for predicting...... Mechanical Index (MI) and Ispta.3 as required by FDA. The method is performed on four different imaging schemes and compared to measurements conducted using the SARUS experimental scanner. The sequences include focused emissions with an F-number of 2 with 64 elements that generate highly non-linear fields...

  8. Monte Carlo simulation: tool for the calibration in analytical determination of radionuclides

    International Nuclear Information System (INIS)

    This work shows how is established the traceability of the analytical determinations using this calibration method. Highlights the advantages offered by Monte Carlo simulation for the application of corrections by differences in chemical composition, density and height of the samples analyzed. Likewise, the results obtained by the LVRA in two exercises organized by the International Agency for Atomic Energy (IAEA) are presented. In these exercises (an intercomparison and a proficiency test) all reported analytical results were obtained based on calibrations in efficiency by Monte Carlo simulation using the DETEFF program

  9. Advance in research on aerosol deposition simulation methods

    International Nuclear Information System (INIS)

    A comprehensive analysis of the health effects of inhaled toxic aerosols requires exact data on airway deposition. A knowledge of the effect of inhaled drugs is essential to the optimization of aerosol drug delivery. Sophisticated analytical deposition models can be used for the computation of total, regional and generation specific deposition efficiencies. The continuously enhancing computer seem to allow us to study the particle transport and deposition in more and more realistic airway geometries with the help of computational fluid dynamics (CFD) simulation method. In this article, the trends in aerosol deposition models and lung models, and the methods for achievement of deposition simulations are also reviewed. (authors)

  10. New hybrid voxelized/analytical primitive in Monte Carlo simulations for medical applications

    Science.gov (United States)

    Bert, Julien; Lemaréchal, Yannick; Visvikis, Dimitris

    2016-05-01

    Monte Carlo simulations (MCS) applied in particle physics play a key role in medical imaging and particle therapy. In such simulations, particles are transported through voxelized phantoms derived from predominantly patient CT images. However, such voxelized object representation limits the incorporation of fine elements, such as artificial implants from CAD modeling or anatomical and functional details extracted from other imaging modalities. In this work we propose a new hYbrid Voxelized/ANalytical primitive (YVAN) that combines both voxelized and analytical object descriptions within the same MCS, without the need to simultaneously run two parallel simulations, which is the current gold standard methodology. Given that YVAN is simply a new primitive object, it does not require any modifications on the underlying MC navigation code. The new proposed primitive was assessed through a first simple MCS. Results from the YVAN primitive were compared against an MCS using a pure analytical geometry and the layer mass geometry concept. A perfect agreement was found between these simulations, leading to the conclusion that the new hybrid primitive is able to accurately and efficiently handle phantoms defined by a mixture of voxelized and analytical objects. In addition, two application-based evaluation studies in coronary angiography and intra-operative radiotherapy showed that the use of YVAN was 6.5% and 12.2% faster than the layered mass geometry method, respectively, without any associated loss of accuracy. However, the simplification advantages and differences in computational time improvements obtained with YVAN depend on the relative proportion of the analytical and voxelized structures used in the simulation as well as the size and number of triangles used in the description of the analytical object meshes.

  11. Free-boundary simulations of ITER advanced scenarios

    International Nuclear Information System (INIS)

    The successful operation of ITER advanced scenarios is likely to be a major step forward in the development of controlled fusion as a power production source. ITER advanced scenarios raise specific challenges that are not encountered in presently-operated tokamaks. In this thesis, it is argued that ITER advanced operation may benefit from optimal control techniques. Optimal control ensures high performance operation while guaranteeing tokamak integrity. The application of optimal control techniques for ITER operation is assessed and it is concluded that robust optimisation is appropriate for ITER operation of advanced scenarios. Real-time optimisation schemes are discussed and it is concluded that the necessary conditions of optimality tracking approach may potentially be appropriate for ITER operation, thus offering a viable closed-loop optimal control approach. Simulations of ITER advanced operation are necessary in order to assess the present ITER design and uncover the main difficulties that may be encountered during advanced operation. The DINA-CH and CRONOS full tokamak simulator is used to simulate the operation of the ITER hybrid and steady-state scenarios. It is concluded that the present ITER design is appropriate for performing a hybrid scenario pulse lasting more than 1000 sec, with a flat-top plasma current of 12 MA, and a fusion gain of Q ≅ 8. Similarly, a steady-state scenario without internal transport barrier, with a flat-top plasma current of 10 MA, and with a fusion gain of Q ≅ 5 can be realised using the present ITER design. The sensitivity of the advanced scenarios with respect to transport models and physical assumption is assessed using CRONOS. It is concluded that the hybrid scenario and the steady-state scenario are highly sensitive to the L-H transition timing, to the value of the confinement enhancement factor, to the heating and current drive scenario during ramp-up, and, to a lesser extent, to the density peaking and pedestal

  12. Big data, advanced analytics and the future of comparative effectiveness research.

    Science.gov (United States)

    Berger, Marc L; Doban, Vitalii

    2014-03-01

    The intense competition that accompanied the growth of internet-based companies ushered in the era of 'big data' characterized by major innovations in processing of very large amounts of data and the application of advanced analytics including data mining and machine learning. Healthcare is on the cusp of its own era of big data, catalyzed by the changing regulatory and competitive environments, fueled by growing adoption of electronic health records, as well as efforts to integrate medical claims, electronic health records and other novel data sources. Applying the lessons from big data pioneers will require healthcare and life science organizations to make investments in new hardware and software, as well as in individuals with different skills. For life science companies, this will impact the entire pharmaceutical value chain from early research to postcommercialization support. More generally, this will revolutionize comparative effectiveness research. PMID:24645690

  13. On the multimodality of preparative TREF fractionation as detected by advanced analytical methods.

    Science.gov (United States)

    Ndiripo, Anthony; Pasch, Harald

    2015-08-01

    Preparative temperature rising elution fractionation (prepTREF) is the standard technique for the preparative fractionation of polyolefins according to crystallisability. For olefin copolymers such as linear low-density polyethylene (LLDPE), it was believed that the TREF elution temperature correlates directly with the copolymer composition. For copolymers having different bulk comonomer contents, the prepTREF fractions of different samples collected at a given temperature were assumed to have the same chemical composition. It was acknowledged quite early that co-crystallisation effects may disturb TREF fractionation and fractions are obtained that are not completely homogeneous. This, however, has not been investigated quantitatively so far. The fundamental statement of prepTREF is challenged for the first time quantitatively using advanced analytical techniques including high-temperature high-performance liquid chromatography (HPLC). Ethylene-1-octene copolymers having bulk comonomer contents ranging from 0.3 to 6.4 mol% were fractionated by prepTREF, and the fractions were analysed by high-temperature size exclusion chromatography, crystallisation analysis fractionation, differential scanning calorimetry and high-temperature HPLC. All analytical results prove that the TREF fractions collected from different samples at the same elution temperature have different chemical compositions. The chemical compositions of the fractions correlate with the compositions of the bulk samples in that the comonomer contents of similar TREF fractions increase with an increase of the comonomer content of the bulk samples. These results are in clear contrast to the previous assumption that the TREF fraction composition is independent of the bulk copolymer composition for a given copolymer type. Graphical abstract Advanced analysis of LLDPE by combination of HT-HPLC, DSC and CRYSTAF. PMID:26055883

  14. An analytical model for simulating two-dimensional multispecies plume migration

    Science.gov (United States)

    Chen, Jui-Sheng; Liang, Ching-Ping; Liu, Chen-Wuing; Li, Loretta Y.

    2016-02-01

    The two-dimensional advection-dispersion equations coupled with sequential first-order decay reactions involving arbitrary number of species in groundwater system is considered to predict the two-dimensional plume behavior of decaying contaminant such as radionuclide and dissolved chlorinated solvent. Generalized analytical solutions in compact format are derived through the sequential application of the Laplace, finite Fourier cosine, and generalized integral transform to reduce the coupled partial differential equation system to a set of linear algebraic equations. The system of algebraic equations is next solved for each species in the transformed domain, and the solutions in the original domain are then obtained through consecutive integral transform inversions. Explicit form solutions for a special case are derived using the generalized analytical solutions and are compared with the numerical solutions. The analytical results indicate that the analytical solutions are robust, accurate and useful for simulation or screening tools to assess plume behaviors of decaying contaminants.

  15. Technical Basis for Physical Fidelity of NRC Control Room Training Simulators for Advanced Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Minsk, Brian S.; Branch, Kristi M.; Bates, Edward K.; Mitchell, Mark R.; Gore, Bryan F.; Faris, Drury K.

    2009-10-09

    The objective of this study is to determine how simulator physical fidelity influences the effectiveness of training the regulatory personnel responsible for examination and oversight of operating personnel and inspection of technical systems at nuclear power reactors. It seeks to contribute to the U.S. Nuclear Regulatory Commission’s (NRC’s) understanding of the physical fidelity requirements of training simulators. The goal of the study is to provide an analytic framework, data, and analyses that inform NRC decisions about the physical fidelity requirements of the simulators it will need to train its staff for assignment at advanced reactors. These staff are expected to come from increasingly diverse educational and experiential backgrounds.

  16. Simulating advanced life support systems to test integrated control approaches

    Science.gov (United States)

    Kortenkamp, D.; Bell, S.

    Simulations allow for testing of life support control approaches before hardware is designed and built. Simulations also allow for the safe exploration of alternative control strategies during life support operation. As such, they are an important component of any life support research program and testbed. This paper describes a specific advanced life support simulation being created at NASA Johnson Space Center. It is a discrete-event simulation that is dynamic and stochastic. It simulates all major components of an advanced life support system, including crew (with variable ages, weights and genders), biomass production (with scalable plantings of ten different crops), water recovery, air revitalization, food processing, solid waste recycling and energy production. Each component is modeled as a producer of certain resources and a consumer of certain resources. The control system must monitor (via sensors) and control (via actuators) the flow of resources throughout the system to provide life support functionality. The simulation is written in an object-oriented paradigm that makes it portable, extensible and reconfigurable.

  17. Patient Simulation Software to Augment an Advanced Pharmaceutics Course

    Science.gov (United States)

    Schonder, Kristine

    2011-01-01

    Objective To implement and assess the effectiveness of adding a pharmaceutical care simulation program to an advanced therapeutics course. Design PharmaCAL (University of Pittsburgh), a software program that uses a branched-outcome decision making model, was used to create patient simulations to augment lectures given in the course. In each simulation, students were presented with a challenge, given choices, and then provided with consequences specific to their choices. Assessments A survey was administered at the end of the course and students indicated the simulations were enjoyable (92%), easy to use (90%), stimulated interest in critically ill patients (82%), and allowed for application of lecture material (91%). A 5-item presimulation and postsimulation test on the anemia simulation was administered to assess learning. Students answered significantly more questions correctly on the postsimulation test than on the presimulation test (p < 0.001). Seventy-eight percent of students answered the same 5 questions correctly on the final examination. Conclusion Patient simulation software that used a branched-outcome decision model was an effective supplement to class lectures in an advanced pharmaceutics course and was well-received by pharmacy students. PMID:21519411

  18. Lessons Learned From Dynamic Simulations of Advanced Fuel Cycles

    Energy Technology Data Exchange (ETDEWEB)

    Steven J. Piet; Brent W. Dixon; Jacob J. Jacobson; Gretchen E. Matthern; David E. Shropshire

    2009-04-01

    Years of performing dynamic simulations of advanced nuclear fuel cycle options provide insights into how they could work and how one might transition from the current once-through fuel cycle. This paper summarizes those insights from the context of the 2005 objectives and goals of the Advanced Fuel Cycle Initiative (AFCI). Our intent is not to compare options, assess options versus those objectives and goals, nor recommend changes to those objectives and goals. Rather, we organize what we have learned from dynamic simulations in the context of the AFCI objectives for waste management, proliferation resistance, uranium utilization, and economics. Thus, we do not merely describe “lessons learned” from dynamic simulations but attempt to answer the “so what” question by using this context. The analyses have been performed using the Verifiable Fuel Cycle Simulation of Nuclear Fuel Cycle Dynamics (VISION). We observe that the 2005 objectives and goals do not address many of the inherently dynamic discriminators among advanced fuel cycle options and transitions thereof.

  19. Advanced graphic interface man machine for a simulator of nuclear processes for training in classroom

    International Nuclear Information System (INIS)

    This work describes a working prototype that will serve as experimental platform for the specification and development of a commercial classroom analysis simulator. The classroom analysis simulator will be used as analytical tool for an optimal and more efficient training of operation personnel of Laguna Verde Power Plant. The focus of this work is on the advanced graphical interface of the classroom analysis simulator and those issues involved with its design. This interface offers two distinctive features: 1) virtual representation of instrumentation and controls of different control panels; and 2) direct manipulation as main interaction method. These features provide an easy and intuitive way to manipulate and monitor virtual instrumentation as well as an effortless manner to control the interface. By using object menus with special control features, it is possible to perform visualization functions such as navigation among control panels, location of instrumentation, panning, zooming and reset. The system and its interface provide immediate feedback and reversible operation capabilities allowing an easy, fast and natural human-machine interaction within a graphical environment that the operator is familiar with. The system gives also access and displays a functional copy of the Laguna Verde Safety Parameters Display System. In addition, a special set of graphic displays representing the full animation of transients and severe accidents via output data files from specialized nuclear codes are being designed. The features of the system mentioned above, supported by advanced mathematical models, currently under development, will provide an exceptional simulation environment. It is expected that the simulator will be used not only as an alternative to reduce expensive load of the current hard wire simulator, but also as a powerful extension analytical tool. (Author)

  20. Analytical and experimental simulation of boiling oscillations in sodium with a low-pressure water system

    International Nuclear Information System (INIS)

    An experimental and analytical program designed to simulate sodium boiling under low-power, low-flow conditions has been completed. Experiments were performed using atmospheric- pressure water as a simulant fluid and a simple one-dimensional model was developed for the system. Results indicate that water is a suitable simulant for liquid sodium under certain conditions and that the model does a fair job of modeling the system. In addition, oscillations that occur during the boiling process appear to augment substantially the heat transfer between liquid and vapor in condensation

  1. Simulation and analytic analysis of radiation driven islands at the density limit

    Science.gov (United States)

    Brennan, D. P.; Liu, C.; Gates, D. A.; Delgado-Aparicio, L.; White, R.

    2014-10-01

    The effect of radiative cooling on the onset and evolution of magnetic islands is investigated with nonlinear resistive MHD simulations and reduced theoretical analysis. The configuration is a cylindrical tokamak with a m/n = 2/1 island and includes three dimensional resistivity and anisotropic heat conduction in the simulations. The radiative cooling is implemented as a temperature perturbation inside the island, which modifies the island structure and drives the island more unstable. Analytic reduction of the saturated island size and structure supports the simulation results. The results offer intuitive understanding of experimental observations of radiation driven magnetic islands, which may explain density limit disruptions.

  2. Comparison of analytical model to simulation of diffusion plume from underground CO2 storage

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, K.; Patzek, T.W.; Silin, D.

    2008-12-01

    An exact solution exists for the advection-dispersion equation when the wind profile is modeled with a power-law dependence on height. This analytical solution is compared here to a numerical simulation of the coupled air-ground system for a leaking underground CO{sub 2} storage. The two methods produced similar results far from the boundaries, but the boundary conditions had a strong effect; the simulation imposed boundary conditions at the edge of a finite domain while the analytic solution imposes them at infinity. The reverse seepage from air to ground was shown in the simulation to be very small, and the sharp contrast between time scales suggests that air and ground can be modeled separately, with gas emissions from the ground model used as inputs to the air model.

  3. Integration of Advanced Simulation and Visualization for Manufacturing Process Optimization

    Science.gov (United States)

    Zhou, Chenn; Wang, Jichao; Tang, Guangwu; Moreland, John; Fu, Dong; Wu, Bin

    2016-05-01

    The integration of simulation and visualization can provide a cost-effective tool for process optimization, design, scale-up and troubleshooting. The Center for Innovation through Visualization and Simulation (CIVS) at Purdue University Northwest has developed methodologies for such integration with applications in various manufacturing processes. The methodologies have proven to be useful for virtual design and virtual training to provide solutions addressing issues on energy, environment, productivity, safety, and quality in steel and other industries. In collaboration with its industrial partnerships, CIVS has provided solutions to companies, saving over US38 million. CIVS is currently working with the steel industry to establish an industry-led Steel Manufacturing Simulation and Visualization Consortium through the support of National Institute of Standards and Technology AMTech Planning Grant. The consortium focuses on supporting development and implementation of simulation and visualization technologies to advance steel manufacturing across the value chain.

  4. Advanced Simulation and Computing FY17 Implementation Plan, Version 0

    Energy Technology Data Exchange (ETDEWEB)

    McCoy, Michel [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Archer, Bill [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hendrickson, Bruce [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wade, Doug [National Nuclear Security Administration (NNSA), Washington, DC (United States). Office of Advanced Simulation and Computing and Institutional Research and Development; Hoang, Thuc [National Nuclear Security Administration (NNSA), Washington, DC (United States). Computational Systems and Software Environment

    2016-08-29

    The Stockpile Stewardship Program (SSP) is an integrated technical program for maintaining the safety, surety, and reliability of the U.S. nuclear stockpile. The SSP uses nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of experimental facilities and programs, and the computational capabilities to support these programs. The Advanced Simulation and Computing Program (ASC) is a cornerstone of the SSP, providing simulation capabilities and computational resources that support annual stockpile assessment and certification, study advanced nuclear weapons design and manufacturing processes, analyze accident scenarios and weapons aging, and provide the tools to enable stockpile Life Extension Programs (LEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balance of resource, including technical staff, hardware, simulation software, and computer science solutions. ASC is now focused on increasing predictive capabilities in a three-dimensional (3D) simulation environment while maintaining support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (sufficient resolution, dimensionality, and scientific details), and quantifying critical margins and uncertainties. Resolving each issue requires increasingly difficult analyses because the aging process has progressively moved the stockpile further away from the original test base. Where possible, the program also enables the use of high performance computing (HPC) and simulation tools to address broader national security needs, such as foreign nuclear weapon assessments and counter nuclear terrorism.

  5. Requirements for advanced simulation of nuclear reactor and chemicalseparation plants.

    Energy Technology Data Exchange (ETDEWEB)

    Palmiotti, G.; Cahalan, J.; Pfeiffer, P.; Sofu, T.; Taiwo, T.; Wei,T.; Yacout, A.; Yang, W.; Siegel, A.; Insepov, Z.; Anitescu, M.; Hovland,P.; Pereira, C.; Regalbuto, M.; Copple, J.; Willamson, M.

    2006-12-11

    This report presents requirements for advanced simulation of nuclear reactor and chemical processing plants that are of interest to the Global Nuclear Energy Partnership (GNEP) initiative. Justification for advanced simulation and some examples of grand challenges that will benefit from it are provided. An integrated software tool that has its main components, whenever possible based on first principles, is proposed as possible future approach for dealing with the complex problems linked to the simulation of nuclear reactor and chemical processing plants. The main benefits that are associated with a better integrated simulation have been identified as: a reduction of design margins, a decrease of the number of experiments in support of the design process, a shortening of the developmental design cycle, and a better understanding of the physical phenomena and the related underlying fundamental processes. For each component of the proposed integrated software tool, background information, functional requirements, current tools and approach, and proposed future approaches have been provided. Whenever possible, current uncertainties have been quoted and existing limitations have been presented. Desired target accuracies with associated benefits to the different aspects of the nuclear reactor and chemical processing plants were also given. In many cases the possible gains associated with a better simulation have been identified, quantified, and translated into economical benefits.

  6. Hybrid and electric advanced vehicle systems (heavy) simulation

    Science.gov (United States)

    Hammond, R. A.; Mcgehee, R. K.

    1981-01-01

    A computer program to simulate hybrid and electric advanced vehicle systems (HEAVY) is described. It is intended for use early in the design process: concept evaluation, alternative comparison, preliminary design, control and management strategy development, component sizing, and sensitivity studies. It allows the designer to quickly, conveniently, and economically predict the performance of a proposed drive train. The user defines the system to be simulated using a library of predefined component models that may be connected to represent a wide variety of propulsion systems. The development of three models are discussed as examples.

  7. Advances in Simulation of Wave Interaction with Extended MHD Phenomena

    International Nuclear Information System (INIS)

    The Integrated Plasma Simulator (IPS) provides a framework within which some of the most advanced, massively-parallel fusion modeling codes can be interoperated to provide a detailed picture of the multi-physics processes involved in fusion experiments. The presentation will cover four topics: (1) recent improvements to the IPS, (2) application of the IPS for very high resolution simulations of ITER scenarios, (3) studies of resistive and ideal MHD stability in tokamk discharges using IPS facilities, and (4) the application of RF power in the electron cyclotron range of frequencies to control slowly growing MHD modes in tokamaks and initial evaluations of optimized location for RF power deposition.

  8. Advanced simulation of windmills in electric power supply

    DEFF Research Database (Denmark)

    Akhmatov, Vladislav; Knudsen, Hans; Nielsen, Arne Hejde

    2000-01-01

    An advanced model of a grid-connected windmill is set up where the windmill is a complex electro-mechanical system. The windmill model is implemented as a standardised component in the dynamic simulation tool, PSS/E, which makes it possible to investigate dynamic behaviour of grid-connected windm......An advanced model of a grid-connected windmill is set up where the windmill is a complex electro-mechanical system. The windmill model is implemented as a standardised component in the dynamic simulation tool, PSS/E, which makes it possible to investigate dynamic behaviour of grid......-connected windmills as a part of realistic electrical grid models. That means an arbitrary number of wind farms or single windmills within an arbitrary network configuration. The windmill model may be applied to study of electric power system stability and of power quality as well. It is found that a grid...

  9. Advanced 3D Photocathode Modeling and Simulations Final Report

    International Nuclear Information System (INIS)

    High brightness electron beams required by the proposed Next Linear Collider demand strong advances in photocathode electron gun performance. Significant improvement in the production of such beams with rf photocathode electron guns is hampered by the lack high-fidelity simulations. The critical missing piece in existing gun codes is a physics-based, detailed treatment of the very complex and highly nonlinear photoemission process

  10. International congress on analytical science for advanced material processing and environmental impact assessment

    International Nuclear Information System (INIS)

    The topics covered in the proceedings of the International Congress on Analytical Science 2010 include sampling and sample treatment pre-concentration (including solid phase extraction) organic analytical reagents, chemometrics, quality assurance/quality control, chromatography (GC, HPLC, IC, TLC etc.) and related techniques, hyphenated methods atomic spectroscopy (absorption, emission, fluorescence, XRF, XRD, lasers), molecular spectroscopy (IR, Raman), separation methods in analytical chemistry, sensors. Mass spectrometry, nuclear analytical methods, electroanalytical methods, geoanalytical chemistry, thermal analysis, process analytical chemistry, molecular probes for analyte sensing and imaging, express test methods, surface analytical methods, analytical microscopy, bioanalytical chemistry, environmental analysis, characterization of nano materials, analysis of new materials (including high-purity materials), analysis of food and agricultural products, clinical/forensic analysis, online analysis/process analytical chemistry, novel analytical techniques, lab on chips, LIMS, trace metal analysis and speciation. Papers relevant to INIS are indexed separately

  11. The Consortium for Advanced Simulation of Light Water Reactors

    International Nuclear Information System (INIS)

    The Consortium for Advanced Simulation of Light Water Reactors (CASL) is a DOE Energy Innovation Hub for modeling and simulation of nuclear reactors. It brings together an exceptionally capable team from national labs, industry and academia that will apply existing modeling and simulation capabilities and develop advanced capabilities to create a usable environment for predictive simulation of light water reactors (LWRs). This environment, designated as the Virtual Environment for Reactor Applications (VERA), will incorporate science-based models, state-of-the-art numerical methods, modern computational science and engineering practices, and uncertainty quantification (UQ) and validation against data from operating pressurized water reactors (PWRs). It will couple state-of-the-art fuel performance, neutronics, thermal-hydraulics (T-H), and structural models with existing tools for systems and safety analysis and will be designed for implementation on both today's leadership-class computers and the advanced architecture platforms now under development by the DOE. CASL focuses on a set of challenge problems such as CRUD induced power shift and localized corrosion, grid-to-rod fretting fuel failures, pellet clad interaction, fuel assembly distortion, etc. that encompass the key phenomena limiting the performance of PWRs. It is expected that much of the capability developed will be applicable to other types of reactors. CASL's mission is to develop and apply modeling and simulation capabilities to address three critical areas of performance for nuclear power plants: (1) reduce capital and operating costs per unit energy by enabling power uprates and plant lifetime extension, (2) reduce nuclear waste volume generated by enabling higher fuel burnup, and (3) enhance nuclear safety by enabling high-fidelity predictive capability for component performance.

  12. The Consortium for Advanced Simulation of Light Water Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ronaldo Szilard; Hongbin Zhang; Doug Kothe; Paul Turinsky

    2011-10-01

    The Consortium for Advanced Simulation of Light Water Reactors (CASL) is a DOE Energy Innovation Hub for modeling and simulation of nuclear reactors. It brings together an exceptionally capable team from national labs, industry and academia that will apply existing modeling and simulation capabilities and develop advanced capabilities to create a usable environment for predictive simulation of light water reactors (LWRs). This environment, designated as the Virtual Environment for Reactor Applications (VERA), will incorporate science-based models, state-of-the-art numerical methods, modern computational science and engineering practices, and uncertainty quantification (UQ) and validation against data from operating pressurized water reactors (PWRs). It will couple state-of-the-art fuel performance, neutronics, thermal-hydraulics (T-H), and structural models with existing tools for systems and safety analysis and will be designed for implementation on both today's leadership-class computers and the advanced architecture platforms now under development by the DOE. CASL focuses on a set of challenge problems such as CRUD induced power shift and localized corrosion, grid-to-rod fretting fuel failures, pellet clad interaction, fuel assembly distortion, etc. that encompass the key phenomena limiting the performance of PWRs. It is expected that much of the capability developed will be applicable to other types of reactors. CASL's mission is to develop and apply modeling and simulation capabilities to address three critical areas of performance for nuclear power plants: (1) reduce capital and operating costs per unit energy by enabling power uprates and plant lifetime extension, (2) reduce nuclear waste volume generated by enabling higher fuel burnup, and (3) enhance nuclear safety by enabling high-fidelity predictive capability for component performance.

  13. Improving the trust in results of numerical simulations and scientific data analytics

    Energy Technology Data Exchange (ETDEWEB)

    Cappello, Franck [Argonne National Lab. (ANL), Argonne, IL (United States); Constantinescu, Emil [Argonne National Lab. (ANL), Argonne, IL (United States); Hovland, Paul [Argonne National Lab. (ANL), Argonne, IL (United States); Peterka, Tom [Argonne National Lab. (ANL), Argonne, IL (United States); Phillips, Carolyn [Argonne National Lab. (ANL), Argonne, IL (United States); Snir, Marc [Argonne National Lab. (ANL), Argonne, IL (United States); Wild, Stefan [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-04-30

    This white paper investigates several key aspects of the trust that a user can give to the results of numerical simulations and scientific data analytics. In this document, the notion of trust is related to the integrity of numerical simulations and data analytics applications. This white paper complements the DOE ASCR report on Cybersecurity for Scientific Computing Integrity by (1) exploring the sources of trust loss; (2) reviewing the definitions of trust in several areas; (3) providing numerous cases of result alteration, some of them leading to catastrophic failures; (4) examining the current notion of trust in numerical simulation and scientific data analytics; (5) providing a gap analysis; and (6) suggesting two important research directions and their respective research topics. To simplify the presentation without loss of generality, we consider that trust in results can be lost (or the results’ integrity impaired) because of any form of corruption happening during the execution of the numerical simulation or the data analytics application. In general, the sources of such corruption are threefold: errors, bugs, and attacks. Current applications are already using techniques to deal with different types of corruption. However, not all potential corruptions are covered by these techniques. We firmly believe that the current level of trust that a user has in the results is at least partially founded on ignorance of this issue or the hope that no undetected corruptions will occur during the execution. This white paper explores the notion of trust and suggests recommendations for developing a more scientifically grounded notion of trust in numerical simulation and scientific data analytics. We first formulate the problem and show that it goes beyond previous questions regarding the quality of results such as V&V, uncertainly quantification, and data assimilation. We then explore the complexity of this difficult problem, and we sketch complementary general

  14. Dynamic fault trees resolution: A conscious trade-off between analytical and simulative approaches

    Energy Technology Data Exchange (ETDEWEB)

    Chiacchio, F., E-mail: chiacchio@dmi.unict.it [Dipartimento di Matematica e Informatica-DMI, Universita degli Studi di Catania (Italy); Compagno, L., E-mail: lco@diim.unict.it [Dipartimento di Ingegneria Industriale e Meccanica-DIIM, Universita degli Studi di Catania (Italy); D' Urso, D., E-mail: ddurso@diim.unict.it [Dipartimento di Ingegneria Industriale e Meccanica-DIIM, Universita degli Studi di Catania (Italy); Manno, G., E-mail: gmanno@dmi.unict.it [Dipartimento di Matematica e Informatica-DMI, Universita degli Studi di Catania (Italy); Trapani, N., E-mail: ntrapani@diim.unict.it [Dipartimento di Ingegneria Industriale e Meccanica-DIIM, Universita degli Studi di Catania (Italy)

    2011-11-15

    Safety assessment in industrial plants with 'major hazards' requires a rigorous combination of both qualitative and quantitative techniques of RAMS. Quantitative assessment can be executed by static or dynamic tools of dependability but, while the former are not sufficient to model exhaustively time-dependent activities, the latter are still too complex to be used with success by the operators of the industrial field. In this paper we present a review of the procedures that can be used to solve quite general dynamic fault trees (DFT) that present a combination of the following characteristics: time dependencies, repeated events and generalized probability failure. Theoretical foundations of the DFT theory are discussed and the limits of the most known DFT tools are presented. Introducing the concept of weak and strong hierarchy, the well-known modular approach is adapted to study a more generic class of DFT. In order to quantify the approximations introduced, an ad-hoc simulative environment is used as benchmark. In the end, a DFT of an accidental scenario is analyzed with both analytical and simulative approaches. Final results are in good agreement and prove how it is possible to implement a suitable Monte Carlo simulation with the features of a spreadsheet environment, able to overcome the limits of the analytical tools, thus encouraging further researches along this direction. - Highlights: > Theoretical foundations of the DFT are reviewed and the limits of the analytical techniques are assessed. > Hierarchical technique is discussed, introducing the concepts of weak and strong equivalence. > Simulative environment developed with a spreadsheet electronic document is tested. > Comparison between the simulative and the analytical results is performed. > Classification of which technique is more suitable is provided, depending on the complexity of the DFT.

  15. Dynamic fault trees resolution: A conscious trade-off between analytical and simulative approaches

    International Nuclear Information System (INIS)

    Safety assessment in industrial plants with 'major hazards' requires a rigorous combination of both qualitative and quantitative techniques of RAMS. Quantitative assessment can be executed by static or dynamic tools of dependability but, while the former are not sufficient to model exhaustively time-dependent activities, the latter are still too complex to be used with success by the operators of the industrial field. In this paper we present a review of the procedures that can be used to solve quite general dynamic fault trees (DFT) that present a combination of the following characteristics: time dependencies, repeated events and generalized probability failure. Theoretical foundations of the DFT theory are discussed and the limits of the most known DFT tools are presented. Introducing the concept of weak and strong hierarchy, the well-known modular approach is adapted to study a more generic class of DFT. In order to quantify the approximations introduced, an ad-hoc simulative environment is used as benchmark. In the end, a DFT of an accidental scenario is analyzed with both analytical and simulative approaches. Final results are in good agreement and prove how it is possible to implement a suitable Monte Carlo simulation with the features of a spreadsheet environment, able to overcome the limits of the analytical tools, thus encouraging further researches along this direction. - Highlights: → Theoretical foundations of the DFT are reviewed and the limits of the analytical techniques are assessed. → Hierarchical technique is discussed, introducing the concepts of weak and strong equivalence. → Simulative environment developed with a spreadsheet electronic document is tested. → Comparison between the simulative and the analytical results is performed. → Classification of which technique is more suitable is provided, depending on the complexity of the DFT.

  16. Analytical solutions and particle simulations of cross-field plasma sheaths

    International Nuclear Information System (INIS)

    Particles simulations have been made of an infinite plasma slab, bounded by absorbing conducting walls, with a magnetic field parallel to the walls. The simulations have been either 1-D, or 2-D, with the magnetic field normal to the simulation plane. Initially, the plasma has a uniform density between the walls, and there is a uniform source of ions and electrons to replace particles lost to the walls. In the 1-D case, there is no diffusion of the particle guiding centers, and the plasma remains uniform in density and potential over most of the slab, with sheaths about a Debye length wide where the potential rises to the wall potential. In the 2-D case, the density profile becomes parabolic, going almost to zero at the walls, and there is a quasineutral presheath in the bulk of the plasma, in addition to sheaths near the walls. Analytic expressions are found for the density and potential profiles in both cases, including, in the 2-D case, the magnetic presheath due to finite ion Larmor radius, and the effects of the guiding center diffusion rate being either much less than or much grater than the energy diffusion rate. These analytic expressions are shown to agree with the simulations. A 1-D simulation with Monte Carlo guiding center diffusion included gives results that are good agreement with the much more expensive 2-D simulation. 17 refs., 10 figs

  17. Analytical modeling and simulation of germanium single gate silicon on insulator TFET

    International Nuclear Information System (INIS)

    This paper proposes a new two dimensional (2D) analytical model for a germanium (Ge) single gate silicon-on-insulator tunnel field effect transistor (SG SOI TFET). The parabolic approximation technique is used to solve the 2D Poisson equation with suitable boundary conditions and analytical expressions are derived for the surface potential, the electric field along the channel and the vertical electric field. The device output tunnelling current is derived further by using the electric fields. The results show that Ge based TFETs have significant improvements in on-current characteristics. The effectiveness of the proposed model has been verified by comparing the analytical model results with the technology computer aided design (TCAD) simulation results and also comparing them with results from a silicon based TFET. (semiconductor devices)

  18. Application of system identification to analytic rotor modeling from simulated and wind tunnel dynamic test data, part 2

    Science.gov (United States)

    Hohenemser, K. H.; Banerjee, D.

    1977-01-01

    An introduction to aircraft state and parameter identification methods is presented. A simplified form of the maximum likelihood method is selected to extract analytical aeroelastic rotor models from simulated and dynamic wind tunnel test results for accelerated cyclic pitch stirring excitation. The dynamic inflow characteristics for forward flight conditions from the blade flapping responses without direct inflow measurements were examined. The rotor blades are essentially rigid for inplane bending and for torsion within the frequency range of study, but flexible in out-of-plane bending. Reverse flow effects are considered for high rotor advance ratios. Two inflow models are studied; the first is based on an equivalent blade Lock number, the second is based on a time delayed momentum inflow. In addition to the inflow parameters, basic rotor parameters like the blade natural frequency and the actual blade Lock number are identified together with measurement bias values. The effect of the theoretical dynamic inflow on the rotor eigenvalues is evaluated.

  19. An Advanced Analytical Chemistry Experiment Using Gas Chromatography-Mass Spectrometry, MATLAB, and Chemometrics to Predict Biodiesel Blend Percent Composition

    Science.gov (United States)

    Pierce, Karisa M.; Schale, Stephen P.; Le, Trang M.; Larson, Joel C.

    2011-01-01

    We present a laboratory experiment for an advanced analytical chemistry course where we first focus on the chemometric technique partial least-squares (PLS) analysis applied to one-dimensional (1D) total-ion-current gas chromatography-mass spectrometry (GC-TIC) separations of biodiesel blends. Then, we focus on n-way PLS (n-PLS) applied to…

  20. Leveraging advanced data analytics, machine learning, and metrology models to enable critical dimension metrology solutions for advanced integrated circuit nodes

    Science.gov (United States)

    Rana, Narender; Zhang, Yunlin; Kagalwala, Taher; Bailey, Todd

    2014-10-01

    Integrated circuit (IC) technology is changing in multiple ways: 193i to extreme ultraviolet exposure, planar to nonplanar device architecture, from single exposure lithography to multiple exposure and directed self-assembly (DSA) patterning, and so on. Critical dimension (CD) control requirement is becoming stringent and more exhaustive: CD and process windows are shrinking, three-sigma CD control of patterning. The accuracy of CD-AFM is ˜1 nm and the precision in TEM is poor due to limited statistics. CD scanning electron microscopy (CD-SEM), scatterometry, and MBIR need to be calibrated by reference measurements for ensuring the accuracy of patterned CDs and patterning models. There is a dire need for a measurement with patterning simulation and metrology models and data integration techniques to selected applications demonstrating the potential solution and practicality of such an approach to enhance CD metrology accuracy. Data from multiple metrology techniques have been analyzed in multiple ways to extract information with associated uncertainties and integrated to extract the useful and more accurate CD and profile information of the structures. This paper presents the optimization of scatterometry and MBIR model calibration and the feasibility to extrapolate not only in design and process space but also from one process step to a previous process step. A well-calibrated scatterometry model or patterning simulation model can be used to accurately extrapolate and interpolate in the design and process space for lithography patterning where AFM is not capable of accurately measuring sub-40 nm trenches. The uncertainty associated with extrapolation can be large and needs to be minimized. We have made use of measurements from CD-SEM and CD-AFM, along with the patterning and scatterometry simulation models to estimate the uncertainty associated with extrapolation and the methods to reduce it. For the first time, we have reported the application of machine

  1. Advanced studies on Simulation Methodologies for very Complicated Fracture Phenomena

    International Nuclear Information System (INIS)

    Although nowadays, computational techniques are well developed, for Extremely Complicated Fracture Phenomena, they are still very difficult to simulate, for general engineers, researchers. To overcome many difficulties in those simulations, we have developed not only Simulation Methodologies but also theoretical basis and concepts. We sometimes observe extremely complicated fracture patterns, especially in dynamic fracture phenomena such as dynamic crack branching, kinking, curving, etc. For examples, although the humankind, from primitive men to modern scientists such as Albert Einstein had watched the post-mortem patterns of dynamic crack branching, the governing condition for the onset of the phenomena had been unsolved until our experimental study. From in these studies, we found the governing condition of dynamic crack bifurcation, as follows. When the total energy flux per unit time into a propagating crack tip reaches the material crack resistance, the crack braches into two cracks [total energy flux criterion]. The crack branches many times whenever the criterion is satisfied. Furthermore, the complexities also arise due to their time-dependence and/or their-deformation dependence. In order to make it possible to simulate such extremely complicated fracture phenomena, we developed many original advanced computational methods and technologies. These are (i) moving finite element method based on Delaunay automatic triangulation (MFEMBOAT), path independent, (ii) equivalent domain integral expression of the dynamic J integral associated with a continuous auxiliary function, (iii) Mixed phase path-prediction mode simulation, (iv) implicit path prediction criterion. In this paper, these advanced computational methods are thoroughly explained together with successful comparison with the experimental results. Since multiple dynamic crack branching phenomena may be most complicated fracture due to complicated fracture paths, and its time dependence (transient

  2. A CRITICAL STUDY AND COMPARISON OF MANUFACTURING SIMULATION SOFTWARES USING ANALYTIC HIERARCHY PROCESS

    Directory of Open Access Journals (Sweden)

    ASHU GUPTA

    2010-03-01

    Full Text Available In a period of continuous change in global business environment, organizations, large and small, are finding it increasingly difficult to deal with, and adjust to the demands for such change. Simulation is a powerful tool for allowing designers imagines new systems and enabling them to both quantify and observe behavior. Currently the market offers a variety of simulation software packages. Some are less expensive than others. Some are generic and can be used in a wide variety of application areas while others are more specific. Some have powerful features for modeling while others provide only basic features. Modeling approaches and strategies are different for different packages. Companies are seeking advice about the desirable features of software for manufacturing simulation, depending on the purpose of its use. Because of this, the importance of an adequate approach to simulation software evaluation and comparison is apparent. This paper presents a critical evaluation of four widely used manufacturing simulators: NX-IDEAS, Star-CD, Micro Saint Sharp and ProModel. Following a review of research into simulation software evaluation, an evaluation and comparison of the above simulators is performed. This paper illustrates and assesses the role the Analytic Hierarchy Process (AHP played in simulation software evaluation and selection. The main purpose of this evaluation and comparison is to discover the suitability of certain types of simulators for particular purposes.

  3. Analytical model for non-thermal pressure in galaxy clusters II: Comparison with cosmological hydrodynamics simulation

    CERN Document Server

    Shi, Xun; Nelson, Kaylea; Nagai, Daisuke

    2014-01-01

    Turbulent gas motion inside galaxy clusters provides a non-negligible non-thermal pressure support to the intracluster gas. If not corrected, it leads to a systematic bias in the estimation of cluster masses from X-ray and Sunyaev-Zel'dovich (SZ) observations assuming hydrostatic equilibrium, and affects interpretation of measurements of the SZ power spectrum and observations of cluster outskirts from ongoing and upcoming large cluster surveys. Recently, Shi & Komatsu (2014) developed an analytical model for predicting the radius, mass, and redshift dependence of the non-thermal pressure contributed by the kinetic random motions of intracluster gas sourced by the cluster mass growth. In this paper, we compare the predictions of this analytical model to a state-of-the-art cosmological hydrodynamics simulation. As different mass growth histories result in different non-thermal pressure, we perform the comparison on 65 simulated galaxy clusters on a cluster-by-cluster basis. We find an excellent agreement be...

  4. Analytical modelling and study of the stability characteristics of the Advanced Heavy Water Reactor

    International Nuclear Information System (INIS)

    An analytical model has been developed to study the thermohydraulic and neutronic-coupled density-wave instability in the Indian Advanced Heavy Water Reactor (AHWR) which is a natural circulation pressure tube type boiling water reactor. The model considers a point kinetics model for the neutron dynamics and a lumped parameter model for the fuel thermal dynamics along with the conservation equations of mass, momentum and energy and equation of state for the coolant. In addition, to study the effect of neutron interactions between different parts of the core, the model considers a coupled multipoint kinetics equation in place of simple point kinetics equation. Linear stability theory was applied to reveal the instability of in-phase and out-of-phase modes in the boiling channels of the AHWR. The results indicate that the design configuration considered may experience both Ledinegg and Type I and Type II density-wave instabilities depending on the operating condition. Some methods of suppressing these instabilities were found out. In addition, it was found that the stability behavior of the reactor is greatly influenced by the void reactivity coefficient, fuel time constant, radial power distribution and channel inlet orificing. The delayed neutrons were found to have strong influence on the Type I and Type II instabilities. Decay ratio maps were predicted considering various operating parameters of the reactor, which are useful for its design. (author)

  5. Recent advances in analytical determination of cisplatin and its hydrolysis products

    International Nuclear Information System (INIS)

    Cisplatin (cis-diaminedichloroplatinum [II] is a coordination compound, used in the treatment of several solid tumors. Cisplatin and its hydrolysis products exhibit a great pharmacological effect but are very toxic and probably carcinogenic. The present review summarizes the most important advances in the last years in the techniques employed for the detection and quantification of cisplatin and its hydrolysis products and in the different matrixes studied. The new emerging techniques and their modifications recently developed, fundamentally the combined use of detection and separation techniques for the analysis of platinum species and their impact on the speed, sensitivity and specificity of the analytical determination, with regard to the techniques used in the last century are discussed. High-Performance Liquid Chromatography and Capillary Electrophoresis, coupled with detection methods such as Mass Spectrometry, Inductively Coupled Plasma-Mass Spectrometry, Atomic Absorption Spectrometry and more recently, High-Field Asymmetric Waveform Ion Mobility Spectrometry are the methods more employed. The analysis of cisplatin and its hydrolysis products in new and more complex matrixes is also presented

  6. Analytical modeling and numerical simulations of the thermal behavior of bipolar transistors

    OpenAIRE

    Marano, Ilaria

    2008-01-01

    The thermal behavior of various bipolar transistor categories, namely, trench-isolated (1) SOI BJTs, (2) BJTs fabricated on silicon substrates, and (3) SiGe HBTs, is thorougly analyzed. Detailed 3-D numerical simulations are employed to provide a deep understanding of the thermal process in all the structures. Based on the numerical analysis, novel highly-effective analytical thermal models are conceived and developed for a fully predictive detection of the temperature field corresponding to ...

  7. NUMERICAL SIMULATION OF STRESS-INDUCED SECONDARY FLOWS WITH HYBRID FINITE ANALYTIC METHOD

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The algorithm of the Hybrid Finite Analytic Method (HFAM) was used to simulate fully developed trubulent flows in non-circular ducts and open channels. And the turbulent flow fields in a square duct and a rectangular open channels were calculated by Naot and Rodi's model, and that in a compound channel was calculated by Speaizle's non-linear eddy-viscosity model with this algorithm. The results show that the HFAM is suitable for calculating these complicated turbulent flows.

  8. An Analytical Gate-All-Around MOSFET Model for Circuit Simulation

    Directory of Open Access Journals (Sweden)

    Kuan-Chou Lin

    2015-01-01

    Full Text Available A generic charge-based compact model for undoped (lightly doped quadruple-gate (QG and cylindrical-gate MOSFETs using Verilog-A is developed. This model is based on the exact solution of Poisson’s equation with scale length. The fundamental DC and charging currents of QG MOSFETs are physically and analytically calculated. In addition, as the Verilog-A modeling is portable for different circuit simulators, the modeling scheme provides a useful tool for circuit designers.

  9. A comparison of numerical simulations and analytical theory of the dynamics of interacting magnetic vortices

    International Nuclear Information System (INIS)

    Magnetostatic interactions between vortices in closely spaced planar structures are important for applications including vortex-based magnonic crystals and spin torque oscillator networks. Analytical theories that include magnetostatic interaction effects have been proposed but have not yet been rigorously tested. Here, we compare micromagnetic simulations of the dynamics of magnetic vortices confined in three disks in an equilateral triangle configuration to analytical theories that include coupling. Micromagnetic simulations show that the magnetostatic coupling between the disks leads to splitting of the gyrotropic resonance into three modes and that the frequency splitting increases with decreasing separation. The temporal profiles of the magnetization depend on the vortex polarities and chiralities; however, the frequencies depend only on the polarity combinations and will fall into one of two categories: all polarities equal or one polarity opposite to the others, where the latter leads to a larger frequency splitting. Although the magnitude of the splitting observed in the simulations is larger than what is expected based on purely dipolar interactions, a simple analytical model that assumes dipole-dipole coupling captures the functional form of the frequency splitting and the motion patterns just as well as more complex models

  10. Combined analytical FEM approach for efficient simulation of Lamb wave damage detection.

    Science.gov (United States)

    Shen, Yanfeng; Giurgiutiu, Victor

    2016-07-01

    Lamb waves have been widely explored as a promising inspection tool for non-destructive evaluation (NDE) and structural health monitoring (SHM). This article presents a combined analytical finite element model (FEM) approach (CAFA) for the accurate, efficient, and versatile simulation of 2-D Lamb wave propagation and interaction with damage. CAFA used a global analytical solution to model wave generation, propagation, scattering, mode conversion, and detection, while the wave-damage interaction coefficients (WDICs) were extracted from harmonic analysis of local FEM with non-reflective boundaries (NRB). The analytical procedure was coded using MATLAB, and a predictive simulation tool called WaveFormRevealer 2-D was developed. The methodology of obtaining WDICs from local FEM was presented. Case studies were carried out for Lamb wave propagation in a pristine plate and a damaged plate. CAFA predictions compared well with full scale multi-physics FEM simulations and experiments with scanning laser Doppler vibrometry (SLDV), while achieving remarkable performance in computational efficiency and computer resource saving compared with conventional FEM. PMID:27085109

  11. Simulation of fission products behavior in severe accidents for advanced passive PWR

    International Nuclear Information System (INIS)

    Highlights: • A fission product analysis model based on thermal hydraulic module is developed. • An assessment method for fission product release and transport is constructed. • Fission products behavior during three modes of containment response is investigated. • Source term results for the three modes of containment response are obtained. - Abstract: Fission product behavior for common Pressurized Water Reactor (PWR) has been studied for many years, and some analytical tools have developed. However, studies specifically on the behavior of fission products related to advanced passive PWR is scarce. In the current study, design characteristics of advanced passive PWR influencing fission product behavior are investigated. An integrated fission products analysis model based on a thermal hydraulic module is developed, and the assessment method for fission products release and transport for advanced passive PWR is constructed. Three modes of containment response are simulated, including intact containment, containment bypass and containment overpressure failure. Fission products release from the core and corium, fission products transport and deposition in the Reactor Coolant System (RCS), fission products transport and deposition in the containment considering fission products retention in the in-containment refueling water storage tank (IRWST) and in the secondary side of steam generators (SGs) are simulated. Source term results of intact containment, containment bypass and containment overpressure failure are obtained, which can be utilized to evaluate the radiological consequences

  12. Advance simulation capability for environmental management (ASCEM) - 59065

    International Nuclear Information System (INIS)

    The United States Department Energy (DOE) Office of Environmental Management (EM) determined that uniform application of advanced modeling in the subsurface could help reduce the cost and risks associated with its environmental cleanup mission. In response to this determination, the EM Office of Technology Innovation and Development (OTID), Groundwater and Soil Remediation (GW and S) began the program Advanced Simulation Capability for Environmental Management (ASCEM). ASCEM is a state-of-the-art scientific tool and approach for integrating data and scientific understanding to enable prediction of contaminant fate and transport in natural and engineered systems. This initiative supports the reduction of uncertainties and risks associated with EM?s environmental cleanup and closure programs through better understanding and quantifying the subsurface flow and contaminant transport behavior in complex geological systems. This involves the long-term performance of engineered components, including cementitious materials in nuclear waste disposal facilities that may be sources for future contamination of the subsurface. This paper describes the ASCEM tools and approach and the ASCEM programmatic accomplishments completed in 2010 including recent advances and technology transfer. The US Department of Energy Office of Environmental Management has begun development of an Advanced Simulation Capability for Environmental Management, (ASCEM). This program will provide predictions of the end states of contaminated areas allowing for cost and risk reduction of EM remedial activities. ASCEM will provide the tools and approaches necessary to standardize risk and performance assessments across the DOE complex. Through its Phase One demonstration, the ASCEM team has shown value to the EM community in the areas of High Performance Computing, Data Management, Visualization, and Uncertainty Quantification. In 2012, ASCEM will provide an initial limited release of a community code for

  13. Simulated herbivory advances autumn phenology in Acer rubrum

    Science.gov (United States)

    Forkner, Rebecca E.

    2014-05-01

    To determine the degree to which herbivory contributes to phenotypic variation in autumn phenology for deciduous trees, red maple ( Acer rubrum) branches were subjected to low and high levels of simulated herbivory and surveyed at the end of the season to assess abscission and degree of autumn coloration. Overall, branches with simulated herbivory abscised ˜7 % more leaves at each autumn survey date than did control branches within trees. While branches subjected to high levels of damage showed advanced phenology, abscission rates did not differ from those of undamaged branches within trees because heavy damage induced earlier leaf loss on adjacent branch nodes in this treatment. Damaged branches had greater proportions of leaf area colored than undamaged branches within trees, having twice the amount of leaf area colored at the onset of autumn and having ˜16 % greater leaf area colored in late October when nearly all leaves were colored. When senescence was scored as the percent of all leaves abscised and/or colored, branches in both treatments reached peak senescence earlier than did control branches within trees: dates of 50 % senescence occurred 2.5 days earlier for low herbivory branches and 9.7 days earlier for branches with high levels of simulated damage. These advanced rates are of the same time length as reported delays in autumn senescence and advances in spring onset due to climate warming. Thus, results suggest that should insect damage increase as a consequence of climate change, it may offset a lengthening of leaf life spans in some tree species.

  14. Advances in numerical simulation of nonlinear water waves

    CERN Document Server

    Ma, Qingwei

    2014-01-01

    Most of the Earth's surface is covered by water. Our everyday lives and activities are affected by water waves in oceans, such as the tsunami that occurred in the Indian Ocean on 26 December 2004. This indicates how important it is for us to fully understand water waves, in particular the very large ones. One way to do so is to perform numerical simulation based on the nonlinear theory. Considerable research advances have been made in this area over the past decade by developing various numerical methods and applying them to emerging problems; however, until now there has been no comprehensive

  15. Advances in the analytical methodologies: Profiling steroids in familiar pathways-challenging dogmas.

    Science.gov (United States)

    Bloem, Liezl M; Storbeck, Karl-Heinz; Swart, Pieter; du Toit, Therina; Schloms, Lindie; Swart, Amanda C

    2015-09-01

    . Undoubtedly, the continuous advances in the analytical methodologies used for steroid profiling and quantification will give impetus to the unraveling of the remaining enigmas, old and new, of both hormone biosynthesis and metabolism. PMID:25869556

  16. New Developments in the Simulation of Advanced Accelerator Concepts

    International Nuclear Information System (INIS)

    Improved computational methods are essential to the diverse and rapidly developing field of advanced accelerator concepts. We present an overview of some computational algorithms for laser-plasma concepts and high-brightness photocathode electron sources. In particular, we discuss algorithms for reduced laser-plasma models that can be orders of magnitude faster than their higher-fidelity counterparts, as well as important on-going efforts to include relevant additional physics that has been previously neglected. As an example of the former, we present 2D laser wakefield accelerator simulations in an optimal Lorentz frame, demonstrating and gt;10 GeV energy gain of externally injected electrons over a 2 m interaction length, showing good agreement with predictions from scaled simulations and theory, with a speedup factor of ∼2,000 as compared to standard particle-in-cell.

  17. Advanced Simulations of Optical Transition and Diffraction Radiation

    CERN Document Server

    AUTHOR|(CDS)2078350; Bobb, Lorraine Marie; Bolzon, B; Bravin, Enrico; Karataev, Pavel; Kruchinin, Konstantin; Lefevre, Thibaut; Mazzoni, Stefano

    2015-01-01

    Charged particle beam diagnostics is a key task in modern and future accelerator installations. The diagnostic tools are practically the “eyes” of the operators. The precision and resolution of the diagnostic equipment are crucial to define the performance of the accelerator. Transition and diffraction radiation (TR and DR) are widely used for electron beam parameter monitoring. However, the precision and resolution of those devices are determined by how well the production, transport and detection of these radiation types are understood. This paper reports on simulations of TR and DR spatial-spectral characteristics using the physical optics propagation (POP) mode of the Zemax advanced optics simulation software. A good consistency with theory is demonstrated. Also, realistic optical system alignment issues are discussed.

  18. Efficient parallelization of analytic bond-order potentials for large-scale atomistic simulations

    Science.gov (United States)

    Teijeiro, C.; Hammerschmidt, T.; Drautz, R.; Sutmann, G.

    2016-07-01

    Analytic bond-order potentials (BOPs) provide a way to compute atomistic properties with controllable accuracy. For large-scale computations of heterogeneous compounds at the atomistic level, both the computational efficiency and memory demand of BOP implementations have to be optimized. Since the evaluation of BOPs is a local operation within a finite environment, the parallelization concepts known from short-range interacting particle simulations can be applied to improve the performance of these simulations. In this work, several efficient parallelization methods for BOPs that use three-dimensional domain decomposition schemes are described. The schemes are implemented into the bond-order potential code BOPfox, and their performance is measured in a series of benchmarks. Systems of up to several millions of atoms are simulated on a high performance computing system, and parallel scaling is demonstrated for up to thousands of processors.

  19. Advanced electrical simulation of thin film solar cells

    International Nuclear Information System (INIS)

    Advanced electrical simulation of copper indium gallium diselenide solar cells is illustrated by setting up a demonstration case in SCAPS (Solar Cell Capacitance Simulator), the solar cell simulation programme of the University of Gent. The model includes band gap grading, multivalent defects and metastable transitions between defects. This simplified demonstration model clearly and quantitatively illustrates some topics that were extensively discussed in recent literature: metastable defects exist in either an acceptor or in a donor configuration; the occupation of these configurations is set during initial conditions at higher temperature, and then frozen in during cell operation at lower temperature. These occupations can strongly influence the effective doping profile in the absorber, and hence possible energy barriers in the structure. The dependence of such barriers on the initial conditions and on the operating voltage can cause a considerable dependence of the current–voltage characteristics on the initial conditions, especially of the fill factor. At the same time, the demonstration model illustrates some of the recent extensions of SCAPS. - Highlights: ► SCAPS, the Solar Cell Capacitance Simulator of UGent is freely available. ► SCAPS is keeping up with the sophistication of state-of-the-art solar cells. ► It can now handle: multivalent and metastable defects; grading of all properties. ► It is shown how metastable defects can lead to metastable cell characteristics. ► A relation conduction band barrier-fill factor is numerically established

  20. Leveraging Smart Meter Data through Advanced Analytics: Applications to Building Energy Efficiency

    Science.gov (United States)

    Jalori, Saurabh

    The poor energy efficiency of buildings is a major barrier to alleviating the energy dilemma. Historically, monthly utility billing data was widely available and analytical methods for identifying building energy efficiency improvements, performing building Monitoring and Verification (M&V) and continuous commissioning (CCx) were based on them. Although robust, these methods were not sensitive enough to detect a number of common causes for increased energy use. In recent years, prevalence of short-term building energy consumption data, also known as Energy Interval Data (EID), made available through the Smart Meters, along with data mining techniques presents the potential of knowledge discovery inherent in this data. This allows more sophisticated analytical tools to be developed resulting in greater sensitivities due to higher prediction accuracies; leading to deep energy savings and highly efficient building system operations. The research explores enhancements to Inverse Statistical Modeling techniques due to the availability of EID. Inverse statistical modeling is the process of identification of prediction model structure and estimates of model parameters. The methodology is based on several common statistical and data mining techniques: cluster analysis for day typing, outlier detection and removal, and generation of building scheduling. Inverse methods are simpler to develop and require fewer inputs for model identification. They can model changes in energy consumption based on changes in climatic variables and up to a certain extent, occupancy. This makes them easy-to-use and appealing to building managers for evaluating any general retrofits, building condition monitoring, continuous commissioning and short-term load forecasting (STLF). After evaluating several model structures, an elegant model form was derived which can be used to model daily energy consumption; which can be extended to model energy consumption for any specific hour by adding corrective

  1. Conjugate heat transfer simulations of advanced research reactor fuel

    International Nuclear Information System (INIS)

    Highlights: • Temperature predictions are enhanced by coupling heat transfer in solid and fluid zones. • Seven different cases are considered to observe trends in predicted temperature and pressure. • The seven cases consider high/medium/low power, flow, burnup, fuel material and geometry. • Simulations provide temperature predictions for performance/safety. Boiling is unlikely. • Simulations demonstrate that a candidate geometry can enhance performance/safety. - Abstract: The current work presents numerical simulations of coupled fluid flow and heat transfer of advanced U–Mo/Al and U–Mo/Mg research reactor fuels in support of performance and safety analyses. The objective of this study is to enhance predictions of the flow regime and fuel temperatures through high fidelity simulations that better capture various heat transfer pathways and with a more realistic geometric representation of the fuel assembly in comparison to previous efforts. Specifically, thermal conduction, convection and radiation mechanisms are conjugated between the solid and fluid regions. Also, a complete fuel element assembly is represented in three dimensional space, permitting fluid flow and heat transfer to be simulated across the entire domain. Seven case studies are examined that vary the coolant inlet conditions, specific power, and burnup to investigate the predicted changes in the pressure drop in the coolant and the fuel, clad and coolant temperatures. In addition, an alternate fuel geometry is considered with helical fins (replacing straight fins in the existing design) to investigate the relative changes in predicted fluid and solid temperatures. Numerical simulations predict that the clad temperature is sensitive to changes in the thermal boundary layer in the coolant, particularly in simultaneously developing flow regions, while the temperature in the fuel is anticipated to be unaffected. Finally, heat transfer between fluid and solid regions is enhanced with

  2. A Virtual Engineering Framework for Simulating Advanced Power System

    Energy Technology Data Exchange (ETDEWEB)

    Mike Bockelie; Dave Swensen; Martin Denison; Stanislav Borodai

    2008-06-18

    In this report is described the work effort performed to provide NETL with VE-Suite based Virtual Engineering software and enhanced equipment models to support NETL's Advanced Process Engineering Co-simulation (APECS) framework for advanced power generation systems. Enhancements to the software framework facilitated an important link between APECS and the virtual engineering capabilities provided by VE-Suite (e.g., equipment and process visualization, information assimilation). Model enhancements focused on improving predictions for the performance of entrained flow coal gasifiers and important auxiliary equipment (e.g., Air Separation Units) used in coal gasification systems. In addition, a Reduced Order Model generation tool and software to provide a coupling between APECS/AspenPlus and the GE GateCycle simulation system were developed. CAPE-Open model interfaces were employed where needed. The improved simulation capability is demonstrated on selected test problems. As part of the project an Advisory Panel was formed to provide guidance on the issues on which to focus the work effort. The Advisory Panel included experts from industry and academics in gasification, CO2 capture issues, process simulation and representatives from technology developers and the electric utility industry. To optimize the benefit to NETL, REI coordinated its efforts with NETL and NETL funded projects at Iowa State University, Carnegie Mellon University and ANSYS/Fluent, Inc. The improved simulation capabilities incorporated into APECS will enable researchers and engineers to better understand the interactions of different equipment components, identify weaknesses and processes needing improvement and thereby allow more efficient, less expensive plants to be developed and brought on-line faster and in a more cost-effective manner. These enhancements to APECS represent an important step toward having a fully integrated environment for performing plant simulation and engineering

  3. An analytical model for radioactive pollutant release simulation in the atmospheric boundary layer

    Energy Technology Data Exchange (ETDEWEB)

    Weymar, Guilherme J.; Vilhena, Marco T.; Bodmann, Bardo E.J., E-mail: guicefetrs@gmail.com, E-mail: mtmbvilhena@gmail.com, E-mail: bejbodmann@gmail.com [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica; Buske, Daniela; Quadros, Regis, E-mail: danielabuske@gmail.com, E-mail: quadros99@gmail.com [Universidade Federal de Pelotas (UFPel), Capao do Leao, RS (Brazil). Programa de Pos-Graduacao em Modelagem Matematica

    2013-07-01

    Simulations of emission of radioactive substances in the atmosphere from the Brazilian nuclear power plant Angra 1 are a necessary tool for control and elaboration of emergency plans as a preventive action for possible accidents. In the present work we present an analytical solution for radioactive pollutant dispersion in the atmosphere, solving the time-dependent three-dimensional advection-diffusion equation. The experiment here used as a reference in the simulations consisted of the controlled releases of radioactive tritiated water vapor from the meteorological tower close to the power plant at Itaorna Beach. The wind profile was determined using experimental meteorological data and the micrometeorological parameters were calculated from empirical equations obtained in the literature. We report on a novel analytical formulation for the concentration of products of a radioactive chain released in the atmospheric boundary layer and solve the set of coupled equations for each chain radionuclide by the GILTT solution, assuming the decay of all progenitors radionuclide for each equation as source term. Further we report on numerical simulations, as an explicit but fictitious example and consider three radionuclides in the radioactive chain of Uranium 235. (author)

  4. Tools for advanced simulations to nuclear propulsion systems in rockets

    Energy Technology Data Exchange (ETDEWEB)

    Torres Sepulveda, A.; Perez Vara, R.

    2004-07-01

    While chemical propulsion rockets have dominated space exploration, other forms of rocket propulsion based on nuclear power, electrostatic and magnetic drive, and other principles besides chemical reactions, have been considered from the earliest days of the field. The goal of most of these advanced rocket propulsion schemes is improved efficiency through higher exhaust velocities, in order to reduce the amount of fuel the rocket vehicle needs to carry, though generally at the expense of high thrust. Nuclear propulsion seems to be the most promising short term technology to plan realistic interplanetary missions. The development of a nuclear electric propulsion spacecraft shall require the development of models to analyse the mission and to understand the interaction between the related subsystems (nuclear reactor, electrical converter, power management and distribution, and electric propulsion) during the different phases of the mission. This paper explores the modelling of a nuclear electric propulsion (NEP) spacecraft type using EcosimPro simulation software. This software is a multi-disciplinary simulation tool with a powerful object-oriented simulation language and state-of-the-art solvers. EcosimPro is the recommended ESA simulation tool for environmental Control and Life Support Systems (ECLSS) and has been used successfully within the framework of the European activities of the International Space Station programme. Furthermore, propulsion libraries for chemical and electrical propulsion are currently being developed under ESA contracts to set this tool as standard usage in the propulsion community. At present, there is not any workable NEP spacecraft, but a standardized-modular, multi-purpose interplanetary spacecraft for post-2000 missions, called ISC-2000, has been proposed in reference. The simulation model presented on this paper is based on the preliminary designs for this spacecraft. (Author)

  5. Integration of CATHENA thermal-hydraulic model with CANDU 6 analytical simulator controller

    International Nuclear Information System (INIS)

    This paper introduces a powerful design and analysis tool named SIMCAT that is developed to support applications to license a CANDU nuclear reactor, refurbish projects, and support the existing CANDU stations. It consists of the Canadian Algorithm for THErmohydraulic Network Analysis (CATHENA), the control logics from CANDU6 Analytical Simulator (C6SIM), and a communication protocol, Parallel Virtual Machine (PVM). This is the first time that CATHENA has been successfully coupled directly with a program written in another language. The independence of CATHENA and the C6SIM controllers allows the development of both CATHENA and C6SIM controller to proceed independently. (author)

  6. Investigations and advanced concepts on gyrotron interaction modeling and simulations

    Energy Technology Data Exchange (ETDEWEB)

    Avramidis, K. A., E-mail: konstantinos.avramidis@kit.edu [Institute for Pulsed Power and Microwave Technologies, Karlsruhe Institute of Technology, Karlsruhe 76131 (Germany)

    2015-12-15

    In gyrotron theory, the interaction between the electron beam and the high frequency electromagnetic field is commonly modeled using the slow variables approach. The slow variables are quantities that vary slowly in time in comparison to the electron cyclotron frequency. They represent the electron momentum and the high frequency field of the resonant TE modes in the gyrotron cavity. For their definition, some reference frequencies need to be introduced. These include the so-called averaging frequency, used to define the slow variable corresponding to the electron momentum, and the carrier frequencies, used to define the slow variables corresponding to the field envelopes of the modes. From the mathematical point of view, the choice of the reference frequencies is, to some extent, arbitrary. However, from the numerical point of view, there are arguments that point toward specific choices, in the sense that these choices are advantageous in terms of simulation speed and accuracy. In this paper, the typical monochromatic gyrotron operation is considered, and the numerical integration of the interaction equations is performed by the trajectory approach, since it is the fastest, and therefore it is the one that is most commonly used. The influence of the choice of the reference frequencies on the interaction simulations is studied using theoretical arguments, as well as numerical simulations. From these investigations, appropriate choices for the values of the reference frequencies are identified. In addition, novel, advanced concepts for the definitions of these frequencies are addressed, and their benefits are demonstrated numerically.

  7. Integrated homeland security system with passive thermal imaging and advanced video analytics

    Science.gov (United States)

    Francisco, Glen; Tillman, Jennifer; Hanna, Keith; Heubusch, Jeff; Ayers, Robert

    2007-04-01

    for creating initial alerts - we refer to this as software level detection, the next level building block Immersive 3D visual assessment for situational awareness and to manage the reaction process - we refer to this as automated intelligent situational awareness, a third building block Wide area command and control capabilities to allow control from a remote location - we refer to this as the management and process control building block integrating together the lower level building elements. In addition, this paper describes three live installations of complete, total systems that incorporate visible and thermal cameras as well as advanced video analytics. Discussion of both system elements and design is extensive.

  8. Advanced modeling and simulation to design and manufacture high performance and reliable advanced microelectronics and microsystems.

    Energy Technology Data Exchange (ETDEWEB)

    Nettleship, Ian (University of Pittsburgh, Pittsburgh, PA); Hinklin, Thomas; Holcomb, David Joseph; Tandon, Rajan; Arguello, Jose Guadalupe, Jr. (,; .); Dempsey, James Franklin; Ewsuk, Kevin Gregory; Neilsen, Michael K.; Lanagan, Michael (Pennsylvania State University, University Park, PA)

    2007-07-01

    An interdisciplinary team of scientists and engineers having broad expertise in materials processing and properties, materials characterization, and computational mechanics was assembled to develop science-based modeling/simulation technology to design and reproducibly manufacture high performance and reliable, complex microelectronics and microsystems. The team's efforts focused on defining and developing a science-based infrastructure to enable predictive compaction, sintering, stress, and thermomechanical modeling in ''real systems'', including: (1) developing techniques to and determining materials properties and constitutive behavior required for modeling; (2) developing new, improved/updated models and modeling capabilities, (3) ensuring that models are representative of the physical phenomena being simulated; and (4) assessing existing modeling capabilities to identify advances necessary to facilitate the practical application of Sandia's predictive modeling technology.

  9. Analytical solutions of minimum ionization particle induced current shapes of silicon detectors and simulation of charge collection properties

    International Nuclear Information System (INIS)

    A new analytical, one dimensional method to obtain the induced current shapes and simulation of chasrge shapes for p+ -n-n+ silicon detectors in the case of minimum ionization particle has been developed here. jExact solutions have been found for both electron and hole current shapes. Simulations of induced charge shapes of detectors have also been given. The results of this work are consistent with the earlier work where a semi-analytical method had been used

  10. Semi-analytical treatment of fracture/matrix flow in a dual-porosity simulator for unsaturated fractured rock masses

    International Nuclear Information System (INIS)

    A semi-analytical dual-porosity simulator for unsaturated flow in fractured rock masses has been developed. Fluid flow between the fracture network and the matrix blocks is described by analytical expressions that have been derived from approximate solutions to the imbibition equation. These expressions have been programmed into the unsaturated flow simulator, TOUGH, as a source/sink term. Flow processes are then simulated using only fracture elements in the computational grid. The modified code is used to simulate flow along single fractures, and infiltration into pervasively fractured formations

  11. Simulation of an Electromagnetic Acoustic Transducer Array by Using Analytical Method and FDTD

    Directory of Open Access Journals (Sweden)

    Yuedong Xie

    2016-01-01

    Full Text Available Previously, we developed a method based on FEM and FDTD for the study of an Electromagnetic Acoustic Transducer Array (EMAT. This paper presents a new analytical solution to the eddy current problem for the meander coil used in an EMAT, which is adapted from the classic Deeds and Dodd solution originally intended for circular coils. The analytical solution resulting from this novel adaptation exploits the large radius extrapolation and shows several advantages over the finite element method (FEM, especially in the higher frequency regime. The calculated Lorentz force density from the analytical EM solver is then coupled to the ultrasonic simulations, which exploit the finite-difference time-domain (FDTD method to describe the propagation of ultrasound waves, in particular for Rayleigh waves. Radiation pattern obtained with Hilbert transform on time-domain waveforms is proposed to characterise the sensor in terms of its beam directivity and field distribution along the steering angle, which can produce performance parameters for an EMAT array, facilitating the optimum design of such sensors.

  12. Lumped parameter analytic modeling and behavioral simulation of a 3-DOF MEMS gyro-accelerometer

    Science.gov (United States)

    Verma, Payal; Arya, Sandeep K.; Gopal, Ram

    2015-12-01

    A new analytical model of a 3-degree-of-freedom (3-DOF) gyro-accelerometer system consisting of a 1-DOF drive and 2-DOF sense modes is presented. The model constructs lumped differential equations associated with each DOF of the system by vector analysis. The coupled differential equations thus established are solved analytically for their responses in both the time and frequency domains. Considering these frequency response equations, novel device design concepts are derived by forcing the sense phase to zero, which leads to a certain relationship between the structural frequencies, thereby causing minimization of the damping effect on the performance of the system. Furthermore, the feasibility of the present gyro-accelerometer structure is studied using a unique discriminatory scheme for the detection of both gyro action and linear acceleration at their events. This scheme combines the formulated settled transient solution of the gyro-accelerometer with the processes of synchronous demodulation and filtration, which leads to the in-phase and quadrature components of the system's output signal. These two components can be utilized in the detection of angular motion and linear acceleration. The obtained analytical results are validated by simulation in a MATLAB/Simulink environment, and it is found that the results are in excellent agreement with each other.

  13. Wave-like warp propagation in circumbinary discs I. Analytic theory and numerical simulations

    CERN Document Server

    Facchini, Stefano; Price, Daniel J

    2013-01-01

    In this paper we analyse the propagation of warps in protostellar circumbinary discs. We use these systems as a test environment in which to study warp propagation in the bending-wave regime, with the addition of an external torque due to the binary gravitational potential. In particular, we want to test the linear regime, for which an analytic theory has been developed. In order to do so, we first compute analytically the steady state shape of an inviscid disc subject to the binary torques. The steady state tilt is a monotonically increasing function of radius. In the absence of viscosity, the disc does not present any twist. Then, we compare the time-dependent evolution of the warped disc calculated via the known linearised equations both with the analytic solutions and with full 3D numerical simulations, which have been performed with the PHANTOM SPH code using 2 million particles. We find a good agreement both in the tilt and in the phase evolution for small inclinations, even at very low viscosities. Mor...

  14. Predicting playing frequencies for clarinets: A comparison between numerical simulations and simplified analytical formulas.

    Science.gov (United States)

    Coyle, Whitney L; Guillemain, Philippe; Kergomard, Jean; Dalmont, Jean-Pierre

    2015-11-01

    When designing a wind instrument such as a clarinet, it can be useful to be able to predict the playing frequencies. This paper presents an analytical method to deduce these playing frequencies using the input impedance curve. Specifically there are two control parameters that have a significant influence on the playing frequency, the blowing pressure and reed opening. Four effects are known to alter the playing frequency and are examined separately: the flow rate due to the reed motion, the reed dynamics, the inharmonicity of the resonator, and the temperature gradient within the clarinet. The resulting playing frequencies for the first register of a particular professional level clarinet are found using the analytical formulas presented in this paper. The analytical predictions are then compared to numerically simulated results to validate the prediction accuracy. The main conclusion is that in general the playing frequency decreases above the oscillation threshold because of inharmonicity, then increases above the beating reed regime threshold because of the decrease of the flow rate effect. PMID:26627753

  15. Study on advancement of in vivo counting using mathematical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Kinase, Sakae [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-05-01

    To obtain an assessment of the committed effective dose, individual monitoring for the estimation of intakes of radionuclides is required. For individual monitoring of exposure to intakes of radionuclides, direct measurement of radionuclides in the body - in vivo counting- is very useful. To advance in a precision in vivo counting which fulfills the requirements of ICRP 1990 recommendations, some problems, such as the investigation of uncertainties in estimates of body burdens by in vivo counting, and the selection of the way to improve the precision, have been studied. In the present study, a calibration technique for in vivo counting application using Monte Carlo simulation was developed. The advantage of the technique is that counting efficiency can be obtained for various shapes and sizes that are very difficult to change for phantoms. To validate the calibration technique, the response functions and counting efficiencies of a whole-body counter installed in JAERI were evaluated using the simulation and measurements. Consequently, the calculations are in good agreement with the measurements. The method for the determination of counting efficiency curves as a function of energy was developed using the present technique and a physiques correction equation was derived from the relationship between parameters of correction factor and counting efficiencies of the JAERI whole-body counter. The uncertainties in body burdens of {sup 137}Cs estimated with the JAERI whole-body counter were also investigated using the Monte Carlo simulation and measurements. It was found that the uncertainties of body burdens estimated with the whole-body counter are strongly dependent on various sources of uncertainty such as radioactivity distribution within the body and counting statistics. Furthermore, the evaluation method of the peak efficiencies of a Ge semi-conductor detector was developed by Monte Carlo simulation for optimum arrangement of Ge semi-conductor detectors for

  16. Study on advancement of in vivo counting using mathematical simulation

    International Nuclear Information System (INIS)

    To obtain an assessment of the committed effective dose, individual monitoring for the estimation of intakes of radionuclides is required. For individual monitoring of exposure to intakes of radionuclides, direct measurement of radionuclides in the body - in vivo counting- is very useful. To advance in a precision in vivo counting which fulfills the requirements of ICRP 1990 recommendations, some problems, such as the investigation of uncertainties in estimates of body burdens by in vivo counting, and the selection of the way to improve the precision, have been studied. In the present study, a calibration technique for in vivo counting application using Monte Carlo simulation was developed. The advantage of the technique is that counting efficiency can be obtained for various shapes and sizes that are very difficult to change for phantoms. To validate the calibration technique, the response functions and counting efficiencies of a whole-body counter installed in JAERI were evaluated using the simulation and measurements. Consequently, the calculations are in good agreement with the measurements. The method for the determination of counting efficiency curves as a function of energy was developed using the present technique and a physiques correction equation was derived from the relationship between parameters of correction factor and counting efficiencies of the JAERI whole-body counter. The uncertainties in body burdens of 137Cs estimated with the JAERI whole-body counter were also investigated using the Monte Carlo simulation and measurements. It was found that the uncertainties of body burdens estimated with the whole-body counter are strongly dependent on various sources of uncertainty such as radioactivity distribution within the body and counting statistics. Furthermore, the evaluation method of the peak efficiencies of a Ge semi-conductor detector was developed by Monte Carlo simulation for optimum arrangement of Ge semi-conductor detectors for designing a

  17. Plastic deformation of crystals: analytical and computer simulation studies of dislocation glide

    Energy Technology Data Exchange (ETDEWEB)

    Altintas, S.

    1978-05-01

    The plastic deformation of crystals is usually accomplished through the motion of dislocations. The glide of a dislocation is impelled by the applied stress and opposed by microstructural defects such as point defects, voids, precipitates and other dislocations. The planar glide of a dislocation through randomly distributed obstacles is considered. The objective of the present research work is to calculate the critical resolved shear stress (CRSS) for athermal glide and the velocity of the dislocation at finite temperature as a function of the applied stress and the nature and strength of the obstacles. Dislocation glide through mixtures of obstacles has been studied analytically and by computer simulation. Arrays containing two kinds of obstacles as well as square distribution of obstacle strengths are considered. The critical resolved shear stress for an array containing obstacles with a given distribution of strengths is calculated using the sum of the quadratic mean of the stresses for the individual obstacles and is found to be in good agreement with the computer simulation data. Computer simulation of dislocation glide through randomly distributed obstacles containing up to 10/sup 6/ obstacles show that the CRSS decreases as the size of the array increases and approaches a limiting value. Histograms of forces and of segment lengths are obtained and compared with theoretical predictions. Effects of array shape and boundary conditions on the dislocation glide are also studied. Analytical and computer simulation results are compared with experimental results obtained on precipitation-, irradiation-, forest-, and impurity cluster-hardening systems and are found to be in good agreement.

  18. TID Simulation of Advanced CMOS Devices for Space Applications

    Science.gov (United States)

    Sajid, Muhammad

    2016-07-01

    This paper focuses on Total Ionizing Dose (TID) effects caused by accumulation of charges at silicon dioxide, substrate/silicon dioxide interface, Shallow Trench Isolation (STI) for scaled CMOS bulk devices as well as at Buried Oxide (BOX) layer in devices based on Silicon-On-Insulator (SOI) technology to be operated in space radiation environment. The radiation induced leakage current and corresponding density/concentration electrons in leakage current path was presented/depicted for 180nm, 130nm and 65nm NMOS, PMOS transistors based on CMOS bulk as well as SOI process technologies on-board LEO and GEO satellites. On the basis of simulation results, the TID robustness analysis for advanced deep sub-micron technologies was accomplished up to 500 Krad. The correlation between the impact of technology scaling and magnitude of leakage current with corresponding total dose was established utilizing Visual TCAD Genius program.

  19. A study of reset mode in advanced alarm system simulator

    International Nuclear Information System (INIS)

    An automation function has been widely applied in main control room of nuclear power plants. That leads to a new issue of human-automation interaction, which considers human operational performance in automated systems. In this research is the automation alarm reset in the advanced alarm system (AAS) of Advanced Nuclear Power Plant in Taiwan. Since alarms are very crucial for the understanding of the status of the plant as well as the reset function of alarm system will be changed from fully manual to fully automatic, it is very important to test and evaluate the performance and the effect of reset modes in AAS. The purpose of this paper is to evaluate the impact of the auto-reset alarm system on the plant performance and on operators' preference and task load. To develop a dynamic simulator as an AAS was conducted to compare manual and automatic reset function of alarm system on task performance and subjective ratings of task workload, comprehension, and preference. The simulation includes PCTRAN model and alarm software processing. The final results revealed that, using the auto-reset mode, participants had lower task load index (TLX) on effort in the first test trial and was more satisfied in multiple tasks condition. In contrast, using manual reset mode, participants were more satisfied on alarm handling, monitoring, and decision making. In other words, either reset mode in the study has unique features to assist operator, but is insufficient. The reset function in AAS therefore should be very flexible. Additionally, the experimental results also pointed out that the user interfaces need to be improved. Those experiences will be helpful for human factors verification and validation in the near future. (authors)

  20. Simulated Interactive Research Experiments as Educational Tools for Advanced Science

    Science.gov (United States)

    Tomandl, Mathias; Mieling, Thomas; Losert-Valiente Kroon, Christiane M.; Hopf, Martin; Arndt, Markus

    2015-09-01

    Experimental research has become complex and thus a challenge to science education. Only very few students can typically be trained on advanced scientific equipment. It is therefore important to find new tools that allow all students to acquire laboratory skills individually and independent of where they are located. In a design-based research process we have investigated the feasibility of using a virtual laboratory as a photo-realistic and scientifically valid representation of advanced scientific infrastructure to teach modern experimental science, here, molecular quantum optics. We found a concept based on three educational principles that allows undergraduate students to become acquainted with procedures and concepts of a modern research field. We find a significant increase in student understanding using our Simulated Interactive Research Experiment (SiReX), by evaluating the learning outcomes with semi-structured interviews in a pre/post design. This suggests that this concept of an educational tool can be generalized to disseminate findings in other fields.

  1. Evaluation of FTIR-based analytical methods for the analysis of simulated wastes

    International Nuclear Information System (INIS)

    Three FTIR-based analytical methods that have potential to characterize simulated waste tank materials have been evaluated. These include: (1) fiber optics, (2) modular transfer optic using light guides equipped with non-contact sampling peripherals, and (3) photoacoustic spectroscopy. Pertinent instrumentation and experimental procedures for each method are described. The results show that the near-infrared (NIR) region of the infrared spectrum is the region of choice for the measurement of moisture in waste simulants. Differentiation of the NIR spectrum, as a preprocessing steps, will improve the analytical result. Preliminary data indicate that prominent combination bands of water and the first overtone band of the ferrocyanide stretching vibration may be utilized to measure water and ferrocyanide species simultaneously. Both near-infrared and mid-infrared spectra must be collected, however, to measure ferrocyanide species unambiguously and accurately. For ease of sample handling and the potential for field or waste tank deployment, the FTIR-Fiber Optic method is preferred over the other two methods. Modular transfer optic using light guides and photoacoustic spectroscopy may be used as backup systems and for the validation of the fiber optic data

  2. Charge transport in a-Si:H detectors: Comparison of analytical and Monte Carlo simulations

    International Nuclear Information System (INIS)

    To understand the signal formation in hydrogenated amorphous silicon (a-Si:H) p-i-n detectors, dispersive charge transport due to multiple trapping in a-Si:H tail states is studied both analytically and by Monte Carlo simulations. An analytical solution is found for the free electron and hole distributions n(x,t) and the transient current I(t) due to an initial electron-hole pair generated at an arbitrary depth in the detector for the case of exponential band tails and linear field profiles; integrating over all e-h pairs produced along the particle's trajectory yields the actual distributions and current; the induced charge Q(t) is obtained by numerically integrating the current. This generalizes previous models used to analyze time-of-flight experiments. The Monte Carlo simulation provides the same information but can be applied to arbitrary field profiles, field dependent mobilities and localized state distributions. A comparison of both calculations is made in a simple case to show that identical results are obtained over a large time domain. A comparison with measured signals confirms that the total induced charge depends on the applied bias voltage. The applicability of the same approach to other semiconductors is discussed

  3. Global Simulation of Bioenergy Crop Productivity: Analytical framework and Case Study for Switchgrass

    Energy Technology Data Exchange (ETDEWEB)

    Nair, S. Surendran [University of Tennessee, Knoxville (UTK); Nichols, Jeff A. {Cyber Sciences} [ORNL; Post, Wilfred M [ORNL; Wang, Dali [ORNL; Wullschleger, Stan D [ORNL; Kline, Keith L [ORNL; Wei, Yaxing [ORNL; Singh, Nagendra [ORNL; Kang, Shujiang [ORNL

    2014-01-01

    Contemporary global assessments of the deployment potential and sustainability aspects of biofuel crops lack quantitative details. This paper describes an analytical framework capable of meeting the challenges associated with global scale agro-ecosystem modeling. We designed a modeling platform for bioenergy crops, consisting of five major components: (i) standardized global natural resources and management data sets, (ii) global simulation unit and management scenarios, (iii) model calibration and validation, (iv) high-performance computing (HPC) modeling, and (v) simulation output processing and analysis. A case study with the HPC- Environmental Policy Integrated Climate model (HPC-EPIC) to simulate a perennial bioenergy crop, switchgrass (Panicum virgatum L.) and global biomass feedstock analysis on grassland demonstrates the application of this platform. The results illustrate biomass feedstock variability of switchgrass and provide insights on how the modeling platform can be expanded to better assess sustainable production criteria and other biomass crops. Feedstock potentials on global grasslands and within different countries are also shown. Future efforts involve developing databases of productivity, implementing global simulations for other bioenergy crops (e.g. miscanthus, energycane and agave), and assessing environmental impacts under various management regimes. We anticipated this platform will provide an exemplary tool and assessment data for international communities to conduct global analysis of biofuel biomass feedstocks and sustainability.

  4. Global Simulation of Bioenergy Crop Productivity: Analytical Framework and Case Study for Switchgrass

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Shujiang [ORNL; Kline, Keith L [ORNL; Nair, S. Surendran [University of Tennessee, Knoxville (UTK); Nichols, Dr Jeff A [ORNL; Post, Wilfred M [ORNL; Brandt, Craig C [ORNL; Wullschleger, Stan D [ORNL; Wei, Yaxing [ORNL; Singh, Nagendra [ORNL

    2013-01-01

    A global energy crop productivity model that provides geospatially explicit quantitative details on biomass potential and factors affecting sustainability would be useful, but does not exist now. This study describes a modeling platform capable of meeting many challenges associated with global-scale agro-ecosystem modeling. We designed an analytical framework for bioenergy crops consisting of six major components: (i) standardized natural resources datasets, (ii) global field-trial data and crop management practices, (iii) simulation units and management scenarios, (iv) model calibration and validation, (v) high-performance computing (HPC) simulation, and (vi) simulation output processing and analysis. The HPC-Environmental Policy Integrated Climate (HPC-EPIC) model simulated a perennial bioenergy crop, switchgrass (Panicum virgatum L.), estimating feedstock production potentials and effects across the globe. This modeling platform can assess soil C sequestration, net greenhouse gas (GHG) emissions, nonpoint source pollution (e.g., nutrient and pesticide loss), and energy exchange with the atmosphere. It can be expanded to include additional bioenergy crops (e.g., miscanthus, energy cane, and agave) and food crops under different management scenarios. The platform and switchgrass field-trial dataset are available to support global analysis of biomass feedstock production potential and corresponding metrics of sustainability.

  5. Wave-like warp propagation in circumbinary discs - I. Analytic theory and numerical simulations

    Science.gov (United States)

    Facchini, Stefano; Lodato, Giuseppe; Price, Daniel J.

    2013-08-01

    In this paper we analyse the propagation of warps in protostellar circumbinary discs. We use these systems as a test environment in which to study warp propagation in the bending-wave regime, with the addition of an external torque due to the binary gravitational potential. In particular, we want to test the linear regime, for which an analytic theory has been developed. In order to do so, we first compute analytically the steady-state shape of an inviscid disc subject to the binary torques. The steady-state tilt is a monotonically increasing function of radius, but misalignment is found at the disc inner edge. In the absence of viscosity, the disc does not present any twist. Then, we compare the time-dependent evolution of the warped disc calculated via the known linearized equations both with the analytic solutions and with full 3D numerical simulations. The simulations have been performed with the PHANTOM smoothed particle hydrodynamics (SPH) code using two million particles. We find a good agreement both in the tilt and in the phase evolution for small inclinations, even at very low viscosities. Moreover, we have verified that the linearized equations are able to reproduce the diffusive behaviour when α > H/R, where α is the disc viscosity parameter. Finally, we have used the 3D simulations to explore the non-linear regime. We observe a strongly non-linear behaviour, which leads to the breaking of the disc. Then, the inner disc starts precessing with its own precessional frequency. This behaviour has already been observed with numerical simulations in accretion discs around spinning black holes. The evolution of circumstellar accretion discs strongly depends on the warp evolution. Therefore, the issue explored in this paper could be of fundamental importance in order to understand the evolution of accretion discs in crowded environments, when the gravitational interaction with other stars is highly likely, and in multiple systems. Moreover, the evolution of

  6. Advancements in Afterbody Radiative Heating Simulations for Earth Entry

    Science.gov (United States)

    Johnston, Christopher O.; Panesi, Marco; Brandis, Aaron M.

    2016-01-01

    Four advancements to the simulation of backshell radiative heating for Earth entry are presented. The first of these is the development of a flow field model that treats electronic levels of the dominant backshell radiator, N, as individual species. This is shown to allow improvements in the modeling of electron-ion recombination and two-temperature modeling, which are shown to increase backshell radiative heating by 10 to 40%. By computing the electronic state populations of N within the flow field solver, instead of through the quasi-steady state approximation in the radiation code, the coupling of radiative transition rates to the species continuity equations for the levels of N, including the impact of non-local absorption, becomes feasible. Implementation of this additional level of coupling between the flow field and radiation codes represents the second advancement presented in this work, which is shown to increase the backshell radiation by another 10 to 50%. The impact of radiative transition rates due to non-local absorption indicates the importance of accurate radiation transport in the relatively complex flow geometry of the backshell. This motivates the third advancement, which is the development of a ray-tracing radiation transport approach to compute the radiative transition rates and divergence of the radiative flux at every point for coupling to the flow field, therefore allowing the accuracy of the commonly applied tangent-slab approximation to be assessed for radiative source terms. For the sphere considered at lunar-return conditions, the tangent-slab approximation is shown to provide a sufficient level of accuracy for the radiative source terms, even for backshell cases. This is in contrast to the agreement between the two approaches for computing the radiative flux to the surface, which differ by up to 40%. The final advancement presented is the development of a nonequilibrium model for NO radiation, which provides significant backshell

  7. The advanced computational testing and simulation toolkit (ACTS)

    Energy Technology Data Exchange (ETDEWEB)

    Drummond, L.A.; Marques, O.

    2002-05-21

    During the past decades there has been a continuous growth in the number of physical and societal problems that have been successfully studied and solved by means of computational modeling and simulation. Distinctively, a number of these are important scientific problems ranging in scale from the atomic to the cosmic. For example, ionization is a phenomenon as ubiquitous in modern society as the glow of fluorescent lights and the etching on silicon computer chips; but it was not until 1999 that researchers finally achieved a complete numerical solution to the simplest example of ionization, the collision of a hydrogen atom with an electron. On the opposite scale, cosmologists have long wondered whether the expansion of the Universe, which began with the Big Bang, would ever reverse itself, ending the Universe in a Big Crunch. In 2000, analysis of new measurements of the cosmic microwave background radiation showed that the geometry of the Universe is flat, and thus the Universe will continue expanding forever. Both of these discoveries depended on high performance computer simulations that utilized computational tools included in the Advanced Computational Testing and Simulation (ACTS) Toolkit. The ACTS Toolkit is an umbrella project that brought together a number of general purpose computational tool development projects funded and supported by the U.S. Department of Energy (DOE). These tools, which have been developed independently, mainly at DOE laboratories, make it easier for scientific code developers to write high performance applications for parallel computers. They tackle a number of computational issues that are common to a large number of scientific applications, mainly implementation of numerical algorithms, and support for code development, execution and optimization. The ACTS Toolkit Project enables the use of these tools by a much wider community of computational scientists, and promotes code portability, reusability, reduction of duplicate efforts

  8. Enabling Advanced Modeling and Simulations for Fuel-Flexible Combustors

    Energy Technology Data Exchange (ETDEWEB)

    Heinz Pitsch

    2010-05-31

    The overall goal of the present project is to enable advanced modeling and simulations for the design and optimization of fuel-flexible turbine combustors. For this purpose we use a high-fidelity, extensively-tested large-eddy simulation (LES) code and state-of-the-art models for premixed/partially-premixed turbulent combustion developed in the PI's group. In the frame of the present project, these techniques are applied, assessed, and improved for hydrogen enriched premixed and partially premixed gas-turbine combustion. Our innovative approaches include a completely consistent description of flame propagation, a coupled progress variable/level set method to resolve the detailed flame structure, and incorporation of thermal-diffusion (non-unity Lewis number) effects. In addition, we have developed a general flamelet-type transformation holding in the limits of both non-premixed and premixed burning. As a result, a model for partially premixed combustion has been derived. The coupled progress variable/level method and the general flamelet tranformation were validated by LES of a lean-premixed low-swirl burner that has been studied experimentally at Lawrence Berkeley National Laboratory. The model is extended to include the non-unity Lewis number effects, which play a critical role in fuel-flexible combustor with high hydrogen content fuel. More specifically, a two-scalar model for lean hydrogen and hydrogen-enriched combustion is developed and validated against experimental and direct numerical simulation (DNS) data. Results are presented to emphasize the importance of non-unity Lewis number effects in the lean-premixed low-swirl burner of interest in this project. The proposed model gives improved results, which shows that the inclusion of the non-unity Lewis number effects is essential for accurate prediction of the lean-premixed low-swirl flame.

  9. Enabling Advanced Modeling and Simulations for Fuel-Flexible Combustors

    Energy Technology Data Exchange (ETDEWEB)

    Pitsch, Heinz

    2010-05-31

    The overall goal of the present project is to enable advanced modeling and simulations for the design and optimization of fuel-flexible turbine combustors. For this purpose we use a high fidelity, extensively-tested large-eddy simulation (LES) code and state-of-the-art models for premixed/partially-premixed turbulent combustion developed in the PI's group. In the frame of the present project, these techniques are applied, assessed, and improved for hydrogen enriched premixed and partially premixed gas-turbine combustion. Our innovative approaches include a completely consistent description of flame propagation; a coupled progress variable/level set method to resolve the detailed flame structure, and incorporation of thermal-diffusion (non-unity Lewis number) effects. In addition, we have developed a general flamelet-type transformation holding in the limits of both non-premixed and premixed burning. As a result, a model for partially premixed combustion has been derived. The coupled progress variable/level method and the general flamelet transformation were validated by LES of a lean-premixed low-swirl burner that has been studied experimentally at Lawrence Berkeley National Laboratory. The model is extended to include the non-unity Lewis number effects, which play a critical role in fuel-flexible combustor with high hydrogen content fuel. More specifically, a two-scalar model for lean hydrogen and hydrogen-enriched combustion is developed and validated against experimental and direct numerical simulation (DNS) data. Results are presented to emphasize the importance of non-unity Lewis number effects in the lean-premixed low-swirl burner of interest in this project. The proposed model gives improved results, which shows that the inclusion of the non-unity Lewis number effects is essential for accurate prediction of the lean-premixed low-swirl flame.

  10. The advanced computational testing and simulation toolkit (ACTS)

    International Nuclear Information System (INIS)

    During the past decades there has been a continuous growth in the number of physical and societal problems that have been successfully studied and solved by means of computational modeling and simulation. Distinctively, a number of these are important scientific problems ranging in scale from the atomic to the cosmic. For example, ionization is a phenomenon as ubiquitous in modern society as the glow of fluorescent lights and the etching on silicon computer chips; but it was not until 1999 that researchers finally achieved a complete numerical solution to the simplest example of ionization, the collision of a hydrogen atom with an electron. On the opposite scale, cosmologists have long wondered whether the expansion of the Universe, which began with the Big Bang, would ever reverse itself, ending the Universe in a Big Crunch. In 2000, analysis of new measurements of the cosmic microwave background radiation showed that the geometry of the Universe is flat, and thus the Universe will continue expanding forever. Both of these discoveries depended on high performance computer simulations that utilized computational tools included in the Advanced Computational Testing and Simulation (ACTS) Toolkit. The ACTS Toolkit is an umbrella project that brought together a number of general purpose computational tool development projects funded and supported by the U.S. Department of Energy (DOE). These tools, which have been developed independently, mainly at DOE laboratories, make it easier for scientific code developers to write high performance applications for parallel computers. They tackle a number of computational issues that are common to a large number of scientific applications, mainly implementation of numerical algorithms, and support for code development, execution and optimization. The ACTS Toolkit Project enables the use of these tools by a much wider community of computational scientists, and promotes code portability, reusability, reduction of duplicate efforts

  11. Advanced techniques for analytic liquid wastes management in the Rokkasho reprocessing plant

    International Nuclear Information System (INIS)

    The JNFS Rokkasho reprocessing plant is a large scale commercial reprocessing plant. Liquid waste treatment relies on concentration by evaporation. The management of liquid wastes is rather sophisticated and implies, beside the organic wastes, sorting out between process and non-process, acidic and salt-bearing, tritiated and low tritiated streams and also according to their level of activity. A particular attention had to be paid to the analytical wastes, as their particularity is to contain not only a significant amount of radioactivity but also some fissile material and exotic chemicals which are useful for analytical purpose but unwanted in the main process mainly because of their corrosive and chelating properties. The analytical wastes are sorted out according to their activity level and fissile material content. On the one hand, a specific process has been developed to recover the bulk of plutonium from the analytical wastes. On the other hand, the foreseeable amount of unwanted chemicals (such as chloride ions) has been drastically reduced by carefully selecting all the analytical methods either by modification of already known methods or in some cases by working out new methods

  12. Combining Semi-Analytic Models of Galaxy Formation with Simulations of Galaxy Clusters: the Need for AGN Heating

    CERN Document Server

    Short, C J

    2009-01-01

    We present hydrodynamical N-body simulations of clusters of galaxies with feedback taken from semi-analytic models of galaxy formation. The advantage of this technique is that the source of feedback in our simulations is a population of galaxies that closely resembles that found in the real universe. We demonstrate that, to achieve the high entropy levels found in clusters, active galactic nuclei must inject a large fraction of their energy into the intergalactic/intracluster media throughout the growth period of the central black hole. These simulations reinforce the argument of Bower et al. (2008), who arrived at the same conclusion on the basis of purely semi-analytic reasoning.

  13. Active-Learning Diabetes Simulation in an Advanced Pharmacy Practice Experience to Develop Patient Empathy

    OpenAIRE

    Whitley, Heather P.

    2012-01-01

    Objective. To develop and integrate an active-learning diabetes simulation into an advanced pharmacy practice experience to improve pharmacy students’ empathy toward patients with diabetes mellitus.

  14. ADVANCED TECHNIQUES FOR RESERVOIR SIMULATION AND MODELING OF NONCONVENTIONAL WELLS

    Energy Technology Data Exchange (ETDEWEB)

    Louis J. Durlofsky; Khalid Aziz

    2004-08-20

    Nonconventional wells, which include horizontal, deviated, multilateral and ''smart'' wells, offer great potential for the efficient management of oil and gas reservoirs. These wells are able to contact larger regions of the reservoir than conventional wells and can also be used to target isolated hydrocarbon accumulations. The use of nonconventional wells instrumented with downhole inflow control devices allows for even greater flexibility in production. Because nonconventional wells can be very expensive to drill, complete and instrument, it is important to be able to optimize their deployment, which requires the accurate prediction of their performance. However, predictions of nonconventional well performance are often inaccurate. This is likely due to inadequacies in some of the reservoir engineering and reservoir simulation tools used to model and optimize nonconventional well performance. A number of new issues arise in the modeling and optimization of nonconventional wells. For example, the optimal use of downhole inflow control devices has not been addressed for practical problems. In addition, the impact of geological and engineering uncertainty (e.g., valve reliability) has not been previously considered. In order to model and optimize nonconventional wells in different settings, it is essential that the tools be implemented into a general reservoir simulator. This simulator must be sufficiently general and robust and must in addition be linked to a sophisticated well model. Our research under this five year project addressed all of the key areas indicated above. The overall project was divided into three main categories: (1) advanced reservoir simulation techniques for modeling nonconventional wells; (2) improved techniques for computing well productivity (for use in reservoir engineering calculations) and for coupling the well to the simulator (which includes the accurate calculation of well index and the modeling of multiphase flow

  15. The development and application of advanced analytical methods to commercial ICF reactor chambers. Final report

    International Nuclear Information System (INIS)

    Progress is summarized in this report for each of the following tasks: (1) multi-dimensional radiation hydrodynamics computer code development; (2) 2D radiation-hydrodynamic code development; (3) ALARA: analytic and Laplacian adaptive radioactivity analysis -- a complete package for analysis of induced activation; (4) structural dynamics modeling of ICF reactor chambers; and (5) analysis of self-consistent target chamber clearing

  16. The development and application of advanced analytical methods to commercial ICF reactor chambers. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cousseau, P.; Engelstad, R.; Henderson, D.L. [and others

    1997-10-01

    Progress is summarized in this report for each of the following tasks: (1) multi-dimensional radiation hydrodynamics computer code development; (2) 2D radiation-hydrodynamic code development; (3) ALARA: analytic and Laplacian adaptive radioactivity analysis -- a complete package for analysis of induced activation; (4) structural dynamics modeling of ICF reactor chambers; and (5) analysis of self-consistent target chamber clearing.

  17. Recent Advances in the Analysis of Macromolecular Interactions Using the Matrix-Free Method of Sedimentation in the Analytical Ultracentrifuge

    Directory of Open Access Journals (Sweden)

    Stephen E. Harding

    2015-03-01

    Full Text Available Sedimentation in the analytical ultracentrifuge is a matrix free solution technique with no immobilisation, columns, or membranes required and can be used to study self-association and complex or “hetero”-interactions, stoichiometry, reversibility and interaction strength of a wide variety of macromolecular types and across a very large dynamic range (dissociation constants from 10−12 M to 10−1 M. We extend an earlier review specifically highlighting advances in sedimentation velocity and sedimentation equilibrium in the analytical ultracentrifuge applied to protein interactions and mucoadhesion and to review recent applications in protein self-association (tetanus toxoid, agrin, protein-like carbohydrate association (aminocelluloses, carbohydrate-protein interactions (polysaccharide-gliadin, nucleic-acid protein (G-duplexes, nucleic acid-carbohydrate (DNA-chitosan and finally carbohydrate-carbohydrate (xanthan-chitosan and a ternary polysaccharide complex interactions.

  18. Effect of methane co-injection in SAGD - analytical and simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Jyotsna; Moore, R.G.; Mehta, Raj [Society of Petroleum Engineers (Canada)

    2011-07-01

    Economical recovery of heavy oil and bitumen from reservoirs in Canada and elsewhere around the world is a major technical challenge. Most of the commonly used thermal oil recovery methods aim at reducing the viscosity of oil and enhancing its mobility by heating. Steam-assisted gravity drainage (SAGD) is a feasible recovery method for the Athabasca oil sands. In this study, a novel technique for injecting gas in SAGD is developed using an analytical model. This takes into account the three-phase flow of gas, oil and water in the reservoir. The paper presents the effects of methane co-injection in SAGD. The technique predicts relative permeability, saturation profiles, and fluid flow rates along with phase mobility in the mobile oil region. The results from this are replicated by fine grid numerical simulation. The results from the study also reveal that methane co-injection with steam is unfavorable in an SAGD process.

  19. Comparison of rheological analytic model with numerical simulation in powder injection molding filling process

    Institute of Scientific and Technical Information of China (English)

    刘跃军; 李祥刚; 黄宇刚; 魏珊珊; 曾广胜

    2008-01-01

    Mathematical model of filling disk-shaped mold cavity in steady state was studied.And the mathematical model under vibration field was developed from the model in steady state.According to the model of filling disk-shaped mold cavity in steady state,the filling time,the distribution of velocity field and the pressure field were obtained.The analysis results from rheological analytic model were compared with the numerical simulation results using Moldflow software in the powder injection molding filling process.Through the comparison,it is found that it is unreasonable to neglect the influence of temperature when calculated the pressure changing with the time at the cavity gate,while it can be neglected in other situations such as calculating the distribution of the velocity fields.This provides a theoretical reference for the establishment of correct model both in steady state and under vibration force field in the future.

  20. Simplified analytical model to simulate radionuclide release from radioactive waste trenches

    International Nuclear Information System (INIS)

    In order to evaluate postclosure off-site doses from low-level radioactive waste disposal facilities, a computer code was developed to simulate the radionuclide released from waste form, transport through vadose zone and transport in the saturated zone. This paper describes the methodology used to model these process. The radionuclide released from the waste is calculated using a model based on first order kinetics and the transport through porous media was determined using semi-analytical solution of the mass transport equation, considering the limiting case of unidirectional convective transport with three-dimensional dispersion in an isotropic medium. The results obtained in this work were compared with other codes, showing good agreement. (author)

  1. Advanced Simulation Capability for Environmental Management: Development and Demonstrations - 12532

    International Nuclear Information System (INIS)

    The U.S. Department of Energy Office of Environmental Management (EM), Technology Innovation and Development is supporting development of the Advanced Simulation Capability for Environmental Management (ASCEM). ASCEM is a state-of-the-art scientific tool and approach for understanding and predicting contaminant fate and transport in natural and engineered systems. The modular and open source high-performance computing tool facilitates integrated approaches to modeling and site characterization that enable robust and standardized assessments of performance and risk for EM cleanup and closure activities. The ASCEM project continues to make significant progress in development of capabilities, which are organized into Platform and Integrated Tool-sets and a High-Performance Computing Multi-process Simulator. The Platform capabilities target a level of functionality to allow end-to-end model development, starting with definition of the conceptual model and management of data for model input. The High-Performance Computing capabilities target increased functionality of process model representations, tool-sets for interaction with Platform, and verification and model confidence testing. The new capabilities are demonstrated through working groups, including one focused on the Hanford Site Deep Vadose Zone. The ASCEM program focused on planning during the first year and executing a prototype tool-set for an early demonstration of individual components. Subsequently, ASCEM has focused on developing and demonstrating an integrated set of capabilities, making progress toward a version of the capabilities that can be used to engage end users. Demonstration of capabilities continues to be implemented through working groups. Three different working groups, one focused on EM problems in the deep vadose zone, another investigating attenuation mechanisms for metals and radionuclides, and a third focusing on waste tank performance assessment, continue to make progress. The project

  2. Design and simulation of advanced charge recovery piezoactuator drivers

    International Nuclear Information System (INIS)

    The German Artificial Sphincter System project aims at the development of an implantable sphincter prosthesis driven by a piezoelectrically actuated micropump. The system has been designed to be fully implantable, i.e. the power supply is provided by a rechargeable lithium polymer battery. In order to provide sufficient battery duration and to limit battery dimensions, special effort has to be made to minimize power consumption of the whole system and, in particular, of the piezoactuator driver circuitry. Inductive charge recovery can be used to recover part of the charge stored within the actuator. We are going to present a simplified inductor-based circuit capable of voltage inversion across the actuator without the need of an additional negative voltage source. The dimension of the inductors required for such a concept is nevertheless significant. We therefore present a novel alternative concept, called direct switching, where the equivalent capacitance of the actuator is charged directly by a step-up converter and discharged by a step-down converter. We achieved superior performance compared to a simple inductor-based driver with the advantage of using small-size chip inductors. As a term of comparison, the performance of the aforementioned drivers is compared to a conventional driver that does not implement any charge recovery technique. With our design we have been able to achieve more than 50% reduction in power consumption compared to the simplest conventional driver. The new direct switching driver performs 15% better than an inductor-based driver. A novel, whole-system SPICE simulation is presented, where both the driving circuit and the piezoactuator are modeled making use of advanced nonlinear models. Such a simulation is a precious tool to design and optimize piezoactuator drivers

  3. GNU polyxmass: a software framework for mass spectrometric simulations of linear (bio-polymeric analytes

    Directory of Open Access Journals (Sweden)

    Rusconi Filippo

    2006-04-01

    Full Text Available Abstract Background Nowadays, a variety of (bio-polymers can be analyzed by mass spectrometry. The detailed interpretation of the spectra requires a huge number of "hypothesis cycles", comprising the following three actions 1 put forth a structural hypothesis, 2 test it, 3 (invalidate it. This time-consuming and painstaking data scrutiny is alleviated by using specialized software tools. However, all the software tools available to date are polymer chemistry-specific. This imposes a heavy overhead to researchers who do mass spectrometry on a variety of (bio-polymers, as each polymer type will require a different software tool to perform data simulations and analyses. We developed a software to address the lack of an integrated software framework able to deal with different polymer chemistries. Results The GNU polyxmass software framework performs common (bio-chemical simulations–along with simultaneous mass spectrometric calculations–for any kind of linear bio-polymeric analyte (DNA, RNA, saccharides or proteins. The framework is organized into three modules, all accessible from one single binary program. The modules let the user to 1 define brand new polymer chemistries, 2 perform quick mass calculations using a desktop calculator paradigm, 3 graphically edit polymer sequences and perform (bio-chemical/mass spectrometric simulations. Any aspect of the mass calculations, polymer chemistry reactions or graphical polymer sequence editing is configurable. Conclusion The scientist who uses mass spectrometry to characterize (bio-polymeric analytes of different chemistries is provided with a single software framework for his data prediction/analysis needs, whatever the polymer chemistry being involved.

  4. Extraction, Analytical and Advanced Methods for Detection of Allura Red AC (E129) in Food and Beverages Products

    Science.gov (United States)

    Rovina, Kobun; Siddiquee, Shafiquzzaman; Shaarani, Sharifudin M.

    2016-01-01

    Allura Red AC (E129) is an azo dye that widely used in drinks, juices, bakery, meat, and sweets products. High consumption of Allura Red has claimed an adverse effects of human health including allergies, food intolerance, cancer, multiple sclerosis, attention deficit hyperactivity disorder, brain damage, nausea, cardiac disease and asthma due to the reaction of aromatic azo compounds (R = R′ = aromatic). Several countries have banned and strictly controlled the uses of Allura Red in food and beverage products. This review paper is critically summarized on the available analytical and advanced methods for determination of Allura Red and also concisely discussed on the acceptable daily intake, toxicology and extraction methods. PMID:27303385

  5. Biochemical Technology Program progress report for the period January 1--June 30, 1976. [Centrifugal analyzers and advanced analytical systems for blood and body fluids

    Energy Technology Data Exchange (ETDEWEB)

    Mrochek, J.E.; Burtis, C.A.; Scott, C.D. (comps.)

    1976-09-01

    This document, which covers the period January 1-June 30, 1976, describes progress in the following areas: (1) advanced analytical techniques for the clinical laboratory, (2) fast clinical analyzers, (3) development of a miniaturized analytical clinical laboratory system, (4) centrifugal fast analyzers for animal toxicological studies, and (5) chemical profile of body fluids.

  6. Modeling and simulation challenges pursued by the Consortium for Advanced Simulation of Light Water Reactors (CASL)

    Science.gov (United States)

    Turinsky, Paul J.; Kothe, Douglas B.

    2016-05-01

    The Consortium for the Advanced Simulation of Light Water Reactors (CASL), the first Energy Innovation Hub of the Department of Energy, was established in 2010 with the goal of providing modeling and simulation (M&S) capabilities that support and accelerate the improvement of nuclear energy's economic competitiveness and the reduction of spent nuclear fuel volume per unit energy, and all while assuring nuclear safety. To accomplish this requires advances in M&S capabilities in radiation transport, thermal-hydraulics, fuel performance and corrosion chemistry. To focus CASL's R&D, industry challenge problems have been defined, which equate with long standing issues of the nuclear power industry that M&S can assist in addressing. To date CASL has developed a multi-physics "core simulator" based upon pin-resolved radiation transport and subchannel (within fuel assembly) thermal-hydraulics, capitalizing on the capabilities of high performance computing. CASL's fuel performance M&S capability can also be optionally integrated into the core simulator, yielding a coupled multi-physics capability with untapped predictive potential. Material models have been developed to enhance predictive capabilities of fuel clad creep and growth, along with deeper understanding of zirconium alloy clad oxidation and hydrogen pickup. Understanding of corrosion chemistry (e.g., CRUD formation) has evolved at all scales: micro, meso and macro. CFD R&D has focused on improvement in closure models for subcooled boiling and bubbly flow, and the formulation of robust numerical solution algorithms. For multiphysics integration, several iterative acceleration methods have been assessed, illuminating areas where further research is needed. Finally, uncertainty quantification and data assimilation techniques, based upon sampling approaches, have been made more feasible for practicing nuclear engineers via R&D on dimensional reduction and biased sampling. Industry adoption of CASL's evolving M

  7. Advances in classical and analytical mechanics: A reviews of author’s results

    Directory of Open Access Journals (Sweden)

    Hedrih-Stevanović Katica R.

    2013-01-01

    Full Text Available A review, in subjective choice, of author’s scientific results in area of: classical mechanics, analytical mechanics of discrete hereditary systems, analytical mechanics of discrete fractional order system vibrations, elastodynamics, nonlinear dynamics and hybrid system dynamics is presented. Main original author’s results were presented through the mathematical methods of mechanics with examples of applications for solving problems of mechanical real system dynamics abstracted to the theoretical models of mechanical discrete or continuum systems, as well as hybrid systems. Paper, also, presents serries of methods and scientific results authored by professors Mitropolyski, Andjelić and Rašković, as well as author’s of this paper original scientific research results obtained by methods of her professors. Vector method based on mass inertia moment vectors and corresponding deviational vector components for pole and oriented axis, defined in 1991 by K. Hedrih, is presented. Results in construction of analytical dynamics of hereditary discrete system obtained in collaboration with O. A. Gorosho are presented. Also, some selections of results author’s postgraduate students and doctorantes in area of nonlinear dynamics are presented. A list of scientific projects headed by author of this paper is presented with a list of doctoral dissertation and magister of sciences thesis which contain scientific research results obtained under the supervision by author of this paper or their fist doctoral candidates. [Projekat Ministarstva nauke Republike Srbije, br. ON174001: Dynamics of hybrid systems with complex structures

  8. The Vienna LTE-advanced simulators up and downlink, link and system level simulation

    CERN Document Server

    Rupp, Markus; Taranetz, Martin

    2016-01-01

    This book introduces the Vienna Simulator Suite for 3rd-Generation Partnership Project (3GPP)-compatible Long Term Evolution-Advanced (LTE-A) simulators and presents applications to demonstrate their uses for describing, designing, and optimizing wireless cellular LTE-A networks. Part One addresses LTE and LTE-A link level techniques. As there has been high demand for the downlink (DL) simulator, it constitutes the central focus of the majority of the chapters. This part of the book reports on relevant highlights, including single-user (SU), multi-user (MU) and single-input-single-output (SISO) as well as multiple-input-multiple-output (MIMO) transmissions. Furthermore, it summarizes the optimal pilot pattern for high-speed communications as well as different synchronization issues. One chapter is devoted to experiments that show how the link level simulator can provide input to a testbed. This section also uses measurements to present and validate fundamental results on orthogonal frequency division multiple...

  9. Analytic fitting and simulation methods for characteristic X-ray peaks from Si-PIN detector

    International Nuclear Information System (INIS)

    A semi-empirical detector response function (DRF) model is established to fit characteristic X-ray peaks recorded in Si-PIN spectra, which is mainly composed of four components: a truncated step function, a Gaussian-shaped full-energy peak, a Gaussian-shaped Si escape peak and an exponential tail. A simple but useful statistical distribution-based analytic method (SDA) is proposed to achieve accurate values of standard deviation for characteristic X-ray peaks. And the values of the model parameters except for the standard deviation are obtained by weighted least-squares fitting of the pulse-height spectra from a number of pure-element samples. A Monte Carlo model is also established to simulate the X-ray measurement setup. The simulated flux spectrum can be transformed by Si-PIN detector response function to real pulse height spectrum as studied in this work. Finally, the fitting result for a copper alloy sample was compared with experimental spectra, and the validity of the present method was demonstrated. (authors)

  10. Analytical simulation of nonlinear response to seismic test excitations of HDR-VKL piping system

    International Nuclear Information System (INIS)

    Dynamic tests with simulated earthquake excitation (SHAM) were performed during April--May 1988 on the Versuchskreislauf (VKL) piping system at the Heissdampfreaktor (HDR) Test Facility in Kahl/Main, Federal Republic of Germany. The major objectives of these tests were to study the behavior of a full-scale in-plant piping system subjected to a range of seismic excitation levels (from design levels to those that might induce either failure of pipe supports or plasticity in the pipe runs) and to establish seismic margins for piping and pipe supports. Data obtained in the tests are also being used to validate analytical methods for piping response calculation. Detailed reports on the SHAM experiments are given elsewhere by Kot et al. (1990). This paper describes an effort to evaluate the computer code NONPIPE (proprietary to Nutech Engineers) with data from one of the SHAM tests. NONPIPE is a nonlinear finite-element program capable of calculating the elastic-plastic response of piping systems subjected to seismic excitation. The special characteristic of this code is the simplified or approximate approach it uses for modeling the elastic behavior which makes the calculations relatively less resource intensive than those of other nonlinear codes. The evaluation is based on a comparison of computational results of simulation of a SHAM test with corresponding test measurements. 6 refs., 10 figs

  11. Utility-Analytic Approach and Swarm Simulations of Security Policies in Digital Rights Management

    Directory of Open Access Journals (Sweden)

    Zhiyong Zhang

    2010-10-01

    Full Text Available DRM (Digital Rights Management Ecosystem to date lacks of a multi-participant trust for stakeholders, which are involved in Contents Provider, Rights Provider and End User, as has significantly negative impacts on DRM-enabled contents value chain's survivable. In order to establish the trust, a utility-analytic and non-cooperative game approach to the optimal adoption of cost-effective security policies was employed. A series of Swarm-based simulation experiments were highlighted, both considering a generic DRM application scenario on the contents acquisition, and discussing different sharing modes' influences on the adoption strategies of typical security policies for a much more complicated scenario on the contents sharing. The simulation results manifest that the enhanced security policies combination are not necessarily rational under any circumstance for the former scenario, and the optimal combination and its precondition are represented. Besides, the best modest sharing mode would spur consumer and contents provider to earn the maximum benefits, as is based on the given optimal security policies profile.

  12. Natural frequencies of two bubbles in a compliant tube: Analytical, simulation, and experimental results

    Science.gov (United States)

    Jang, Neo W.; Zakrzewski, Aaron; Rossi, Christina; Dalecki, Diane; Gracewski, Sheryl

    2011-01-01

    Motivated by various clinical applications of ultrasound contrast agents within blood vessels, the natural frequencies of two bubbles in a compliant tube are studied analytically, numerically, and experimentally. A lumped parameter model for a five degree of freedom system was developed, accounting for the compliance of the tube and coupled response of the two bubbles. The results were compared to those produced by two different simulation methods: (1) an axisymmetric coupled boundary element and finite element code previously used to investigate the response of a single bubble in a compliant tube and (2) finite element models developed in comsol Multiphysics. For the simplified case of two bubbles in a rigid tube, the lumped parameter model predicts two frequencies for in- and out-of-phase oscillations, in good agreement with both numerical simulation and experimental results. For two bubbles in a compliant tube, the lumped parameter model predicts four nonzero frequencies, each asymptotically converging to expected values in the rigid and compliant limits of the tube material. PMID:22088008

  13. A novel fast and accurate pseudo-analytical simulation approach for MOAO

    KAUST Repository

    Gendron, É.

    2014-08-04

    Multi-object adaptive optics (MOAO) is a novel adaptive optics (AO) technique for wide-field multi-object spectrographs (MOS). MOAO aims at applying dedicated wavefront corrections to numerous separated tiny patches spread over a large field of view (FOV), limited only by that of the telescope. The control of each deformable mirror (DM) is done individually using a tomographic reconstruction of the phase based on measurements from a number of wavefront sensors (WFS) pointing at natural and artificial guide stars in the field. We have developed a novel hybrid, pseudo-analytical simulation scheme, somewhere in between the end-to- end and purely analytical approaches, that allows us to simulate in detail the tomographic problem as well as noise and aliasing with a high fidelity, and including fitting and bandwidth errors thanks to a Fourier-based code. Our tomographic approach is based on the computation of the minimum mean square error (MMSE) reconstructor, from which we derive numerically the covariance matrix of the tomographic error, including aliasing and propagated noise. We are then able to simulate the point-spread function (PSF) associated to this covariance matrix of the residuals, like in PSF reconstruction algorithms. The advantage of our approach is that we compute the same tomographic reconstructor that would be computed when operating the real instrument, so that our developments open the way for a future on-sky implementation of the tomographic control, plus the joint PSF and performance estimation. The main challenge resides in the computation of the tomographic reconstructor which involves the inversion of a large matrix (typically 40 000 × 40 000 elements). To perform this computation efficiently, we chose an optimized approach based on the use of GPUs as accelerators and using an optimized linear algebra library: MORSE providing a significant speedup against standard CPU oriented libraries such as Intel MKL. Because the covariance matrix is

  14. Advanced Simulation Capability for Environmental Management (ASCEM) Phase II Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Freshley, M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hubbard, S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Flach, G. [Savannah River National Lab. (SRNL), Aiken, SC (United States); Freedman, V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Agarwal, D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Andre, B. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bott, Y. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chen, X. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Davis, J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Faybishenko, B. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gorton, I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Murray, C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Moulton, D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Meyer, J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rockhold, M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Shoshani, A. [LBNL; Steefel, C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wainwright, H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Waichler, S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2012-09-28

    In 2009, the National Academies of Science (NAS) reviewed and validated the U.S. Department of Energy Office of Environmental Management (EM) Technology Program in its publication, Advice on the Department of Energy’s Cleanup Technology Roadmap: Gaps and Bridges. The NAS report outlined prioritization needs for the Groundwater and Soil Remediation Roadmap, concluded that contaminant behavior in the subsurface is poorly understood, and recommended further research in this area as a high priority. To address this NAS concern, the EM Office of Site Restoration began supporting the development of the Advanced Simulation Capability for Environmental Management (ASCEM). ASCEM is a state-of-the-art scientific approach that uses an integration of toolsets for understanding and predicting contaminant fate and transport in natural and engineered systems. The ASCEM modeling toolset is modular and open source. It is divided into three thrust areas: Multi-Process High Performance Computing (HPC), Platform and Integrated Toolsets, and Site Applications. The ASCEM toolsets will facilitate integrated approaches to modeling and site characterization that enable robust and standardized assessments of performance and risk for EM cleanup and closure activities. During fiscal year 2012, the ASCEM project continued to make significant progress in capabilities development. Capability development occurred in both the Platform and Integrated Toolsets and Multi-Process HPC Simulator areas. The new Platform and Integrated Toolsets capabilities provide the user an interface and the tools necessary for end-to-end model development that includes conceptual model definition, data management for model input, model calibration and uncertainty analysis, and model output processing including visualization. The new HPC Simulator capabilities target increased functionality of process model representations, toolsets for interaction with the Platform, and model confidence testing and verification for

  15. Electromagnetic wave theory for boundary-value problems an advanced course on analytical methods

    CERN Document Server

    Eom, Hyo J

    2004-01-01

    Electromagnetic wave theory is based on Maxwell's equations, and electromagnetic boundary-value problems must be solved to understand electromagnetic scattering, propagation, and radiation. Electromagnetic theory finds practical applications in wireless telecommunications and microwave engineering. This book is written as a text for a two-semester graduate course on electromagnetic wave theory. As such, Electromagnetic Wave Theory for Boundary-Value Problems is intended to help students enhance analytic skills by solving pertinent boundary-value problems. In particular, the techniques of Fourier transform, mode matching, and residue calculus are utilized to solve some canonical scattering and radiation problems.

  16. Editorial: Advances in Health Education Applying E-Learning, Simulations and Distance Technologies

    OpenAIRE

    Andre W. Kushniruk (ACMI Fellow; CAHS Fellow)

    2011-01-01

    This special issue of the KM&EL international journal is dedicated to coverage of novel advances in health professional education applying e-Learning, simulations and distance education technologies. Modern healthcare is beginning to be transformed through the emergence of new information technologies and rapid advances in health informatics. Advances such as electronic health record systems (EHRs), clinical decision support systems and other advanced information systems such as public health...

  17. Overview of the Consortium for the Advanced Simulation of Light Water Reactors (CASL)

    OpenAIRE

    Kulesza Joel A.; Franceschini Fausto; Evans Thomas M.; Gehin Jess C.

    2016-01-01

    The Consortium for Advanced Simulation of Light Water Reactors (CASL) was established in July 2010 for the purpose of providing advanced modeling and simulation solutions for commercial nuclear reactors. The primary goal is to provide coupled, higher-fidelity, usable modeling and simulation capabilities than are currently available. These are needed to address light water reactor (LWR) operational and safety performance-defining phenomena that are not yet able to be fully modeled taking a fir...

  18. Numerical hydrodynamic simulations based on semi-analytic galaxy merger trees: method and Milky-Way like galaxies

    CERN Document Server

    Moster, Benjamin P; Somerville, Rachel S

    2012-01-01

    We present a new approach to study galaxy evolution in a cosmological context. We combine cosmological merger trees and semi-analytic models of galaxy formation to provide the initial conditions for multi-merger hydrodynamic simulations. In this way we exploit the advantages of merger simulations (high resolution and inclusion of the gas physics) and semi-analytic models (cosmological background and low computational cost), and integrate them to create a novel tool. This approach allows us to study the evolution of various galaxy properties, including the treatment of the hot gaseous halo from which gas cools and accretes onto the central disc, which has been neglected in many previous studies. This method shows several advantages over other methods. As only the particles in the regions of interest are included, the run time is much shorter than in traditional cosmological simulations, leading to greater computational efficiency. Using cosmological simulations, we show that multiple mergers are expected to be...

  19. Advances in Microfluidic Paper-Based Analytical Devices for Food and Water Analysis

    Directory of Open Access Journals (Sweden)

    Lori Shayne Alamo Busa

    2016-05-01

    Full Text Available Food and water contamination cause safety and health concerns to both animals and humans. Conventional methods for monitoring food and water contamination are often laborious and require highly skilled technicians to perform the measurements, making the quest for developing simpler and cost-effective techniques for rapid monitoring incessant. Since the pioneering works of Whitesides’ group from 2007, interest has been strong in the development and application of microfluidic paper-based analytical devices (μPADs for food and water analysis, which allow easy, rapid and cost-effective point-of-need screening of the targets. This paper reviews recently reported μPADs that incorporate different detection methods such as colorimetric, electrochemical, fluorescence, chemiluminescence, and electrochemiluminescence techniques for food and water analysis.

  20. PROBING THE ROLE OF DYNAMICAL FRICTION IN SHAPING THE BSS RADIAL DISTRIBUTION. I. SEMI-ANALYTICAL MODELS AND PRELIMINARY N-BODY SIMULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Miocchi, P.; Lanzoni, B.; Ferraro, F. R.; Dalessandro, E.; Alessandrini, E. [Dipartimento di Fisica e Astronomia, Università di Bologna, Viale Berti Pichat 6/2, I-40127 Bologna (Italy); Pasquato, M.; Lee, Y.-W. [Department of Astronomy and Center for Galaxy Evolution Research, Yonsei University, Seoul 120-749 (Korea, Republic of); Vesperini, E. [Department of Astronomy, Indiana University, Bloomington, IN 47405 (United States)

    2015-01-20

    We present semi-analytical models and simplified N-body simulations with 10{sup 4} particles aimed at probing the role of dynamical friction (DF) in determining the radial distribution of blue straggler stars (BSSs) in globular clusters. The semi-analytical models show that DF (which is the only evolutionary mechanism at work) is responsible for the formation of a bimodal distribution with a dip progressively moving toward the external regions of the cluster. However, these models fail to reproduce the formation of the long-lived central peak observed in all dynamically evolved clusters. The results of N-body simulations confirm the formation of a sharp central peak, which remains as a stable feature over time regardless of the initial concentration of the system. In spite of noisy behavior, a bimodal distribution forms in many cases, with the size of the dip increasing as a function of time. In the most advanced stages, the distribution becomes monotonic. These results are in agreement with the observations. Also, the shape of the peak and the location of the minimum (which, in most of cases, is within 10 core radii) turn out to be consistent with observational results. For a more detailed and close comparison with observations, including a proper calibration of the timescales of the dynamical processes driving the evolution of the BSS spatial distribution, more realistic simulations will be necessary.

  1. Analytic analysis of LTE/LTE-Advanced power saving and delay with bursty traffic

    OpenAIRE

    Bhamber, R. S.; Fowler, Scott; Braimiotis, C.; Mellouk, A.

    2013-01-01

    The 4G standard Long Term Evolution (LTE) has been developed for high-bandwidth mobile access for today’s data-heavy applications. However, these data-heavy applications require lots of battery power on the user equipment. To extend the user equipment battery lifetime, plus further support various services and large amount of data transmissions, the 3GPP standards for LTE/LTE-Advanced has adopted discontinuous reception (DRX). In this paper, we take an overview of various static/fixed DRX cyc...

  2. Discrete event simulation methods applied to advanced importance measures of repairable components in multistate network flow systems

    International Nuclear Information System (INIS)

    Discrete event models are frequently used in simulation studies to model and analyze pure jump processes. A discrete event model can be viewed as a system consisting of a collection of stochastic processes, where the states of the individual processes change as results of various kinds of events occurring at random points of time. We always assume that each event only affects one of the processes. Between these events the states of the processes are considered to be constant. In the present paper we use discrete event simulation in order to analyze a multistate network flow system of repairable components. In order to study how the different components contribute to the system, it is necessary to describe the often complicated interaction between component processes and processes at the system level. While analytical considerations may throw some light on this, a simulation study often allows the analyst to explore more details. By producing stable curve estimates for the development of the various processes, one gets a much better insight in how such systems develop over time. These methods are particulary useful in the study of advanced importancez measures of repairable components. Such measures can be very complicated, and thus impossible to calculate analytically. By using discrete event simulations, however, this can be done in a very natural and intuitive way. In particular significant differences between the Barlow–Proschan measure and the Natvig measure in multistate network flow systems can be explored

  3. A combined approach of simulation and analytic hierarchy process in assessing production facility layouts

    Science.gov (United States)

    Ramli, Razamin; Cheng, Kok-Min

    2014-07-01

    One of the important areas of concern in order to obtain a competitive level of productivity in a manufacturing system is the layout design and material transportation system (conveyor system). However, changes in customers' requirements have triggered the need to design other alternatives of the manufacturing layout for existing production floor. Hence, this paper discusses effective alternatives of the process layout specifically, the conveyor system layout. Subsequently, two alternative designs for the conveyor system were proposed with the aims to increase the production output and minimize space allocation. The first proposed layout design includes the installation of conveyor oven in the particular manufacturing room based on priority, and the second one is the one without the conveyor oven in the layout. Simulation technique was employed to design the new facility layout. Eventually, simulation experiments were conducted to understand the performance of each conveyor layout design based on operational characteristics, which include predicting the output of layouts. Utilizing the Analytic Hierarchy Process (AHP), the newly and improved layout designs were assessed before the final selection was done. As a comparison, the existing conveyor system layout was included in the assessment process. Relevant criteria involved in this layout design problem were identified as (i) usage of space of each design, (ii) operator's utilization rates, (iii) return of investment (ROI) of the layout, and (iv) output of the layout. In the final stage of AHP analysis, the overall priority of each alternative layout was obtained and thus, a selection for final use by the management was made based on the highest priority value. This efficient planning and designing of facility layout in a particular manufacturing setting is able to minimize material handling cost, minimize overall production time, minimize investment in equipment, and optimize utilization of space.

  4. Advanced nanoelectronics

    CERN Document Server

    Ismail, Razali

    2012-01-01

    While theories based on classical physics have been very successful in helping experimentalists design microelectronic devices, new approaches based on quantum mechanics are required to accurately model nanoscale transistors and to predict their characteristics even before they are fabricated. Advanced Nanoelectronics provides research information on advanced nanoelectronics concepts, with a focus on modeling and simulation. Featuring contributions by researchers actively engaged in nanoelectronics research, it develops and applies analytical formulations to investigate nanoscale devices. The

  5. A carrier-based analytical theory for negative capacitance symmetric double-gate field effect transistors and its simulation verification

    Science.gov (United States)

    Jiang, Chunsheng; Liang, Renrong; Wang, Jing; Xu, Jun

    2015-09-01

    A carrier-based analytical drain current model for negative capacitance symmetric double-gate field effect transistors (NC-SDG FETs) is proposed by solving the differential equation of the carrier, the Pao-Sah current formulation, and the Landau-Khalatnikov equation. The carrier equation is derived from Poisson’s equation and the Boltzmann distribution law. According to the model, an amplified semiconductor surface potential and a steeper subthreshold slope could be obtained with suitable thicknesses of the ferroelectric film and insulator layer at room temperature. Results predicted by the analytical model agree well with those of the numerical simulation from a 2D simulator without any fitting parameters. The analytical model is valid for all operation regions and captures the transitions between them without any auxiliary variables or functions. This model can be used to explore the operating mechanisms of NC-SDG FETs and to optimize device performance.

  6. A carrier-based analytical theory for negative capacitance symmetric double-gate field effect transistors and its simulation verification

    International Nuclear Information System (INIS)

    A carrier-based analytical drain current model for negative capacitance symmetric double-gate field effect transistors (NC-SDG FETs) is proposed by solving the differential equation of the carrier, the Pao-Sah current formulation, and the Landau–Khalatnikov equation. The carrier equation is derived from Poisson’s equation and the Boltzmann distribution law. According to the model, an amplified semiconductor surface potential and a steeper subthreshold slope could be obtained with suitable thicknesses of the ferroelectric film and insulator layer at room temperature. Results predicted by the analytical model agree well with those of the numerical simulation from a 2D simulator without any fitting parameters. The analytical model is valid for all operation regions and captures the transitions between them without any auxiliary variables or functions. This model can be used to explore the operating mechanisms of NC-SDG FETs and to optimize device performance. (paper)

  7. Shake table tests and analytical simulations of a steel structure with shape memory alloy dampers

    International Nuclear Information System (INIS)

    This study uses the pseudoelastic properties of Ni–Ti shape memory alloy wires for attenuation of the seismic response of a steel structure and evaluates its effectiveness and applicability in seismic response control. In this paper, shake table tests, carried out on a model of a steel structure with and without wire-based shape memory alloy dampers, are discussed in detail. Shake table tests, comprised of free vibration tests and spectrum compatible time history tests, were carried out. The former were used for the evaluation of the frequency and damping, and the later were used to prove the efficacy of the shape memory alloy dampers. Further analytical simulations are carried out using detailed time history analysis utilizing a thermomechanical model of an SMA and taking into account the residual martensite accumulation, which is irreversibly due to cyclic forward/reverse martensitic transformation. Moreover, a simple iterative response spectrum (IRS) method with equivalent damping and stiffness is also used to evaluate the response of the structure with SMA dampers, and it is proved that the method can be conservatively used by designers. (paper)

  8. Earthquake simulation, actual earthquake monitoring and analytical methods for soil-structure interaction investigation

    International Nuclear Information System (INIS)

    Approaches for conducting in-situ soil-structure interaction experiments are discussed. High explosives detonated under the ground can generate strong ground motion to induce soil-structure interaction (SSI). The explosive induced data are useful in studying the dynamic characteristics of the soil-structure system associated with the inertial aspect of the SSI problem. The plane waves generated by the explosives cannot adequately address the kinematic interaction associated with actual earthquakes because of he difference in wave fields and their effects. Earthquake monitoring is ideal for obtaining SSI data that can address all aspects of the SSI problem. The only limitation is the level of excitation that can be obtained. Neither the simulated earthquake experiments nor the earthquake monitoring experiments can have exact similitude if reduced scale test structures are used. If gravity effects are small, reasonable correlations between the scaled model and the prototype can be obtained provided that input motion can be scaled appropriately. The key product of the in-situ experiments is the data base that can be used to qualify analytical methods for prototypical applications. (author)

  9. Semi-analytic Simulations of Galactic Winds: Volume Filling Factor, Ejection of Metals and Parameter Study

    CERN Document Server

    Bertone, S; White, S D M; Bertone, Serena; Stoehr, Felix; White, Simon D. M.

    2004-01-01

    We present a semi-analytic treatment of galactic winds within high resolution, large scale cosmological N-body simulations of a LCDM Universe. The evolution of winds is investigated by following the expansion of supernova driven supershells around the several hundred thousand galaxies that form in an approximately spherical region of space with diameter 52 Mpc/h and mean density close to the mean density of the Universe. We focus our attention on the impact of winds on the diffuse intergalactic medium. Initial conditions for mass loss at the base of winds are taken from Shu, Mo and Mao (2003). Results are presented for the volume filling factor and the mass fraction of IGM in winds and their dependence on the model parameters is carefully investigated. We find that a high volume filling factor does not necessarily correspond to a high mass fraction in wind shells, implying that even very spatially extended galactic winds may not leave detectable imprints on the Lyalpha forest. Low mass galaxies play a major r...

  10. Analytical and Neural Network Models for Gas Turbine Design and Off-Design Simulation

    Directory of Open Access Journals (Sweden)

    Andrea Toffolo

    2001-12-01

    Full Text Available

    This paper presents a gas turbine design and off-design model in which the difficulties due to lack of knowledge about stage-by-stage performance are overcome by constructing artificial machine maps through appropriate scaling techniques applied to generalized maps taken from the literature and validating them with test measurement data from real plants. In particular, off-design performance is obtained through compressor map modifications according to variable inlet guide vane closure. The set of equations of the developed analytical model is solved by a commercial package, which provides great flexibility in the choice of independent variables of the overall system. The results obtained from this simulator are used for neural network training: problems associated with the construction and use of neural networks are discussed and their capability as a tool for predicting machine performance is analyzed.

    • This paper was presented at the ECOS'01 Conference in Turkey, July 4-6, 2001 and revised 

  11. Harmonic oscillator in heat bath: Exact simulation of time-lapse-recorded data and exact analytical benchmark statistics

    DEFF Research Database (Denmark)

    Nørrelykke, Simon F; Flyvbjerg, Henrik

    2011-01-01

    The stochastic dynamics of the damped harmonic oscillator in a heat bath is simulated with an algorithm that is exact for time steps of arbitrary size. Exact analytical results are given for correlation functions and power spectra in the form they acquire when computed from experimental time-laps...

  12. Harmonic oscillator in heat bath: Exact simulation of time-lapse-recorded data and exact analytical benchmark statistics

    DEFF Research Database (Denmark)

    Nørrelykke, Simon F; Flyvbjerg, Henrik

    2011-01-01

    The stochastic dynamics of the damped harmonic oscillator in a heat bath is simulated with an algorithm that is exact for time steps of arbitrary size. Exact analytical results are given for correlation functions and power spectra in the form they acquire when computed from experimental time...

  13. Advanced organic analysis and analytical methods development: FY 1995 progress report. Waste Tank Organic Safety Program

    Energy Technology Data Exchange (ETDEWEB)

    Wahl, K.L.; Campbell, J.A.; Clauss, S.A. [and others

    1995-09-01

    This report describes the work performed during FY 1995 by Pacific Northwest Laboratory in developing and optimizing analysis techniques for identifying organics present in Hanford waste tanks. The main focus was to provide a means for rapidly obtaining the most useful information concerning the organics present in tank waste, with minimal sample handling and with minimal waste generation. One major focus has been to optimize analytical methods for organic speciation. Select methods, such as atmospheric pressure chemical ionization mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometry, were developed to increase the speciation capabilities, while minimizing sample handling. A capillary electrophoresis method was developed to improve separation capabilities while minimizing additional waste generation. In addition, considerable emphasis has been placed on developing a rapid screening tool, based on Raman and infrared spectroscopy, for determining organic functional group content when complete organic speciation is not required. This capability would allow for a cost-effective means to screen the waste tanks to identify tanks that require more specialized and complete organic speciation to determine tank safety.

  14. Advanced organic analysis and analytical methods development: FY 1995 progress report. Waste Tank Organic Safety Program

    International Nuclear Information System (INIS)

    This report describes the work performed during FY 1995 by Pacific Northwest Laboratory in developing and optimizing analysis techniques for identifying organics present in Hanford waste tanks. The main focus was to provide a means for rapidly obtaining the most useful information concerning the organics present in tank waste, with minimal sample handling and with minimal waste generation. One major focus has been to optimize analytical methods for organic speciation. Select methods, such as atmospheric pressure chemical ionization mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometry, were developed to increase the speciation capabilities, while minimizing sample handling. A capillary electrophoresis method was developed to improve separation capabilities while minimizing additional waste generation. In addition, considerable emphasis has been placed on developing a rapid screening tool, based on Raman and infrared spectroscopy, for determining organic functional group content when complete organic speciation is not required. This capability would allow for a cost-effective means to screen the waste tanks to identify tanks that require more specialized and complete organic speciation to determine tank safety

  15. Advanced analytical techniques for the extraction and characterization of plant-derived essential oils by gas chromatography with mass spectrometry.

    Science.gov (United States)

    Waseem, Rabia; Low, Kah Hin

    2015-02-01

    In recent years, essential oils have received a growing interest because of the positive health effects of their novel characteristics such as antibacterial, antifungal, and antioxidant activities. For the extraction of plant-derived essential oils, there is the need of advanced analytical techniques and innovative methodologies. An exhaustive study of hydrodistillation, supercritical fluid extraction, ultrasound- and microwave-assisted extraction, solid-phase microextraction, pressurized liquid extraction, pressurized hot water extraction, liquid-liquid extraction, liquid-phase microextraction, matrix solid-phase dispersion, and gas chromatography (one- and two-dimensional) hyphenated with mass spectrometry for the extraction through various plant species and analysis of essential oils has been provided in this review. Essential oils are composed of mainly terpenes and terpenoids with low-molecular-weight aromatic and aliphatic constituents that are particularly important for public health. PMID:25403494

  16. Using Simulated Debates to Teach History of Engineering Advances

    Science.gov (United States)

    Reynolds, Terry S.

    1976-01-01

    Described is a technique for utilizing debates of past engineering controversies in the classroom as a means of teaching the history of engineering advances. Included is a bibliography for three debate topics relating to important controversies. (SL)

  17. Experimental and analytical studies of a passive shutdown heat removal system for advanced LMRs

    International Nuclear Information System (INIS)

    A facility designed and constructed to demonstrate the viability of natural convection passive heat removal systems as a key feature of innovative LMR Shutdown Heat Removal (SHR) systems is in operation at Argonne National Laboratory (ANL). This Natural Convection Shutdown Heat Removal Test Facility (NSTF) is being used to investigate the heat transfer performance of the GE/PRISM and the RI/SAFR passive designs. This paper presents a description of the NSTF, the pretest analysis of the Radiant Reactor Vessel Auxiliary Cooling System (RVACS) in support of the GE/PRISM IFR concept, and experiment results for the RVACS simulation. Preliminary results show excellent agreement with predicted system performance

  18. Advances in Computational Social Science and Social Simulation

    OpenAIRE

    Miguel Quesada, Francisco J.; Amblard, Frédéric; Juan A. Barceló; Madella, Marco; Aguirre, Cristián; Ahrweiler, Petra; Aldred, Rachel; Ali Abbas, Syed Muhammad; Lopez Rojas, Edgar Alonso; Alonso Betanzos, Amparo; Alvarez Galvez, Javier; Andrighetto, Giulia; Antunes, Luis; Araghi, Yashar; Asatani, Kimitaka

    2014-01-01

    Aquesta conferència és la celebració conjunta de la "10th Artificial Economics Conference AE", la "10th Conference of the European Social Simulation Association ESSA" i la "1st Simulating the Past to Understand Human History SPUHH". Conferència organitzada pel Laboratory for Socio­-Historical Dynamics Simulation (LSDS-­UAB) de la Universitat Autònoma de Barcelona. Readers will find results of recent research on computational social science and social simulation economics, management, so...

  19. Non-dissipative kinetic simulation and analytical solution of three-mode equations of ion temperature gradient instability

    International Nuclear Information System (INIS)

    A non-dissipative drift kinetic simulation scheme, which rigorously satisfies the time-reversibility, is applied to the three-mode coupling problem of the ion temperature gradient (ITG) instability. It is found from the simulation that the three-mode ITG system repeats growth and decay with a period which shows a logarithmic divergence for infinitesimal initial perturbations. Accordingly, time average of the mode amplitude vanishes, as the initial amplitude approaches to zero. An exact solution is analytically given for a class of initial conditions. An excellent agreement is confirmed between the analytical solution and numerical results. The results obtained here provide a useful reference for basic benchmarking of theories and simulation of the ITG modes. (author)

  20. Vision and Displays for Military and Security Applications The Advanced Deployable Day/Night Simulation Project

    CERN Document Server

    Niall, Keith K

    2010-01-01

    Vision and Displays for Military and Security Applications presents recent advances in projection technologies and associated simulation technologies for military and security applications. Specifically, this book covers night vision simulation, semi-automated methods in photogrammetry, and the development and evaluation of high-resolution laser projection technologies for simulation. Topics covered include: advances in high-resolution projection, advances in image generation, geographic modeling, and LIDAR imaging, as well as human factors research for daylight simulation and for night vision devices. This title is ideal for optical engineers, simulator users and manufacturers, geomatics specialists, human factors researchers, and for engineers working with high-resolution display systems. It describes leading-edge methods for human factors research, and it describes the manufacture and evaluation of ultra-high resolution displays to provide unprecedented pixel density in visual simulation.

  1. ALICES: advanced software engineering workshop for real-time simulators

    Energy Technology Data Exchange (ETDEWEB)

    Noel, A.; Rouault, G. [Tractebel, Brussels (Belgium)

    1997-12-01

    The ALICES software workshop is presently being applied for the development of a multifunctional simulator for Belgium`s Tihange-1 nuclear power unit. This will be the best validation for all the functions included in the tools. It is believed that ALICES will permit the development of quality realtime simulators at a significantly lower price.

  2. Probing the role of dynamical friction in shaping the BSS radial distribution. I - Semi-analytical models and preliminary N-body simulations

    CERN Document Server

    Miocchi, P; Lanzoni, B; Ferraro, F R; Dalessandro, E; Vesperini, E; Alessandrini, E; Lee, Y W

    2014-01-01

    We present semi-analytical models and simplified $N$-body simulations with $10^4$ and $10^5$ particles aimed at probing the role of dynamical friction (DF) in determining the radial distribution of Blue Straggler Stars (BSSs) in globular clusters. The semi-analytical models show that DF (which is the only evolutionary mechanism at work) is responsible for the formation of a bimodal distribution with a dip progressively moving toward the external regions of the cluster. However, these models fail to reproduce the formation of the long-lived central peak observed in all dynamically evolved clusters. The results of $N$-body simulations confirm the formation of a sharp central peak, which remains as a stable feature over the time regardless of the initial concentration of the system. In spite of a noisy behavior, a bimodal distribution forms in many cases, with the size of the dip increasing as a function of time. In the most advanced stages the distribution becomes monotonic. These results are in agreement with ...

  3. Development of Kinetic Mechanisms for Next-Generation Fuels and CFD Simulation of Advanced Combustion Engines

    Energy Technology Data Exchange (ETDEWEB)

    Pitz, William J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McNenly, Matt J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Whitesides, Russell [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mehl, Marco [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Killingsworth, Nick J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Westbrook, Charles K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-12-17

    Predictive chemical kinetic models are needed to represent next-generation fuel components and their mixtures with conventional gasoline and diesel fuels. These kinetic models will allow the prediction of the effect of alternative fuel blends in CFD simulations of advanced spark-ignition and compression-ignition engines. Enabled by kinetic models, CFD simulations can be used to optimize fuel formulations for advanced combustion engines so that maximum engine efficiency, fossil fuel displacement goals, and low pollutant emission goals can be achieved.

  4. Advanced Algebraic Multigrid Solvers for Subsurface Flow Simulation

    KAUST Repository

    Chen, Meng-Huo

    2015-09-13

    In this research we are particularly interested in extending the robustness of multigrid solvers to encounter complex systems related to subsurface reservoir applications for flow problems in porous media. In many cases, the step for solving the pressure filed in subsurface flow simulation becomes a bottleneck for the performance of the simulator. For solving large sparse linear system arising from MPFA discretization, we choose multigrid methods as the linear solver. The possible difficulties and issues will be addressed and the corresponding remedies will be studied. As the multigrid methods are used as the linear solver, the simulator can be parallelized (although not trivial) and the high-resolution simulation become feasible, the ultimately goal which we desire to achieve.

  5. Development and implementation of advanced control methods for hybrid simulation

    OpenAIRE

    Kim, Hong

    2011-01-01

    Hybrid simulation is an effective way of testing structures that combines the benefits of a computational analysis and experimental testing techniques. Innovative structures consists of state-ofthe-art components and assemblages whose function as a system needs to be tested experimentally. Often times, these components and assemblages push the controller and other testing equipment to its limits. Performing hybrid simulation with the controller in displacement control mode does not always suf...

  6. Advance Reservation based DAG Application Scheduling Simulator for Grid Environment

    OpenAIRE

    Prajapati, Harshad B.; Shah, Vipul A.

    2012-01-01

    In the last decade, scheduling of Directed Acyclic Graph (DAG) application in the context of Grid environment has attracted attention of many researchers. However, deployment of Grid environment requires skills, efforts, budget, and time. Although various simulation toolkits or frameworks are available for simulating Grid environment, either they support different possible studies in Grid computing area or takes lot of efforts in molding them to make them suitable for scheduling of DAG applic...

  7. Advances in the Simulation-Based Analysis of Attitude Change

    OpenAIRE

    Voinea, Camelia Florela

    2012-01-01

    In this paper we provide an overview of the most relevant research work on the simulation of attitudes which evolved in the late 90’s and mainly after the year 2000. The general framework for the modeling, simulation and computational research on attitudes integrates research approaches (both fundamental and applicative) which combine theories from sociology, social psychology, social economics, political science, conflict theories, human-computer interaction areas with complexity theory, com...

  8. On the simulation and analytical modeling of on-state DC characteristics of Silicon Carbide Double-implanted MOSFETs

    Science.gov (United States)

    Jaikumar, M. G.; Rao, R. Ramakrishna; Karmalkar, Shreepad

    2015-12-01

    The high concentration of interface traps in SiC Double-implanted (D) MOSFETs makes the threshold voltage imprecise, and kills the surface mobility which raises the channel and accumulation layer resistances. Using a detailed comparison with numerical simulations, we examine the extent to which the above factors make analytical on-resistance models, which have proved useful for designing Si DMOSFETs, inaccurate for SiC DMOSFET design. Practical devices are 3-D; however, 3-D simulation is time and resource intensive, and prone to convergence problems. We discuss prediction of 3-D simulations of a square cell SiC DMOSFET having interface traps, field dependent mobility and non-uniform doping, using either 2-D simulation of a linear cell device and "inaccurate" analytical models, or 2-D simulation using rotational symmetry. Finally, we report a procedure for calibration of the mobility and interface trap parameters useful for simulating the on-state DC behavior of 4H-SiC DMOSFETs including the effect of elevated temperatures.

  9. Advanced visualization technology for terascale particle accelerator simulations

    OpenAIRE

    Ma, K-L; Schussman, G.; Wilson, B.; Ko, K.; Qiang, J.; Ryne, R.

    2002-01-01

    This paper presents two new hardware-assisted rendering techniques developed for interactive visualization of the terascale data generated from numerical modeling of nextgeneration accelerator designs. The first technique, based on a hybrid rendering approach, makes possible interactive exploration of large-scale particle data from particle beam dynamics modeling. The second technique, based on a compact texture-enhanced representation, exploits the advanced features of commodity graphic...

  10. Numerical Simulations and Optimisation in Forming of Advanced Materials

    Science.gov (United States)

    Huétink, J.

    2007-04-01

    With the introduction of new materials as high strength steels, metastable steels and fiber reinforce composites, the need for advanced physically valid constitutive models arises. A biaxial test equipment is developed and applied for the determination of material data as well as for validation of material models. An adaptive through- thickness integration scheme for plate elements is developed, which improves the accuracy of spring back prediction at minimal costs. An optimization strategy is proposed that assists an engineer to model an optimization problem.

  11. Advancements on the simulation of the micro injection moulding process

    DEFF Research Database (Denmark)

    Marhöfer, David Maximilian; Tosello, Guido; Hansen, Hans Nørgaard;

    2013-01-01

    Process simulations are applied in micro injection molding with the same purpose as in conventional injection molding: aiming at optimization and support of the design of mold, inserts, plastic products, and the process itself. Available software packages are however not well suited for micro...... injection molding, because they are developed for macro plastic parts and they are therefore limited in the capability of modeling the polymer flow in micro cavities properly. However, new opportunities for improved accuracy have opened up due to current developments of the simulation technology. Hence, new...... strategies and aspects for comprehensive simulation models which provide more precise results for micro injection molding are discussed. Modeling and meshing recommendations are presented, leading to a multi-scale mesh of all relevant units in the injection molding process. The implementation of the process...

  12. Finite analytic method based on mixed-form Richards' equation for simulating water flow in vadose zone

    Science.gov (United States)

    Zhang, Zaiyong; Wang, Wenke; Yeh, Tian-chyi Jim; Chen, Li; Wang, Zhoufeng; Duan, Lei; An, Kedong; Gong, Chengcheng

    2016-06-01

    In this paper, we develop a finite analytic method (FAMM), which combines flexibility of numerical methods and advantages of analytical solutions, to solve the mixed-form Richards' equation. This new approach minimizes mass balance errors and truncation errors associated with most numerical approaches. We use numerical experiments to demonstrate that FAMM can obtain more accurate numerical solutions and control the global mass balance better than modified Picard finite difference method (MPFD) as compared with analytical solutions. In addition, FAMM is superior to the finite analytic method based on head-based Richards' equation (FAMH). Besides, FAMM solutions are compared to analytical solutions for wetting and drying processes in Brindabella Silty Clay Loam and Yolo Light Clay soils. Finally, we demonstrate that FAMM yields comparable results with those from MPFD and Hydrus-1D for simulating infiltration into other different soils under wet and dry conditions. These numerical experiments further confirm the fact that as long as a hydraulic constitutive model captures general behaviors of other models, it can be used to yield flow fields comparable to those based on other models.

  13. Numerical hydrodynamic simulations based on semi-analytic galaxy merger trees: method and Milky Way-like galaxies

    Science.gov (United States)

    Moster, Benjamin P.; Macciò, Andrea V.; Somerville, Rachel S.

    2014-01-01

    We present a new approach to study galaxy evolution in a cosmological context. We combine cosmological merger trees and semi-analytic models of galaxy formation to provide the initial conditions for multimerger hydrodynamic simulations. In this way, we exploit the advantages of merger simulations (high resolution and inclusion of the gas physics) and semi-analytic models (cosmological background and low computational cost), and integrate them to create a novel tool. This approach allows us to study the evolution of various galaxy properties, including the treatment of the hot gaseous halo from which gas cools and accretes on to the central disc, which has been neglected in many previous studies. This method shows several advantages over other methods. As only the particles in the regions of interest are included, the run time is much shorter than in traditional cosmological simulations, leading to greater computational efficiency. Using cosmological simulations, we show that multiple mergers are expected to be more common than sequences of isolated mergers, and therefore studies of galaxy mergers should take this into account. In this pilot study, we present our method and illustrate the results of simulating 10 Milky Way-like galaxies since z = 1. We find good agreement with observations for the total stellar masses, star formation rates, cold gas fractions and disc scalelength parameters. We expect that this novel numerical approach will be very useful for pursuing a number of questions pertaining to the transformation of galaxy internal structure through cosmic time.

  14. Advancing Simulation Reusability - Report on NATO MSG-042 Findings

    NARCIS (Netherlands)

    Reif, B.M.; Wharton, W.D.; Gonzalez-Godoy, S.; McGlynn, L.; San Jose, A.; Elliot, R.; Franzen, S.; Lecinq, X.; Huiskamp, W.; Edmondson, D.

    2006-01-01

    In many cases, the training and decision support needs of military users are urgent; operations can not wait and missions have to be accomplished. Simulators, wargames scenarios and experiments should be ready 'yesterday'. New kinds of operations, environments, tactics, equipment and force configura

  15. Advancing Simulation Reusability - Report on NATO MSG-042 Findings

    NARCIS (Netherlands)

    Reif, B.M.; Wharton, W.D.; Gonzalez-Godoy, S.; McGlynn, L.; San Jose, A.; Elliot, R.; Franzen, S.; Lecenq, X.; Huiskamp, W.; Edmondson, D.

    2007-01-01

    In many cases, the training and decision support needs of military users are urgent; operations cannot wait and missions have to be accomplished. Simulators, wargames scenarios and experiments should be ready 'yesterday'. New kinds of operations, environments, tactics, equipment and force configurat

  16. Recent Advances in Underwater Acoustic Modelling and Simulation

    Science.gov (United States)

    ETTER, P. C.

    2001-02-01

    A comprehensive review of international developments in underwater acoustic modelling is used to construct an updated technology baseline containing 107 propagation models, 16 noise models, 17 reverberation models and 25 sonar performance models. This updated technology baseline represents a 30% increase over a previous baseline published in 1996. When executed in higher-level simulations, these models can generate predictive and diagnostic outputs that are useful to acoustical oceanographers or sonar technologists in the analysis of complex systems operating in the undersea environment. Recent modelling developments described in the technical literature suggest two principal areas of application: low-frequency, inverse acoustics in deep water; and high-frequency, bottom-interacting acoustics in coastal regions. Rapid changes in global geopolitics have opened new avenues for collaboration, thereby facilitating the transfer of modelling and simulation technologies among members of the international community. This accelerated technology transfer has created new imperatives for international standards in modelling and simulation architectures. National and international activities to promote interoperability among modelling and simulation efforts in government, industry and academia are reviewed and discussed.

  17. Advanced Simulation and Computing Co-Design Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Ang, James A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hoang, Thuc T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kelly, Suzanne M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); McPherson, Allen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Neely, Rob [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-11-01

    This ASC Co-design Strategy lays out the full continuum and components of the co-design process, based on what we have experienced thus far and what we wish to do more in the future to meet the program’s mission of providing high performance computing (HPC) and simulation capabilities for NNSA to carry out its stockpile stewardship responsibility.

  18. Simulation for Supporting Scale-Up of a Fluidized Bed Reactor for Advanced Water Oxidation

    OpenAIRE

    Farhana Tisa; Abdul Aziz Abdul Raman; Wan Mohd Ashri Wan Daud

    2014-01-01

    Simulation of fluidized bed reactor (FBR) was accomplished for treating wastewater using Fenton reaction, which is an advanced oxidation process (AOP). The simulation was performed to determine characteristics of FBR performance, concentration profile of the contaminants, and various prominent hydrodynamic properties (e.g., Reynolds number, velocity, and pressure) in the reactor. Simulation was implemented for 2.8 L working volume using hydrodynamic correlations, continuous equation, and simp...

  19. Advances in large-eddy simulation of a wind turbine wake

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, A; Crespo, A; Migoya, E; Garcia, J [Departamento de IngenierIa Energetica y Fluidomecanica, ETSII, Universidad iPolitecnica de Madrid. C/Jose Gutierrez Abascal, 2, CP., 28006, Madrid (Spain)

    2007-07-15

    A CFD code has been developed based on a Large-Eddy Simulation (LES) approach. The turbine is simulated by concentrated drag forces, and is placed in an environment with turbulence anisotropy properties similar to the ones of the real atmosphere. Comparisons with experimental data and with analytical correlations have been performed, and the results are found to be in good agreement with both, suggesting that LES is a potentially useful tool in the investigation of detailed wake flow.

  20. Interim Service ISDN Satellite (ISIS) simulator development for advanced satellite designs and experiments

    Science.gov (United States)

    Pepin, Gerard R.

    1992-01-01

    The simulation development associated with the network models of both the Interim Service Integrated Services Digital Network (ISDN) Satellite (ISIS) and the Full Service ISDN Satellite (FSIS) architectures is documented. The ISIS Network Model design represents satellite systems like the Advanced Communications Technology Satellite (ACTS) orbiting switch. The FSIS architecture, the ultimate aim of this element of the Satellite Communications Applications Research (SCAR) Program, moves all control and switching functions on-board the next generation ISDN communications satellite. The technical and operational parameters for the advanced ISDN communications satellite design will be obtained from the simulation of ISIS and FSIS engineering software models for their major subsystems. Discrete event simulation experiments will be performed with these models using various traffic scenarios, design parameters, and operational procedures. The data from these simulations will be used to determine the engineering parameters for the advanced ISDN communications satellite.

  1. Nuclear energy advance modeling and simulation program-Fuels integrated performance and safety code program - A multi-scale approach to modeling and simulations

    International Nuclear Information System (INIS)

    development. NEAMS is a natural extension of the TFC M and S program with a consideration of a larger scope. Therefore, the most of TFC M and S roadmap goals and requirements remained same in this program plan. The M and S approach is predicated upon transferring the recent advances in computational sciences and computer technologies into the fuel development enterprise. The NEAMS fuels IPSC project will couple computational science with recent advances in fundamental understanding of physical phenomena through ab initio modeling and targeted experimentation to leapfrog, many fuel-development activities. Realizing the full benefits of this approach will likely take some time. However, it is important that the developmental activities for modeling and simulation are tightly coupled with the activities of the AFCI campaigns to maximize feedback effects and accelerate both the experimental and analytical elements of the programs towards a common objective. The close integration of modeling and simulation, and experimental activities and the verification, validation, uncertainty quantification and licensing program, also enables science-based predictions subjected to rigorous verification and validation and explicit quantification of uncertainties embedded within these predictions. The primary objective of the NEAMS fuels IPSC project is to deliver a coupled, three dimensional, predictive computational tool for nuclear fuel pins and assemblies, applicable to both existing and future reactor fuel design, fabrication and for both normal and abnormal operating conditions. The validated tools can be used for lifetime extension, development of more informed safety margins, and the design of future fuels for potential new nuclear systems. It is important to re-emphasize that the NEAM fuels IPSCs objective of a successful modeling and simulation program is not a luxury but an indispensable necessity for the future of the nuclear energy. Without NEAMS fuels IPSC capabilities the use of

  2. Use of simulators for validation of advanced plant monitoring systems

    International Nuclear Information System (INIS)

    This paper describes how the full-scope nuclear power plant simulator of Doel (Belgium) was used to assess Situation Awareness for the validation of a process monitoring and supervision system, named DIMOS. The method (derived from a method originally developed for the aerospace industry) has been adapted and applied to compare the efficiency of two versions of the monitoring system: Alarm-masking and non alarm-masking versions of DIMOS have been analysed in their ability to support Situation Awareness, to improve performance and to fulfil the satisfaction of operators. Both normal power plant operating conditions and abnormal operating conditions were simulated and a large number of power plant operators were involved in the evaluation. The paper focuses on the rationale behind the 'Situation Awareness' evaluation, the experiment environment and the results regarding the added value of the alarm masking version of the monitoring system. (author)

  3. New Analytical Methods for the Surface/Interface and the Micro-Structures in Advanced Nanocomposite Materials by Synchrotron Radiation

    International Nuclear Information System (INIS)

    Analytical methods of surface/interface structure and micro-structure in advanced nanocomposite materials by using the synchrotron radiation are introduced. Recent results obtained by the energy-tunable and highly collimated brilliant X-rays, in-situ wide angle/small angle X-ray diffraction with high accuracy are reviewed. It is shown that small angle X-ray scattering is one of the best methods to characterize nanoparticle dispersibility, filler aggregate/agglomerate structures and in-situ observation of hierarchical structure deformation in filled rubber under cyclic stretch. Grazing Incidence(small and wide angle) X-ray Scattering are powerful to analyze the sintering process of metal nanoparticle by in-situ observation as well as the orientation of polymer molecules and crystalline orientation at very thin surface layer (ca 7nm) of polymer film. While the interaction and conformation of adsorbed molecule at interface can be investigated by using high energy X-ray XPS with Enough deep position (ca 9 micron m). (author)

  4. New Analytical Methods for the Surface/ Interface and the Micro-Structures in Advanced Nanocomposite Materials by Synchrotron Radiation

    Directory of Open Access Journals (Sweden)

    K. Nakamae

    2010-12-01

    Full Text Available Analytical methods of surface/interface structure and micro-structure in advanced nanocomposite materials by using the synchrotron radiation are introduced. Recent results obtained by the energy-tunable and highly collimated brilliant X-rays, in-situ wide angle/small angle X-ray diffraction with high accuracy are reviewed. It is shown that small angle X-ray scattering is one of the best methods to characterize nanoparticle dispersibility, filler aggregate/agglomerate structures and in-situ observation of hierarchical structure deformation in filled rubber under cyclic stretch. Grazing Incidence(small and wide angle X-ray Scattering are powerful to analyze the sintering process of metal nanoparticle by in-situ observation as well as the orientation of polymer molecules and crystalline orientation at very thin surface layer (ca 7nm of polymer film. While the interaction and conformation of adsorbed molecule at interface can be investigated by using high energy X-ray XPS with Enough deep position (ca 9 micron m.

  5. Use of advanced simulations in fuel performance codes

    International Nuclear Information System (INIS)

    The simulation of the cylindrical fuel rod behaviour in a reactor or a storage pool for spent fuel requires a fuel performance code. Such tool solves the equations for the heat transfer, the stresses and strains in fuel and cladding, the evolution of several isotopes and the behaviour of various fission products in the fuel rod. The main equations along with their limitations are briefly described. The current approaches adopted for overcoming these limitations and the perspectives are also outlined. (author)

  6. Advanced vectorial simulation of VCSELs with nano structures invited paper

    DEFF Research Database (Denmark)

    Chung, Il-Sug; Mørk, Jesper

    2009-01-01

    The single-mode properties and design issues of three vertical-cavity surface-emitting laser (VCSEL) structures incorporating nano structures are rigorously investigated. Nano structuring enables to deliver selective pumping or loss to the fundamental mode as well as stabilizing the output...... polarization state. Comparison of three vectorial simulation methods reveals that the modal expansion method is suitable for treating the nano structured VCSEL designs....

  7. Advanced Dynamically Adaptive Algorithms for Stochastic Simulations on Extreme Scales

    Energy Technology Data Exchange (ETDEWEB)

    Xiu, Dongbin [Purdue Univ., West Lafayette, IN (United States)

    2016-06-21

    The focus of the project is the development of mathematical methods and high-performance com- putational tools for stochastic simulations, with a particular emphasis on computations on extreme scales. The core of the project revolves around the design of highly e cient and scalable numer- ical algorithms that can adaptively and accurately, in high dimensional spaces, resolve stochastic problems with limited smoothness, even containing discontinuities.

  8. Simulation of an advanced techniques of ion propulsion Rocket system

    Science.gov (United States)

    Bakkiyaraj, R.

    2016-07-01

    The ion propulsion rocket system is expected to become popular with the development of Deuterium,Argon gas and Hexagonal shape Magneto hydrodynamic(MHD) techniques because of the stimulation indirectly generated the power from ionization chamber,design of thrust range is 1.2 N with 40 KW of electric power and high efficiency.The proposed work is the study of MHD power generation through ionization level of Deuterium gas and combination of two gaseous ions(Deuterium gas ions + Argon gas ions) at acceleration stage.IPR consists of three parts 1.Hexagonal shape MHD based power generator through ionization chamber 2.ion accelerator 3.Exhaust of Nozzle.Initially the required energy around 1312 KJ/mol is carrying out the purpose of deuterium gas which is changed to ionization level.The ionized Deuterium gas comes out from RF ionization chamber to nozzle through MHD generator with enhanced velocity then after voltage is generated across the two pairs of electrode in MHD.it will produce thrust value with the help of mixing of Deuterium ion and Argon ion at acceleration position.The simulation of the IPR system has been carried out by MATLAB.By comparing the simulation results with the theoretical and previous results,if reaches that the proposed method is achieved of thrust value with 40KW power for simulating the IPR system.

  9. Wave-like warp propagation in circumbinary discs I. Analytic theory and numerical simulations

    OpenAIRE

    Facchini, Stefano; Lodato, Giuseppe; Price, Daniel J.

    2013-01-01

    In this paper we analyse the propagation of warps in protostellar circumbinary discs. We use these systems as a test environment in which to study warp propagation in the bending-wave regime, with the addition of an external torque due to the binary gravitational potential. In particular, we want to test the linear regime, for which an analytic theory has been developed. In order to do so, we first compute analytically the steady state shape of an inviscid disc subject to the binary torques. ...

  10. Advanced visualization technology for terascale particle accelerator simulations

    International Nuclear Information System (INIS)

    This paper presents two new hardware-assisted rendering techniques developed for interactive visualization of the terascale data generated from numerical modeling of next generation accelerator designs. The first technique, based on a hybrid rendering approach, makes possible interactive exploration of large-scale particle data from particle beam dynamics modeling. The second technique, based on a compact texture-enhanced representation, exploits the advanced features of commodity graphics cards to achieve perceptually effective visualization of the very dense and complex electromagnetic fields produced from the modeling of reflection and transmission properties of open structures in an accelerator design. Because of the collaborative nature of the overall accelerator modeling project, the visualization technology developed is for both desktop and remote visualization settings. We have tested the techniques using both time varying particle data sets containing up to one billion particle s per time step and electromagnetic field data sets with millions of mesh elements

  11. An advanced leakage scheme for neutrino treatment in astrophysical simulations

    CERN Document Server

    Perego, Albino; Käppeli, Roger

    2015-01-01

    We present an Advanced Spectral Leakage (ASL) scheme to model neutrinos in the context of core-collapse supernovae and compact binary mergers. Based on previous gray leakage schemes, the ASL scheme computes the neutrino cooling rates by interpolating local production and diffusion rates (relevant in optically thin and thick regimes, respectively), separately for discretized values of the neutrino energy. Neutrino trapped components are also modeled, based on equilibrium and timescale arguments. The better accuracy achieved by the spectral treatment allows a more reliable computation of neutrino heating rates in optically thin conditions. The scheme has been calibrated and tested against Boltzmann transport in the context of Newtonian spherically symmetric models of core-collapse supernovae. ASL shows a very good qualitative and a partial quantitative agreement, for key quantities from collapse to a few hundreds of milliseconds after core bounce. We have proved the adaptability and flexibility of our ASL schem...

  12. Computational modeling, optimization and manufacturing simulation of advanced engineering materials

    CERN Document Server

    2016-01-01

    This volume presents recent research work focused in the development of adequate theoretical and numerical formulations to describe the behavior of advanced engineering materials.  Particular emphasis is devoted to applications in the fields of biological tissues, phase changing and porous materials, polymers and to micro/nano scale modeling. Sensitivity analysis, gradient and non-gradient based optimization procedures are involved in many of the chapters, aiming at the solution of constitutive inverse problems and parameter identification. All these relevant topics are exposed by experienced international and inter institutional research teams resulting in a high level compilation. The book is a valuable research reference for scientists, senior undergraduate and graduate students, as well as for engineers acting in the area of computational material modeling.

  13. Semi-physiologic model validation and bioequivalence trials simulation to select the best analyte for acetylsalicylic acid.

    Science.gov (United States)

    Cuesta-Gragera, Ana; Navarro-Fontestad, Carmen; Mangas-Sanjuan, Victor; González-Álvarez, Isabel; García-Arieta, Alfredo; Trocóniz, Iñaki F; Casabó, Vicente G; Bermejo, Marival

    2015-07-10

    The objective of this paper is to apply a previously developed semi-physiologic pharmacokinetic model implemented in NONMEM to simulate bioequivalence trials (BE) of acetyl salicylic acid (ASA) in order to validate the model performance against ASA human experimental data. ASA is a drug with first-pass hepatic and intestinal metabolism following Michaelis-Menten kinetics that leads to the formation of two main metabolites in two generations (first and second generation metabolites). The first aim was to adapt the semi-physiological model for ASA in NOMMEN using ASA pharmacokinetic parameters from literature, showing its sequential metabolism. The second aim was to validate this model by comparing the results obtained in NONMEM simulations with published experimental data at a dose of 1000 mg. The validated model was used to simulate bioequivalence trials at 3 dose schemes (100, 1000 and 3000 mg) and with 6 test formulations with decreasing in vivo dissolution rate constants versus the reference formulation (kD 8-0.25 h (-1)). Finally, the third aim was to determine which analyte (parent drug, first generation or second generation metabolite) was more sensitive to changes in formulation performance. The validation results showed that the concentration-time curves obtained with the simulations reproduced closely the published experimental data, confirming model performance. The parent drug (ASA) was the analyte that showed to be more sensitive to the decrease in pharmaceutical quality, with the highest decrease in Cmax and AUC ratio between test and reference formulations. PMID:25869458

  14. Advanced Simulation Technology to Design Etching Process on CMOS Devices

    Science.gov (United States)

    Kuboi, Nobuyuki

    2015-09-01

    Prediction and control of plasma-induced damage is needed to mass-produce high performance CMOS devices. In particular, side-wall (SW) etching with low damage is a key process for the next generation of MOSFETs and FinFETs. To predict and control the damage, we have developed a SiN etching simulation technique for CHxFy/Ar/O2 plasma processes using a three-dimensional (3D) voxel model. This model includes new concepts for the gas transportation in the pattern, detailed surface reactions on the SiN reactive layer divided into several thin slabs and C-F polymer layer dependent on the H/N ratio, and use of ``smart voxels''. We successfully predicted the etching properties such as the etch rate, polymer layer thickness, and selectivity for Si, SiO2, and SiN films along with process variations and demonstrated the 3D damage distribution time-dependently during SW etching on MOSFETs and FinFETs. We confirmed that a large amount of Si damage was caused in the source/drain region with the passage of time in spite of the existing SiO2 layer of 15 nm in the over etch step and the Si fin having been directly damaged by a large amount of high energy H during the removal step of the parasitic fin spacer leading to Si fin damage to a depth of 14 to 18 nm. By analyzing the results of these simulations and our previous simulations, we found that it is important to carefully control the dose of high energy H, incident energy of H, polymer layer thickness, and over-etch time considering the effects of the pattern structure, chamber-wall condition, and wafer open area ratio. In collaboration with Masanaga Fukasawa and Tetsuya Tatsumi, Sony Corporation. We thank Mr. T. Shigetoshi and Mr. T. Kinoshita of Sony Corporation for their assistance with the experiments.

  15. Electric and plug-in hybrid vehicles advanced simulation methodologies

    CERN Document Server

    Varga, Bogdan Ovidiu; Moldovanu, Dan; Iclodean, Calin

    2015-01-01

    This book is designed as an interdisciplinary platform for specialists working in electric and plug-in hybrid electric vehicles powertrain design and development, and for scientists who want to get access to information related to electric and hybrid vehicle energy management, efficiency and control. The book presents the methodology of simulation that allows the specialist to evaluate electric and hybrid vehicle powertrain energy flow, efficiency, range and consumption. The mathematics behind each electric and hybrid vehicle component is explained and for each specific vehicle the powertrain

  16. Silicon and beyond advanced device models and circuit simulators

    CERN Document Server

    Shur, Michael S

    2000-01-01

    The steady downscaling of device-feature size combined with a rapid increase in circuit complexity as well as the introduction of new device concepts based on non-silicon-material systems poses great challenges for device and circuit designers. One of the major tasks is the development of new and improved device models needed for accurate device and circuit design. Another task is the development of new circuit-simulation tools to handle very large and complex circuits. This book addresses both these issues with up-to-date reviews written by leading experts in the field.The first three chapter

  17. Microwave Processing of Simulated Advanced Nuclear Fuel Pellets

    International Nuclear Information System (INIS)

    Throughout the three-year project funded by the Department of Energy (DOE) and lead by Virginia Tech (VT), project tasks were modified by consensus to fit the changing needs of the DOE with respect to developing new inert matrix fuel processing techniques. The focus throughout the project was on the use of microwave energy to sinter fully stabilized zirconia pellets using microwave energy and to evaluate the effectiveness of techniques that were developed. Additionally, the research team was to propose fundamental concepts as to processing radioactive fuels based on the effectiveness of the microwave process in sintering the simulated matrix material.

  18. Recent Advances in the Numerical Simulations of Binary Black Holes

    CERN Document Server

    Marronetti, Pedro

    2011-01-01

    Since the breakthrough papers from 2005/2006, the field of numerical relativity has experienced a growth spurt that took the two-body problem in general relativity from the category of "really-hard-problems" to the realm of "things-we-know-how-to-do". Simulations of binary black holes in circular orbits, the holy grail of numerical relativity, are now tractable problems that lead to some of the most spectacular results in general relativity in recent years. We cover here some of the latest achievements and highlight the field's next challenges.

  19. Analytical Modeling and Simulation of Four-Switch Hybrid Power Filter Working with Sixfold Switching Symmetry

    Czech Academy of Sciences Publication Activity Database

    Tlustý, J.; Škramlík, Jiří; Švec, J.; Valouch, Viktor

    2012-01-01

    Roč. 2012, č. 292178 (2012), s. 1-17. ISSN 1024-123X Institutional support: RVO:61388998 Keywords : analytical modeling * four-switch hybrid power filter * sixfold switching symmetry Subject RIV: JA - Electronic s ; Optoelectronics, Electrical Engineering Impact factor: 1.383, year: 2012 http://www.hindawi.com/journals/mpe/2012/292178/

  20. Advances in comprehensive gyrokinetic simulations of transport in tokamaks

    International Nuclear Information System (INIS)

    A continuum global gyrokinetic code GYRO has been developed to comprehensively simulate core turbulent transport in actual experimental profiles and enable direct quantitative comparisons to the experimental transport flows. GYRO not only treats the now standard ion temperature gradient (ITG) mode turbulence, but also treats trapped and passing electrons with collisions and finite β, equilibrium ExB shear stabilization, and all in real tokamak geometry. Most importantly the code operates at finite relative gyroradius (ρ*) so as to treat the profile shear stabilization and nonlocal effects which can break gyroBohm scaling. The code operates in either a cyclic flux-tube limit (which allows only gyroBohm scaling) or globally with physical profile variation. Bohm scaling of DIII-D L-mode has been simulated with power flows matching experiment within error bars on the ion temperature gradient. Mechanisms for broken gyroBohm scaling, neoclassical ion flows embedded in turbulence, turbulent dynamos and profile corrugations, are illustrated. (author)

  1. Simulation models and designs for advanced Fischer-Tropsch technology

    Energy Technology Data Exchange (ETDEWEB)

    Choi, G.N.; Kramer, S.J.; Tam, S.S. [Bechtel Corp., San Francisco, CA (United States)

    1995-12-31

    Process designs and economics were developed for three grass-roots indirect Fischer-Tropsch coal liquefaction facilities. A baseline and an alternate upgrading design were developed for a mine-mouth plant located in southern Illinois using Illinois No. 6 coal, and one for a mine-mouth plane located in Wyoming using Power River Basin coal. The alternate design used close-coupled ZSM-5 reactors to upgrade the vapor stream leaving the Fischer-Tropsch reactor. ASPEN process simulation models were developed for all three designs. These results have been reported previously. In this study, the ASPEN process simulation model was enhanced to improve the vapor/liquid equilibrium calculations for the products leaving the slurry bed Fischer-Tropsch reactors. This significantly improved the predictions for the alternate ZSM-5 upgrading design. Another model was developed for the Wyoming coal case using ZSM-5 upgrading of the Fischer-Tropsch reactor vapors. To date, this is the best indirect coal liquefaction case. Sensitivity studies showed that additional cost reductions are possible.

  2. An analytical solution for simulation of the fission gas behaviors with time-dependent piece-wise boundary resolution

    Energy Technology Data Exchange (ETDEWEB)

    Cui Yi; Huo Yongzhong [Department of Mechanics and Engineering Science, Fudan University, Shanghai 200433 (China); Ding Shurong, E-mail: dsr1971@163.com [Department of Mechanics and Engineering Science, Fudan University, Shanghai 200433 (China) and Science and Technology on Reactor System Design Technology Laboratory, Nuclear Power Institution of China, Chengdu 610041, Sichuan (China); Zhang Lin; Li Yuanming [Science and Technology on Reactor System Design Technology Laboratory, Nuclear Power Institution of China, Chengdu 610041, Sichuan (China)

    2012-05-15

    An analytical solution of gas concentration for the equivalent spherical grain is obtained first in Laplace space, then the inverse-Laplace transformed solution is further developed. The corresponding analytical expressions for the grain boundary gaseous swelling and the fission gas release in UO{sub 2} nuclear fuels are developed in the absence of grain growth. The following phenomena and assumptions are taken into account in our model, including the gas atom diffusion, saturation and the time-varying piece-wise inter-granular resolution. The explicit expression for saturation time of the grain boundary gas atoms is also obtained. Our approximated analytical solutions for the fission gas behaviors are validated through comparison with those solved by finite difference method. Good agreement has been achieved for the cases with different input parameters. Based on the developed analytical solutions, the effects of the grain sizes and the external pressure on the fission gas behaviors are investigated. This study lays a foundation for the multi-scale simulation of the thermo-mechanical behaviors in nuclear fuel elements.

  3. An analytical solution for simulation of the fission gas behaviors with time-dependent piece-wise boundary resolution

    International Nuclear Information System (INIS)

    An analytical solution of gas concentration for the equivalent spherical grain is obtained first in Laplace space, then the inverse-Laplace transformed solution is further developed. The corresponding analytical expressions for the grain boundary gaseous swelling and the fission gas release in UO2 nuclear fuels are developed in the absence of grain growth. The following phenomena and assumptions are taken into account in our model, including the gas atom diffusion, saturation and the time-varying piece-wise inter-granular resolution. The explicit expression for saturation time of the grain boundary gas atoms is also obtained. Our approximated analytical solutions for the fission gas behaviors are validated through comparison with those solved by finite difference method. Good agreement has been achieved for the cases with different input parameters. Based on the developed analytical solutions, the effects of the grain sizes and the external pressure on the fission gas behaviors are investigated. This study lays a foundation for the multi-scale simulation of the thermo-mechanical behaviors in nuclear fuel elements.

  4. NATO Advanced Study Institute on Advances in the Computer Simulations of Liquid Crystals

    CERN Document Server

    Zannoni, Claudio

    2000-01-01

    Computer simulations provide an essential set of tools for understanding the macroscopic properties of liquid crystals and of their phase transitions in terms of molecular models. While simulations of liquid crystals are based on the same general Monte Carlo and molecular dynamics techniques as are used for other fluids, they present a number of specific problems and peculiarities connected to the intrinsic properties of these mesophases. The field of computer simulations of anisotropic fluids is interdisciplinary and is evolving very rapidly. The present volume covers a variety of techniques and model systems, from lattices to hard particle and Gay-Berne to atomistic, for thermotropics, lyotropics, and some biologically interesting liquid crystals. Contributions are written by an excellent panel of international lecturers and provides a timely account of the techniques and problems in the field.

  5. Leningrad NPP full scope and analytical simulators as tools for MMI improvement and operator support systems development and testing

    International Nuclear Information System (INIS)

    Training Support Center (TSC) created at the Leningrad NPP (LNPP), Sosnovy Bor, Russia, incorporates full-scope and analytical simulators working in parallel with the prototypes of the expert and interactive systems to provide a new scope of R and D MMI improvement work as for the developer as well as for the user. Possibilities of development, adjusting and testing of any new or up-graded Operators' Support System before its installation at the reference unit's Control Room are described in the paper. These Simulators ensure the modeling of a wide range of accidents and transients and provide with special software and ETHERNET data process communications with the Operators' Support systems' prototypes. The development and adjustment of two state-of-the-art Operators' Support Systems of interest with using of Simulators are described in the paper as an example. These systems have been developed jointly by RRC KI and LNPP team. (author)

  6. Critical Appraisal of Acuros XB and Anisotropic Analytic Algorithm Dose Calculation in Advanced Non-Small-Cell Lung Cancer Treatments

    Energy Technology Data Exchange (ETDEWEB)

    Fogliata, Antonella, E-mail: afc@iosi.ch [Medical Physics Unit, Oncology Institute of Southern Switzerland, Bellinzona (Switzerland); Nicolini, Giorgia; Clivio, Alessandro; Vanetti, Eugenio; Cozzi, Luca [Medical Physics Unit, Oncology Institute of Southern Switzerland, Bellinzona (Switzerland)

    2012-08-01

    Purpose: To assess the clinical impact of the Acuros XB algorithm (implemented in the Varian Eclipse treatment-planning system) in non-small-cell lung cancer (NSCLC) cases. Methods and Materials: A CT dataset of 10 patients presenting with advanced NSCLC was selected and contoured for planning target volume, lungs, heart, and spinal cord. Plans were created for 6-MV and 15-MV beams using three-dimensional conformal therapy, intensity-modulated therapy, and volumetric modulated arc therapy with RapidArc. Calculations were performed with Acuros XB and the Anisotropic Analytical Algorithm. To distinguish between differences coming from the different heterogeneity management and those coming from the algorithm and its implementation, all the plans were recalculated assigning Hounsfield Unit (HU) = 0 (Water) to the CT dataset. Results: Differences in dose distributions between the two algorithms calculated in Water were <0.5%. This suggests that the differences in the real CT dataset can be ascribed mainly to the different heterogeneity management, which is proven to be more accurate in the Acuros XB calculations. The planning target dose difference was stratified between the target in soft tissue, where the mean dose was found to be lower for Acuros XB, with a range of 0.4% {+-} 0.6% (intensity-modulated therapy, 6 MV) to 1.7% {+-} 0.2% (three-dimensional conformal therapy, 6 MV), and the target in lung tissue, where the mean dose was higher for 6 MV (from 0.2% {+-} 0.2% to 1.2% {+-} 0.5%) and lower for 15 MV (from 0.5% {+-} 0.5% to 2.0% {+-} 0.9%). Mean doses to organs at risk presented differences up to 3% of the mean structure dose in the worst case. No particular or systematic differences were found related to the various modalities. Calculation time ratios between calculation time for Acuros XB and the Anisotropic Analytical Algorithm were 7 for three-dimensional conformal therapy, 5 for intensity-modulated therapy, and 0.2 for volumetric modulated arc therapy

  7. Advanced Simulation of Electron Heat Transport in Fusion Plasmas

    International Nuclear Information System (INIS)

    Electron transport in burning plasmas is more important since fusion products first heat electrons. First-principles simulations of electron turbulence are much more challenging due to the multi-scale dynamics of the electron turbulence, and have been made possible by close collaborations between plasma physicists and computational scientists. The GTC simulations of collisionless trapped electron mode (CTEM) turbulence show that the electron heat transport exhibits a gradual transition from Bohm to gyroBohm scaling when the device size is increased. The deviation from the gyroBohm scaling can be induced by large turbulence eddies, turbulence spreading, and non-diffusive transport processes. Analysis of radial correlation function shows that CTEM turbulence eddies are predominantly microscopic but with a significant tail in the mesoscale. A comprehensive analysis of kinetic and fluid time scales shows that zonal flow shearing is the dominant decorrelation mechanism. The mesoscale eddies result from a dynamical process of linear streamers breaking by zonal flows and merging of microscopic eddies. The radial profile of the electron heat conductivity only follows the profile of fluctuation intensity on a global scale, whereas the ion transport tracks more sensitively the local fluctuation intensity. This suggests the existence of a nondiffusive component in the electron heat flux, which arises from the ballistic radial E x B drift of trapped electrons due to a combination of the presence of mesoscale eddies and the weak de-tuning of the toroidal precessional resonance that drives the CTEM instability. On the other hand, the ion radial excursion is not affected by the mesoscale eddies due to a parallel decorrelation, which is not operational for the trapped electrons because of a bounce averaging process associated with the electron fast motion along magnetic field lines. The presence of the nondiffusive component raises question on the applicability of the usual

  8. Advanced simulation of electron heat transport in fusion plasmas

    International Nuclear Information System (INIS)

    Electron transport in burning plasmas is more important since fusion products first heat electrons. First-principles simulations of electron turbulence are much more challenging due to the multi-scale dynamics of the electron turbulence, and have been made possible by close collaborations between plasma physicists and computational scientists. The GTC simulations of collisionless trapped electron mode (CTEM) turbulence show that the electron heat transport exhibits a gradual transition from Bohm to gyroBohm scaling when the device size is increased. The deviation from the gyroBohm scaling can be induced by large turbulence eddies, turbulence spreading, and non-diffusive transport processes. Analysis of radial correlation function shows that CTEM turbulence eddies are predominantly microscopic but with a significant tail in the mesoscale. A comprehensive analysis of kinetic and fluid time scales shows that zonal flow shearing is the dominant decorrelation mechanism. The mesoscale eddies result from a dynamical process of linear streamers breaking by zonal flows and merging of microscopic eddies. The radial profile of the electron heat conductivity only follows the profile of fluctuation intensity on a global scale, whereas the ion transport tracks more sensitively the local fluctuation intensity. This suggests the existence of a nondiffusive component in the electron heat flux, which arises from the ballistic radial E X B drift of trapped electrons due to a combination of the presence of mesoscale eddies and the weak de-tuning of the toroidal precessional resonance that drives the CTEM instability. On the other hand, the ion radial excursion is not affected by the mesoscale eddies due to a parallel decorrelation, which is not operational for the trapped electrons because of a bounce averaging process associated with the electron fast motion along magnetic field lines. The presence of the nondiffusive component raises question on the applicability of the usual

  9. Advanced simulation of damage of reinforced concrete structures under impact

    International Nuclear Information System (INIS)

    The efficiency of the discrete element method for studying the fracture of heterogeneous media has been demonstrated, but it is limited by the size of the computational model. A coupling between the discrete element and the finite element methods is proposed to handle the simulation of impacts on large structures. The structure is split into sub-domains in each of which the method of analysis is adapted to optimise the modelling of the structure behaviour under impact. The DEM takes naturally into account the discontinuities and is used to model the media in the impact zone. The remaining structure is modelled by the FEM. Proposed combined DE/FE algorithm is implemented in the Europlexus fast dynamics software and parallelized with MPI formalism. The efficiency of the Europlexus multi-domain MPI parallel version is tested. (authors)

  10. Advanced wellbore thermal simulator GEOTEMP2 user manual

    Energy Technology Data Exchange (ETDEWEB)

    Mondy, L.A.; Duda, L.E.

    1984-11-01

    GEOTEMP2 is a wellbore thermal simulator computer code designed for geothermal drilling and production applications. The code treats natural and forced convection and conduction within the wellbore and heat conduction within the surrounding rock matrix. A variety of well operations can be modeled including injection, production, forward, and reverse circulation with gas or liquid, gas or liquid drilling, and two-phase steam injection and production. Well completion with several different casing sizes and cement intervals can be modeled. The code allows variables suchas flow rate to change with time enabling a realistic treatment of well operations. This user manual describes the input required to properly operate the code. Ten sample problems are included which illustrate all the code options. Complete listings of the code and the output of each sample problem are provided.

  11. Using CONFIG for Simulation of Operation of Water Recovery Subsystems for Advanced Control Software Evaluation

    Science.gov (United States)

    Malin, Jane T.; Flores, Luis; Fleming, Land; Throop, Daiv

    2002-01-01

    A hybrid discrete/continuous simulation tool, CONFIG, has been developed to support evaluation of the operability life support systems. CON FIG simulates operations scenarios in which flows and pressures change continuously while system reconfigurations occur as discrete events. In simulations, intelligent control software can interact dynamically with hardware system models. CONFIG simulations have been used to evaluate control software and intelligent agents for automating life support systems operations. A CON FIG model of an advanced biological water recovery system has been developed to interact with intelligent control software that is being used in a water system test at NASA Johnson Space Center

  12. The role of advanced calculation and simulation tools in the evolution of fuel

    International Nuclear Information System (INIS)

    This article is focused on the role of the advanced calculation/simulation tools on the development of the fuel designs as well as in the assessment of the effect of the changes in the operation. With this purpose, the article describes and shows some examples of the use by ENUSA of some of these tools in the fuel engineering. To conclude, the future on the evolution of the advanced tools is also presented. (Author)

  13. Thermal, quantum and simulated quantum annealing: analytical comparisons for simple models

    OpenAIRE

    Bapst, Victor; Semerjian, Guilhem

    2015-01-01

    We study various annealing dynamics, both classical and quantum, for simple mean-field models and explain how to describe their behavior in the thermodynamic limit in terms of differential equations. In particular we emphasize the differences between quantum annealing (i.e. evolution with Schr\\"odinger equation) and simulated quantum annealing (i.e. annealing of a Quantum Monte Carlo simulation).

  14. Design and Test of Advanced Thermal Simulators for an Alkali Metal-Cooled Reactor Simulator

    Science.gov (United States)

    Garber, Anne E.; Dickens, Ricky E.

    2011-01-01

    The Early Flight Fission Test Facility (EFF-TF) at NASA Marshall Space Flight Center (MSFC) has as one of its primary missions the development and testing of fission reactor simulators for space applications. A key component in these simulated reactors is the thermal simulator, designed to closely mimic the form and function of a nuclear fuel pin using electric heating. Continuing effort has been made to design simple, robust, inexpensive thermal simulators that closely match the steady-state and transient performance of a nuclear fuel pin. A series of these simulators have been designed, developed, fabricated and tested individually and in a number of simulated reactor systems at the EFF-TF. The purpose of the thermal simulators developed under the Fission Surface Power (FSP) task is to ensure that non-nuclear testing can be performed at sufficiently high fidelity to allow a cost-effective qualification and acceptance strategy to be used. Prototype thermal simulator design is founded on the baseline Fission Surface Power reactor design. Recent efforts have been focused on the design, fabrication and test of a prototype thermal simulator appropriate for use in the Technology Demonstration Unit (TDU). While designing the thermal simulators described in this paper, effort were made to improve the axial power profile matching of the thermal simulators. Simultaneously, a search was conducted for graphite materials with higher resistivities than had been employed in the past. The combination of these two efforts resulted in the creation of thermal simulators with power capacities of 2300-3300 W per unit. Six of these elements were installed in a simulated core and tested in the alkali metal-cooled Fission Surface Power Primary Test Circuit (FSP-PTC) at a variety of liquid metal flow rates and temperatures. This paper documents the design of the thermal simulators, test program, and test results.

  15. Monte Carlo simulation and analytical calculation of coherent Bremsstrahlung and its polarisation

    Energy Technology Data Exchange (ETDEWEB)

    Natter, F.A.; Grabmayr, P. E-mail: grabmayr@uni-tuebingen.de; Hehl, T.; Owens, R.O.; Wunderlich, S

    2003-12-01

    Spectral distributions for coherent and incoherent Bremsstrahlung produced by electrons on thin diamond radiators are calculated accurately by a Monte Carlo procedure. Realistic descriptions of the electron beam and the physical processes within the radiator have been implemented. Results are compared to measured data. A faster calculation at only a slight loss of precision is possible using analytical expressions which can be derived after simplifying assumptions.

  16. An analytical model for simulating two-dimensional multispecies plume migration

    OpenAIRE

    Chen, Jui-Sheng; Liang, Ching-Ping; Liu, Chen-Wuing; Li, Loretta Y.

    2016-01-01

    The two-dimensional advection-dispersion equations coupled with sequential first-order decay reactions involving arbitrary number of species in groundwater system is considered to predict the two-dimensional plume behavior of decaying contaminant such as radionuclide and dissolved chlorinated solvent. Generalized analytical solutions in compact format are derived through the sequential application of the Laplace, finite Fourier cosine, and generalized integral transform to r...

  17. Crossed source-detector geometry for a novel spray diagnostic: Monte Carlo simulation and analytical results.

    Science.gov (United States)

    Berrocal, Edouard; Churmakov, Dmitry Y; Romanov, Vadim P; Jermy, Mark C; Meglinski, Igor V

    2005-05-01

    Sprays and other industrially relevant turbid media can be quantitatively characterized by light scattering. However, current optical diagnostic techniques generate errors in the intermediate scattering regime where the average number of light scattering is too great for the single scattering to be assumed, but too few for the diffusion approximation to be applied. Within this transitional single-to-multiple scattering regime, we consider a novel crossed source-detector geometry that allows the intensity of single scattering to be measured separately from the higher scattering orders. We verify Monte Carlo calculations that include the imperfections of the experiment against analytical results. We show quantitatively the influence of the detector numerical aperture and the angle between the source and the detector on the relative intensity of the scattering orders in the intermediate single-to-multiple scattering regime. Monte Carlo and analytical calculations of double light-scattering intensity are made with small particles that exhibit isotropic scattering. The agreement between Monte Carlo and analytical techniques validates use of the Monte Carlo approach in the intermediate scattering regime. Monte Carlo calculations are then performed for typical parameters of sprays and aerosols with anisotropic (Mie) scattering in the intermediate single-to-multiple scattering regime. PMID:15881059

  18. State of the Art Assessment of Simulation in Advanced Materials Development

    Science.gov (United States)

    Wise, Kristopher E.

    2008-01-01

    Advances in both the underlying theory and in the practical implementation of molecular modeling techniques have increased their value in the advanced materials development process. The objective is to accelerate the maturation of emerging materials by tightly integrating modeling with the other critical processes: synthesis, processing, and characterization. The aims of this report are to summarize the state of the art of existing modeling tools and to highlight a number of areas in which additional development is required. In an effort to maintain focus and limit length, this survey is restricted to classical simulation techniques including molecular dynamics and Monte Carlo simulations.

  19. No Evidence for Bardeen-Petterson Alignment in GRMHD Simulations and Semi-Analytic Models of Moderately Thin, Prograde, Tilted Accretion Disks

    CERN Document Server

    Zhuravlev, Viacheslav V; Fragile, P Chris; Teixeira, Danilo Morales

    2014-01-01

    In this paper we introduce the first results that use data extracted directly from numerical simulations as inputs to the analytic twisted disk model of Zhuravlev & Ivanov. In both numerical and analytic approaches, fully relativistic models of tilted and twisted disks having a moderate effective viscosity around a slowly rotating Kerr black hole are considered. Qualitatively, the analytic model demonstrates the same dynamics as the simulations, although with some quantitative offset. Namely, the GRMHD simulations generally give smaller variations of tilt and twist across the disk. When the black hole and the disk rotate in the same sense, the simulated tilted disk and analytic model show no sign of Bardeen-Petterson alignment, even in the innermost parts of the disk, where the characteristic time for relaxation to a quasi-stationary configuration is of the same order as the computation time. In the opposite case, when the direction of the disk's rotation is opposite to that of black hole, a partial align...

  20. SU-E-J-145: Validation of An Analytical Model for in Vivo Range Verification Using GATE Monte Carlo Simulation in Proton Therapy

    International Nuclear Information System (INIS)

    Purpose: Predicted PET images on the basis of analytical filtering approach for proton range verification has been successful developed and validated using FLUKA Monte Carlo (MC) codes and phantom measurements. The purpose of the study is to validate the effectiveness of analytical filtering model for proton range verification on GATE/GEANT4 Monte Carlo simulation codes. Methods: In this study, we performed two experiments for validation of predicted β+-isotope by the analytical model with GATE/GEANT4 simulations. The first experiments to evaluate the accuracy of predicting β+-yields as a function of irradiated proton energies. In second experiment, we simulate homogeneous phantoms of different materials irradiated by a mono-energetic pencil-like proton beam. The results of filtered β+-yields distributions by the analytical model is compared with those of MC simulated β+-yields in proximal and distal fall-off ranges. Results: The results investigate the distribution between filtered β+-yields and MC simulated β+-yields distribution in different conditions. First, we found that the analytical filtering can be applied over the whole range of the therapeutic energies. Second, the range difference between filtered β+-yields and MC simulated β+-yields at the distal fall-off region are within 1.5mm for all materials used. The findings validated the usefulness of analytical filtering model on range verification of proton therapy on GATE Monte Carlo simulations. In addition, there is a larger discrepancy between filtered prediction and MC simulated β+-yields using GATE code, especially in proximal region. This discrepancy might Result from the absence of wellestablished theoretical models for predicting the nuclear interactions. Conclusion: Despite the fact that large discrepancies of the distributions between MC-simulated and predicted β+-yields were observed, the study prove the effectiveness of analytical filtering model for proton range verification using

  1. Numerical simulation of production from tight-gas reservoirs by advanced stimulation technologies

    OpenAIRE

    Friedel, Torsten

    2009-01-01

    The present thesis focusses on two main issues: (i) the development of a multi-phase simulation tool for the characteristics of tight-gas reservoirs, and (ii) the investigation of advanced stimulation techniques. The latter mainly implies the analysis of certain damaging mechanisms, as well as the derivation of general modelling guidelines for fractured wells and underbalanced drilling. A special simulation tool is developed, realised in a Fortran-MATLAB coupling. The numerical model is based...

  2. Iron Resources and Oceanic Nutrients: Advancement of Global Environment Simulations

    Science.gov (United States)

    Debaar, H. J.

    2002-12-01

    simulated. An existing plankton ecosystem model already well predicts limitation by four nutrients (N, P, Si, Fe) of two algal groups (diatoms and nanoplankton) including export and CO2 air/sea exchange. This is being expanded with 3 other groups of algae and DMS(P)pathways. Next this extended ecosystem model is being simplified while maintaining reliable output for export and CO2/DMS gas exchange. This unit will then be put into two existing OBCM's. Inputs of Fe from above and below into the oceans have been modeled. Moreover a simple global Fe cycling model has been verified versus field data and insights. Two different OBCM's with same upper ocean ecosystem/DMS unit and Fe cycling will be verified versus pre-industrial and present conditions. Next climate change scenario's, notably changes in Fe inputs, will be run, with special attention to climatic feedbacks (warming) on the oceanic cycles and fluxes.

  3. Advances in multi-physics and high performance computing in support of nuclear reactor power systems modeling and simulation

    International Nuclear Information System (INIS)

    Significant advances in computational performance have occurred over the past two decades, achieved not only by the introduction of more powerful processors but the incorporation of parallelism in computer hardware at all levels. Simultaneous with these hardware and associated system software advances have been advances in modeling physical phenomena and the numerical algorithms to allow their usage in simulation. This paper presents a review of the advances in computer performance, discusses the modeling and simulation capabilities required to address the multi-physics and multi-scale phenomena applicable to a nuclear reactor core simulator, and present examples of relevant physics simulation codes' performances on high performance computers.

  4. Analytic and simulation studies on the use of torque-wheel actuators for the control of flexible robotic arms

    Science.gov (United States)

    Montgomery, Raymond C.; Ghosh, Dave; Kenny, Sean

    1991-01-01

    This paper presents results of analytic and simulation studies to determine the effectiveness of torque-wheel actuators in suppressing the vibrations of two-link telerobotic arms with attached payloads. The simulations use a planar generic model of a two-link arm with a torque wheel at the free end. Parameters of the arm model are selected to be representative of a large space-based robotic arm of the same class as the Space Shuttle Remote Manipulator, whereas parameters of the torque wheel are selected to be similar to those of the Mini-Mast facility at the Langley Research Center. Results show that this class of torque-wheel can produce an oscillation of 2.5 cm peak-to-peak in the end point of the arm and that the wheel produces significantly less overshoot when the arm is issued an abrupt stop command from the telerobotic input station.

  5. The role of experience and advanced training on performance in a motorcycle simulator.

    Science.gov (United States)

    Crundall, David; Stedmon, Alex W; Crundall, Elizabeth; Saikayasit, Rossukorn

    2014-12-01

    Motorcyclists are over-represented in collision statistics. While many collisions may be the direct fault of another road user, a considerable number of fatalities and injuries are due to the actions of the rider. While increased riding experience may improve skills, advanced training courses may be required to evoke the safest riding behaviours. The current research assessed the impact of experience and advanced training on rider behaviour using a motorcycle simulator. Novice riders, experienced riders and riders with advanced training traversed a virtual world through varying speed limits and roadways of different curvature. Speed and lane position were monitored. In a comparison of 60 mph and 40 mph zones, advanced riders rode more slowly in the 40 mph zones, and had greater variation in lane position than the other two groups. In the 60 mph zones, both advanced and experienced riders had greater lane variation than novices. Across the whole ride, novices tended to position themselves closer to the kerb. In a second analysis across four classifications of curvature (straight, slight, medium, tight) advanced and experienced riders varied their lateral position more so than novices, though advanced riders had greater variation in lane position than even experienced riders in some conditions. The results suggest that experience and advanced training lead to changes in behaviour compared to novice riders which can be interpreted as having a potentially positive impact on road safety. PMID:25180786

  6. Coupling an analytical description of anti-scatter grids with simulation software of radiographic systems using Monte Carlo code

    International Nuclear Information System (INIS)

    The use of focused anti-scatter grids on digital radiographic systems with two-dimensional detectors produces acquisitions with a decreased scatter to primary ratio and thus improved contrast and resolution. Simulation software is of great interest in optimizing grid configuration according to a specific application. Classical simulators are based on complete detailed geometric descriptions of the grid. They are accurate but very time consuming since they use Monte Carlo code to simulate scatter within the high-frequency grids. We propose a new practical method which couples an analytical simulation of the grid interaction with a radiographic system simulation program. First, a two dimensional matrix of probability depending on the grid is created offline, in which the first dimension represents the angle of impact with respect to the normal to the grid lines and the other the energy of the photon. This matrix of probability is then used by the Monte Carlo simulation software in order to provide the final scattered flux image. To evaluate the gain of CPU time, we define the increasing factor as the increase of CPU time of the simulation with as opposed to without the grid. Increasing factors were calculated with the new model and with classical methods representing the grid with its CAD model as part of the object. With the new method, increasing factors are shorter by one to two orders of magnitude compared with the second one. These results were obtained with a difference in calculated scatter of less than five percent between the new and the classical method. (authors)

  7. Proposing "the burns suite" as a novel simulation tool for advancing the delivery of burns education.

    Science.gov (United States)

    Sadideen, Hazim; Wilson, David; Moiemen, Naiem; Kneebone, Roger

    2014-01-01

    Educational theory highlights the importance of contextualized simulation for effective learning. We explored this concept in a burns scenario in a novel, low-cost, high-fidelity, portable, immersive simulation environment (referred to as distributed simulation). This contextualized simulation/distributed simulation combination was named "The Burns Suite" (TBS). A pediatric burn resuscitation scenario was selected after high trainee demand. It was designed on Advanced Trauma and Life Support and Emergency Management of Severe Burns principles and refined using expert opinion through cognitive task analysis. TBS contained "realism" props, briefed nurses, and a simulated patient. Novices and experts were recruited. Five-point Likert-type questionnaires were developed for face and content validity. Cronbach's α was calculated for scale reliability. Semistructured interviews captured responses for qualitative thematic analysis allowing for data triangulation. Twelve participants completed TBS scenario. Mean face and content validity ratings were high (4.6 and 4.5, respectively; range, 4-5). The internal consistency of questions was high. Qualitative data analysis revealed that participants felt 1) the experience was "real" and they were "able to behave as if in a real resuscitation environment," and 2) TBS "addressed what Advanced Trauma and Life Support and Emergency Management of Severe Burns didn't" (including the efficacy of incorporating nontechnical skills). TBS provides a novel, effective simulation tool to significantly advance the delivery of burns education. Recreating clinical challenge is crucial to optimize simulation training. This low-cost approach also has major implications for surgical education, particularly during increasing financial austerity. Alternative scenarios and/or procedures can be recreated within TBS, providing a diverse educational immersive simulation experience. PMID:23877145

  8. Development of advanced driver assistance systems with vehicle hardware-in-the-loop simulations

    NARCIS (Netherlands)

    Gietelink, O.J.; Ploeg, J.; Schutter, B.de; Verhaegen, M.

    2006-01-01

    This paper presents a new method for the design and validation of advanced driver assistance systems (ADASs). With vehicle hardware-in-the-loop (VEHIL) simulations, the development process, and more specifically the validation phase, of intelligent vehicles is carried out safer, cheaper, and is more

  9. Analysis of simulation technique for steady shock waves in materials with analytical equations of state.

    Science.gov (United States)

    Reed, Evan J; Fried, Laurence E; Henshaw, William D; Tarver, Craig M

    2006-11-01

    We calculate and analyze a thermodynamic limit of a multiscale molecular dynamics based scheme that we have developed previously for simulating shock waves. We validate and characterize the performance of the former scheme for several simple cases. Using model equations of state for chemical reactions and kinetics in a gas and a condensed phase explosive, we show that detonation wave profiles computed using the computational scheme are in good agreement with the steady state wave profiles of hydrodynamic direct numerical simulations. We also characterize the stability of the technique when applied to detonation waves and describe a technique for determining the detonation shock speed. PMID:17280020

  10. Analytical simulation of nonlinear response to seismic test excitations of HDR-VKL [Heissdampfreaktor-Versuchskreislauf] piping system

    International Nuclear Information System (INIS)

    The paper describes the analytical modeling, calculations, and results of the posttest nonlinear simulation of high-level seismic testing of the VKL piping system at the HDR Test Facility in Germany. One of the objectives of the tests was to evaluate analytical methods for calculating the nonlinear response of realistic piping systems subjected to high-level seismic excitation that would induce significant plastic deformation. Two out of the six different pipe-support configurations, (ranging from a stiff system with struts and snubbers to a very flexible system with practically no seismic supports), subjected to simulated earthquakes, were tested at very high levels. The posttest nonlinear calculations cover the KWU configuration, a reasonably compliant system with only rigid struts. Responses for 800% safe-shutdown-earthquake loading were calculated using the NONPIPE code. The responses calculated with NONPIPE were found generally to have the same time trends as the measurements but contained under-, over-, and correct estimates of peak values, almost in equal proportions. The only exceptions were the peak strut forces, which were underestimated as a group. The scatter in the peak value estimate of displacements and strut forces was smaller than that for the strains. The possible reasons for the differences and the effort on further analysis are discussed

  11. Simulation research and optimal design for digital power regulating system of China advanced research reactor

    International Nuclear Information System (INIS)

    Based on SimPort simulation platform of nuclear power plant, a simulation model for Digital Power Regulating System (DPRS) of China Advanced Research Reactor (CARR) was established. By simulating the transient state of DPRS using this model, the adjusting parameters for the digital PID controller were determined. According to the features of the driving mechanism, the effects of the driving accuracy of the control rod and the displacement delay between electromagnetic coil and armature upon system stability and the regulating performance were analyzed, furthermore, their stability limit values were obtained respectively. The research results of this paper have some engineering practical value. (authors)

  12. Importance of Genetic Diversity Assessment in Crop Plants and Its Recent Advances: An Overview of Its Analytical Perspectives

    Directory of Open Access Journals (Sweden)

    M. Govindaraj

    2015-01-01

    Full Text Available The importance of plant genetic diversity (PGD is now being recognized as a specific area since exploding population with urbanization and decreasing cultivable lands are the critical factors contributing to food insecurity in developing world. Agricultural scientists realized that PGD can be captured and stored in the form of plant genetic resources (PGR such as gene bank, DNA library, and so forth, in the biorepository which preserve genetic material for long period. However, conserved PGR must be utilized for crop improvement in order to meet future global challenges in relation to food and nutritional security. This paper comprehensively reviews four important areas; (i the significance of plant genetic diversity (PGD and PGR especially on agriculturally important crops (mostly field crops; (ii risk associated with narrowing the genetic base of current commercial cultivars and climate change; (iii analysis of existing PGD analytical methods in pregenomic and genomic era; and (iv modern tools available for PGD analysis in postgenomic era. This discussion benefits the plant scientist community in order to use the new methods and technology for better and rapid assessment, for utilization of germplasm from gene banks to their applied breeding programs. With the advent of new biotechnological techniques, this process of genetic manipulation is now being accelerated and carried out with more precision (neglecting environmental effects and fast-track manner than the classical breeding techniques. It is also to note that gene banks look into several issues in order to improve levels of germplasm distribution and its utilization, duplication of plant identity, and access to database, for prebreeding activities. Since plant breeding research and cultivar development are integral components of improving food production, therefore, availability of and access to diverse genetic sources will ensure that the global food production network becomes more

  13. Capstone Teaching Models: Combining Simulation, Analytical Intuitive Learning Processes, History and Effectiveness

    Science.gov (United States)

    Reid, Maurice; Brown, Steve; Tabibzadeh, Kambiz

    2012-01-01

    For the past decade teaching models have been changing, reflecting the dynamics, complexities, and uncertainties of today's organizations. The traditional and the more current active models of learning have disadvantages. Simulation provides a platform to combine the best aspects of both types of teaching practices. This research explores the…

  14. Analytical Simulation of Flow and Heat Transfer of Two-Phase Nanofluid (Stratified Flow Regime

    Directory of Open Access Journals (Sweden)

    Mohammad Abbasi

    2014-01-01

    Full Text Available Nanofluids have evoked immense interest from researchers all around the globe due to their numerous potential benefits and applications in important fields such as cooling electronic parts, cooling car engines and nuclear reactors. An analytical study of fluid flow of in-tube stratified regime of two-phase nanofluid has been carried out for CuO, Al2O2, TiO3, and Au as applied nanoparticles in water as the base liquid. Liquid film thickness, convective heat transfer coefficient, and dryout length have been calculated. Among the considered nano particles, Al2O3 and TiO2 because of providing more amounts of heat transfer along with longer lengths of dryout found as the most appropriate nanoparticles to achieve cooling objectives.

  15. Joint multifractal analysis based on the partition function approach: analytical analysis, numerical simulation and empirical application

    Science.gov (United States)

    Xie, Wen-Jie; Jiang, Zhi-Qiang; Gu, Gao-Feng; Xiong, Xiong; Zhou, Wei-Xing

    2015-10-01

    Many complex systems generate multifractal time series which are long-range cross-correlated. Numerous methods have been proposed to characterize the multifractal nature of these long-range cross correlations. However, several important issues about these methods are not well understood and most methods consider only one moment order. We study the joint multifractal analysis based on partition function with two moment orders, which was initially invented to investigate fluid fields, and derive analytically several important properties. We apply the method numerically to binomial measures with multifractal cross correlations and bivariate fractional Brownian motions without multifractal cross correlations. For binomial multifractal measures, the explicit expressions of mass function, singularity strength and multifractal spectrum of the cross correlations are derived, which agree excellently with the numerical results. We also apply the method to stock market indexes and unveil intriguing multifractality in the cross correlations of index volatilities.

  16. A simple analytical scaling method for a scaled-down test facility simulating SB-LOCAs in a passive PWR

    International Nuclear Information System (INIS)

    A Simple analytical scaling method is developed for a scaled-down test facility simulating SB-LOCAs in a passive PWR. The whole scenario of a SB-LOCA is divided into two phases on the basis of the pressure trend ; depressurization phase and pot-boiling phase. The pressure and the core mixture level are selected as the most critical parameters to be preserved between the prototype and the scaled-down model. In each phase the high important phenomena having the influence on the critical parameters are identified and the scaling parameters governing the high important phenomena are generated by the present method. To validate the model used, Marviken CFT and 336 rod bundle experiment are simulated. The models overpredict both the pressure and two phase mixture level, but it shows agreement at least qualitatively with experimental results. In order to validate whether the scaled-down model well represents the important phenomena, we simulate the nondimensional pressure response of a cold-leg 4-inch break transient for AP-600 and the scaled-down model. The results of the present method are in excellent agreement with those of AP-600. It can be concluded that the present method is suitable for scaling the test facility simulating SB-LOCAs in a passive PWR

  17. Development of a VOR/DME model for an advanced concepts simulator

    Science.gov (United States)

    Steinmetz, G. G.; Bowles, R. L.

    1984-01-01

    The report presents a definition of a VOR/DME, airborne and ground systems simulation model. This description was drafted in response to a need in the creation of an advanced concepts simulation in which flight station design for the 1980 era can be postulated and examined. The simulation model described herein provides a reasonable representation of VOR/DME station in the continental United States including area coverage by type and noise errors. The detail in which the model has been cast provides the interested researcher with a moderate fidelity level simulator tool for conducting research and evaluation of navigator algorithms. Assumptions made within the development are listed and place certain responsibilities (data bases, communication with other simulation modules, uniform round earth, etc.) upon the researcher.

  18. Advanced manned space flight simulation and training: An investigation of simulation host computer system concepts

    Science.gov (United States)

    Montag, Bruce C.; Bishop, Alfred M.; Redfield, Joe B.

    1989-01-01

    The findings of a preliminary investigation by Southwest Research Institute (SwRI) in simulation host computer concepts is presented. It is designed to aid NASA in evaluating simulation technologies for use in spaceflight training. The focus of the investigation is on the next generation of space simulation systems that will be utilized in training personnel for Space Station Freedom operations. SwRI concludes that NASA should pursue a distributed simulation host computer system architecture for the Space Station Training Facility (SSTF) rather than a centralized mainframe based arrangement. A distributed system offers many advantages and is seen by SwRI as the only architecture that will allow NASA to achieve established functional goals and operational objectives over the life of the Space Station Freedom program. Several distributed, parallel computing systems are available today that offer real-time capabilities for time critical, man-in-the-loop simulation. These systems are flexible in terms of connectivity and configurability, and are easily scaled to meet increasing demands for more computing power.

  19. Advanced Simulation of Coupled Earthquake and Tsunami Events (ASCETE) - Simulation Techniques for Realistic Tsunami Process Studies

    Science.gov (United States)

    Behrens, Joern; Bader, Michael; Breuer, Alexander N.; van Dinther, Ylona; Gabriel, Alice-A.; Galvez Barron, Percy E.; Rahnema, Kaveh; Vater, Stefan; Wollherr, Stephanie

    2015-04-01

    At the End of phase 1 of the ASCETE project a simulation framework for coupled physics-based rupture generation with tsunami propagation and inundation is available. Adaptive mesh tsunami propagation and inundation by discontinuous Galerkin Runge-Kutta methods allows for accurate and conservative inundation schemes. Combined with a tree-based refinement strategy to highly optimize the code for high-performance computing architectures, a modeling tool for high fidelity tsunami simulations has been constructed. Validation results demonstrate the capacity of the software. Rupture simulation is performed by an unstructured tetrahedral discontinuous Galerking ADER discretization, which allows for accurate representation of complex geometries. The implemented code was nominated for and was selected as a finalist for the Gordon Bell award in high-performance computing. Highly realistic rupture events can be simulated with this modeling tool. The coupling of rupture induced wave activity and displacement with hydrodynamic equations still poses a major problem due to diverging time and spatial scales. Some insight from the ASCETE set-up could be gained and the presentation will focus on the coupled behavior of the simulation system. Finally, an outlook to phase 2 of the ASCETE project will be given in which further development of detailed physical processes as well as near-realistic scenario computations are planned. ASCETE is funded by the Volkswagen Foundation.

  20. Advances in the simulation and automated measurement of well-sorted granular material: 1. Simulation

    Science.gov (United States)

    Daniel Buscombe; Rubin, David M.

    2012-01-01

    1. In this, the first of a pair of papers which address the simulation and automated measurement of well-sorted natural granular material, a method is presented for simulation of two-phase (solid, void) assemblages of discrete non-cohesive particles. The purpose is to have a flexible, yet computationally and theoretically simple, suite of tools with well constrained and well known statistical properties, in order to simulate realistic granular material as a discrete element model with realistic size and shape distributions, for a variety of purposes. The stochastic modeling framework is based on three-dimensional tessellations with variable degrees of order in particle-packing arrangement. Examples of sediments with a variety of particle size distributions and spatial variability in grain size are presented. The relationship between particle shape and porosity conforms to published data. The immediate application is testing new algorithms for automated measurements of particle properties (mean and standard deviation of particle sizes, and apparent porosity) from images of natural sediment, as detailed in the second of this pair of papers. The model could also prove useful for simulating specific depositional structures found in natural sediments, the result of physical alterations to packing and grain fabric, using discrete particle flow models. While the principal focus here is on naturally occurring sediment and sedimentary rock, the methods presented might also be useful for simulations of similar granular or cellular material encountered in engineering, industrial and life sciences.

  1. Analytical Simulation and Performance Optimization for Spectrum Sensing in Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    Ayman A. El-Saleh

    2011-02-01

    Full Text Available Dynamic spectrum allocation (DSA solutions such as cognitive radio networks (CRNs have been proposed as a key technology to exploit the frequency segments that are spectrally underutilized. In this paper, the performance of cooperative CRNs has been analyzed under two different operational modes, namely, constant primary user protection (CPUP and constant secondary user spectrum usability (CSUSU. The CRN performance metrics have been selected to be the overall CRN capacity and the overall interference from CRN to the primary users under CPUP and CSUSU scenario, respectively. Computer simulations are invoked to evaluate the CRN performance with varying the sensing time as well as the number of cooperating users in the network and the observations have been presented. Finally, particle swarm ptimization algorithm has been used to jointly optimize the sensing time duration and cooperation level of spectrum sensing in CRNs. The simulation results show that the CRN performance can be noticeably improved by applying suitable optimization algorithms.

  2. Advancement of DOE's EnergyPlus Building Energy Simulation Payment

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Lixing [Florida Solar Energy Center, Cocoa, FL (United States); Shirey, Don [Florida Solar Energy Center, Cocoa, FL (United States); Raustad, Richard [Florida Solar Energy Center, Cocoa, FL (United States); Nigusse, Bereket [Florida Solar Energy Center, Cocoa, FL (United States); Sharma, Chandan [Florida Solar Energy Center, Cocoa, FL (United States); Lawrie, Linda [DHL Consulting, Bonn (Germany); Strand, Rick [Univ. of Illinois, Champaign, IL (United States); Pedersen, Curt [COPA, Panama City (Panama); Fisher, Dan [Oklahoma State Univ., Stillwater, OK (United States); Lee, Edwin [Oklahoma State Univ., Stillwater, OK (United States); Witte, Mike [GARD Analytics, Arlington Heights, IL (United States); Glazer, Jason [GARD Analytics, Arlington Heights, IL (United States); Barnaby, Chip [Wrightsoft, Lexington, MA (United States)

    2011-09-30

    EnergyPlus{sup TM} is a new generation computer software analysis tool that has been developed, tested, and commercialized to support DOE's Building Technologies (BT) Program in terms of whole-building, component, and systems R&D (http://www.energyplus.gov). It is also being used to support evaluation and decision making of zero energy building (ZEB) energy efficiency and supply technologies during new building design and existing building retrofits. The 5-year project was managed by the National Energy Technology Laboratory and was divided into 5 budget period between 2006 and 2011. During the project period, 11 versions of EnergyPlus were released. This report summarizes work performed by an EnergyPlus development team led by the University of Central Florida's Florida Solar Energy Center (UCF/FSEC). The team members consist of DHL Consulting, C. O. Pedersen Associates, University of Illinois at Urbana-Champaign, Oklahoma State University, GARD Analytics, Inc., and WrightSoft Corporation. The project tasks involved new feature development, testing and validation, user support and training, and general EnergyPlus support. The team developed 146 new features during the 5-year period to advance the EnergyPlus capabilities. Annual contributions of new features are 7 in budget period 1, 19 in period 2, 36 in period 3, 41 in period 4, and 43 in period 5, respectively. The testing and validation task focused on running test suite and publishing report, developing new IEA test suite cases, testing and validating new source code, addressing change requests, and creating and testing installation package. The user support and training task provided support for users and interface developers, and organized and taught workshops. The general support task involved upgrading StarTeam (team sharing) software and updating existing utility software. The project met the DOE objectives and completed all tasks successfully. Although the EnergyPlus software was enhanced

  3. The Osmotic Coefficient of Rod-like Polyelectrolytes: Computer Simulation, Analytical Theory, and Experiment

    OpenAIRE

    Deserno, M.; Holm, C; Blaul, J.; Ballauff, M.; Rehahn, M.

    2001-01-01

    The osmotic coefficient of solutions of rod-like polyelectrolytes is considered by comparing current theoretical treatments and simulations to recent experimental data. The discussion is restricted to the case of monovalent counterions and dilute, salt-free solutions. The classical Poisson-Boltzmann solution of the cell model correctly predicts a strong decrease in the osmotic coefficient, but upon closer look systematically overestimates its value. The contribution of ion-ion-correlations ar...

  4. Diffusion processes in biological membranes studied by molecular dynamics simulations and analytical models

    OpenAIRE

    Stachura, Slawomir,

    2014-01-01

    Various recent experimental and simulation studies show that the lateral diffusion of molecules in biological membranes exhibits anomalies, in the sense that the molecular mean square displacements increase sub-linearily instead of linearly with time. Mathematically, such diffusion processes can be modeled by generalized diffusion equations which involve an additional fractional time derivative compared to the corresponding normal counterpart. The aim of this thesis is to gain some more physi...

  5. Editorial: Advances in Health Education Applying E-Learning, Simulations and Distance Technologies

    Directory of Open Access Journals (Sweden)

    Andre W. Kushniruk

    2011-03-01

    Full Text Available This special issue of the KM&EL international journal is dedicated to coverage of novel advances in health professional education applying e-Learning, simulations and distance education technologies. Modern healthcare is beginning to be transformed through the emergence of new information technologies and rapid advances in health informatics. Advances such as electronic health record systems (EHRs, clinical decision support systems and other advanced information systems such as public health surveillance systems are rapidly being deployed worldwide. The education of health professionals such as medical, nursing and allied health professionals will require an improved understanding of these technologies and how they will transform their healthcare practice. However, currently there is a lack of integration of knowledge and skills related to such technology in health professional education. In this issue of the journal we present articles that describe a set of novel approaches to integrating essential health information technology into the education of health professionals, as well as the use of advanced information technologies and e-Learning approaches for improving health professional education. The approaches range from use of simulations to development of novel Web-based platforms for allowing students to interact with the technologies and healthcare practices that are rapidly changing healthcare.

  6. Silicon heterojunction solar cells: Optimization of emitter and contact properties from analytical calculation and numerical simulation

    International Nuclear Information System (INIS)

    Highlights: ► We relate the open circuit voltage and the band-bending in crystalline silicon. ► We calculate the band-bending in the crystalline part of a silicon heterojunction. ► The band-bending is strongly influenced by the work function and density of states. ► A high defect density in the amorphous silicon emitter increases the band bending. ► A high defect density reduces the impact of the contact on the open circuit voltage. -- Abstract: The key constituent of silicon heterojunction solar cells, the amorphous silicon/crystalline silicon heterojunction (a-Si:H/c-Si), offers a high open-circuit voltage (Voc) potential providing that both the interface defect passivation and the band bending in the c-Si absorber are sufficient. We detail here analytical calculations of the equilibrium band bending in c-Si (ψc-Si) in Transparent Conductive Oxide (TCO)/a-Si:H emitter/c-Si absorber structures. We studied the variation of some electronic parameters (density of states, work function) according to relevant experimental values. This study introduces a discussion on the optimization of the doped emitter layer in relation with the work function of the TCO. In particular, we argue on the advantage of having a highly defective (p)a-Si:H emitter layer that maximizes ψc-Si and reduces the influence of the TCO on Voc

  7. The role of numerical simulation for the development of an advanced HIFU system

    Science.gov (United States)

    Okita, Kohei; Narumi, Ryuta; Azuma, Takashi; Takagi, Shu; Matumoto, Yoichiro

    2014-10-01

    High-intensity focused ultrasound (HIFU) has been used clinically and is under clinical trials to treat various diseases. An advanced HIFU system employs ultrasound techniques for guidance during HIFU treatment instead of magnetic resonance imaging in current HIFU systems. A HIFU beam imaging for monitoring the HIFU beam and a localized motion imaging for treatment validation of tissue are introduced briefly as the real-time ultrasound monitoring techniques. Numerical simulations have a great impact on the development of real-time ultrasound monitoring as well as the improvement of the safety and efficacy of treatment in advanced HIFU systems. A HIFU simulator was developed to reproduce ultrasound propagation through the body in consideration of the elasticity of tissue, and was validated by comparison with in vitro experiments in which the ultrasound emitted from the phased-array transducer propagates through the acrylic plate acting as a bone phantom. As the result, the defocus and distortion of the ultrasound propagating through the acrylic plate in the simulation quantitatively agree with that in the experimental results. Therefore, the HIFU simulator accurately reproduces the ultrasound propagation through the medium whose shape and physical properties are well known. In addition, it is experimentally confirmed that simulation-assisted focus control of the phased-array transducer enables efficient assignment of the focus to the target. Simulation-assisted focus control can contribute to design of transducers and treatment planning.

  8. The Osseus platform: a prototype for advanced web-based distributed simulation

    Science.gov (United States)

    Franceschini, Derrick; Riecken, Mark

    2016-05-01

    Recent technological advances in web-based distributed computing and database technology have made possible a deeper and more transparent integration of some modeling and simulation applications. Despite these advances towards true integration of capabilities, disparate systems, architectures, and protocols will remain in the inventory for some time to come. These disparities present interoperability challenges for distributed modeling and simulation whether the application is training, experimentation, or analysis. Traditional approaches call for building gateways to bridge between disparate protocols and retaining interoperability specialists. Challenges in reconciling data models also persist. These challenges and their traditional mitigation approaches directly contribute to higher costs, schedule delays, and frustration for the end users. Osseus is a prototype software platform originally funded as a research project by the Defense Modeling & Simulation Coordination Office (DMSCO) to examine interoperability alternatives using modern, web-based technology and taking inspiration from the commercial sector. Osseus provides tools and services for nonexpert users to connect simulations, targeting the time and skillset needed to successfully connect disparate systems. The Osseus platform presents a web services interface to allow simulation applications to exchange data using modern techniques efficiently over Local or Wide Area Networks. Further, it provides Service Oriented Architecture capabilities such that finer granularity components such as individual models can contribute to simulation with minimal effort.

  9. A Comprehensive Comparison between Wave Propagation and Heat Distribution via Analytical Solutions and Computer Simulations

    Directory of Open Access Journals (Sweden)

    Ramin Shamshiri

    2014-01-01

    Full Text Available Wave propagation and heat distribution are both governed by second order linear constant coefficient partial differential equations, however their solutions yields very different properties. This study presents a comprehensive comparison between hyperbolic wave equation and parabolic heat equation. Issues such as conservation of wave profile versus averaging, transporting information, finite versus infinite speed propagation, time reversibility versus irreversibility and propagation of singularities versus instantaneous smoothing have been addressed and followed by examples and graphical evidences from computer simulations to support the arguments.

  10. FY05-FY06 Advanced Simulation and Computing Implementation Plan, Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Baron, A L

    2004-07-19

    The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the safety and reliability of the U.S. nuclear stockpile. The SSP uses past nuclear test data along with future non-nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program will require the continued use of current facilities and programs along with new experimental facilities and computational enhancements to support these programs. The Advanced Simulation and Computing program (ASC) is a cornerstone of the SSP, providing simulation capabilities and computational resources to support the annual stockpile assessment and certification, to study advanced nuclear weapon design and manufacturing processes, to analyze accident scenarios and weapons aging, and to provide the tools to enable stockpile life extension programs and the resolution of significant finding investigations (SFIs). This requires a balanced system of technical staff, hardware, simulation software, and computer science solutions.

  11. Evaluating analytical approaches for estimating pelagic fish biomass using simulated fish communities

    Science.gov (United States)

    Yule, Daniel L.; Adams, Jean V.; Warner, David M.; Hrabik, Thomas R.; Kocovsky, Patrick M.; Weidel, Brian C.; Rudstam, Lars G.; Sullivan, Patrick J.

    2013-01-01

    Pelagic fish assessments often combine large amounts of acoustic-based fish density data and limited midwater trawl information to estimate species-specific biomass density. We compared the accuracy of five apportionment methods for estimating pelagic fish biomass density using simulated communities with known fish numbers that mimic Lakes Superior, Michigan, and Ontario, representing a range of fish community complexities. Across all apportionment methods, the error in the estimated biomass generally declined with increasing effort, but methods that accounted for community composition changes with water column depth performed best. Correlations between trawl catch and the true species composition were highest when more fish were caught, highlighting the benefits of targeted trawling in locations of high fish density. Pelagic fish surveys should incorporate geographic and water column depth stratification in the survey design, use apportionment methods that account for species-specific depth differences, target midwater trawling effort in areas of high fish density, and include at least 15 midwater trawls. With relatively basic biological information, simulations of fish communities and sampling programs can optimize effort allocation and reduce error in biomass estimates.

  12. Scale model test and analytical simulation on steam injector driven passive core injection system

    International Nuclear Information System (INIS)

    A reactor, such as ESBWR, equipped with the passive safety system by gravity-driven cooling system (GDCS) and the depressurization valves (DPVs) should be inevitable to lead to large LOCA even for the case of small LOCA by forcibly opening the DPVs to inject water from the GDCS pool due to that the DGCS water head is up to ∼0.2MPa. Meanwhile, a steam injector (SI) is a simple, compact and passive jet pump. The passive core injection system (PCIS) driven by high-efficiency SI is a system that, in an accident such as a LOCA, attains discharge pressure higher than the supply steam pressure to inject water into the reactor by operating the SI, by supplying water from a pool in a containment vessel and the steam from a reactor pressure vessel. We simulated and evaluated the core cooling and water injection performance of SI-PCIS in BWR using RETRAN-3D code for the case of small LOCA. Our simulation exhibited that SI-PCIS could save the reactors from leading to large LOCA by discharge of the water into a core for the cases of small LOCA or DPV unexpectedly open. In addition, we conducted the full-scale SI analysis using the SI characteristic analysis model. (author)

  13. Analytical calculation of in-plane response of plates with concentrated masses to impact and application to pyroshock simulation

    Science.gov (United States)

    Lacher, Alexander; Jüngel, Nikolas; von Wagner, Utz; Bäger, Annette

    2012-07-01

    In aerospace missions pyroshocks occur due to controlled explosions of ordnance devices enabling the functionality of space modules. These shocks result from deployment mechanisms or opening solar sails and can cause failures of electronic devices and structures. Thus, essential components for assuring the reliability of modules are pyroshock tests for the completion of which strict requirements by the aerospace administrations have to be met. One of them is the definition of a specific acceleration signal and, based on this, the Shock Response Spectrum (SRS) for each part. So far, there is rather empirical than analytical knowledge about producing desired SRS with mechanical impacts and its characteristics due to the variation of input parameters. In this paper a widespread testing procedure for far-field pyroshocks is discussed which is realized by the in-plane impact of a hammer pendulum on a plate including the test specimen. The mechanical model consists of the contact between a rigid sphere and a free deformable rectangular plate with attached masses including subsequent propagation and reflection of longitudinal waves. In order to allow for a prediction of the acceleration field and the corresponding SRS due to the impact the problem is solved semi-analytically by using Hertzian contact theory, the Galerkin-procedure and numerical integration in time domain. The in-plane problem has, to the best of the authors' knowledge, not yet been treated in the literature in the way presented. The results calculated are compared with experimental data showing very good coincidence and allowing for a fast prediction of far-field pyroshock tests due to the impact excitation by a hammer pendulum. Hence, the framework of this paper is an enrichment for the current state of the art considering analytical pyroshock simulation. By better understanding the effect of pyroshocks to one and two dimensional structures a reduction of costs as well as durations for testing procedures

  14. Harmonic Oscillator in Heat Bath: Exact simulation of time-lapse-recorded data, exact analytical benchmark statistics

    CERN Document Server

    Norrelykke, Simon F

    2011-01-01

    The stochastic dynamics of the damped harmonic oscillator in a heat bath is simulated with an algorithm that is exact for time steps of arbitrary size. Exact analytical results are given for correlation functions and power spectra in the form they acquire when computed from experimental time-lapse recordings. Three applications are discussed: (i) Effects of finite sampling-rate and -time, described exactly here, are similar for other stochastic dynamical systems-e.g. motile micro-organisms and their time-lapse recorded trajectories. (ii) The same statistics is satisfied by any experimental system to the extent it is interpreted as a damped harmonic oscillator at finite temperature-such as an AFM cantilever. (iii) Three other models of fundamental interest are limiting cases of the damped harmonic oscillator at finite temperature; it consequently bridges their differences and describes effects of finite sampling rate and sampling time for these models as well. Finally, we give a brief discussion of nondimensio...

  15. Development and application of functional-analytic simulator in the training of nuclear power plant operating personnel

    International Nuclear Information System (INIS)

    The experience is reviewed from the development and utilization of a functional-analytic training simulator used in the USSR for training the personnel of nuclear power plants with WWER-1000 reactors. The training facility consists of a central ES 1066 computer where the mathematical model of the power unit is implemented, and of four teaching workplaces with Elektronika-85 personal computers. An Elektronika-60 computer links these computers to the central unit. The training facility enables reactor operators to practise in understanding dynamic power unit characteristics and relations between dynamic parameters, to gain basic skills for unit control with respect to limitations following from nuclear safety requirements, to master non-standard situations and to perform analyses of accidents. The facility is also used to check the professional skills of operators and to provide preliminary training prior to switching over to full-scale training facilities. (Z.M.). 2 refs

  16. Scattering of electromagnetic waves by vortex density structures associated with interchange instability: Analytical and large scale plasma simulation results

    Energy Technology Data Exchange (ETDEWEB)

    Sotnikov, V.; Kim, T.; Lundberg, J. [Air Force Research Laboratory (AFRL/RY), Wright Patterson AFB, Ohio 45433 (United States); Paraschiv, I. [University of Nevada at Reno, Nevada 89557 (United States); Mehlhorn, T. A. [Naval Research Laboratory, Washington, District of Columbia 20375 (United States)

    2014-05-15

    The presence of plasma turbulence can strongly influence propagation properties of electromagnetic signals used for surveillance and communication. In particular, we are interested in the generation of low frequency plasma density irregularities in the form of coherent vortex structures. Interchange or flute type density irregularities in magnetized plasma are associated with Rayleigh-Taylor type instability. These types of density irregularities play an important role in refraction and scattering of high frequency electromagnetic signals propagating in the earth ionosphere, in high energy density physics, and in many other applications. We will discuss scattering of high frequency electromagnetic waves on low frequency density irregularities due to the presence of vortex density structures associated with interchange instability. We will also present particle-in-cell simulation results of electromagnetic scattering on vortex type density structures using the large scale plasma code LSP and compare them with analytical results.

  17. Advanced simulation technology for etching process design for CMOS device applications

    Science.gov (United States)

    Kuboi, Nobuyuki; Fukasawa, Masanaga; Tatsumi, Tetsuya

    2016-07-01

    Plasma etching is a critical process for the realization of high performance in the next generation of CMOS devices. To predict and control fluctuations in the etching properties accurately during mass production, it is essential that etching process simulation technology considers fluctuations in the plasma chamber wall conditions, the effects of by-products on the critical dimensions, the Si recess dependence on the wafer open area ratio and local pattern structure, and the time-dependent plasma-induced damage distribution associated with the three-dimensional feature scale profile at the 100 nm level. This consideration can overcome the issues with conventional simulations performed under the assumed ideal conditions, which are not accurate enough for practical process design. In this article, these advanced process simulation technologies are reviewed, and, from the results of suitable process simulations, a new etching system that automatically controls the etching properties is proposed to enable stable CMOS device fabrication with high yields.

  18. Nanocrystalline material in toroidal cores for current transformer: analytical study and computational simulations

    Directory of Open Access Journals (Sweden)

    Benedito Antonio Luciano

    2005-12-01

    Full Text Available Based on electrical and magnetic properties, such as saturation magnetization, initial permeability, and coercivity, in this work are presented some considerations about the possibilities of applications of nanocrystalline alloys in toroidal cores for current transformers. It is discussed how the magnetic characteristics of the core material affect the performance of the current transformer. From the magnetic characterization and the computational simulations, using the finite element method (FEM, it has been verified that, at the typical CT operation value of flux density, the nanocrystalline alloys properties reinforce the hypothesis that the use of these materials in measurement CT cores can reduce the ratio and phase errors and can also improve its accuracy class.

  19. CAPE-OPEN Integration for Advanced Process Engineering Co-Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Zitney, S.E.

    2006-11-01

    This paper highlights the use of the CAPE-OPEN (CO) standard interfaces in the Advanced Process Engineering Co-Simulator (APECS) developed at the National Energy Technology Laboratory (NETL). The APECS system uses the CO unit operation, thermodynamic, and reaction interfaces to provide its plug-and-play co-simulation capabilities, including the integration of process simulation with computational fluid dynamics (CFD) simulation. APECS also relies heavily on the use of a CO COM/CORBA bridge for running process/CFD co-simulations on multiple operating systems. For process optimization in the face of multiple and some time conflicting objectives, APECS offers stochastic modeling and multi-objective optimization capabilities developed to comply with the CO software standard. At NETL, system analysts are applying APECS to a wide variety of advanced power generation systems, ranging from small fuel cell systems to commercial-scale power plants including the coal-fired, gasification-based FutureGen power and hydrogen production plant.

  20. The advanced simulation of fatigue crack growth in complex 3D structures

    Energy Technology Data Exchange (ETDEWEB)

    Kolk, Karsten; Kuhn, Guenther [Institute of Applied Mechanics, Erlangen (Germany)

    2006-12-15

    An advanced incremental crack growth algorithm for the three-dimensional (3D) simulation of fatigue crack growth in complex 3D structures with linear elastic material behavior is presented. To perform the crack growth simulation as effectively as possible an accurate stress analysis is done by the boundary-element method (BEM) in terms of the 3D dual BEM. The question concerning a reliable 3D crack growth criterion is answered based on experimental observations. All criteria under consideration are numerically realized by a predictor-corrector procedure. The agreement between numerically determined and experimentally observed crack fronts will be shown on both fracture specimens and an industrial application. (orig.)

  1. Advanced Simulation and Computing FY10-11 Implementation Plan Volume 2, Rev. 0

    Energy Technology Data Exchange (ETDEWEB)

    Carnes, B

    2009-06-08

    The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the surety and reliability of the U.S. nuclear stockpile. The SSP uses past nuclear test data along with current and future non-nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of current facilities and programs along with new experimental facilities and computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC) is a cornerstone of the SSP, providing simulation capabilities and computational resources to support the annual stockpile assessment and certification, to study advanced nuclear weapons design and manufacturing processes, to analyze accident scenarios and weapons aging, and to provide the tools to enable stockpile Life Extension Programs (LEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balanced resource, including technical staff, hardware, simulation software, and computer science solutions. In its first decade, the ASC strategy focused on demonstrating simulation capabilities of unprecedented scale in three spatial dimensions. In its second decade, ASC is focused on increasing its predictive capabilities in a three-dimensional simulation environment while maintaining support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (focused on sufficient resolution, dimensionality and scientific details); to quantify critical margins and uncertainties (QMU); and to resolve increasingly difficult analyses needed for the SSP. Moreover, ASC has restructured its business model from one that

  2. Advanced Simulation and Computing FY09-FY10 Implementation Plan, Volume 2, Revision 0.5

    Energy Technology Data Exchange (ETDEWEB)

    Meisner, R; Hopson, J; Peery, J; McCoy, M

    2008-10-07

    The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the surety and reliability of the U.S. nuclear stockpile. The SSP uses past nuclear test data along with current and future non-nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of current facilities and programs along with new experimental facilities and computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC)1 is a cornerstone of the SSP, providing simulation capabilities and computational resources to support the annual stockpile assessment and certification, to study advanced nuclear weapons design and manufacturing processes, to analyze accident scenarios and weapons aging, and to provide the tools to enable stockpile Life Extension Programs (LEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balanced resource, including technical staff, hardware, simulation software, and computer science solutions. In its first decade, the ASC strategy focused on demonstrating simulation capabilities of unprecedented scale in three spatial dimensions. In its second decade, ASC is focused on increasing its predictive capabilities in a three-dimensional simulation environment while maintaining support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (focused on sufficient resolution, dimensionality and scientific details); to quantify critical margins and uncertainties (QMU); and to resolve increasingly difficult analyses needed for the SSP. Moreover, ASC has restructured its business model from one

  3. Advanced Simulation and Computing FY09-FY10 Implementation Plan Volume 2, Rev. 1

    Energy Technology Data Exchange (ETDEWEB)

    Kissel, L

    2009-04-01

    The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the surety and reliability of the U.S. nuclear stockpile. The SSP uses past nuclear test data along with current and future non-nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of current facilities and programs along with new experimental facilities and computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC) is a cornerstone of the SSP, providing simulation capabilities and computational resources to support the annual stockpile assessment and certification, to study advanced nuclear weapons design and manufacturing processes, to analyze accident scenarios and weapons aging, and to provide the tools to enable stockpile Life Extension Programs (LEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balanced resource, including technical staff, hardware, simulation software, and computer science solutions. In its first decade, the ASC strategy focused on demonstrating simulation capabilities of unprecedented scale in three spatial dimensions. In its second decade, ASC is focused on increasing its predictive capabilities in a three-dimensional simulation environment while maintaining support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (focused on sufficient resolution, dimensionality and scientific details); to quantify critical margins and uncertainties (QMU); and to resolve increasingly difficult analyses needed for the SSP. Moreover, ASC has restructured its business model from one that

  4. Advanced Simulation and Computing FY10-FY11 Implementation Plan Volume 2, Rev. 0.5

    Energy Technology Data Exchange (ETDEWEB)

    Meisner, R; Peery, J; McCoy, M; Hopson, J

    2009-09-08

    The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the surety and reliability of the U.S. nuclear stockpile. The SSP uses past nuclear test data along with current and future non-nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering (D&E) programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of current facilities and programs along with new experimental facilities and computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC) is a cornerstone of the SSP, providing simulation capabilities and computational resources to support the annual stockpile assessment and certification, to study advanced nuclear weapons design and manufacturing processes, to analyze accident scenarios and weapons aging, and to provide the tools to enable stockpile Life Extension Programs (LEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balanced resource, including technical staff, hardware, simulation software, and computer science solutions. In its first decade, the ASC strategy focused on demonstrating simulation capabilities of unprecedented scale in three spatial dimensions. In its second decade, ASC is focused on increasing its predictive capabilities in a three-dimensional (3D) simulation environment while maintaining support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (focused on sufficient resolution, dimensionality and scientific details); to quantify critical margins and uncertainties (QMU); and to resolve increasingly difficult analyses needed for the SSP. Moreover, ASC has restructured its business model

  5. Advanced Simulation and Computing FY08-09 Implementation Plan, Volume 2, Revision 0.5

    Energy Technology Data Exchange (ETDEWEB)

    Kusnezov, D; Bickel, T; McCoy, M; Hopson, J

    2007-09-13

    The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the surety and reliability of the U.S. nuclear stockpile. The SSP uses past nuclear test data along with current and future non-nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of current facilities and programs along with new experimental facilities and computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC)1 is a cornerstone of the SSP, providing simulation capabilities and computational resources to support the annual stockpile assessment and certification, to study advanced nuclear-weapons design and manufacturing processes, to analyze accident scenarios and weapons aging, and to provide the tools to enable Stockpile Life Extension Programs (SLEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balanced resource, including technical staff, hardware, simulation software, and computer science solutions. In its first decade, the ASC strategy focused on demonstrating simulation capabilities of unprecedented scale in three spatial dimensions. In its second decade, ASC is focused on increasing its predictive capabilities in a three-dimensional simulation environment while maintaining the support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (focused on sufficient resolution, dimensionality and scientific details); to quantify critical margins and uncertainties (QMU); and to resolve increasingly difficult analyses needed for the SSP. Moreover, ASC has restructured its business model from

  6. Advanced Simulation and Computing FY08-09 Implementation Plan Volume 2 Revision 0

    Energy Technology Data Exchange (ETDEWEB)

    McCoy, M; Kusnezov, D; Bikkel, T; Hopson, J

    2007-04-25

    The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the safety and reliability of the U.S. nuclear stockpile. The SSP uses past nuclear test data along with current and future nonnuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of current facilities and programs along with new experimental facilities and computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC) is a cornerstone of the SSP, providing simulation capabilities and computational resources to support the annual stockpile assessment and certification, to study advanced nuclear-weapons design and manufacturing processes, to analyze accident scenarios and weapons aging, and to provide the tools to enable Stockpile Life Extension Programs (SLEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balanced resource, including technical staff, hardware, simulation software, and computer science solutions. In its first decade, the ASC strategy focused on demonstrating simulation capabilities of unprecedented scale in three spatial dimensions. In its second decade, ASC is focused on increasing its predictive capabilities in a three-dimensional simulation environment while maintaining the support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (focused on sufficient resolution, dimensionality and scientific details); to quantify critical margins and uncertainties (QMU); and to resolve increasingly difficult analyses needed for the SSP. Moreover, ASC has restructured its business model from one

  7. Advanced Simulation and Computing FY07-08 Implementation Plan Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Kusnezov, D; Hale, A; McCoy, M; Hopson, J

    2006-06-22

    The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the safety and reliability of the U.S. nuclear stockpile. The SSP uses past nuclear test data along with current and future nonnuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program will require the continued use of current facilities and programs along with new experimental facilities and computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC) is a cornerstone of the SSP, providing simulation capabilities and computational resources to support the annual stockpile assessment and certification, to study advanced nuclear-weapons design and manufacturing processes, to analyze accident scenarios and weapons aging, and to provide the tools to enable Stockpile Life Extension Programs (SLEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balanced resource, including technical staff, hardware, simulation software, and computer science solutions. In its first decade, the ASC strategy focused on demonstrating simulation capabilities of unprecedented scale in three spatial dimensions. In its second decade, ASC is focused on increasing its predictive capabilities in a three-dimensional simulation environment while maintaining the support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (focused on sufficient resolution, dimensionality and scientific details); to quantify critical margins and uncertainties (QMU); and to resolve increasingly difficult analyses needed for the SSP. Moreover, ASC has restructured its business model from

  8. CFD Simulations of a Regenerative Process for Carbon Dioxide Capture in Advanced Gasification Based Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Arastoopour, Hamid [Illinois Inst. of Technology, Chicago, IL (United States); Abbasian, Javad [Illinois Inst. of Technology, Chicago, IL (United States)

    2014-07-31

    the method of moments, called Finite size domain Complete set of trial functions Method Of Moments (FCMOM) was used to solve the population balance equations. The PBE model was implemented in a commercial CFD code, Ansys Fluent 13.0. The code was used to test the model in some simple cases and the results were verified against available analytical solution in the literature. Furthermore, the code was used to simulate CO2 capture in a packed-bed and the results were in excellent agreement with the experimental data obtained in the packed bed. The National Energy Laboratory (NETL) Carbon Capture Unit (C2U) design was used in simulate of the hydrodynamics of the cold flow gas/solid system (Clark et al.58). The results indicate that the pressure drop predicted by the model is in good agreement with the experimental data. Furthermore, the model was shown to be able to predict chugging behavior, which was observed during the experiment. The model was used as a base-case for simulations of reactive flow at elevated pressure and temperatures. The results indicate that by controlling the solid circulation rate, up to 70% CO2 removal can be achieved and that the solid hold up in the riser is one of the main factors controlling the extent of CO2 removal. The CFD/PBE simulation model indicates that by using a simulated syngas with a composition of 20% CO2, 20% H2O, 30% CO, and 30% H2, the composition (wet basis) in the reactor outlet corresponded to about 60% CO2 capture with and exit gas containing 65% H2. A preliminary base-case-design was developed for a regenerative MgO-based pre-combustion carbon capture process for a 500 MW IGCC power plant. To minimize the external energy requirement, an extensive heat integration network was developed in Aspen/HYSYS® to produce the steam required in the regenerator and heat integration. In this process, liquid CO2 produced at 50 atm can easily be pumped and sequestered or stored. The preliminary economic analyses indicate that the

  9. Numerical Simulation of Polarity Characteristics of Vector Elastic Wave of Advanced Detection in the Roadway

    OpenAIRE

    Deng Shuaiqi; Yue Jianhua; Cao Jing; Zhang Xin

    2013-01-01

    The high-order staggering grid Finite-Difference (FD) scheme based on first-order velocity-stress elastic wave equation has been deduced. The calculation method of PML boundary condition and stability condition established in this study can be used for numerical simulation of advanced detection of elastic wave in roadway, with the obtaining of high-precision seismogram. Then we systematically analyze the polarity of vector wave field in post-source observation system. The results indicate tha...

  10. Impact noise radiated by collision of two spheres: Comparison between numerical simulations, experiments and analytical results

    International Nuclear Information System (INIS)

    Impact is very common source of noise in the industries. The impacts can be visible, such as forging, and can be invisible, such as impacts due to clearance of hinges. As a result of this generality, the control of impact noise needs more attention. Reduction of this tiresome noise needs enough perception about the impact. A study of this noise sources presents difficult problems both theoretically and experimentally. This is partly due to the many complex interconnected mechanical phenomena that occur and partly due to the fact that usual steady-state techniques of analysis cannot be applied. In such complex problems numerical techniques can help to acousticians. To gain some insight into this source of sound, in this paper collision of two steel spheres are studied with finite element method (FEM). Then the FEM results were compared with experiments to show authority of this numerical method to simulate impact noises. FEM results show that if the vibrational modes are excited by impact, the vibrational modes can be as effective as rigid body motion

  11. Multiblock copolymers prepared by patterned modification: Analytical theory and computer simulations

    Science.gov (United States)

    Govorun, E. N.; Gavrilov, A. A.; Chertovich, A. V.

    2015-05-01

    We describe a special type of multiblock copolymers which are synthesized by a hypothetic procedure of the modification of monomer units in a polymer melt according to a certain geometrical criterion. In particular, we explore the case of lamellar-like structures: the sequence statistics of the resulting multiblock copolymers is described and their ability to self-assemble is studied. It is found that the block-size distribution P(k) for such random copolymers contains a large fraction of short blocks with the asymptotic dependence ˜k-3/2, where k is the block size. A characteristic feature of such multiblock copolymers is their extremely high block-size polydispersity with the polydispersity index being proportional to the space period of the modification. The morphological behavior of such copolymers is simulated by means of dissipative particle dynamics. A stable self-assembled lamellar structure is observed, but the domain size appears to be sufficiently larger than the initial pattern period.

  12. Multiblock copolymers prepared by patterned modification: Analytical theory and computer simulations.

    Science.gov (United States)

    Govorun, E N; Gavrilov, A A; Chertovich, A V

    2015-05-28

    We describe a special type of multiblock copolymers which are synthesized by a hypothetic procedure of the modification of monomer units in a polymer melt according to a certain geometrical criterion. In particular, we explore the case of lamellar-like structures: the sequence statistics of the resulting multiblock copolymers is described and their ability to self-assemble is studied. It is found that the block-size distribution P(k) for such random copolymers contains a large fraction of short blocks with the asymptotic dependence ∼k(-3/2), where k is the block size. A characteristic feature of such multiblock copolymers is their extremely high block-size polydispersity with the polydispersity index being proportional to the space period of the modification. The morphological behavior of such copolymers is simulated by means of dissipative particle dynamics. A stable self-assembled lamellar structure is observed, but the domain size appears to be sufficiently larger than the initial pattern period. PMID:26026461

  13. Analytical and Experimental Study of The Effects of Non-Condensable in a Passive Condenser System for The Advanced Boiling Water Reactor

    International Nuclear Information System (INIS)

    The main goal of the project is to study analytically and experimentally condensation heat transfer for the passive condenser system relevant to the safety of next generation nuclear reactor such as Simplified Boiling Water Reactor (BWR). The objectives of this three-year research project are to: (1) obtain experimental data on the phenomenon of condensation of steam in a vertical tube in the presence of non-condensable for flow conditions of PCCS, (2) develop a analytic model for the condensation phenomena in the presence of non-condensable gas for the vertical tube, and (3) assess the RELAP5 computer code against the experimental data. The project involves experiment, theoretical modeling and a thermal-hydraulic code assessment. It involves graduate and undergraduate students' participation providing them with exposure and training in advanced reactor concepts and safety systems

  14. Analytical and Experimental Study of The Effects of Non-Condensable in a Passive Condenser System for The Advanced Boiling Water Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Shripad T. Revankar; Seungmin Oh

    2003-09-30

    The main goal of the project is to study analytically and experimentally condensation heat transfer for the passive condenser system relevant to the safety of next generation nuclear reactor such as Simplified Boiling Water Reactor (BWR). The objectives of this three-year research project are to: (1) obtain experimental data on the phenomenon of condensation of steam in a vertical tube in the presence of non-condensable for flow conditions of PCCS, (2) develop a analytic model for the condensation phenomena in the presence of non-condensable gas for the vertical tube, and (3) assess the RELAP5 computer code against the experimental data. The project involves experiment, theoretical modeling and a thermal-hydraulic code assessment. It involves graduate and undergraduate students' participation providing them with exposure and training in advanced reactor concepts and safety systems

  15. Transition of Monju simulator training owing to Monju accident and upgrade of Monju advanced reactor simulator (MARS)

    International Nuclear Information System (INIS)

    The Monju advanced reactor simulator (MARS) has been operated for training of Monju operators and for verification of Monju operating manual's appropriateness since 1991 for over 11 years. This report covers transition of Monju training system and modified of MARS owing to Monju accident as operating experience of MARS on from 1994 to 2001. The principal points mentioned are as follows: (1) Improved Monju training system owing to Monju accident 1) Reinforcement of sodium handling and sodium fire-fighting exercise. 2) Improved of training system and revised of training frequency. 3) Introduced of evaluation and analysis system regarding training results. 4) Providing of training guide line. 5) Step up of fundamental education by introducing of CAI (Computer Assisted Instruction System). (2) Upgrade of MARS for Monju restarting. 1) Reflected of the real plant data obtained from Monju performance test. 2) Addition of malfunction items. 3) Development of simulation software and addition of simulation panel concerning reinforced sodium leakage corresponding training. 4) Improvement of simulation ability and remodeling of calculating model by renewal of computer system. 5) Up graded program in the future. (author)

  16. Overview of the Consortium for the Advanced Simulation of Light Water Reactors (CASL

    Directory of Open Access Journals (Sweden)

    Kulesza Joel A.

    2016-01-01

    Full Text Available The Consortium for Advanced Simulation of Light Water Reactors (CASL was established in July 2010 for the purpose of providing advanced modeling and simulation solutions for commercial nuclear reactors. The primary goal is to provide coupled, higher-fidelity, usable modeling and simulation capabilities than are currently available. These are needed to address light water reactor (LWR operational and safety performance-defining phenomena that are not yet able to be fully modeled taking a first-principles approach. In order to pursue these goals, CASL has participation from laboratory, academic, and industry partners. These partners are pursuing the solution of ten major “Challenge Problems” in order to advance the state-of-the-art in reactor design and analysis to permit power uprates, higher burnup, life extension, and increased safety. At present, the problems being addressed by CASL are primarily reactor physics-oriented; however, this paper is intended to introduce CASL to the reactor dosimetry community because of the importance of reactor physics modelling and nuclear data to define the source term for that community and the applicability and extensibility of the transport methods being developed.

  17. Overview of the Consortium for the Advanced Simulation of Light Water Reactors (CASL)

    Science.gov (United States)

    Kulesza, Joel A.; Franceschini, Fausto; Evans, Thomas M.; Gehin, Jess C.

    2016-02-01

    The Consortium for Advanced Simulation of Light Water Reactors (CASL) was established in July 2010 for the purpose of providing advanced modeling and simulation solutions for commercial nuclear reactors. The primary goal is to provide coupled, higher-fidelity, usable modeling and simulation capabilities than are currently available. These are needed to address light water reactor (LWR) operational and safety performance-defining phenomena that are not yet able to be fully modeled taking a first-principles approach. In order to pursue these goals, CASL has participation from laboratory, academic, and industry partners. These partners are pursuing the solution of ten major "Challenge Problems" in order to advance the state-of-the-art in reactor design and analysis to permit power uprates, higher burnup, life extension, and increased safety. At present, the problems being addressed by CASL are primarily reactor physics-oriented; however, this paper is intended to introduce CASL to the reactor dosimetry community because of the importance of reactor physics modelling and nuclear data to define the source term for that community and the applicability and extensibility of the transport methods being developed.

  18. 2D fluid-analytical simulation of electromagnetic effects in low pressure, high frequency electronegative capacitive discharges

    Science.gov (United States)

    Kawamura, E.; Lichtenberg, A. J.; Lieberman, M. A.; Marakhtanov, A. M.

    2016-06-01

    A fast 2D axisymmetric fluid-analytical multifrequency capacitively coupled plasma (CCP) reactor code is used to study center high nonuniformity in a low pressure electronegative chlorine discharge. In the code, a time-independent Helmholtz wave equation is used to solve for the capacitive fields in the linearized frequency domain. This eliminates the time dependence from the electromagnetic (EM) solve, greatly speeding up the simulations at the cost of neglecting higher harmonics. However, since the code allows up to three driving frequencies, we can add the two most important harmonics to the CCP simulations as the second and third input frequencies. The amplitude and phase of these harmonics are estimated by using a recently developed 1D radial nonlinear transmission line (TL) model of a highly asymmetric cylindrical discharge (Lieberman et al 2015 Plasma Sources Sci. Technol. 24 055011). We find that at higher applied frequencies, the higher harmonics contribute significantly to the center high nonuniformity due to their shorter plasma wavelengths.

  19. A simulation-based and analytic analysis of the off-Hugoniot response of alternative inertial confinement fusion ablator materials

    Science.gov (United States)

    Moore, Alastair S.; Prisbrey, Shon; Baker, Kevin L.; Celliers, Peter M.; Fry, Jonathan; Dittrich, Thomas R.; Wu, Kuang-Jen J.; Kervin, Margaret L.; Schoff, Michael E.; Farrell, Mike; Nikroo, Abbas; Hurricane, Omar A.

    2016-09-01

    The attainment of self-propagating fusion burn in an inertial confinement target at the National Ignition Facility will require the use of an ablator with high rocket-efficiency and ablation pressure. The ablation material used during the National Ignition Campaign (Lindl et al. 2014) [1], a glow-discharge polymer (GDP), does not couple as efficiently as simulations indicated to the multiple-shock inducing radiation drive environment created by laser power profile (Robey et al., 2012). We investigate the performance of two other ablators, boron carbide (B4C) and high-density carbon (HDC) compared to the performance of GDP under the same hohlraum conditions. Ablation performance is determined through measurement of the shock speed produced in planar samples of the ablator material subjected to the identical multiple-shock inducing radiation drive environments that are similar to a generic three-shock ignition drive. Simulations are in better agreement with the off-Hugoniot performance of B4C than either HDC or GDP, and analytic estimations of the ablation pressure indicate that while the pressure produced by B4C and GDP is similar when the ablator is allowed to release, the pressure reached by B4C seems to exceed that of HDC when backed by a Au/quartz layer.

  20. Planning of development strategy for establishment of advanced simulation of nuclear system

    International Nuclear Information System (INIS)

    In this product, the long term development plan in each technical area has been prosed with the plan of coupled code system. The consolidated code system for safety analysis has been proposing for future needs. The computing hardware needed for te advanced simulation is also proposing. The best approach for future safety analysis simulation capabilities may be a dual-path program. i. e. the development programs for an integrated analysis tool and multi-scale/multi-physic analysis tools, where the former aims at reducing uncertainty and the latter at enhancing accuracy. Integrated analysis tool with risk informed safety margin quantification It requires a significant extension of the phenomenological and geometric capabilities of existing reactor safety analysis software, capable of detailed simulations that reduce the uncertainties. Multi-scale, multi-physics analysis tools. Simplifications of complex phenomenological models and dependencies have been made in current safety analyses to accommodate computer hardware limitations. With the advent of modern computer hardware, these limitations may be removed to permit greater accuracy in representation of physical behavior of materials in design basis and beyond design basis conditions, and hence more accurate assessment of the true safety margins based on first principle methodology. The proposals can be utilized to develop the advanced simulation project and formulation of organization and establishment of high performance computing system in KAERI

  1. High performance pseudo-analytical simulation of multi-object adaptive optics over multi-GPU systems

    KAUST Repository

    Abdelfattah, Ahmad M.

    2014-01-01

    Multi-object adaptive optics (MOAO) is a novel adaptive optics (AO) technique dedicated to the special case of wide-field multi-object spectrographs (MOS). It applies dedicated wavefront corrections to numerous independent tiny patches spread over a large field of view (FOV). The control of each deformable mirror (DM) is done individually using a tomographic reconstruction of the phase based on measurements from a number of wavefront sensors (WFS) pointing at natural and artificial guide stars in the field. The output of this study helps the design of a new instrument called MOSAIC, a multi-object spectrograph proposed for the European Extremely Large Telescope (E-ELT). We have developed a novel hybrid pseudo-analytical simulation scheme that allows us to accurately simulate in detail the tomographic problem. The main challenge resides in the computation of the tomographic reconstructor, which involves pseudo-inversion of a large dense symmetric matrix. The pseudo-inverse is computed using an eigenvalue decomposition, based on the divide and conquer algorithm, on multicore systems with multi-GPUs. Thanks to a new symmetric matrix-vector product (SYMV) multi-GPU kernel, our overall implementation scores significant speedups over standard numerical libraries on multicore, like Intel MKL, and up to 60% speedups over the standard MAGMA implementation on 8 Kepler K20c GPUs. At 40,000 unknowns, this appears to be the largest-scale tomographic AO matrix solver submitted to computation, to date, to our knowledge and opens new research directions for extreme scale AO simulations. © 2014 Springer International Publishing Switzerland.

  2. Simulation research and optimal design for digital power regulating system of China advanced research reactor

    International Nuclear Information System (INIS)

    Based on SimPort simulation platform of nuclear power plant, a simulation model for Digital Power Regulating System (DPRS) of China Advanced Research Reactor (CARR) was established. The transient state of DPRS was simulation studied using this model. According to the characteristics of the driving mechanism of the control rods, the effects of the driving precision of the control rod and its displacement delay upon the system stability were analyzed. Considering the process requirements of CARR and the function characteristic of DRPS, the adjusting parameters for the digital PID controller and the stability limits of the driving mechanism of the control rods were obtained. The sampling period of the digital PID controller is 100 ms and its proportion gain is 300. The stability limit of the driving precision of the control rod is 0.4 mm. The stability limit of displacement delay between electromagnetic coil and armature is 6.0 mm. (authors)

  3. Monte Carlo simulation: tool for the calibration in analytical determination of radionuclides; Simulacion Monte Carlo: herramienta para la calibracion en determinaciones analiticas de radionucleidos

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Jorge A. Carrazana; Ferrera, Eduardo A. Capote; Gomez, Isis M. Fernandez; Castro, Gloria V. Rodriguez; Ricardo, Niury Martinez, E-mail: cphr@cphr.edu.cu [Centro de Proteccion e Higiene de las Radiaciones (CPHR), La Habana (Cuba)

    2013-07-01

    This work shows how is established the traceability of the analytical determinations using this calibration method. Highlights the advantages offered by Monte Carlo simulation for the application of corrections by differences in chemical composition, density and height of the samples analyzed. Likewise, the results obtained by the LVRA in two exercises organized by the International Agency for Atomic Energy (IAEA) are presented. In these exercises (an intercomparison and a proficiency test) all reported analytical results were obtained based on calibrations in efficiency by Monte Carlo simulation using the DETEFF program.

  4. Experimental tests and qualification of analytical methods to address thermohydraulic phenomena in advanced water cooled reactors. Proceedings of a technical committee meeting

    International Nuclear Information System (INIS)

    Worldwide there is considerable experience in nuclear power technology, especially in water cooled reactor technology. Of the operating plants, in September 1998, 346 were light water reactors (LWRs) totalling 306 GW(e) and 29 were heavy water reactors (HWRs) totalling 15 GW(e). The accumulated experience and lessons learned from these plants are being incorporated into new advanced reactor designs. Utility requirements documents have been formulated to guide these design activities by incorporating this experience, and results from research and development programmes, with the aim of reducing costs and licensing uncertainties by establishing the technical bases for the new designs. Common goals for advanced designs are high availability, user-friendly features, competitive economics and compliance with internationally recognized safety objectives. Large water cooled reactors with power outputs of 1300 MW(e) and above, which possess inherent safety characteristics (e.g. negative Doppler moderator temperature coefficients, and negative moderator void coefficient) and incorporate proven, active engineered systems to accomplish safety functions are being developed. Other designs with power outputs from, for example, 220 MW(e) up to about 1300 MW(e) which also possess inherent safety characteristics and which place more emphasis on utilization of passive safety systems are being developed. Passive systems are based on natural forces and phenomena such as natural convection and gravity, making safety functions less dependent on active systems and components like pumps and diesel generators. In some cases, further experimental tests for the thermohydraulic conditions of interest in advanced designs can provide improved understanding of the phenomena. Further, analytical methods to predict reactor thermohydraulic behaviour can be qualified for use by comparison with the experimental results. These activities should ultimately result in more economical designs. The

  5. Benchmarks for interface-tracking codes in the consortium for advanced simulation of LWRs (CASL)

    International Nuclear Information System (INIS)

    A major innovation pursued by the Consortium for Advanced Simulation of LWRs (CASL) is the use of Interface Tracking Methods (ITM) to generate high-fidelity closure relations for two-phase flow and heat transfer phenomena (e.g. nucleate boiling, bubble break-up and coalescence, vapor condensation, etc.), to be used in coarser CFD, subchannel and system codes. ITMs do not assume an idealized geometry of the interface between the liquid and vapor phases, but rather calculate it from ‘first principles’. Also, used within the context of high-fidelity turbulence simulations, such as Direct Numerical Simulation (DNS) or Large Eddy Simulation (LES), ITMs can resolve the velocity (including the fluctuating field) and temperature/scalar gradients near the liquid-vapor interface, so prediction of the exchange of momentum, mass and heat at the interface in principle requires no empirical correlations. The physical complexity of the two-phase flow and heat transfer phenomena encountered in LWRs naturally lends itself to an ITM analysis approach. Several codes featuring ITM capabilities are available within CASL. These are TransAT, STAR-CCM+, PHASTA, FTC3D and FELBM. They use a variety of ITMs ranging from Volume-Of- Fluid to Level-Set, from Front-Tracking to Lattice-Boltzmann. A series of benchmark simulations is being developed to test the key capabilities of these codes and their ITMs. In this paper, three such benchmark simulations, testing DNS, LES and interface tracking, respectively, are briefly described. (author)

  6. Advanced char burnout models for the simulation of pulverized coal fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    T. Severin; S. Wirtz; V. Scherer [Ruhr-University, Bochum (Germany). Institute of Energy Plant Technology (LEAT)

    2005-07-01

    The numerical simulation of coal combustion processes is widely used as an efficient means to predict burner or system behaviour. In this paper an approach to improve CFD simulations of pulverized coal fired boilers with advanced coal combustion models is presented. In simple coal combustion models, first order Arrhenius rate equations are used for devolatilization and char burnout. The accuracy of such simple models is sufficient for the basic aspects of heat release. The prediction of carbon-in-ash is one aspect of special interest in the simulation of pulverized coal fired boilers. To determine the carbon-in-ash levels in the fly ash of coal fired furnaces, the char burnout model has to be more detailed. It was tested, in how far changing operating conditions affect the carbon-in-ash prediction of the simulation. To run several test cases in a short time, a simplified cellnet model was applied. To use a cellnet model for simulations of pulverized coal fired boilers, it was coupled with a Lagrangian particle model, used in CFD simulations, too. 18 refs., 5 figs., 5 tabs.

  7. Mission simulation as an approach to develop requirements for automation in Advanced Life Support Systems

    Science.gov (United States)

    Erickson, J. D.; Eckelkamp, R. E.; Barta, D. J.; Dragg, J.; Henninger, D. L. (Principal Investigator)

    1996-01-01

    This paper examines mission simulation as an approach to develop requirements for automation and robotics for Advanced Life Support Systems (ALSS). The focus is on requirements and applications for command and control, control and monitoring, situation assessment and response, diagnosis and recovery, adaptive planning and scheduling, and other automation applications in addition to mechanized equipment and robotics applications to reduce the excessive human labor requirements to operate and maintain an ALSS. Based on principles of systems engineering, an approach is proposed to assess requirements for automation and robotics using mission simulation tools. First, the story of a simulated mission is defined in terms of processes with attendant types of resources needed, including options for use of automation and robotic systems. Next, systems dynamics models are used in simulation to reveal the implications for selected resource allocation schemes in terms of resources required to complete operational tasks. The simulations not only help establish ALSS design criteria, but also may offer guidance to ALSS research efforts by identifying gaps in knowledge about procedures and/or biophysical processes. Simulations of a planned one-year mission with 4 crewmembers in a Human Rated Test Facility are presented as an approach to evaluation of mission feasibility and definition of automation and robotics requirements.

  8. Advanced computer simulation and modelling for solving single phase hydraulic problems

    International Nuclear Information System (INIS)

    This paper discusses the methods to perform single phase hydraulic calculations for complex piping networks and applications which require a high degree of accuracy. Two separate computer programs are utilized for the simulation and modeling of the networks. Equivalent length of piping and corresponding flows and pressures are calculated by using Overthruster and Kypipe computer programs respectively. The Overthruster Program is designed to perform standardized inplant L/D hydraulic calculations. This program contains certain empirical equations and data. The Kypipe Program is designed specifically to simulate steady state pressure and flow calculations in piping distribution system transporting fluids. Fluor Daniel, completed the modification design and Southern California Edison installed the modification and performed start-up testing of the system. The actual test results, pressures and flows, correlated well within 2 percent of the values predicted by analytical methods. This unique example demonstrates analytical capabilities and the level of accuracies achieved by using this method versus the conventional methods with typical inaccuracies of 10 to 15 percent

  9. Advanced virtual energy simulation training and research: IGCC with CO2 capture power plant

    Energy Technology Data Exchange (ETDEWEB)

    Zitney, S.; Liese, E.; Mahapatra, P.; Bhattacharyya, D.; Provost, G.

    2011-01-01

    In this presentation, we highlight the deployment of a real-time dynamic simulator of an integrated gasification combined cycle (IGCC) power plant with CO{sub 2} capture at the Department of Energy's (DOE) National Energy Technology Laboratory's (NETL) Advanced Virtual Energy Simulation Training and Research (AVESTARTM) Center. The Center was established as part of the DOE's accelerating initiative to advance new clean coal technology for power generation. IGCC systems are an attractive technology option, generating low-cost electricity by converting coal and/or other fuels into a clean synthesis gas mixture in a process that is efficient and environmentally superior to conventional power plants. The IGCC dynamic simulator builds on, and reaches beyond, conventional power plant simulators to merge, for the first time, a 'gasification with CO{sub 2} capture' process simulator with a 'combined-cycle' power simulator. Fueled with coal, petroleum coke, and/or biomass, the gasification island of the simulated IGCC plant consists of two oxygen-blown, downward-fired, entrained-flow, slagging gasifiers with radiant syngas coolers and two-stage sour shift reactors, followed by a dual-stage acid gas removal process for CO{sub 2} capture. The combined cycle island consists of two F-class gas turbines, steam turbine, and a heat recovery steam generator with three-pressure levels. The dynamic simulator can be used for normal base-load operation, as well as plant start-up and shut down. The real-time dynamic simulator also responds satisfactorily to process disturbances, feedstock blending and switchovers, fluctuations in ambient conditions, and power demand load shedding. In addition, the full-scope simulator handles a wide range of abnormal situations, including equipment malfunctions and failures, together with changes initiated through actions from plant field operators. By providing a comprehensive IGCC operator training system, the

  10. Introducing process analytical technology (PAT) in filamentous cultivation process development: comparison of advanced online sensors for biomass measurement

    DEFF Research Database (Denmark)

    Rønnest, Nanna Petersen; Stocks, Stuart M.; Eliasson Lantz, Anna;

    2011-01-01

    cultivation data, such as the carbon dioxide evolution rate (CER) and the concentration of dissolved oxygen. Prediction models for the biomass concentrations were estimated on the basis of the individual sensors and on combinations of the sensors. The results showed that the more advanced sensors based on MWF...

  11. Advances in data analytic methods for evaluating treatment outcome and mechanisms of change: introduction to the special issue

    NARCIS (Netherlands)

    Compton, S.N.; Rosenfield, D.; Hofmann, S.G.; Smits, J.A.J.

    2014-01-01

    This series of articles, which provide an overview of several advanced statistical methods for evaluating treatment outcomes and mechanisms of change, makes up the first research methods–oriented special issue to appear in the Journal of Consulting and Clinical Psychology. Like most active areas of

  12. The importance of simulation facilities for the development of review criteria for advanced human system interfaces

    International Nuclear Information System (INIS)

    Advanced control room (ACR) concepts are being developed in the commercial nuclear industry as part of future reactor designs. The ACRs will use advanced human-system interface (HSI) technologies that may have significant implications for plant safety in that they will affect the operator's overall role (function) in the system, the method of information presentation, the ways in which the operator interacts with the system, and the requirements on the operator to understand and supervise an increasingly complex system. The U.S. Nuclear Regulatory Commission (NRC) reviews the HSI aspects of control rooms to ensure that they are designed to good human factors engineering principles and that operator performance and reliability are appropriately supported to protect public health and safety. The NRC is developing guidelines to support their review of these advanced designs. As part of this effort, a methodology for guidance development was established, and topics in need of further research were identified. Simulators of various kinds are likely to play important roles in the development of review guidelines and in the evaluation of ACRs. This paper describes a general approach to review criteria development, and discusses the role of simulators in addressing research needs

  13. Analysis of PV Advanced Inverter Functions and Setpoints under Time Series Simulation.

    Energy Technology Data Exchange (ETDEWEB)

    Seuss, John [Georgia Inst. of Technology, Atlanta, GA (United States); Reno, Matthew J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Broderick, Robert Joseph [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Grijalva, Santiago [Georgia Inst. of Technology, Atlanta, GA (United States)

    2016-05-01

    Utilities are increasingly concerned about the potential negative impacts distributed PV may have on the operational integrity of their distribution feeders. Some have proposed novel methods for controlling a PV system's grid - tie inverter to mitigate poten tial PV - induced problems. This report investigates the effectiveness of several of these PV advanced inverter controls on improving distribution feeder operational metrics. The controls are simulated on a large PV system interconnected at several locations within two realistic distribution feeder models. Due to the time - domain nature of the advanced inverter controls, quasi - static time series simulations are performed under one week of representative variable irradiance and load data for each feeder. A para metric study is performed on each control type to determine how well certain measurable network metrics improve as a function of the control parameters. This methodology is used to determine appropriate advanced inverter settings for each location on the f eeder and overall for any interconnection location on the feeder.

  14. Improving advanced cardiovascular life support skills in medical students: simulation-based education approach

    Directory of Open Access Journals (Sweden)

    Hamidreza Reihani

    2015-01-01

    Full Text Available Objective: In this trial, we intend to assess the effect of simulation-based education approach on advanced cardiovascular life support skills among medical students. Methods: Through convenient sampling method, 40 interns of Mashhad University of Medical Sciences in their emergency medicine rotation (from September to December 2012 participated in this study. Advanced Cardiovascular Life Support (ACLS workshops with pretest and post-test exams were performed. Workshops and checklists for pretest and post-test exams were designed according to the latest American Heart Association (AHA guidelines. Results: The total score of the students increased significantly after workshops (24.6 out of 100 to 78.6 out of 100. This demonstrates 53.9% improvement in the skills after the simulation-based education (P< 0.001. Also the mean score of each station had a significant improvement (P< 0.001. Conclusion: Pretests showed that interns had poor performance in practical clinical matters while their scientific knowledge, such as ECG interpretation was acceptable. The overall results of the study highlights that Simulation based-education approach is highly effective in Improving ACLS skills among medical students.

  15. Development of an advanced thermal hydraulics model for nuclear power plant simulation

    International Nuclear Information System (INIS)

    This paper summarizes the development of an advanced digital computer thermal hydraulics model for nuclear power plant simulation. A review of thermal hydraulics code design options is presented together with a review of existing engineering models. CAE has developed an unequal temperatures-unequal velocities five equation model based on the drift flux formalism. CAE has selected the model on the basis that phase separation and thermal non-equilibrium are required to simulate complex and important phenomena occurring in systems such as reactor cooling systems (RCS) and steam generators (SG). The drift flux approach to phase separation and countercurrent flow was selected because extensive testing and validation data supports full-range drift flux parameters correlations. The five equation model was also chosen because it conserves important quantities, i.e. mass and energy of each phase, and because of numerical advantages provided by the case of coupling phasic mass conservation equations with phasic energy conservation equations. The basis of CAE's model as well as supporting models for convection and conduction heat transfer, break flow, interphase mass and heat transfer are described. Comparison of code calculations with experimental measurements taken during a small break LOCA test with the OTIS facility are presented. The use of such advanced thermal hydraulics model as plant analyzer considerably improves simulation capabilities of severe transient as well as of normal operation of two phase systems in nuclear power plants. (orig./HP)

  16. Simulation for Supporting Scale-Up of a Fluidized Bed Reactor for Advanced Water Oxidation

    Directory of Open Access Journals (Sweden)

    Farhana Tisa

    2014-01-01

    Full Text Available Simulation of fluidized bed reactor (FBR was accomplished for treating wastewater using Fenton reaction, which is an advanced oxidation process (AOP. The simulation was performed to determine characteristics of FBR performance, concentration profile of the contaminants, and various prominent hydrodynamic properties (e.g., Reynolds number, velocity, and pressure in the reactor. Simulation was implemented for 2.8 L working volume using hydrodynamic correlations, continuous equation, and simplified kinetic information for phenols degradation as a model. The simulation shows that, by using Fe3+ and Fe2+ mixtures as catalyst, TOC degradation up to 45% was achieved for contaminant range of 40–90 mg/L within 60 min. The concentration profiles and hydrodynamic characteristics were also generated. A subsequent scale-up study was also conducted using similitude method. The analysis shows that up to 10 L working volume, the models developed are applicable. The study proves that, using appropriate modeling and simulation, data can be predicted for designing and operating FBR for wastewater treatment.

  17. Simulation for supporting scale-up of a fluidized bed reactor for advanced water oxidation.

    Science.gov (United States)

    Tisa, Farhana; Raman, Abdul Aziz Abdul; Daud, Wan Mohd Ashri Wan

    2014-01-01

    Simulation of fluidized bed reactor (FBR) was accomplished for treating wastewater using Fenton reaction, which is an advanced oxidation process (AOP). The simulation was performed to determine characteristics of FBR performance, concentration profile of the contaminants, and various prominent hydrodynamic properties (e.g., Reynolds number, velocity, and pressure) in the reactor. Simulation was implemented for 2.8 L working volume using hydrodynamic correlations, continuous equation, and simplified kinetic information for phenols degradation as a model. The simulation shows that, by using Fe(3+) and Fe(2+) mixtures as catalyst, TOC degradation up to 45% was achieved for contaminant range of 40-90 mg/L within 60 min. The concentration profiles and hydrodynamic characteristics were also generated. A subsequent scale-up study was also conducted using similitude method. The analysis shows that up to 10 L working volume, the models developed are applicable. The study proves that, using appropriate modeling and simulation, data can be predicted for designing and operating FBR for wastewater treatment. PMID:25309949

  18. Experimental study and advanced CFD simulation of fire safety performance of building external wall insulation system

    Directory of Open Access Journals (Sweden)

    Yan Zhenghua

    2013-11-01

    Full Text Available Large scale fire tests of building external wall insulation system were conducted. In the experiment, thermal-couples were mounted to measure the insulation system surface temperature and the gas temperature inside rooms at the second and third floors. Photos were also taken during the fire tests. The measurement provides information of the ignition and fire spread of the external insulation system which consists of surface protection layer, glass fibre net, bonding thin layer, anchor and the load bearing wall. Comprehensive simulations of the fire tests were carried out using an advanced CFD fire simulation software Simtec (Simulation of Thermal Engineering Complex [1, 2], which is now released by Simtec Soft Sweden, with the turbulent flow, turbulent combustion, thermal radiation, soot formation, convective heat transfer, the fully coupled three dimensional heat transfer inside solid materials, the ‘burn-out' of the surface protection layer and the pyrolysis of the insulation layer, etc, all computed. The simulation is compared with experimental measurement for validation. The simulation well captured the burning and fire spread of the external insulation wall.

  19. Simulation study of detached plasmas by using advanced particle model and fluid model

    International Nuclear Information System (INIS)

    Fluid simulations and particle simulations are performed to understand the physics of detached plasmas in the tokamak divertor. Two dimensional fluid simulations show that detached divertor plasmas are formed for the high density operation in the W-shaped divertor configuration of JT-60U tokamak. Charge-exchange and recombination processes play important roles to cause the detachment. The asymmetry of inner-and-outer divertor plasmas is studied based on a fluid model, and the bifurcated nature of the asymmetry caused by the SOL current is found. Advanced particle simulations demonstrate that the ExB drift by the radial electric field in a SOL plasma causes the asymmetry of flow pattern and density profile. A detached plasma is formed in the divertor region from which the drift flows out, when the ratio of the ExB drift speed to the sound speed exceeds a threshold. Effects of the radial gradient including diamagnetic drift flow on SOL and divertor plasmas are also studied with the two-dimensional particle simulation. (author)

  20. The Nuclear Energy Advanced Modeling and Simulation Enabling Computational Technologies FY09 Report

    Energy Technology Data Exchange (ETDEWEB)

    Diachin, L F; Garaizar, F X; Henson, V E; Pope, G

    2009-10-12

    In this document we report on the status of the Nuclear Energy Advanced Modeling and Simulation (NEAMS) Enabling Computational Technologies (ECT) effort. In particular, we provide the context for ECT In the broader NEAMS program and describe the three pillars of the ECT effort, namely, (1) tools and libraries, (2) software quality assurance, and (3) computational facility (computers, storage, etc) needs. We report on our FY09 deliverables to determine the needs of the integrated performance and safety codes (IPSCs) in these three areas and lay out the general plan for software quality assurance to meet the requirements of DOE and the DOE Advanced Fuel Cycle Initiative (AFCI). We conclude with a brief description of our interactions with the Idaho National Laboratory computer center to determine what is needed to expand their role as a NEAMS user facility.

  1. Development of Computational Approaches for Simulation and Advanced Controls for Hybrid Combustion-Gasification Chemical Looping

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Abhinaya; Lou, Xinsheng; Neuschaefer, Carl; Chaudry, Majid; Quinn, Joseph

    2012-07-31

    This document provides the results of the project through September 2009. The Phase I project has recently been extended from September 2009 to March 2011. The project extension will begin work on Chemical Looping (CL) Prototype modeling and advanced control design exploration in preparation for a scale-up phase. The results to date include: successful development of dual loop chemical looping process models and dynamic simulation software tools, development and test of several advanced control concepts and applications for Chemical Looping transport control and investigation of several sensor concepts and establishment of two feasible sensor candidates recommended for further prototype development and controls integration. There are three sections in this summary and conclusions. Section 1 presents the project scope and objectives. Section 2 highlights the detailed accomplishments by project task area. Section 3 provides conclusions to date and recommendations for future work.

  2. Preliminary results of experimental and analytical investigations of the tumbling phenomenon for an advanced configuration. [X-29 research aircraft

    Science.gov (United States)

    Whipple, R. D.; Croom, M. A.; Fears, S. P.

    1984-01-01

    A sustained autorotative pitching motion usually called 'tumbling' has been observed during dynamic model tests of the X-29A configuration. The X-29 is an advanced design incorporating forward-swept wings and canards in a highly relaxed static stability condition. Beginning with a historical review of the tumbling phenomenon, this paper discusses the current experimental results of dynamic model tumbling tests of the X-29 and the initial efforts to establish an aerodynamic and mathematical model for analysis.

  3. A study on the multicolour evolution of Red Sequence galaxy populations: insights from hydrodynamical simulations and semi-analytical models

    CERN Document Server

    Romeo, A D; Contini, E; Sommer-Larsen, J; Fassbender, R; Napolitano, N R; Antonuccio-Delogu, V; Gavignaud, I

    2015-01-01

    By means of our own cosmological-hydrodynamical simulation and semi-analytical model we studied galaxy population properties in clusters and groups, spanning over 10 different bands from UV to NIR, and their evolution since redshift z=2. We compare our results in terms of galaxy red/blue fractions and luminous-to-faint ratio (LFR) on the Red Sequence (RS) with recent observational data reaching beyond z=1.5. Different selection criteria were tested in order to retrieve galaxies belonging to the RS: either by their quiescence degree measured from their specific SFR ("Dead Sequence"), or by their position in a colour-colour plane which is also a function of sSFR. In both cases, the colour cut and the limiting magnitude threshold were let evolving with redshift, in order to follow the natural shift of the characteristic luminosity in the LF. We find that the Butcher-Oemler effect is wavelength-dependent, with the fraction of blue galaxies increasing steeper in optical colours than in NIR. Besides, only when appl...

  4. 3D simulation of accelerator conventional magnets with end pole defined by an analytical approach controlling multipoles and magnetic length

    CERN Document Server

    Delferrière, O; Duperrier, R

    2000-01-01

    During the design of a magnet, people generally pay particular attention to get the largest transverse section with small contribution of undesirable multipoles, and the 2D cross-section is adjusted in that way with a good accuracy. But the poles are often cut with sharp ends in the beam direction. Otherwise, in order to minimize the stray field to avoid interaction with other elements on the beam lines and corner saturation, it is common to define a simple 45 degrees chamber. The such truncated poles will create an amount of multipoles that could exceed the magnet required tolerances. The magnetic length is also affected by the way that the truncation is done. We propose in this paper a handy analytical model that allows both to control integrated focusing forces and magnetic lengths for each type of conventional magnets (dipole, quadrupole, sextupole). The different end pole profiles are simulated with the 3D-program TOSCA for the dipole and the quadrupole cases. To estimate a possible damaging of optical q...

  5. Collapsed cone convolution and analytical anisotropic algorithm dose calculations compared to VMC++ Monte Carlo simulations in clinical cases

    International Nuclear Information System (INIS)

    The purpose of this work was to study and quantify the differences in dose distributions computed with some of the newest dose calculation algorithms available in commercial planning systems. The study was done for clinical cases originally calculated with pencil beam convolution (PBC) where large density inhomogeneities were present. Three other dose algorithms were used: a pencil beam like algorithm, the anisotropic analytic algorithm (AAA), a convolution superposition algorithm, collapsed cone convolution (CCC), and a Monte Carlo program, voxel Monte Carlo (VMC++). The dose calculation algorithms were compared under static field irradiations at 6 MV and 15 MV using multileaf collimators and hard wedges where necessary. Five clinical cases were studied: three lung and two breast cases. We found that, in terms of accuracy, the CCC algorithm performed better overall than AAA compared to VMC++, but AAA remains an attractive option for routine use in the clinic due to its short computation times. Dose differences between the different algorithms and VMC++ for the median value of the planning target volume (PTV) were typically 0.4% (range: 0.0 to 1.4%) in the lung and -1.3% (range: -2.1 to -0.6%) in the breast for the few cases we analysed. As expected, PTV coverage and dose homogeneity turned out to be more critical in the lung than in the breast cases with respect to the accuracy of the dose calculation. This was observed in the dose volume histograms obtained from the Monte Carlo simulations

  6. Collapsed cone and analytical anisotropic algorithm dose calculations compared to VMC++ Monte Carlo simulations in clinical cases

    International Nuclear Information System (INIS)

    The purpose of this work was to study and quantify the differences in dose distributions computed with some of the newest dose calculation algorithms available in commercial planning systems. The study was done for clinical cases where large density inhomogeneities were present. Three dose algorithms were used: a pencil beam like algorithm, the anisotropic analytic algorithm (AAA), a convolution superposition algorithm, collapsed cone convolution (CCC) and a Monte Carlo program, voxel Monte Carlo (VMC++). The dose calculation algorithms were compared under static field irradiations at 6 MV and 15 MV using multileaf collimators and hard wedges where necessary. Five clinical cases were studied: three lung and two breast cases. We found that the CCC algorithm performed overall better than AAA compared to VMC++, but AAA remains an attractive option for routine use in the clinic due to its short computation times. Dose differences between the different algorithms for the median value of the planning target volume (PTV) were typically 0.4% (range: 0.0-1.4%) in the lung and -1.3% (range: -2.1--0.6%) in the breast for the few cases we analysed. As expected, PTV coverage and dose homogeneity turned out to be more critical in the lung than in the breast cases with respect to the accuracy of the dose calculation. This was observed in the dose volume histograms obtained from the Monte Carlo simulations

  7. Simulations of Failure via Three-Dimensional Cracking in Fuel Cladding for Advanced Nuclear Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Hongbing [Univ. of Texas, Austin, TX (United States); Bukkapatnam, Satish; Harimkar, Sandip; Singh, Raman; Bardenhagen, Scott

    2014-01-09

    Enhancing performance of fuel cladding and duct alloys is a key means of increasing fuel burnup. This project will address the failure of fuel cladding via three-dimensional cracking models. Researchers will develop a simulation code for the failure of the fuel cladding and validate the code through experiments. The objective is to develop an algorithm to determine the failure of fuel cladding in the form of three-dimensional cracking due to prolonged exposure under varying conditions of pressure, temperature, chemical environment, and irradiation. This project encompasses the following tasks: 1. Simulate 3D crack initiation and growth under instantaneous and/or fatigue loads using a new variant of the material point method (MPM); 2. Simulate debonding of the materials in the crack path using cohesive elements, considering normal and shear traction separation laws; 3. Determine the crack propagation path, considering damage of the materials incorporated in the cohesive elements to allow the energy release rate to be minimized; 4. Simulate the three-dimensional fatigue crack growth as a function of loading histories; 5. Verify the simulation code by comparing results to theoretical and numerical studies available in the literature; 6. Conduct experiments to observe the crack path and surface profile in unused fuel cladding and validate against simulation results; and 7. Expand the adaptive mesh refinement infrastructure parallel processing environment to allow adaptive mesh refinement at the 3D crack fronts and adaptive mesh merging in the wake of cracks. Fuel cladding is made of materials such as stainless steels and ferritic steels with added alloying elements, which increase stability and durability under irradiation. As fuel cladding is subjected to water, chemicals, fission gas, pressure, high temperatures, and irradiation while in service, understanding performance is essential. In the fast fuel used in advanced burner reactors, simulations of the nuclear

  8. Simulations of Failure via Three-Dimensional Cracking in Fuel Cladding for Advanced Nuclear Fuels

    International Nuclear Information System (INIS)

    Enhancing performance of fuel cladding and duct alloys is a key means of increasing fuel burnup. This project will address the failure of fuel cladding via three-dimensional cracking models. Researchers will develop a simulation code for the failure of the fuel cladding and validate the code through experiments. The objective is to develop an algorithm to determine the failure of fuel cladding in the form of three-dimensional cracking due to prolonged exposure under varying conditions of pressure, temperature, chemical environment, and irradiation. This project encompasses the following tasks: 1. Simulate 3D crack initiation and growth under instantaneous and/or fatigue loads using a new variant of the material point method (MPM); 2. Simulate debonding of the materials in the crack path using cohesive elements, considering normal and shear traction separation laws; 3. Determine the crack propagation path, considering damage of the materials incorporated in the cohesive elements to allow the energy release rate to be minimized; 4. Simulate the three-dimensional fatigue crack growth as a function of loading histories; 5. Verify the simulation code by comparing results to theoretical and numerical studies available in the literature; 6. Conduct experiments to observe the crack path and surface profile in unused fuel cladding and validate against simulation results; and 7. Expand the adaptive mesh refinement infrastructure parallel processing environment to allow adaptive mesh refinement at the 3D crack fronts and adaptive mesh merging in the wake of cracks. Fuel cladding is made of materials such as stainless steels and ferritic steels with added alloying elements, which increase stability and durability under irradiation. As fuel cladding is subjected to water, chemicals, fission gas, pressure, high temperatures, and irradiation while in service, understanding performance is essential. In the fast fuel used in advanced burner reactors, simulations of the nuclear

  9. Simulation Research on Neutron Guide System CNGC for China Advanced Research Reactor

    Institute of Scientific and Technical Information of China (English)

    WEI; Guo-hai; HAN; Song-bai; HE; Lin-feng; WANG; Yu; WANG; Hong-li; LIU; Yun-tao; CHEN; Dong-feng; ZHAO; Zhi-xiang

    2012-01-01

    <正>The out-pile section of the neutron guide CNGC at CARR (China Advanced Research Reactor) was designed by Monte Carlo simulation with VITESS. The out-pile section of CNGC will be spitted to CNGC-S and CNGC-N, the cold neutron imaging facility and small angle neutron scattering facility will be installed at the end of guides respectively. XRD patterns of Bi1-xLaxFe1-yScyO3 were shown in Fig. 1.

  10. Advanced modeling and simulation of integrated gasification combined cycle power plants with CO2-capture

    International Nuclear Information System (INIS)

    The objective of this thesis is to provide an extensive description of the correlations in some of the most crucial sub-processes for hard coal fired IGCC with carbon capture (CC-IGCC). For this purpose, process simulation models are developed for four industrial gasification processes, the CO-shift cycle, the acid gas removal unit, the sulfur recovery process, the gas turbine, the water-/steam cycle and the air separation unit (ASU). Process simulations clarify the influence of certain boundary conditions on plant operation, performance and economics. Based on that, a comparative benchmark of CC-IGCC concepts is conducted. Furthermore, the influence of integration between the gas turbine and the ASU is analyzed in detail. The generated findings are used to develop an advanced plant configuration with improved economics. Nevertheless, IGCC power plants with carbon capture are not found to be an economically efficient power generation technology at present day boundary conditions.

  11. 3rd International Workshop on Advances in Simulation-Driven Optimization and Modeling

    CERN Document Server

    Leifsson, Leifur; Yang, Xin-She

    2016-01-01

    This edited volume is devoted to the now-ubiquitous use of computational models across most disciplines of engineering and science, led by a trio of world-renowned researchers in the field. Focused on recent advances of modeling and optimization techniques aimed at handling computationally-expensive engineering problems involving simulation models, this book will be an invaluable resource for specialists (engineers, researchers, graduate students) working in areas as diverse as electrical engineering, mechanical and structural engineering, civil engineering, industrial engineering, hydrodynamics, aerospace engineering, microwave and antenna engineering, ocean science and climate modeling, and the automotive industry, where design processes are heavily based on CPU-heavy computer simulations. Various techniques, such as knowledge-based optimization, adjoint sensitivity techniques, and fast replacement models (to name just a few) are explored in-depth along with an array of the latest techniques to optimize the...

  12. Motion-base simulator results of advanced supersonic transport handling qualities with active controls

    Science.gov (United States)

    Feather, J. B.; Joshi, D. S.

    1981-01-01

    Handling qualities of the unaugmented advanced supersonic transport (AST) are deficient in the low-speed, landing approach regime. Consequently, improvement in handling with active control augmentation systems has been achieved using implicit model-following techniques. Extensive fixed-based simulator evaluations were used to validate these systems prior to tests with full motion and visual capabilities on a six-axis motion-base simulator (MBS). These tests compared the handling qualities of the unaugmented AST with several augmented configurations to ascertain the effectiveness of these systems. Cooper-Harper ratings, tracking errors, and control activity data from the MBS tests have been analyzed statistically. The results show the fully augmented AST handling qualities have been improved to an acceptable level.

  13. Neural network setpoint control of an advanced test reactor experiment loop simulation

    Energy Technology Data Exchange (ETDEWEB)

    Cordes, G.A.; Bryan, S.R.; Powell, R.H.; Chick, D.R.

    1990-09-01

    This report describes the design, implementation, and application of artificial neural networks to achieve temperature and flow rate control for a simulation of a typical experiment loop in the Advanced Test Reactor (ATR) located at the Idaho National Engineering Laboratory (INEL). The goal of the project was to research multivariate, nonlinear control using neural networks. A loop simulation code was adapted for the project and used to create a training set and test the neural network controller for comparison with the existing loop controllers. The results for three neural network designs are documented and compared with existing loop controller action. The neural network was shown to be as accurate at loop control as the classical controllers in the operating region represented by the training set. 9 refs., 28 figs., 2 tabs.

  14. Recent advances and perspectives in analytical methodologies for monitoring the bioavailability of trace metals in environmental solid substrates

    DEFF Research Database (Denmark)

    Miró, Manuel; Hansen, Elo Harald

    2006-01-01

    In the last decades, researchers have realised that the impact of trace elements (TE) in environmental solid substrates on ecological systems and biota cannot be ascertained appropriately by means of total metal content measurements. Assessment of TE chemical forms, types of binding and reactivity...... of their associations with particulate forms has, thus, been commonly performed via batch-wise equilibrium-based sequential extraction fractionation methods able to discern TE bound to different soil-phase compartments. In this paper, novel analytical strategies for monitoring the mobility......, bioavailability and the eventual impact of anthropogenic TE in environmental solids are addressed. The potential of passive dosimeters based on microdialysis sampling for on-site, real-time monitoring of chemical contaminants in pore soil solution is thoroughly discussed and critically compared with active...

  15. Advances in analytical spectrochemistry with ionized gases. I. Improved fundamental understanding through laser based techniques. II. Novel bioanalytical applications

    Science.gov (United States)

    Gamez, Gerardo

    Over the past several decades plasma spectrochemistry has become the workhorse for performing elemental analysis. Nevertheless, we are still far from fully understanding the fundamental mechanisms that affect and led to the production of the analytical signal. Thus, the first part of this study was focused on improving our knowledge of plasma fundamental processes. First, the effect of exposing an inductively coupled plasma to a mass spectrometer sampling interface was investigated. Our results show that the mass spectrometer sampler affects the plasma fundamental parameters in a way that changes with gas flow, forward r.f. power, and plasma torch-to-sampler distance. The findings help to better explain the plasma sampling process and have made clear that results from mass-spectrometry based plasma diagnostics are applicable to unperturbed plasmas only as a rough approximation. Second, and instrument was constructed to characterize the fundamental parameters of an analytical glow discharge by using Thomson and Rayleigh laser scattering. A continuous dc glow discharge source was studied and a set of corresponding numerical modeling experiments were performed. The resulting theory agrees qualitatively with the experimental findings; moreover, the theoretical and experimental techniques often provide complementary information. Finally, a temporally and spatially resolved map of the fundamental parameters of a dc glow discharge operated in pulsed mode was obtained. The results confirm previously proposed electron energy-transfer mechanisms at the beginning of the pulse. In contrast, the findings call into question other mechanisms involving plasma gas metastable formation proposed for the time period immediately after the end of the pulse. In the second part of the study an imaging radio frequency glow discharge instrument was developed to provide three-dimensional elemental analysis of solids. The newly developed instrument was then applied to the simultaneous

  16. Strategic Plan for Nuclear Energy -- Knowledge Base for Advanced Modeling and Simulation (NE-KAMS)

    Energy Technology Data Exchange (ETDEWEB)

    Kimberlyn C. Mousseau

    2011-10-01

    The Nuclear Energy Computational Fluid Dynamics Advanced Modeling and Simulation (NE-CAMS) system is being developed at the Idaho National Laboratory (INL) in collaboration with Bettis Laboratory, Sandia National Laboratory (SNL), Argonne National Laboratory (ANL), Utah State University (USU), and other interested parties with the objective of developing and implementing a comprehensive and readily accessible data and information management system for computational fluid dynamics (CFD) verification and validation (V&V) in support of nuclear energy systems design and safety analysis. The two key objectives of the NE-CAMS effort are to identify, collect, assess, store and maintain high resolution and high quality experimental data and related expert knowledge (metadata) for use in CFD V&V assessments specific to the nuclear energy field and to establish a working relationship with the U.S. Nuclear Regulatory Commission (NRC) to develop a CFD V&V database, including benchmark cases, that addresses and supports the associated NRC regulations and policies on the use of CFD analysis. In particular, the NE-CAMS system will support the Department of Energy Office of Nuclear Energy Advanced Modeling and Simulation (NEAMS) Program, which aims to develop and deploy advanced modeling and simulation methods and computational tools for reliable numerical simulation of nuclear reactor systems for design and safety analysis. Primary NE-CAMS Elements There are four primary elements of the NE-CAMS knowledge base designed to support computer modeling and simulation in the nuclear energy arena as listed below. Element 1. The database will contain experimental data that can be used for CFD validation that is relevant to nuclear reactor and plant processes, particularly those important to the nuclear industry and the NRC. Element 2. Qualification standards for data evaluation and classification will be incorporated and applied such that validation data sets will result in well

  17. Current Advances in the Computational Simulation of the Formation of Low-Mass Stars

    Energy Technology Data Exchange (ETDEWEB)

    Klein, R I; Inutsuka, S; Padoan, P; Tomisaka, K

    2005-10-24

    Developing a theory of low-mass star formation ({approx} 0.1 to 3 M{sub {circle_dot}}) remains one of the most elusive and important goals of theoretical astrophysics. The star-formation process is the outcome of the complex dynamics of interstellar gas involving non-linear interactions of turbulence, gravity, magnetic field and radiation. The evolution of protostellar condensations, from the moment they are assembled by turbulent flows to the time they reach stellar densities, spans an enormous range of scales, resulting in a major computational challenge for simulations. Since the previous Protostars and Planets conference, dramatic advances in the development of new numerical algorithmic techniques have been successfully implemented on large scale parallel supercomputers. Among such techniques, Adaptive Mesh Refinement and Smooth Particle Hydrodynamics have provided frameworks to simulate the process of low-mass star formation with a very large dynamic range. It is now feasible to explore the turbulent fragmentation of molecular clouds and the gravitational collapse of cores into stars self-consistently within the same calculation. The increased sophistication of these powerful methods comes with substantial caveats associated with the use of the techniques and the interpretation of the numerical results. In this review, we examine what has been accomplished in the field and present a critique of both numerical methods and scientific results. We stress that computational simulations should obey the available observational constraints and demonstrate numerical convergence. Failing this, results of large scale simulations do not advance our understanding of low-mass star formation.

  18. Design of a neutron activation system around a DD neutron generator by an analytical method and Monte Carlo simulation

    International Nuclear Information System (INIS)

    Recent developments in neutron generator technology suggest that compact instruments with high neutron yield can be used for NAA and PGNAA in combination with high count rate spectrometers. For laboratories far away from Research Reactors (RRs), such devices could serve as an alternative for training students in radioanalytical and nuclear Chemistry and certain specialized applications. As Neutron activation analysis is a well established technique with a long history of documented applications it could be made available to countries where no research reactors or other neutron irradiation facilities exist by using the proposed approach. Prompt gamma neutron activation analysis (PGNAA) is a versatile analytical tool with many applications unique to the technique. As PGNAA is generally performed at RRs external neutron guides with relatively low N flux, the proposed instrument has a potential to supplement existing PGNAA facilities far away from RRs. Neutron generators, particularly the DD-NGs, are a cost effective, easy to operate and particularly safe alternative to other neutron sources, e.g. isotopic neutron sources like Cf-252 or Am/Be. The idea to combine new developments in DD-NG with moderator/shielding and detectors for fast gamma counting emerged from a recent IAEA Coordinated Research Project (CRP) on New Developments in PGNAA, and an IAEA technical meeting on Neutron Generators for Activation Analysis Purposesis currently under preparation. We report on the design and optimization of a Neutron Activation Analysis (NAA) and a Prompt Gamma Neutron Activation Analysis (PGNAA) chamber associated with a D-D neutron generator. The nominal yield of the generator is about 1010 fast neutrons per seconds (E=2.5MeV). MCNP-Monte Carlo N-Particle Transport simulation code and analytical equation, are used to optimize the setup with respect to thermal flux and radiation protection. Many moderators such as Graphite (G), Polyethylene (Poly), Heavy water (HW), Light water

  19. Core library for advanced scenario simulation, C. L. A. S. S.: Principle and application

    International Nuclear Information System (INIS)

    The global warming, the increase of world population and the depletion of fossil resources have lead us in a major energy crisis. Using electronuclear energy could be one of the means to solve a part of these issues. The way out of this crisis may be enlightened by the study of transitional scenarios, guiding the political decisions. The reliability of those studies passes through the wide variety of the simulation tools and the comparison between them. From this perspective and in order to perform complex electronuclear scenario simulation, the open source Core Library for Advance Scenario Simulation (CLASS) is being developed. CLASS main asset is its ability to include any kind of reactor, whether the system is innovative or standard. A reactor is fully described by its evolution database that must contain a set of different fuel compositions in order to simulate transitional scenarios. CLASS aims at being a useful tool to study scenarios involving Generation IV reactors as well as innovative fuel cycles, like the Thorium cycle. The following contribution will present in detail the CLASS software. Starting with the working principle of this tool, one will explain the working process of the different modules such as the evolution module. It will be followed by an exhaustive presentation of the UOX-MOX bases generation procedure. Finally a brief analysis of the error made by the CLASS evolution module will be presented. (author)

  20. Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC).

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Peter Andrew

    2011-12-01

    The objective of the U.S. Department of Energy Office of Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC) is to provide an integrated suite of computational modeling and simulation (M&S) capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive-waste storage facility or disposal repository. Achieving the objective of modeling the performance of a disposal scenario requires describing processes involved in waste form degradation and radionuclide release at the subcontinuum scale, beginning with mechanistic descriptions of chemical reactions and chemical kinetics at the atomic scale, and upscaling into effective, validated constitutive models for input to high-fidelity continuum scale codes for coupled multiphysics simulations of release and transport. Verification and validation (V&V) is required throughout the system to establish evidence-based metrics for the level of confidence in M&S codes and capabilities, including at the subcontiunuum scale and the constitutive models they inform or generate. This Report outlines the nature of the V&V challenge at the subcontinuum scale, an approach to incorporate V&V concepts into subcontinuum scale modeling and simulation (M&S), and a plan to incrementally incorporate effective V&V into subcontinuum scale M&S destined for use in the NEAMS Waste IPSC work flow to meet requirements of quantitative confidence in the constitutive models informed by subcontinuum scale phenomena.

  1. Advanced optical system simulation in a coupled CAD/optical analysis package

    Science.gov (United States)

    Stevenson, Michael A.; Campillo, Chris J.; Jenkins, David G.

    1999-05-01

    Software packages capable of simulating complex optical systems have the power to shorten the design process for non-imaging illumination, projection display, and other imaging illumination systems, Breault Research Organization's Advanced Systems Analysis Program (ASAP) and Robert McNeel and Associates' Rhinoceros computer aided design software, together, allow complicated optical systems to be simulated and analyzed. Through the use of Rhinoceros, an optical system can be accurately modeled in a 3D design environment. ASAP is then used to assign optical properties to the Rhinoceros CAD model. After the optical system has been characterized, it can be analyzed and optimized, by way of features specific to the ASAP optical analysis engine. Using this simulation technique, an HID arc source manufactured by Ushio America, Inc. is accurately represented. 2D CCD images are gathered for the source's emitting-volume across its spectral bandwidth. The images are processed within ASAP, via the inverse Abel command, to produce a 3D emitting-volume. This emitting-volume is combined with an accurate model of the source geometry and its optical properties, to finalize a functioning virtual source model. The characterized source is then joined with a simulated optical system for detailed performance analysis: namely, a projection display system.

  2. Advanced Simulation of Fuel Behavior Under Irradiation in the Pleiades Software Environment

    International Nuclear Information System (INIS)

    A “multi design” new generation software environment called PLEIADES has been developed by the CEA in the framework of a research cooperative program with EDF and AREVA. In this general software environment, ALCYONE is the PWR fuel performance simulation code. It is a multi-dimensional simulation software (1D, 2D and 3D), with applications for normal, transient and accidental conditions. It also has several levels of modelling, from industrial models to mechanistic ones depending on the amount of multi-scale details expected in the results of the simulation. The different dimensional schemes share the same thermomechanical Finite Element Method code CAST3M. The 1D scheme describes the behaviour of the whole rod and gives access to integral values such as rod fission gas release, clad profilometry and elongation. The 3D scheme allows a local study of Pellet Clad Mechanical Interaction (PCMI) by modelling the thermo-mechanical behaviour of one or several pellet fragments and overlying cladding. The 2D scheme is a compromise between calculation time and the accuracy of the local fuel description. Recently the 3D approach has been extended to a short fuel rod model in order to simulate the ballooning phenomenon during accidental transients. In this paper, we will present the general description of the ALCYONE simulation code in the PLEIADES environment (general computation algorithm, advanced fission gas model for UO2 and MOX fuels, 3D computation scheme). A focus will be presented on specific developments which have already been done to simulate accidental conditions such as LOCA and fast transients for different dimensional models. (author)

  3. Analytical model and behavioral simulation approach for a ΣΔ fractional-N synthesizer employing a sample-hold element

    DEFF Research Database (Denmark)

    Cassia, Marco; Shah, Peter Jivan; Bruun, Erik

    2003-01-01

    A previously unknown intrinsic nonlinearity of standard SigmaDelta fractional-N synthesizers is identified. A general analytical model for SigmaDelta fractional-N phased-locked loops (PLLs) that includes the effect of the nonlinearity is derived and an improvement to the synthesizer topology is...... discussed. Also, a new methodology for behavioral simulation is presented: the proposed methodology is based on an object-oriented event-driven approach and offers the possibility to perform very fast and accurate simulations, and the theoretical models developed validate the simulation results. We show a...

  4. Impact of Split Gate in a Novel SOI MOSFET (SPG SOI for Reduction of Short-Channel Effects: Analytical Modeling and Simulation

    Directory of Open Access Journals (Sweden)

    Mohammad K. Anvarifard

    2013-01-01

    Full Text Available In this paper a comprehensive investigation of a novel device called split-gate silicon-on-insulator MOSFET (SPG SOI MOSFET is proposed to reduce short-channel effects (SCEs. Studying the device has been done by analytical approach and simulation. In the proposed structure the gate is split into two parts. A voltage difference exists between the two parts. It is demonstrated that the surface potential in the channel region exhibits a step function. Some improvements are obtained on parameters such as SCEs, hot-carrier effect (HCE, and drain-induced barrier lowering (DIBL. The accuracy of the results obtained by use of the analytical model is verified by ATLAS device simulation software. The obtained results of the model are compared with those of the single-gate (SG SOI MOSFET. The simulation results show that the SPG SOI MOSFET performance is superior.

  5. ARIANNE. Analytical uncertainties. Simulation of influential factors in the inventory of the final web cam; ARIANNE. Incertidumbres analiticas. Factores de simulacion influyentes en el inventario de la isotopia final

    Energy Technology Data Exchange (ETDEWEB)

    Morales Prieto, M.; Ortega Saiz, P.

    2011-07-01

    Analysis of analytical uncertainties of the methodology of simulation of processes for obtaining isotopic ending inventory of spent fuel, the ARIANE experiment explores the part of simulation of burning.

  6. Advanced CFD simulation for the assessment of nuclear safety issues at EDF. Some examples

    International Nuclear Information System (INIS)

    EDF R and D has computer power that puts it amongst the top industrial research centers in the world. Its supercomputers and in-house codes as well as its experts represent important capabilities to support EDF activities (safety analyses, support to the design of new reactors, analysis of accidental situations non reproducible by experiments, better understanding of physics or complex system response, effects of uncertainties and identification of prominent parameters, qualification and optimization of processes and materials...). Advanced numerical simulation is a powerful tool allowing EDF to increase its competitiveness, improve its performance and the safety of its plants. On this issue, EDF made the choice to develop its own in-house codes, instead of using commercial software, in order to be able to capitalize its expertise and methodologies. This choice allowed as well easier technological transfer to the concerned business units or engineering divisions, fast adaptation of our simulation tools to emerging needs and the development of specific physics or functionalities not addressed by the commercial offer. During the last ten years, EDF has decided to open its in-house codes, through the Open Source way. This is the case for Code–Aster (structure analysis), Code–Saturne (computational fluid dynamics, CFD), TELEMAC (flow calculations in aquatic environment), SALOME (generic platform for Pre and Post-Processing) and SYRTHES (heat transfer in complex geometries), among others. The 3 open source software: Code–Aster, Code–Saturne and TELEMAC, are certified by the French Nuclear Regulatory Authority for many «Important to Safety» studies. Advanced simulation, which treats complex, multi-field and multi-physics problems, is of great importance for the assessment of nuclear safety issues. This paper will present 2 examples of advanced simulation using Code–Saturne for safety issues of nuclear power plants in the fields of R and D and engineering: 1

  7. Advanced analytical mass spectrometric techniques and bioassays to characterize untreated and ozonated oil sands process-affected water.

    Science.gov (United States)

    Sun, Nian; Chelme-Ayala, Pamela; Klamerth, Nikolaus; McPhedran, Kerry N; Islam, Md Shahinoor; Perez-Estrada, Leonidas; Drzewicz, Przemysław; Blunt, Brian J; Reichert, Megan; Hagen, Mariel; Tierney, Keith B; Belosevic, Miodrag; Gamal El-Din, Mohamed

    2014-10-01

    Oil sands process-affected water (OSPW) is a toxic and poorly biodegradable mixture of sand, silt, heavy metals, and organics. In this study, qualitative and quantitative comparisons of naphthenic acids (NAs) were done using ultraperformance liquid chromatography time-of-flight mass spectrometry (UPLC TOF-MS), Fourier transform ion cyclotron resonance (FT-ICR) MS, and ion mobility spectrometry (IMS). The unique combination of these analyses allowed for the determination and correlation of NAs, oxidized NAs, and heteroatom (sulfur or nitrogen) NAs. Despite its lower resolution, UPLC-TOF MS was shown to offer a comparable level of reliability and precision as the high resolution FT-ICR MS. Additionally, the impacts of ozonation (35 mg/L utilized ozone dose) and subsequent NAs degradation on OSPW toxicity were assessed via a collection of organisms and toxicity end points using Vibrio fischeri (nonspecific), specific fish macrophage antimicrobial responses, and fish olfactory responses. Fish macrophages exposed to ozonated OSPW for 1 week showed higher production of reactive oxygen and nitrogen intermediates; however, after 12 weeks the responses were reduced significantly. Fish olfactory tests suggested that OSPW interfered with their perception of odorants. Current results indicate that the quantification of NAs species, using novel analytical methods, can be combined with various toxicity methods to assess the efficiency of OSPW treatment processes. PMID:25211339

  8. A Tool for Satellite Communications: Advanced DVB-RCS / DVB-S2 System and Protocol Simulator

    OpenAIRE

    Boussemart, Vincent; Brandt, Hartmut

    2008-01-01

    A tool has been designed to simulate broadband satellite communication systems and techniques: a system and protocol simulator based on advanced DVB-RCS and DVB-S2 standards. As a powerful and flexible tool, it can be used to investigate and optimize current and future satellite communication systems, mainly to develop resource management algorithms and assess system performances. It is capable of simulating a satellite system using Ka-Band with multi-beam European coverage. It integrates rai...

  9. Development and verification of an analytical algorithm to predict absorbed dose distributions in ocular proton therapy using Monte Carlo simulations

    International Nuclear Information System (INIS)

    Proton beam radiotherapy is an effective and non-invasive treatment for uveal melanoma. Recent research efforts have focused on improving the dosimetric accuracy of treatment planning and overcoming the present limitation of relative analytical dose calculations. Monte Carlo algorithms have been shown to accurately predict dose per monitor unit (D/MU) values, but this has yet to be shown for analytical algorithms dedicated to ocular proton therapy, which are typically less computationally expensive than Monte Carlo algorithms. The objective of this study was to determine if an analytical method could predict absolute dose distributions and D/MU values for a variety of treatment fields like those used in ocular proton therapy. To accomplish this objective, we used a previously validated Monte Carlo model of an ocular nozzle to develop an analytical algorithm to predict three-dimensional distributions of D/MU values from pristine Bragg peaks and therapeutically useful spread-out Bragg peaks (SOBPs). Results demonstrated generally good agreement between the analytical and Monte Carlo absolute dose calculations. While agreement in the proximal region decreased for beams with less penetrating Bragg peaks compared with the open-beam condition, the difference was shown to be largely attributable to edge-scattered protons. A method for including this effect in any future analytical algorithm was proposed. Comparisons of D/MU values showed typical agreement to within 0.5%. We conclude that analytical algorithms can be employed to accurately predict absolute proton dose distributions delivered by an ocular nozzle.

  10. Advances in analytical methods and occurrence of organic UV-filters in the environment--A review.

    Science.gov (United States)

    Ramos, Sara; Homem, Vera; Alves, Arminda; Santos, Lúcia

    2015-09-01

    UV-filters are a group of compounds designed mainly to protect skin against UVA and UVB radiation, but they are also included in plastics, furniture, etc., to protect products from light damage. Their massive use in sunscreens for skin protection has been increasing due to the awareness of the chronic and acute effects of UV radiation. Some organic UV-filters have raised significant concerns in the past few years for their continuous usage, persistent input and potential threat to ecological environment and human health. UV-filters end up in wastewater and because wastewater treatment plants are not efficient in removing them, lipophilic compounds tend to sorb onto sludge and hydrophilics end up in river water, contaminating the existing biota. To better understand the risk associated with UV-filters in the environment a thorough review regarding their physicochemical properties, toxicity and environmental degradation, analytical methods and their occurrence was conducted. Higher UV-filter concentrations were found in rivers, reaching 0.3mg/L for the most studied family, the benzophenone derivatives. Concentrations in the ng to μg/L range were also detected for the p-aminobenzoic acid, cinnamate, crylene and benzoyl methane derivatives in lake and sea water. Although at lower levels (few ng/L), UV-filters were also found in tap and groundwater. Swimming pool water is also a sink for UV-filters and its chlorine by-products, at the μg/L range, highlighting the benzophenone and benzimidazole derivatives. Soils and sediments are not frequently studied, but concentrations in the μg/L range have already been found especially for the benzophenone and crylene derivatives. Aquatic biota is frequently studied and UV-filters are found in the ng/g-dw range with higher values for fish and mussels. It has been concluded that more information regarding UV-filter degradation studies both in water and sediments is necessary and environmental occurrences should be monitored more

  11. Advances in analytical methods and occurrence of organic UV-filters in the environment — A review

    International Nuclear Information System (INIS)

    UV-filters are a group of compounds designed mainly to protect skin against UVA and UVB radiation, but they are also included in plastics, furniture, etc., to protect products from light damage. Their massive use in sunscreens for skin protection has been increasing due to the awareness of the chronic and acute effects of UV radiation. Some organic UV-filters have raised significant concerns in the past few years for their continuous usage, persistent input and potential threat to ecological environment and human health. UV-filters end up in wastewater and because wastewater treatment plants are not efficient in removing them, lipophilic compounds tend to sorb onto sludge and hydrophilics end up in river water, contaminating the existing biota. To better understand the risk associated with UV-filters in the environment a thorough review regarding their physicochemical properties, toxicity and environmental degradation, analytical methods and their occurrence was conducted. Higher UV-filter concentrations were found in rivers, reaching 0.3 mg/L for the most studied family, the benzophenone derivatives. Concentrations in the ng to μg/L range were also detected for the p-aminobenzoic acid, cinnamate, crylene and benzoyl methane derivatives in lake and sea water. Although at lower levels (few ng/L), UV-filters were also found in tap and groundwater. Swimming pool water is also a sink for UV-filters and its chlorine by-products, at the μg/L range, highlighting the benzophenone and benzimidazole derivatives. Soils and sediments are not frequently studied, but concentrations in the μg/L range have already been found especially for the benzophenone and crylene derivatives. Aquatic biota is frequently studied and UV-filters are found in the ng/g-dw range with higher values for fish and mussels. It has been concluded that more information regarding UV-filter degradation studies both in water and sediments is necessary and environmental occurrences should be monitored more

  12. Advances in analytical methods and occurrence of organic UV-filters in the environment — A review

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Sara; Homem, Vera, E-mail: vhomem@fe.up.pt; Alves, Arminda; Santos, Lúcia

    2015-09-01

    UV-filters are a group of compounds designed mainly to protect skin against UVA and UVB radiation, but they are also included in plastics, furniture, etc., to protect products from light damage. Their massive use in sunscreens for skin protection has been increasing due to the awareness of the chronic and acute effects of UV radiation. Some organic UV-filters have raised significant concerns in the past few years for their continuous usage, persistent input and potential threat to ecological environment and human health. UV-filters end up in wastewater and because wastewater treatment plants are not efficient in removing them, lipophilic compounds tend to sorb onto sludge and hydrophilics end up in river water, contaminating the existing biota. To better understand the risk associated with UV-filters in the environment a thorough review regarding their physicochemical properties, toxicity and environmental degradation, analytical methods and their occurrence was conducted. Higher UV-filter concentrations were found in rivers, reaching 0.3 mg/L for the most studied family, the benzophenone derivatives. Concentrations in the ng to μg/L range were also detected for the p-aminobenzoic acid, cinnamate, crylene and benzoyl methane derivatives in lake and sea water. Although at lower levels (few ng/L), UV-filters were also found in tap and groundwater. Swimming pool water is also a sink for UV-filters and its chlorine by-products, at the μg/L range, highlighting the benzophenone and benzimidazole derivatives. Soils and sediments are not frequently studied, but concentrations in the μg/L range have already been found especially for the benzophenone and crylene derivatives. Aquatic biota is frequently studied and UV-filters are found in the ng/g-dw range with higher values for fish and mussels. It has been concluded that more information regarding UV-filter degradation studies both in water and sediments is necessary and environmental occurrences should be monitored more

  13. Analytical and experimental evaluation of joining silicon carbide to silicon carbide and silicon nitride to silicon nitride for advanced heat engine applications Phase 2. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Sundberg, G.J.; Vartabedian, A.M.; Wade, J.A.; White, C.S. [Norton Co., Northboro, MA (United States). Advanced Ceramics Div.

    1994-10-01

    The purpose of joining, Phase 2 was to develop joining technologies for HIP`ed Si{sub 3}N{sub 4} with 4wt% Y{sub 2}O{sub 3} (NCX-5101) and for a siliconized SiC (NT230) for various geometries including: butt joins, curved joins and shaft to disk joins. In addition, more extensive mechanical characterization of silicon nitride joins to enhance the predictive capabilities of the analytical/numerical models for structural components in advanced heat engines was provided. Mechanical evaluation were performed by: flexure strength at 22 C and 1,370 C, stress rupture at 1,370 C, high temperature creep, 22 C tensile testing and spin tests. While the silicon nitride joins were produced with sufficient integrity for many applications, the lower join strength would limit its use in the more severe structural applications. Thus, the silicon carbide join quality was deemed unsatisfactory to advance to more complex, curved geometries. The silicon carbide joining methods covered within this contract, although not entirely successful, have emphasized the need to focus future efforts upon ways to obtain a homogeneous, well sintered parent/join interface prior to siliconization. In conclusion, the improved definition of the silicon carbide joining problem obtained by efforts during this contract have provided avenues for future work that could successfully obtain heat engine quality joins.

  14. Analytical and experimental evaluation of joining silicon carbide to silicon carbide and silicon nitride to silicon nitride for advanced heat engine applications, phase 2

    Science.gov (United States)

    Sundberg, G. J.; Vartabedian, A. M.; Wade, J. A.; White, C. S.

    1994-10-01

    The purpose of joining, Phase 2 was to develop joining technologies for HIP'ed Si3N4 with 4wt% Y2O3 (NCX-5101) and for a siliconized SiC (NT230) for various geometries including: butt joins, curved joins and shaft to disk joins. In addition, more extensive mechanical characterization of silicon nitride joins to enhance the predictive capabilities of the analytical/numerical models for structural components in advanced heat engines was provided. Mechanical evaluation were performed by: flexure strength at 22 C and 1,370 C, stress rupture at 1,370 C, high temperature creep, 22 C tensile testing and spin tests. While the silicon nitride joins were produced with sufficient integrity for many applications, the lower join strength would limit its use in the more severe structural applications. Thus, the silicon carbide join quality was deemed unsatisfactory to advance to more complex, curved geometries. The silicon carbide joining methods covered within this contract, although not entirely successful, have emphasized the need to focus future efforts upon ways to obtain a homogeneous, well sintered parent/join interface prior to siliconization. In conclusion, the improved definition of the silicon carbide joining problem obtained by efforts during this contract have provided avenues for future work that could successfully obtain heat engine quality joins.

  15. Advanced Maintenance Simulation by Means of Hand-Based Haptic Interfaces

    Science.gov (United States)

    Nappi, Michele; Paolino, Luca; Ricciardi, Stefano; Sebillo, Monica; Vitiello, Giuliana

    Aerospace industry has been involved in virtual simulation for design and testing since the birth of virtual reality. Today this industry is showing a growing interest in the development of haptic-based maintenance training applications, which represent the most advanced way to simulate maintenance and repair tasks within a virtual environment by means of a visual-haptic approach. The goal is to allow the trainee to experiment the service procedures not only as a workflow reproduced at a visual level but also in terms of the kinaesthetic feedback involved with the manipulation of tools and components. This study, conducted in collaboration with aerospace industry specialists, is aimed to the development of an immersive virtual capable of immerging the trainees into a virtual environment where mechanics and technicians can perform maintenance simulation or training tasks by directly manipulating 3D virtual models of aircraft parts while perceiving force feedback through the haptic interface. The proposed system is based on ViRstperson, a virtual reality engine under development at the Italian Center for Aerospace Research (CIRA) to support engineering and technical activities such as design-time maintenance procedure validation, and maintenance training. This engine has been extended to support haptic-based interaction, enabling a more complete level of interaction, also in terms of impedance control, and thus fostering the development of haptic knowledge in the user. The user’s “sense of touch” within the immersive virtual environment is simulated through an Immersion CyberForce® hand-based force-feedback device. Preliminary testing of the proposed system seems encouraging.

  16. Monte Carlo simulations of the vacuum performance of differential pumps at the Advanced Photon Source

    International Nuclear Information System (INIS)

    Monte Carlo computer simulations have been successfully applied in the design of vacuum systems. These simulations allow the user to check the vacuum performance without the need of making a prototype of the vacuum system. In this paper we demonstrate the effectiveness and aptitude of these simulations in the design of differential pumps for synchrotron radiation beamlines. Eventually a good number of the beamline front ends at the Advanced Photon Source (APS) will use differential pumps to protect the synchrotron storage ring vacuum. A Monte Carlo computer program is used to calculate the molecular flow transmission and pressure distribution across the differential pump. A differential pump system, which consists of two 170 l/s ion pumps with three conductance-limiting apertures, was previously tested on an APS insertion-device beamline front end. Pressure distribution measurements using controlled leaks demonstrated a pressure difference of over two decades across the differential pump. A new differential pump utilizes a fixed mask between two 170 l/s ion pumps. The fixed mask, which has a conical channel with a small cross section of 4.5x4.5 mm2 in the far end, is used in the beamline to confine the photon beam. Monte Carlo simulations indicate that this configuration with the fixed mask significantly improves the pressure reduction capability of the differential pump, to ∼3x10-5, within the operational range from ∼10-4 to 10-10 Torr. The lower end of pressure is limited by outgassing from front-end components and the higher end by the pumping ability of the ion pump. copyright 1996 American Institute of Physics

  17. Strategic Plan for Nuclear Energy -- Knowledge Base for Advanced Modeling and Simulation (NE-KAMS)

    International Nuclear Information System (INIS)

    NE-KAMS knowledge base will assist computational analysts, physics model developers, experimentalists, nuclear reactor designers, and federal regulators by: (1) Establishing accepted standards, requirements and best practices for V and V and UQ of computational models and simulations, (2) Establishing accepted standards and procedures for qualifying and classifying experimental and numerical benchmark data, (3) Providing readily accessible databases for nuclear energy related experimental and numerical benchmark data that can be used in V and V assessments and computational methods development, (4) Providing a searchable knowledge base of information, documents and data on V and V and UQ, and (5) Providing web-enabled applications, tools and utilities for V and V and UQ activities, data assessment and processing, and information and data searches. From its inception, NE-KAMS will directly support nuclear energy research, development and demonstration programs within the U.S. Department of Energy (DOE), including the Consortium for Advanced Simulation of Light Water Reactors (CASL), the Nuclear Energy Advanced Modeling and Simulation (NEAMS), the Light Water Reactor Sustainability (LWRS), the Small Modular Reactors (SMR), and the Next Generation Nuclear Power Plant (NGNP) programs. These programs all involve computational modeling and simulation (M and S) of nuclear reactor systems, components and processes, and it is envisioned that NE-KAMS will help to coordinate and facilitate collaboration and sharing of resources and expertise for V and V and UQ across these programs. In addition, from the outset, NE-KAMS will support the use of computational M and S in the nuclear industry by developing guidelines and recommended practices aimed at quantifying the uncertainty and assessing the applicability of existing analysis models and methods. The NE-KAMS effort will initially focus on supporting the use of computational fluid dynamics (CFD) and thermal hydraulics (T

  18. Strategic Plan for Nuclear Energy -- Knowledge Base for Advanced Modeling and Simulation (NE-KAMS)

    Energy Technology Data Exchange (ETDEWEB)

    Rich Johnson; Kimberlyn C. Mousseau; Hyung Lee

    2011-09-01

    NE-KAMS knowledge base will assist computational analysts, physics model developers, experimentalists, nuclear reactor designers, and federal regulators by: (1) Establishing accepted standards, requirements and best practices for V&V and UQ of computational models and simulations, (2) Establishing accepted standards and procedures for qualifying and classifying experimental and numerical benchmark data, (3) Providing readily accessible databases for nuclear energy related experimental and numerical benchmark data that can be used in V&V assessments and computational methods development, (4) Providing a searchable knowledge base of information, documents and data on V&V and UQ, and (5) Providing web-enabled applications, tools and utilities for V&V and UQ activities, data assessment and processing, and information and data searches. From its inception, NE-KAMS will directly support nuclear energy research, development and demonstration programs within the U.S. Department of Energy (DOE), including the Consortium for Advanced Simulation of Light Water Reactors (CASL), the Nuclear Energy Advanced Modeling and Simulation (NEAMS), the Light Water Reactor Sustainability (LWRS), the Small Modular Reactors (SMR), and the Next Generation Nuclear Power Plant (NGNP) programs. These programs all involve computational modeling and simulation (M&S) of nuclear reactor systems, components and processes, and it is envisioned that NE-KAMS will help to coordinate and facilitate collaboration and sharing of resources and expertise for V&V and UQ across these programs. In addition, from the outset, NE-KAMS will support the use of computational M&S in the nuclear industry by developing guidelines and recommended practices aimed at quantifying the uncertainty and assessing the applicability of existing analysis models and methods. The NE-KAMS effort will initially focus on supporting the use of computational fluid dynamics (CFD) and thermal hydraulics (T/H) analysis for M&S of nuclear

  19. A graphical simulator for teaching basic and advanced MR imaging techniques

    DEFF Research Database (Denmark)

    Hanson, Lars G

    2007-01-01

    for radiologists, radiographers, and technical staff alike, but it is notoriously challenging to explain spin dynamics by using traditional teaching tools. The author developed a freely available graphical simulator based on the Bloch equations to aid in the teaching of topics ranging from precession...... and relaxation to advanced concepts such as stimulated echoes, spin tagging, and k-space-methods. A graphical user interface provides the user with a three-dimensional view of spin isochromates that can be manipulated by selecting radiofrequency pulses and gradient events. Even complicated sequences can...... be visualized in an intuitive way. The cross-platform software is primarily designed for use in lectures, but is also useful for self studies and student assignments. Movies available at http://radiographics.rsnajnls.org/cgi/content/full/e27/DC1 ....

  20. Advanced Simulation and Computing Fiscal Year 2016 Implementation Plan, Version 0

    Energy Technology Data Exchange (ETDEWEB)

    McCoy, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Archer, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hendrickson, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-08-27

    The Stockpile Stewardship Program (SSP) is an integrated technical program for maintaining the safety, surety, and reliability of the U.S. nuclear stockpile. The SSP uses nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of experimental facilities and programs, and the computational capabilities to support these programs. The purpose of this IP is to outline key work requirements to be performed and to control individual work activities within the scope of work. Contractors may not deviate from this plan without a revised WA or subsequent IP.

  1. Advanced adaptive computational methods for Navier-Stokes simulations in rotorcraft aerodynamics

    Science.gov (United States)

    Stowers, S. T.; Bass, J. M.; Oden, J. T.

    1993-01-01

    A phase 2 research and development effort was conducted in area transonic, compressible, inviscid flows with an ultimate goal of numerically modeling complex flows inherent in advanced helicopter blade designs. The algorithms and methodologies therefore are classified as adaptive methods, which are error estimation techniques for approximating the local numerical error, and automatically refine or unrefine the mesh so as to deliver a given level of accuracy. The result is a scheme which attempts to produce the best possible results with the least number of grid points, degrees of freedom, and operations. These types of schemes automatically locate and resolve shocks, shear layers, and other flow details to an accuracy level specified by the user of the code. The phase 1 work involved a feasibility study of h-adaptive methods for steady viscous flows, with emphasis on accurate simulation of vortex initiation, migration, and interaction. Phase 2 effort focused on extending these algorithms and methodologies to a three-dimensional topology.

  2. Virtual charge state separator as an advanced tool coupling measurements and simulations

    Science.gov (United States)

    Yaramyshev, S.; Vormann, H.; Adonin, A.; Barth, W.; Dahl, L.; Gerhard, P.; Groening, L.; Hollinger, R.; Maier, M.; Mickat, S.; Orzhekhovskaya, A.

    2015-05-01

    A new low energy beam transport for a multicharge uranium beam will be built at the GSI High Current Injector (HSI). All uranium charge states coming from the new ion source will be injected into GSI heavy ion high current HSI Radio Frequency Quadrupole (RFQ), but only the design ions U4 + will be accelerated to the final RFQ energy. A detailed knowledge about injected beam current and emittance for pure design U4 + ions is necessary for a proper beam line design commissioning and operation, while measurements are possible only for a full beam including all charge states. Detailed measurements of the beam current and emittance are performed behind the first quadrupole triplet of the beam line. A dedicated algorithm, based on a combination of measurements and the results of advanced beam dynamics simulations, provides for an extraction of beam current and emittance values for only the U4 + component of the beam. The proposed methods and obtained results are presented.

  3. Photocatalytic Removal of Microcystin-LR by Advanced WO3-Based Nanoparticles under Simulated Solar Light

    Directory of Open Access Journals (Sweden)

    Chao Zhao

    2015-01-01

    Full Text Available A series of advanced WO3-based photocatalysts including CuO/WO3, Pd/WO3, and Pt/WO3 were synthesized for the photocatalytic removal of microcystin-LR (MC-LR under simulated solar light. In the present study, Pt/WO3 exhibited the best performance for the photocatalytic degradation of MC-LR. The MC-LR degradation can be described by pseudo-first-order kinetic model. Chloride ion (Cl− with proper concentration could enhance the MC-LR degradation. The presence of metal cations (Cu2+ and Fe3+ improved the photocatalytic degradation of MC-LR. This study suggests that Pt/WO3 photocatalytic oxidation under solar light is a promising option for the purification of water containing MC-LR.

  4. Application of artificial neural network coupled with genetic algorithm and simulated annealing to solve groundwater inflow problem to an advancing open pit mine

    Science.gov (United States)

    Bahrami, Saeed; Doulati Ardejani, Faramarz; Baafi, Ernest

    2016-05-01

    In this study, hybrid models are designed to predict groundwater inflow to an advancing open pit mine and the hydraulic head (HH) in observation wells at different distances from the centre of the pit during its advance. Hybrid methods coupling artificial neural network (ANN) with genetic algorithm (GA) methods (ANN-GA), and simulated annealing (SA) methods (ANN-SA), were utilised. Ratios of depth of pit penetration in aquifer to aquifer thickness, pit bottom radius to its top radius, inverse of pit advance time and the HH in the observation wells to the distance of observation wells from the centre of the pit were used as inputs to the networks. To achieve the objective two hybrid models consisting of ANN-GA and ANN-SA with 4-5-3-1 arrangement were designed. In addition, by switching the last argument of the input layer with the argument of the output layer of two earlier models, two new models were developed to predict the HH in the observation wells for the period of the mining process. The accuracy and reliability of models are verified by field data, results of a numerical finite element model using SEEP/W, outputs of simple ANNs and some well-known analytical solutions. Predicted results obtained by the hybrid methods are closer to the field data compared to the outputs of analytical and simple ANN models. Results show that despite the use of fewer and simpler parameters by the hybrid models, the ANN-GA and to some extent the ANN-SA have the ability to compete with the numerical models.

  5. Advanced Simulation and Computing: A Summary Report to the Director's Review

    Energy Technology Data Exchange (ETDEWEB)

    McCoy, M G; Peck, T

    2003-06-01

    It has now been three years since the Advanced Simulation and Computing Program (ASCI), as managed by Defense and Nuclear Technologies (DNT) Directorate, has been reviewed by this Director's Review Committee (DRC). Since that time, there has been considerable progress for all components of the ASCI Program, and these developments will be highlighted in this document and in the presentations planned for June 9 and 10, 2003. There have also been some name changes. Today, the Program is called ''Advanced Simulation and Computing,'' Although it retains the familiar acronym ASCI, the initiative nature of the effort has given way to sustained services as an integral part of the Stockpile Stewardship Program (SSP). All computing efforts at LLNL and the other two Defense Program (DP) laboratories are funded and managed under ASCI. This includes the so-called legacy codes, which remain essential tools in stockpile stewardship. The contract between the Department of Energy (DOE) and the University of California (UC) specifies an independent appraisal of Directorate technical work and programmatic management. Such represents the work of this DNT Review Committee. Beginning this year, the Laboratory is implementing a new review system. This process was negotiated between UC, the National Nuclear Security Administration (NNSA), and the Laboratory Directors. Central to this approach are eight performance objectives that focus on key programmatic and administrative goals. Associated with each of these objectives are a number of performance measures to more clearly characterize the attainment of the objectives. Each performance measure has a lead directorate and one or more contributing directorates. Each measure has an evaluation plan and has identified expected documentation to be included in the ''Assessment File''.

  6. Numerical Simulation of Polarity Characteristics of Vector Elastic Wave of Advanced Detection in the Roadway

    Directory of Open Access Journals (Sweden)

    Deng Shuaiqi

    2013-05-01

    Full Text Available The high-order staggering grid Finite-Difference (FD scheme based on first-order velocity-stress elastic wave equation has been deduced. The calculation method of PML boundary condition and stability condition established in this study can be used for numerical simulation of advanced detection of elastic wave in roadway, with the obtaining of high-precision seismogram. Then we systematically analyze the polarity of vector wave field in post-source observation system. The results indicate that the relationship between the vector wave field and the polarity of direct wave is related to reflection coefficient on the interface, while the polarity relationship between horizontal and vertical components of vector wave field is related to vertical position of the interface. During data processing for advanced detection of elastic waves, the sign of the reflection coefficient on the interface ahead can be determined based on the polarity relationship between reflected wave and direct wave from the seismograms; the soft and hard rock and other geological information on both sides of the interface is thus be determined. In addition, the direction of source wave depends on polarity relationship between horizontal and vertical components of reflected wave and is used to achieve the separation of up going and down going waves.

  7. Comprehensive support for nuclear decommissioning based on 3D simulation and advanced user interface technologies

    International Nuclear Information System (INIS)

    There is an increasing international focus on the need to optimise decommissioning strategies, driven by the anticipation of high costs and major effort for the decommissioning of nuclear facilities in the coming decades. The goals are to control and mitigate costs and negative impacts on workers, the general public, and the environment. The methods presently employed for many decommissioning tasks do not apply the latest advancements of science and technology. Therefore, there is growing interest in research and development into the adoption of novel techniques for improving safety, reducing costs, and increasing transparency. This paper provides a comprehensive overview of the authors' results from investigating how current and emerging technologies can be applied to enhance the international decommissioning strategy, focussing in particular on three-dimensional simulation, virtual reality, advanced user interfaces, mobile and wearable devices, and geographical information systems. Our results demonstrate that emerging technologies have great potential for supporting adoption of new instrumentation, improving data and knowledge management, optimising project plans, briefing and training field operators, and for communication, surveillance, and education in general. (author)

  8. Advances in direct numerical simulation for MHD modeling of free surface flows

    International Nuclear Information System (INIS)

    The utilization of FLiBe (LiF-BeF2) free-surface flow as a chamber protection scheme is considered in advanced nuclear fusion reactor. At the design of the nuclear fusion reactor from the viewpoint of thermofluid research, it would be very important to understand the influence of a magnetic field in turbulent free surface flow. On the other hand, turbulent free surface flow (called open channel flow) by direct numerical simulation (DNS) with non-deformable surface was first succeeded by imposing free-slip and non-slip conditions as velocity boundary conditions at the upper and lower, respectively. After that, the research by DNS has been advanced more, it has been clarified that turbulent structures generated from the lower wall travels to the free surface and affected the mechanism of heat and mass transfer at the free surface. The behavior of the structures is affected by the strong magnetic field in the nuclear fusion reactor. Therefore, a DNS of liquid film cooling in the nuclear fusion reactor is performed by authors, and the relations between a magnetic orientation and turbulent flow statistics are clearly observed. In this paper, the DNS result is introduced, and the trial turbulence modeling for MHD free-surface flow by using the DNS database is also discussed

  9. Analytical and Experimental Evaluation of Joining Silicon Carbide to Silicon Carbide and Silicon Nitride to Silicon Nitride for Advanced Heat Engine Applications Phase II

    Energy Technology Data Exchange (ETDEWEB)

    Sundberg, G.J.

    1994-01-01

    Techniques were developed to produce reliable silicon nitride to silicon nitride (NCX-5101) curved joins which were used to manufacture spin test specimens as a proof of concept to simulate parts such as a simple rotor. Specimens were machined from the curved joins to measure the following properties of the join interlayer: tensile strength, shear strength, 22 C flexure strength and 1370 C flexure strength. In parallel, extensive silicon nitride tensile creep evaluation of planar butt joins provided a sufficient data base to develop models with accurate predictive capability for different geometries. Analytical models applied satisfactorily to the silicon nitride joins were Norton's Law for creep strain, a modified Norton's Law internal variable model and the Monkman-Grant relationship for failure modeling. The Theta Projection method was less successful. Attempts were also made to develop planar butt joins of siliconized silicon carbide (NT230).

  10. Gamma-gamma density and lithology tools simulation based on GEANT4 advanced low energy Compton scattering (GALECS) package

    International Nuclear Information System (INIS)

    Geophysical bore-hole data represent the physical properties of rocks, such as density and formation lithology, as a function of depth in a well. Properties of rocks are obtained from gamma ray transport logs. Transport of gamma rays, from a 137Cs point gamma source situated in a bore-hole tool, through rock media to detectors, has been simulated using a GEANT4 radiation transport code. The advanced Compton scattering concepts were used to gain better analyses about well formation. The simulation and understanding of advanced Compton scattering highly depends on how accurately the effects of Doppler broadening and Rayleigh scattering are taken into account. A Monte Carlo package that simulates the gamma-gamma well logging tools based on GEANT4 advanced low energy Compton scattering (GALECS).

  11. Numerical simulation and experimental validation of the three-dimensional flow field and relative analyte concentration distribution in an atmospheric pressure ion source.

    Science.gov (United States)

    Poehler, Thorsten; Kunte, Robert; Hoenen, Herwart; Jeschke, Peter; Wissdorf, Walter; Brockmann, Klaus J; Benter, Thorsten

    2011-11-01

    In this study, the validation and analysis of steady state numerical simulations of the gas flows within a multi-purpose ion source (MPIS) are presented. The experimental results were obtained with particle image velocimetry (PIV) measurements in a non-scaled MPIS. Two-dimensional time-averaged velocity and turbulent kinetic energy distributions are presented for two dry gas volume flow rates. The numerical results of the validation simulations are in very good agreement with the experimental data. All significant flow features have been correctly predicted within the accuracy of the experiments. For technical reasons, the experiments were conducted at room temperature. Thus, numerical simulations of ionization conditions at two operating points of the MPIS are also presented. It is clearly shown that the dry gas volume flow rate has the most significant impact on the overall flow pattern within the APLI source; far less critical is the (larger) nebulization gas flow. In addition to the approximate solution of Reynolds-Averaged Navier-Stokes equations, a transport equation for the relative analyte concentration has been solved. The results yield information on the three-dimensional analyte distribution within the source. It becomes evident that for ion transport into the MS ion transfer capillary, electromagnetic forces are at least as important as fluid dynamic forces. However, only the fluid dynamics determines the three-dimensional distribution of analyte gas. Thus, local flow phenomena in close proximity to the spray shield are strongly impacting on the ionization efficiency. PMID:21952755

  12. Fast and Accurate Icepak-PSpice Co-Simulation of IGBTs under Short-Circuit with an Advanced PSpice Model

    DEFF Research Database (Denmark)

    Wu, Rui; Iannuzzo, Francesco; Wang, Huai;

    2014-01-01

    A basic problem in the IGBT short-circuit failure mechanism study is to obtain realistic temperature distribution inside the chip, which demands accurate electrical simulation to obtain power loss distribution as well as detailed IGBT geometry and material information. This paper describes an...... unprecedented fast and accurate approach to electro-thermal simulation of power IGBTs suitable to simulate normal as well as abnormal conditions based on an advanced physics-based PSpice model together with ANSYS/Icepak FEM thermal simulator in a closed loop. Through this approach, significantly faster...... simulation speed with respect to conventional double-physics simulations, together with very accurate results can be achieved. A case study is given which presents the detailed electrical and thermal simulation results of an IGBT module under short circuit conditions. Furthermore, thermal maps in the case of...

  13. Technology advancement for the ASCENDS mission using the ASCENDS CarbonHawk Experiment Simulator (ACES)

    Science.gov (United States)

    Obland, M. D.; Antill, C.; Browell, E. V.; Campbell, J. F.; CHEN, S.; Cleckner, C.; Dijoseph, M. S.; Harrison, F. W.; Ismail, S.; Lin, B.; Meadows, B. L.; Mills, C.; Nehrir, A. R.; Notari, A.; Prasad, N. S.; Kooi, S. A.; Vitullo, N.; Dobler, J. T.; Bender, J.; Blume, N.; Braun, M.; Horney, S.; McGregor, D.; Neal, M.; Shure, M.; Zaccheo, T.; Moore, B.; Crowell, S.; Rayner, P. J.; Welch, W.

    2013-12-01

    The ASCENDS CarbonHawk Experiment Simulator (ACES) is a NASA Langley Research Center project funded by NASA's Earth Science Technology Office that seeks to advance technologies critical to measuring atmospheric column carbon dioxide (CO2) mixing ratios in support of the NASA Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) mission. The technologies being advanced are: (1) multiple transmitter and telescope-aperture operations, (2) high-efficiency CO2 laser transmitters, (3) a high bandwidth detector and transimpedance amplifier (TIA), and (4) advanced algorithms for cloud and aerosol discrimination. The instrument architecture is being developed for ACES to operate on a high-altitude aircraft, and it will be directly scalable to meet the ASCENDS mission requirements. The above technologies are critical for developing an airborne simulator and spaceborne instrument with lower platform consumption of size, mass, and power, and with improved performance. This design employs several laser transmitters and telescope-apertures to demonstrate column CO2 retrievals with alignment of multiple laser beams in the far-field. ACES will transmit five laser beams: three from commercial lasers operating near 1.57-microns, and two from the Exelis atmospheric oxygen (O2) fiber laser amplifier system operating near 1.26-microns. The Master Oscillator Power Amplifier at 1.57-microns measures CO2 column concentrations using an Integrated-Path Differential Absorption (IPDA) lidar approach. O2 column amounts needed for calculating the CO2 mixing ratio will be retrieved using the Exelis laser system with a similar IPDA approach. The three aperture telescope design was built to meet the constraints of the Global Hawk high-altitude unmanned aerial vehicle (UAV). This assembly integrates fiber-coupled transmit collimators for all of the laser transmitters and fiber-coupled optical signals from the three telescopes to the aft optics and detector package. The detector

  14. Propulsion Simulations Using Advanced Turbulence Models with the Unstructured Grid CFD Tool, TetrUSS

    Science.gov (United States)

    Abdol-Hamid, Khaled S.; Frink, Neal T.; Deere, Karen A.; Pandya, Mohangna J.

    2004-01-01

    A computational investigation has been completed to assess the capability of TetrUSS for exhaust nozzle flows. Three configurations were chosen for this study (1) an axisymmetric supersonic jet, (2) a transonic axisymmetric boattail with solid sting operated at different Reynolds number and Mach number, and (3) an isolated non-axisymmetric nacelle with a supersonic cruise nozzle. These configurations were chosen because existing experimental data provided a means for measuring the ability of TetrUSS for simulating complex nozzle flows. The main objective of this paper is to validate the implementation of advanced two-equation turbulence models in the unstructured-grid CFD code USM3D for propulsion flow cases. USM3D is the flow solver of the TetrUSS system. Three different turbulence models, namely, Menter Shear Stress Transport (SST), basic k epsilon, and the Spalart-Allmaras (SA) are used in the present study. The results are generally in agreement with other implementations of these models in structured-grid CFD codes. Results indicate that USM3D provides accurate simulations for complex aerodynamic configurations with propulsion integration.

  15. The Synergy Between Total Scattering and Advanced Simulation Techniques: Quantifying Geopolymer Gel Evolution

    Energy Technology Data Exchange (ETDEWEB)

    White, Claire [Los Alamos National Laboratory; Bloomer, Breaunnah E. [Los Alamos National Laboratory; Provis, John L. [The University of Melbourne; Henson, Neil J. [Los Alamos National Laboratory; Page, Katharine L. [Los Alamos National Laboratory

    2012-05-16

    With the ever increasing demands for technologically advanced structural materials, together with emerging environmental consciousness due to climate change, geopolymer cement is fast becoming a viable alternative to traditional cements due to proven mechanical engineering characteristics and the reduction in CO2 emitted (approximately 80% less CO2 emitted compared to ordinary Portland cement). Nevertheless, much remains unknown regarding the kinetics of the molecular changes responsible for nanostructural evolution during the geopolymerization process. Here, in-situ total scattering measurements in the form of X-ray pair distribution function (PDF) analysis are used to quantify the extent of reaction of metakaolin/slag alkali-activated geopolymer binders, including the effects of various activators (alkali hydroxide/silicate) on the kinetics of the geopolymerization reaction. Restricting quantification of the kinetics to the initial ten hours of reaction does not enable elucidation of the true extent of the reaction, but using X-ray PDF data obtained after 128 days of reaction enables more accurate determination of the initial extent of reaction. The synergies between the in-situ X-ray PDF data and simulations conducted by multiscale density functional theory-based coarse-grained Monte Carlo analysis are outlined, particularly with regard to the potential for the X-ray data to provide a time scale for kinetic analysis of the extent of reaction obtained from the multiscale simulation methodology.

  16. A Modified Time Advancement Algorithm for Optimizing Channel Flow Analysis in Direct Numerical Simulation Method

    Directory of Open Access Journals (Sweden)

    E. Rajabi

    2014-01-01

    Full Text Available In this research a direct numerical simulation (DNS of turbulent flow is performed in a geometrically standard case like plane channel flow. Pseudo spectral (PS method is used due to geometry specifications and very high accuracy achieved despite relatively few grid points. A variable time-stepping algorithm is proposed which may reduce requirement of computational cost in simulation of such wall-bounded flow. Channel flow analysis is performed with both constant and varied time-step for 128 × 65×128 grid points. The time advancement is carried out by implicit third-order backward differentiation scheme for linear terms and explicit forward Euler for nonlinear convection term. PS method is used in Cartesian coordinates with Chebychev polynomial expansion in normal direction for one non-periodic boundary condition. Also Fourier series is employed in stream-wise and span-wise directions for two periodic boundary conditions. The friction Reynolds number is about Reτ=175 based on a friction velocity and channel half width. Standard common rotational form was chosen for discritization of nonlinear convective term of Navier-Stocks equation. The comparison is made between turbulent quantities such as the turbulent statistics, Reynolds stress, wall shear velocity, standard deviation of (u and total normalized energy of instantaneous velocities in both time-discretization methods. The results show that if final decision rests on economics, the proposed variable time-stepping algorithm will be proper choice which satisfies the accuracy and reduces the computational cost.

  17. Fundamental Research on Percussion Drilling: Improved rock mechanics analysis, advanced simulation technology, and full-scale laboratory investigations

    Energy Technology Data Exchange (ETDEWEB)

    Michael S. Bruno

    2005-12-31

    This report summarizes the research efforts on the DOE supported research project Percussion Drilling (DE-FC26-03NT41999), which is to significantly advance the fundamental understandings of the physical mechanisms involved in combined percussion and rotary drilling, and thereby facilitate more efficient and lower cost drilling and exploration of hard-rock reservoirs. The project has been divided into multiple tasks: literature reviews, analytical and numerical modeling, full scale laboratory testing and model validation, and final report delivery. Literature reviews document the history, pros and cons, and rock failure physics of percussion drilling in oil and gas industries. Based on the current understandings, a conceptual drilling model is proposed for modeling efforts. Both analytical and numerical approaches are deployed to investigate drilling processes such as drillbit penetration with compression, rotation and percussion, rock response with stress propagation, damage accumulation and failure, and debris transportation inside the annulus after disintegrated from rock. For rock mechanics modeling, a dynamic numerical tool has been developed to describe rock damage and failure, including rock crushing by compressive bit load, rock fracturing by both shearing and tensile forces, and rock weakening by repetitive compression-tension loading. Besides multiple failure criteria, the tool also includes a damping algorithm to dissipate oscillation energy and a fatigue/damage algorithm to update rock properties during each impact. From the model, Rate of Penetration (ROP) and rock failure history can be estimated. For cuttings transport in annulus, a 3D numerical particle flowing model has been developed with aid of analytical approaches. The tool can simulate cuttings movement at particle scale under laminar or turbulent fluid flow conditions and evaluate the efficiency of cutting removal. To calibrate the modeling efforts, a series of full-scale fluid hammer

  18. Analytical modeling and simulation of electrochemical charge/discharge behavior of Si thin film negative electrodes in Li-ion cells

    Science.gov (United States)

    Jagannathan, M.; Chandran, K. S. Ravi

    2014-02-01

    Physically-based analytical models that provide insights into the diffusion and/or interface charge transfer effects in bulk (lithiating/delithiating) electrodes are needed to truly assess the performance/limitations of electrode materials for Li-ion batteries. In this context, an analytical modeling framework is constructed here to predict the electrochemical charge-discharge characteristics during lithiation and delithiation of solid amorphous Si (a-Si) thin film electrodes. The framework includes analytical expressions that satisfy Fick's second law for Li transport and the requisite flux boundary conditions of lithiation and delithiation steps. The expressions are derived here by the method of separation of variables. They enable the determination of transient Li concentration profiles in the thin film electrode as a function of state of charge/discharge. The time-dependent electrode surface concentrations (at the electrode-electrolyte interface) obtained from these profiles were used to determine the activation overpotentials and thus, the non-equilibrium cell potentials, as a function of state of charge/discharge using Butler-Volmer kinetics. The simulated charge/discharge characteristics agreed well with the experimental data of a-Si thin film electrodes obtained at different C-rates. The model offers insights into how the charge-discharge behavior is controlled by diffusion limitation within electrode and/or the activation overpotentials at the interface. The analytical framework is also shown to predict successfully the hysteretic behavior of lithiation/delithiation voltage curves.

  19. Analytical and experimental evaluation of joining silicon nitride to metal and silicon carbide to metal for advanced heat engine applications. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kang, S.; Selverian, J.H.; O`Neil, D.; Kim, H. [GTE Labs., Inc., Waltham, MA (US); Kim, K. [Brown Univ., Providence, RI (US). Div. of Engineering

    1993-05-01

    This report summarizes the results of Phase 2 of Analytical and Experimental Evaluation of Joining Silicon Nitride to Metal and Silicon Carbide to Metal for Advanced Heat Engine Applications. A general methodology was developed to optimize the joint geometry and material systems for 650{degrees}C applications. Failure criteria were derived to predict the fracture of the braze and ceramic. Extensive finite element analyses (FEA) were performed to examine various joint geometries and to evaluate the affect of different interlayers on the residual stress state. Also, material systems composed of coating materials, interlayers, and braze alloys were developed for the program based on the chemical stability and strength of the joints during processing, and service. The FEA results were compared with experiments using two methods: (1) an idealized strength relationship of the ceramic, and (2) a probabilistic analysis of the ceramic strength (NASA CARES). The results showed that the measured strength of the joint reached 30--80% of the strength predicted by FEA. Also, potential high-temperature braze alloys were developed and evaluated for the high-temperature application of ceramic-metal joints. 38 tabs, 29 figs, 20 refs.

  20. Discrete-event simulation of coordinated multi-point joint transmission in LTE-Advanced with constrained backhaul

    DEFF Research Database (Denmark)

    Artuso, Matteo; Christiansen, Henrik Lehrmann

    2014-01-01

    Inter-cell interference in LTE-Advanced can be mitigated using coordinated multi-point (CoMP) techniques with joint transmission of user data . However, this requires tight coordination of the eNodeBs, usin g the X2 interface. In this paper we use discrete-event simulation to evaluate the latency...

  1. Development of advanced spent fuel management process. The fabrication and oxidation behavior of simulated metallized spent fuel

    International Nuclear Information System (INIS)

    The simulated metallized spent fuel ingots were fabricated and evaluated the oxidation rates and the activation energies under several temperature conditions to develop an advanced spent fuel management process. It was also checked the alloying characteristics of the some elements with metal uranium. (Author). 3 refs., 1 tab., 36 figs

  2. ADVANCED SIMULATION CAPABILITY FOR ENVIRONMENTAL MANAGEMENT- CURRENT STATUS AND PHASE II DEMONSTRATION RESULTS

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, R.

    2013-02-26

    The U.S. Department of Energy (USDOE) Office of Environmental Management (EM), Office of Soil and Groundwater, is supporting development of the Advanced Simulation Capability for Environmental Management (ASCEM). ASCEM is a state-of-the-art scientific tool and approach for understanding and predicting contaminant fate and transport in natural and engineered systems. The modular and open source high-performance computing tool facilitates integrated approaches to modeling and site characterization that enable robust and standardized assessments of performance and risk for EM cleanup and closure activities. The ASCEM project continues to make significant progress in development of computer software capabilities with an emphasis on integration of capabilities in FY12. Capability development is occurring for both the Platform and Integrated Toolsets and High-Performance Computing (HPC) Multiprocess Simulator. The Platform capabilities provide the user interface and tools for end-to-end model development, starting with definition of the conceptual model, management of data for model input, model calibration and uncertainty analysis, and processing of model output, including visualization. The HPC capabilities target increased functionality of process model representations, toolsets for interaction with Platform, and verification and model confidence testing. The Platform and HPC capabilities are being tested and evaluated for EM applications in a set of demonstrations as part of Site Applications Thrust Area activities. The Phase I demonstration focusing on individual capabilities of the initial toolsets was completed in 2010. The Phase II demonstration completed in 2012 focused on showcasing integrated ASCEM capabilities. For Phase II, the Hanford Site deep vadose zone (BC Cribs) served as an application site for an end-to-end demonstration of capabilities, with emphasis on integration and linkages between the Platform and HPC components. Other demonstrations

  3. Computer simulation of homogenization of boric acid in a pressurizer of the advanced nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Rosa, Jose E.P. da; Moreira, Maria de L., E-mail: jeduird@hotmail.com, E-mail: malu@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Oliveira, Andre F. de, E-mail: eafoliveira@ien.gov.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear

    2013-07-01

    The reactivity of a water cooled reactor is controlled using control rods or boron dilution in water of the primary circuit. The boron-10 ({sup 10} B) is an efficient neutron absorber, especially when used in the absorption of thermal neutrons. Transient studies with disabilities in the homogenization of boron in PWR reactors become important as the boric acid solution is added to the primary circuit coolant in order to help control the fission rate in the reactor core. After reactor shutdown, the boron present in coolant has the function of maintaining reactor subcriticality. If low concentrated boron solution enters in the primary circuit, it becomes necessary to inject boron and to assure that the coolant will be well homogenized in order to increase the concentration and thus preventing water with small amounts of boron to reach the core. The aim of this study is to simulate the boron homogenization in the pressurizer of an advanced nuclear reactor. It is used a test section, which represents a quarter of a modular nuclear reactor pressurizer. By using the CFX code, a computer program that allows thermal hydraulic analysis of different types of flow, three examples were simulated using different operating conditions. With the results, it was analyzed the parameters that could influence this homogenization. Case studies such as variation of the dimensions of the water inlet and outlet tubes, flow variation and change in positioning of entrances and exits were made with the goal of finding parameters that could help the optimization of the homogenization of boron. The results confirm that the issues analyzed can be changed in the project in order to obtain the best operating condition. (author)

  4. SIROCCO project: 15 advanced instructor desk and 4 simulated control room for 900MW and 1300MW EDF power plant simulators

    International Nuclear Information System (INIS)

    This presentation describes the fifteen advanced instructors station and four simulated control delivered to EDF in the frame of the SIROCCO project by the Consortium formed by ATOS Origin, CORYS Tess, for the Electricite de France (EDF). These instructor stations are installed on fifteen replica training simulators located on different sites throughout France for the purposes of improving the job-related training of the EDF PWR nuclear power plant operating teams. This covers all 900 MW and 1300MW nuclear power plant of EDF. The simulated control rooms are installed on maintenance platform located at EDF and the consortium facilities. The consortium uses it to maintain and upgrade the simulators. EDF uses it to validate the upgrade delivered by the consortium before on site installation and to perform engineering analysis. This presentation sets out successively: - The major advantages of the generic and configurable connected module concept for flexible and quick adaptation to different simulators; - The innovative functionalities of the advanced Instructor Desk (IS) which make the instructor's tasks of preparation, monitoring and postanalysis of a training session easier and more homogeneous; - The use of the Simulated Control Room (SCR) for training purposes but also for those of maintenance and design studies for upgrades of existing control rooms

  5. Advanced Research and Education in Electrical Drives by Using Digital Real-Time Hardware-in-the-Loop Simulation

    DEFF Research Database (Denmark)

    Bojoi, R.; Profumo, F.; Griva, G.;

    2002-01-01

    The authors present in this paper a digital real-time hardware-in-the-loop simulation of a three-phase induction motor drive. The main real-time simulation tool is the dSPACE DS1103 PPC Controller Board which simulates the power and signal conditioning parts. The control algorithm of the virtual...... drive has been implemented on the Evaluation Board of TMS320F240 DSP. The experimental results validate this solution as a powerful tool to be used in research and advanced education. Thus, the students can put in practic the theory without spending too much time with details concerning the hardware...

  6. Performance experiments with alternative advanced teleoperator control modes for a simulated solar maximum satellite repair

    Science.gov (United States)

    Das, H.; Zak, H.; Kim, W. S.; Bejczy, A. K.; Schenker, P. S.

    1992-01-01

    Experiments are described which were conducted at the JPL Advanced Teleoperator Lab to demonstrate and evaluate the effectiveness of various teleoperator control modes in the performance of a simulated Solar Max Satellite Repair (SMSR) task. THe SMSR was selected as a test because it is very rich in performance capability requirements and it actually has been performed by two EVA astronauts in the Space Shuttle Bay in 1984. The main subtasks are: thermal blanket removal; installation of a hinge attachment for electrical panel opening; opening of electrical panel; removal of electrical connectors; relining of cable bundles; replacement of electrical panel; securing parts and cables; re-mate electrical connectors; closing of electrical panel; and reinstating thermal blanket. The current performance experiments are limited to thermal blanket cutting, electrical panel unbolting and handling electrical bundles and connectors. In one formal experiment even different control modes were applied to the unbolting and reinsertion of electrical panel screws subtasks. The seven control modes are alternative combinations of manual position and rate control with force feedback and remote compliance referenced to force-torque sensor information. Force-torque sensor and end effector position data and task completion times were recorded for analysis and quantification of operator performance.

  7. Numerical simulation and performance investigation of an advanced adsorption desalination cycle

    KAUST Repository

    Thu, Kyaw

    2013-01-01

    Low temperature waste heat-driven adsorption desalination (AD) cycles offer high potential as one of the most economically viable and environmental-friendly desalination methods. This article presents the development of an advanced adsorption desalination cycle that employs internal heat recovery between the evaporator and the condenser, utilizing an encapsulated evaporator-condenser unit for effective heat transfer. A simulation model has been developed based on the actual sorption characteristics of the adsorbent-adsorbate pair, energy and mass balances applied to the components of the AD cycle. With an integrated design, the temperature in the evaporator and the vapor pressurization of the adsorber are raised due to the direct heat recovery from the condenser, resulting in the higher water production rates, typically improved by as much as three folds of the conventional AD cycle. In addition, the integrated design eliminates two pumps, namely, the condenser cooling water and the chilled water pumps, lowering the overall electricity consumption. The performance of the cycle is analyzed at assorted heat source and cooling water temperatures, and different cycle times as well as the transient heat transfer coefficients of the evaporation and condensation. © 2012 Elsevier B.V.

  8. An expanded framework for the advanced computational testing and simulation toolkit

    Energy Technology Data Exchange (ETDEWEB)

    Marques, Osni A.; Drummond, Leroy A.

    2003-11-09

    The Advanced Computational Testing and Simulation (ACTS) Toolkit is a set of computational tools developed primarily at DOE laboratories and is aimed at simplifying the solution of common and important computational problems. The use of the tools reduces the development time for new codes and the tools provide functionality that might not otherwise be available. This document outlines an agenda for expanding the scope of the ACTS Project based on lessons learned from current activities. Highlights of this agenda include peer-reviewed certification of new tools; finding tools to solve problems that are not currently addressed by the Toolkit; working in collaboration with other software initiatives and DOE computer facilities; expanding outreach efforts; promoting interoperability, further development of the tools; and improving functionality of the ACTS Information Center, among other tasks. The ultimate goal is to make the ACTS tools more widely used and more effective in solving DOE's and the nation's scientific problems through the creation of a reliable software infrastructure for scientific computing.

  9. Advisor 2.0: A Second-Generation Advanced Vehicle Simulator for Systems Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wipke, K.; Cuddy, M.; Bharathan, D.; Burch, S.; Johnson, V.; Markel, A.; Sprik, S.

    1999-03-23

    The National Renewable Energy Laboratory has recently publicly released its second-generation advanced vehicle simulator called ADVISOR 2.0. This software program was initially developed four years ago, and after several years of in-house usage and evolution, the tool is now available to the public through a new vehicle systems analysis World Wide Web page. ADVISOR has been applied to many different systems analysis problems, such as helping to develop the SAE J1711 test procedure for hybrid vehicles and helping to evaluate new technologies as part of the Partnership for a New Generation of Vehicles (PNGV) technology selection process. The model has been and will continue to be benchmarked and validated with other models and with real vehicle test data. After two months of being available on the Web, more than 100 users have downloaded ADVISOR. ADVISOR 2.0 has many new features, including an easy-to-use graphical user interface, a detailed exhaust aftertreatment thermal model, and complete browser-based documentation. Future work will include adding to the library of components available in ADVISOR, including optimization functionality, and linking with a more detailed fuel cell model.

  10. Investigation of Alien Wavelength Quality in Live Multi-Domain, Multi-Vendor Link Using Advanced Simulation Tool

    DEFF Research Database (Denmark)

    Petersen, Martin Nordal; Nuijts, Roeland; Bjorn, Lars Lange

    2014-01-01

    This article presents an advanced optical model for simulation of alien wavelengths in multi-domain and multi-vendor dense wavelength-division multiplexing networks. The model aids optical network planners with a better understanding of the non-linear effects present in dense wavelength-division ......This article presents an advanced optical model for simulation of alien wavelengths in multi-domain and multi-vendor dense wavelength-division multiplexing networks. The model aids optical network planners with a better understanding of the non-linear effects present in dense wavelength......-division multiplexing systems and better utilization of alien wavelengths in future applications. The limiting physical effects for alien wavelengths are investigated in relation to power levels, channel spacing, and other factors. The simulation results are verified through experimental setup in live multi...

  11. Simulation of population response to ionizing radiation in an ecosystem with a limiting resource--Model and analytical solutions.

    Science.gov (United States)

    Sazykina, Tatiana G; Kryshev, Alexander I

    2016-01-01

    A dynamic mathematical model is formulated, predicting the development of radiation effects in a generic animal population, inhabiting an elemental ecosystem 'population-limiting resource'. Differential equations of the model describe the dynamic responses to radiation damage of the following population characteristics: gross biomass; intrinsic fractions of healthy and reversibly damaged tissues in biomass; intrinsic concentrations of the self-repairing pool and the growth factor; and amount of the limiting resource available in the environment. Analytical formulae are found for the steady states of model variables as non-linear functions of the dose rate of chronic radiation exposure. Analytical solutions make it possible to predict the expected severity of radiation effects in a model ecosystem, including such endpoints as morbidity, mortality, life shortening, biosynthesis, and population biomass. Model parameters are selected from species data on lifespan, physiological growth and mortality rates, and individual radiosensitivity. Thresholds for population extinction can be analytically calculated for different animal species, examples are provided for generic mice and wolf populations. The ecosystem model demonstrates a compensatory effect of the environment on the development of radiation effects in wildlife. The model can be employed to construct a preliminary scale 'radiation exposure-population effects' for different animal species; species can be identified, which are vulnerable at a population level to chronic radiation exposure. PMID:26408836

  12. Analysis of simulation tools for the study of advanced marine power systems

    OpenAIRE

    Brochard, Paul Eugene

    1992-01-01

    The United States Navy is at a crossroads in the design of ship's engineering plants. Advances in solid-state power electronics combined with a shift to gas turbine powered propulsion and electric plants has placed renewed emphasis on developing advanced power systems. These advanced power systems may combine the prime movers associated with propulsion and electric power generation into an integrated system. The development of advanced electric distribution systems and propulsion derived ship...

  13. Advanced Unsteady Turbulent Combustion Simulation Capability for Space Propulsion Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation proposed here is a high performance, high fidelity simulation capability to enable accurate, fast and robust simulation of unsteady turbulent,...

  14. Update on ORNL TRANSFORM Tool: Simulating Multi-Module Advanced Reactor with End-to-End I&C

    Energy Technology Data Exchange (ETDEWEB)

    Hale, Richard Edward [ORNL; Fugate, David L [ORNL; Cetiner, Sacit M [ORNL; Qualls, A L [ORNL

    2015-05-01

    The Small Modular Reactor (SMR) Dynamic System Modeling Tool project is in the fourth year of development. The project is designed to support collaborative modeling and study of various advanced SMR (non-light water cooled reactor) concepts, including the use of multiple coupled reactors at a single site. The focus of this report is the development of a steam generator and drum system model that includes the complex dynamics of typical steam drum systems, the development of instrumentation and controls for the steam generator with drum system model, and the development of multi-reactor module models that reflect the full power reactor innovative small module design concept. The objective of the project is to provide a common simulation environment and baseline modeling resources to facilitate rapid development of dynamic advanced reactor models; ensure consistency among research products within the Instrumentation, Controls, and Human-Machine Interface technical area; and leverage cross-cutting capabilities while minimizing duplication of effort. The combined simulation environment and suite of models are identified as the TRANSFORM tool. The critical elements of this effort include (1) defining a standardized, common simulation environment that can be applied throughout the Advanced Reactors Technology program; (2) developing a library of baseline component modules that can be assembled into full plant models using available geometry, design, and thermal-hydraulic data; (3) defining modeling conventions for interconnecting component models; and (4) establishing user interfaces and support tools to facilitate simulation development (i.e., configuration and parameterization), execution, and results display and capture.

  15. Advanced Approach to Consider Aleatory and Epistemic Uncertainties for Integral Accident Simulations

    International Nuclear Information System (INIS)

    The use of best-estimate codes together with realistic input data generally requires that all potentially important epistemic uncertainties which may affect the code prediction are considered in order to get an adequate quantification of the epistemic uncertainty of the prediction as an expression of the existing imprecise knowledge. To facilitate the performance of the required epistemic uncertainty analyses, methods and corresponding software tools are available like, for instance, the GRS-tool SUSA (Software for Uncertainty and Sensitivity Analysis). However, for risk-informed decision-making, the restriction on epistemic uncertainties alone is not enough. Transients and accident scenarios are also affected by aleatory uncertainties which are due to the unpredictable nature of phenomena. It is essential that aleatory uncertainties are taken into account as well, not only in a simplified and supposedly conservative way but as realistic as possible. The additional consideration of aleatory uncertainties, for instance, on the behavior of the technical system, the performance of plant operators, or on the behavior of the physical process provides a quantification of probabilistically significant accident sequences. Only if a safety analysis is able to account for both epistemic and aleatory uncertainties in a realistic manner, it can provide a well-founded risk-informed answer for decision-making. At GRS, an advanced probabilistic dynamics method was developed to address this problem and to provide a more realistic modeling and assessment of transients and accident scenarios. This method allows for an integral simulation of complex dynamic processes particularly taking into account interactions between the plant dynamics as simulated by a best-estimate code, the dynamics of operator actions and the influence of epistemic and aleatory uncertainties. In this paper, the GRS method MCDET (Monte Carlo Dynamic Event Tree) for probabilistic dynamics analysis is explained

  16. WRF4G project: Advances in running climate simulations on the EGI Infrastructure

    Science.gov (United States)

    Blanco, Carlos; Cofino, Antonio S.; Fernández Quiruelas, Valvanuz; García, Markel; Fernández, Jesús

    2014-05-01

    The Weather Research and Forecasting For Grid (WRF4G) project is a two-year Spanish National R&D project, which has started in 2011. It is now a well established project, involving scientists and technical staff from several institutions, which contribute results to international initiatives such as CORDEX and European FP7 projects such as SPECS and EUPORIAS. The aim of the WRF4G project is to homogenize access hybrid Distributed Computer Infrastructures (DCIs), such as HPC and Grid infrastructures, for climate researchers. Additionally, it provides a productive interface to accomplish ambitious climate experiments such as regional hind-cast/forecast and sensitivity studies. Although Grid infrastructures are very powerful, they have some drawbacks for executing climate applications such as the WRF model. This makes necessary to encapsulate the applications in a middleware in order to provide the appropriate services for monitoring and management. Therefore, the challenge of the WRF4G project is to develop a generic adaptation framework (WRF4G framework) to disseminate it to the scientific community. The framework aims at simplifying the model access by releasing climate scientists from technical and computational aspects. In this contribution, we present some new advances of the WRF4G framework, including new components for designing experiments, simulation monitoring and data management. Additionally, we will show how WRF4G makes possible to run complex experiments on EGI infrastructures concurrently over several VOs such as esr and earth.vo.ibergrid. http://www.meteo.unican.es/software/wrf4g This work has been partially funded by the European Regional Development Fund (ERDF) and the Spanish National R&D Plan 2008-2011 (CGL2011-28864, WRF4G)

  17. Noble gas and hydrocarbon tracers in multiphase unconventional hydrocarbon systems: Toward integrated advanced reservoir simulators

    Science.gov (United States)

    Darrah, T.; Moortgat, J.; Poreda, R. J.; Muehlenbachs, K.; Whyte, C. J.

    2015-12-01

    Although hydrocarbon production from unconventional energy resources has increased dramatically in the last decade, total unconventional oil and gas recovery from black shales is still less than 25% and 9% of the totals in place, respectively. Further, the majority of increased hydrocarbon production results from increasing the lengths of laterals, the number of hydraulic fracturing stages, and the volume of consumptive water usage. These strategies all reduce the economic efficiency of hydrocarbon extraction. The poor recovery statistics result from an insufficient understanding of some of the key physical processes in complex, organic-rich, low porosity formations (e.g., phase behavior, fluid-rock interactions, and flow mechanisms at nano-scale confinement and the role of natural fractures and faults as conduits for flow). Noble gases and other hydrocarbon tracers are capably of recording subsurface fluid-rock interactions on a variety of geological scales (micro-, meso-, to macro-scale) and provide analogs for the movement of hydrocarbons in the subsurface. As such geochemical data enrich the input for the numerical modeling of multi-phase (e.g., oil, gas, and brine) fluid flow in highly heterogeneous, low permeability formations Herein we will present a combination of noble gas (He, Ne, Ar, Kr, and Xe abundances and isotope ratios) and molecular and isotopic hydrocarbon data from a geographically and geologically diverse set of unconventional hydrocarbon reservoirs in North America. Specifically, we will include data from the Marcellus, Utica, Barnett, Eagle Ford, formations and the Illinois basin. Our presentation will include geochemical and geological interpretation and our perspective on the first steps toward building an advanced reservoir simulator for tracer transport in multicomponent multiphase compositional flow (presented separately, in Moortgat et al., 2015).

  18. Analytical evaluation on loss of off-side electric power simulation of the High Temperature Engineering Test Reactor

    International Nuclear Information System (INIS)

    A rise-to-power test of the high temperature engineering test reactor (HTTR) started on September 28 in 1999 for establishing and upgrading the technological basis for the high temperature gas-cooled reactor (HTGR). A loss of off-site electric power test of the HTTR from the normal operation under 15 and 30 MW thermal power will be carried out in the rise-to-power test. Analytical evaluations on transient behaviors of the reactor and plant during the loss of off-site electric power were conducted. These estimations are proposed as benchmark problems for the IAEA coordinated research program on 'Evaluation of HTGR Performance'. This report describes an event scenario of transient during the loss of off-site electric power, the outline of major components and system, detailed thermal and nuclear data set for these problems and pre-estimation results of the benchmark problems by an analytical code 'ACCORD' for incore and plant dynamics of the HTGR. (author)

  19. Web-based Visual Analytics for Extreme Scale Climate Science

    Energy Technology Data Exchange (ETDEWEB)

    Steed, Chad A [ORNL; Evans, Katherine J [ORNL; Harney, John F [ORNL; Jewell, Brian C [ORNL; Shipman, Galen M [ORNL; Smith, Brian E [ORNL; Thornton, Peter E [ORNL; Williams, Dean N. [Lawrence Livermore National Laboratory (LLNL)

    2014-01-01

    In this paper, we introduce a Web-based visual analytics framework for democratizing advanced visualization and analysis capabilities pertinent to large-scale earth system simulations. We address significant limitations of present climate data analysis tools such as tightly coupled dependencies, ineffi- cient data movements, complex user interfaces, and static visualizations. Our Web-based visual analytics framework removes critical barriers to the widespread accessibility and adoption of advanced scientific techniques. Using distributed connections to back-end diagnostics, we minimize data movements and leverage HPC platforms. We also mitigate system dependency issues by employing a RESTful interface. Our framework embraces the visual analytics paradigm via new visual navigation techniques for hierarchical parameter spaces, multi-scale representations, and interactive spatio-temporal data mining methods that retain details. Although generalizable to other science domains, the current work focuses on improving exploratory analysis of large-scale Community Land Model (CLM) and Community Atmosphere Model (CAM) simulations.

  20. Development of Advanced Wear and Corrosion Resistant Systems Through Laser Surface Alloying and Materials Simulations

    Energy Technology Data Exchange (ETDEWEB)

    R. P. Martukanitz and S. Babu

    2007-05-03

    Laser surfacing in the form of cladding, alloying, and modifications are gaining widespread use because of its ability to provide high deposition rates, low thermal distortion, and refined microstructure due to high solidification rates. Because of these advantages, laser surface alloying is considered a prime candidate for producing ultra-hard coatings through the establishment or in situ formation of composite structures. Therefore, a program was conducted by the Applied Research Laboratory, Pennsylvania State University and Oak Ridge National Laboratory to develop the scientific and engineering basis for performing laser-based surface modifications involving the addition of hard particles, such as carbides, borides, and nitrides, within a metallic matrix for improved wear, fatigue, creep, and corrosion resistance. This has involved the development of advanced laser processing and simulation techniques, along with the refinement and application of these techniques for predicting and selecting materials and processing parameters for the creation of new surfaces having improved properties over current coating technologies. This program has also resulted in the formulation of process and material simulation tools capable of examining the potential for the formation and retention of composite coatings and deposits produced using laser processing techniques, as well as positive laboratory demonstrations in producing these coatings. In conjunction with the process simulation techniques, the application of computational thermodynamic and kinetic models to design laser surface alloying materials was demonstrated and resulted in a vast improvement in the formulation of materials used for producing composite coatings. The methodology was used to identify materials and to selectively modify microstructures for increasing hardness of deposits produced by the laser surface alloying process. Computational thermodynamic calculations indicated that it was possible to induce the

  1. Development of Advanced Electrochemical Emission Spectroscopy for Monitoring Corrosion in Simulated DOE Liquid Waste

    Energy Technology Data Exchange (ETDEWEB)

    Digby Macdonald; Brian Marx; Balaji Soundararajan; Morgan Smith

    2005-07-28

    The different tasks that have been carried out under the current program are as follows: (1) Theoretical and experimental assessment of general corrosion of iron/steel in borate buffer solutions by using electrochemical impedance spectroscopy (EIS), ellipsometry and XPS techniques; (2) Development of a damage function analysis (DFA), which would help in predicting the accumulation of damage due to pitting corrosion in an environment prototypical of DOE liquid waste systems; (3) Experimental measurement of crack growth rate, acoustic emission signals, and coupling currents for fracture in carbon and low alloy steels as functions of mechanical (stress intensity), chemical (conductivity), electrochemical (corrosion potential, ECP), and microstructural (grain size, precipitate size, etc) variables in a systematic manner, with particular attention being focused on the structure of the noise in the current and its correlation with the acoustic emissions; (4) Development of fracture mechanisms for carbon and low alloy steels that are consistent with the crack growth rate, coupling current data and acoustic emissions; (5) Inserting advanced crack growth rate models for SCC into existing deterministic codes for predicting the evolution of corrosion damage in DOE liquid waste storage tanks; (6) Computer simulation of the anodic and cathodic activity on the surface of the steel samples in order to exactly predict the corrosion mechanisms; (7) Wavelet analysis of EC noise data from steel samples undergoing corrosion in an environment similar to that of the high level waste storage containers, to extract data pertaining to general, pitting and stress corrosion processes, from the overall data. The work has yielded a number of important findings, including an unequivocal demonstration of the role of chloride ion in passivity breakdown on nickel in terms of cation vacancy generation within the passive film, the first detection and characterization of individual micro fracture

  2. Big data to smart data in Alzheimer's disease: Real-world examples of advanced modeling and simulation.

    Science.gov (United States)

    Haas, Magali; Stephenson, Diane; Romero, Klaus; Gordon, Mark Forrest; Zach, Neta; Geerts, Hugo

    2016-09-01

    Many disease-modifying clinical development programs in Alzheimer's disease (AD) have failed to date, and development of new and advanced preclinical models that generate actionable knowledge is desperately needed. This review reports on computer-based modeling and simulation approach as a powerful tool in AD research. Statistical data-analysis techniques can identify associations between certain data and phenotypes, such as diagnosis or disease progression. Other approaches integrate domain expertise in a formalized mathematical way to understand how specific components of pathology integrate into complex brain networks. Private-public partnerships focused on data sharing, causal inference and pathway-based analysis, crowdsourcing, and mechanism-based quantitative systems modeling represent successful real-world modeling examples with substantial impact on CNS diseases. Similar to other disease indications, successful real-world examples of advanced simulation can generate actionable support of drug discovery and development in AD, illustrating the value that can be generated for different stakeholders. PMID:27327540

  3. Large-scale simulations on thermal-hydraulics in fuel bundles of advanced nuclear reactors (Annual Report of the Earth Simulator Center, Dec 2008, 2007 issue)

    International Nuclear Information System (INIS)

    In order to predict the water-vapor two-phase flow dynamics in a fuel bundle of an advanced light-water reactor, large-scale numerical simulations were performed using a highly parallel-vector supercomputer, the earth simulator. Although conventional analysis methods such as subchannel codes and system analysis codes need composition equations based on the experimental data, it is difficult to obtain high prediction accuracy when experimental data to obtain the composition equations. Then, the present large-scale direct simulation method of water-vapor two-phase flow was proposed. The void fraction distribution in a fuel bundle under boiling heat transfer condition was analyzed and the bubble dynamics around the fuel rod surface were predicted quantitatively. (author)

  4. Recent advances on mesoscopic simulation of dislocation dynamics; Recientes avances en simulacion mesoscopica de la dinamica de dislocaciones

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Garcia, D.; Dominguez-Rodriguez, A.; Devincre, B.; Kubin, L. P.

    2001-07-01

    Recent advances in the description of dislocation dynamics are presented. Systems considered have realistic dislocation densities (i.e. densities close to those measured during the plastic deformation of single crystals {approx_equal}10''12 m''-2). The description is made through computer simulations in a bidimensional frame. Special emphasis will be made concerning the simplifications adopted, as well as the achievements. (Author) 3 refs.

  5. Experimental simulation of LOCA in a PWHR : analytical study of similarity of thermal response between fuel rod simulators and nuclear fuel rods under reflood conditions

    International Nuclear Information System (INIS)

    For the safety analysis of a nuclear reactor, the similarity of the thermal response of an electrically heated Fuel Rod Simulator (FRS), mostly used in Loss-of-Coolant-Accident (LOCA) experiments, to that of a nuclear fuel rod is of great significance. The present analysis describes the characteristics and the similarity of thermal response fuel rods under reflood conditions of LOCA. The analysis has shown that the thermal response of a nuclear fuel rod can be well simulated by the use of an electrically heated FRS. (author). 7 refs., 12 figs

  6. Prediction of the dynamic oscillation threshold of a clarinet model: comparison between analytical predictions and simulation results

    OpenAIRE

    Bergeot, Baptiste; De Almeida, André,; Vergez, Christophe; Gazengel, Bruno

    2013-01-01

    Simple models of clarinet instruments based on iterated maps have been used in the past to successfully estimate the threshold of oscillation of this instrument as a function of a constant blowing pressure. However, when the blowing pressure gradually increases through time, the oscillations appear at a much higher value than what is predicted in the static case. This is known as bifurcation delay, a phenomenon studied in [1] for a clarinet model. In numerical simulations the bifurcation dela...

  7. Symplectic partitioned Runge-Kutta method based on the eighth-order nearly analytic discrete operator and its wavefield simulations

    Institute of Scientific and Technical Information of China (English)

    Zhang Chao-Yuan; Ma Xiao; Yang Lei; Song Guo-Jie

    2014-01-01

    We propose a symplectic partitioned Runge-Kutta (SPRK) method with eighth-order spatial accuracy based on the extended Hamiltonian system of the acoustic wave equation. Known as the eighth-order NSPRK method, this technique uses an eighth-order accurate nearly analytic discrete (NAD) operator to discretize high-order spatial differential operators and employs a second-order SPRK method to discretize temporal derivatives. The stability criteria and numerical dispersion relations of the eighth-order NSPRK method are given by a semi-analytical method and are tested by numerical experiments. We also show the differences of the numerical dispersions between the eighth-order NSPRK method and conventional numerical methods such as the fourth-order NSPRK method, the eighth-order Lax-Wendroff correction (LWC) method and the eighth-order staggered-grid (SG) method. The result shows that the ability of the eighth-order NSPRK method to suppress the numerical dispersion is obviously superior to that of the conventional numerical methods. In the same computational environment, to eliminate visible numerical dispersions, the eighth-order NSPRK is approximately 2.5 times faster than the fourth-order NSPRK and 3.4 times faster than the fourth-order SPRK, and the memory requirement is only approximately 47.17%of the fourth-order NSPRK method and 49.41%of the fourth-order SPRK method, which indicates the highest computational efficiency. Modeling examples for the two-layer models such as the heterogeneous and Marmousi models show that the wavefields generated by the eighth-order NSPRK method are very clear with no visible numerical dispersion. These numerical experiments illustrate that the eighth-order NSPRK method can effectively suppress numerical dispersion when coarse grids are adopted. Therefore, this method can greatly decrease computer memory requirement and accelerate the forward modeling productivity. In general, the eighth-order NSPRK method has tremendous potential value

  8. Analytical laboratory in NUCEF

    International Nuclear Information System (INIS)

    An analytical laboratory was completed in NUCEF (the Nuclear Fuel Cycle Safety Engineering Research Facility) of JAERI. NUCEF has two critical facilities (STACY and TRACY) and a fuel treatment system for criticality safety research. In addition, the facility has BECKY (Back-end Cycle Key Elements Research Facility) for the research on advanced reprocessing technology, TRU waste management and so on. This present report describes the design conditions and structure of the analytical laboratory as well as the specification of each analytical equipment. (J.P.N.)

  9. Time-dependent simulation and analytical modelling of electronic Mach-Zehnder interferometry with edge-states wave packets

    Science.gov (United States)

    Beggi, Andrea; Bordone, Paolo; Buscemi, Fabrizio; Bertoni, Andrea

    2015-12-01

    We compute the exact single-particle time-resolved dynamics of electronic Mach-Zehnder interferometers based on Landau edge-states transport, and assess the effect of the spatial localization of carriers on the interference pattern. The exact carrier dynamics is obtained by solving numerically the time-dependent Schrödinger equation with a suitable 2D potential profile reproducing the interferometer design. An external magnetic field, driving the system to the quantum Hall regime with filling factor one, is included. The injected carriers are represented by a superposition of edge states, and their interference pattern—controlled via magnetic field and/or area variation—reproduces the one of (Ji et al 2003 Nature 422 415). By tuning the system towards different regimes, we find two additional features in the transmission spectra, both related to carrier localization, namely a damping of the Aharonov-Bohm oscillations with increasing difference in the arms length, and an increased mean transmission that we trace to the energy-dependent transmittance of quantum point contacts. Finally, we present an analytical model, also accounting for the finite spatial dispersion of the carriers, able to reproduce the above effects.

  10. Time-dependent simulation and analytical modelling of electronic Mach-Zehnder interferometry with edge-states wave packets.

    Science.gov (United States)

    Beggi, Andrea; Bordone, Paolo; Buscemi, Fabrizio; Bertoni, Andrea

    2015-12-01

    We compute the exact single-particle time-resolved dynamics of electronic Mach-Zehnder interferometers based on Landau edge-states transport, and assess the effect of the spatial localization of carriers on the interference pattern. The exact carrier dynamics is obtained by solving numerically the time-dependent Schrödinger equation with a suitable 2D potential profile reproducing the interferometer design. An external magnetic field, driving the system to the quantum Hall regime with filling factor one, is included. The injected carriers are represented by a superposition of edge states, and their interference pattern-controlled via magnetic field and/or area variation-reproduces the one of (Ji et al 2003 Nature 422 415). By tuning the system towards different regimes, we find two additional features in the transmission spectra, both related to carrier localization, namely a damping of the Aharonov-Bohm oscillations with increasing difference in the arms length, and an increased mean transmission that we trace to the energy-dependent transmittance of quantum point contacts. Finally, we present an analytical model, also accounting for the finite spatial dispersion of the carriers, able to reproduce the above effects. PMID:26548374

  11. Unifying interatomic potential, g (r), elasticity, viscosity, and fragility of metallic glasses: analytical model, simulations, and experiments

    Science.gov (United States)

    Lagogianni, A. E.; Krausser, J.; Evenson, Z.; Samwer, K.; Zaccone, A.

    2016-08-01

    An analytical framework is proposed to describe the elasticity, viscosity and fragility of metallic glasses in relation to their atomic-level structure and the effective interatomic interaction. The bottom-up approach starts with forming an effective Ashcroft–Born–Mayer interatomic potential based on Boltzmann inversion of the radial distribution function g (r) and on fitting the short-range part of g (r) by means of a simple power-law approximation. The power exponent λ represents a global repulsion steepness parameter. A scaling relation between atomic connectivity and packing fraction Z∼ {φ1+λ} is derived. This relation is then implemented in a lattice-dynamical model for the high-frequency shear modulus where the attractive anharmonic part of the effective interaction is taken into account through the thermal expansion coefficient which maps the ϕ-dependence into a T-dependence. The shear modulus as a function of temperature calculated in this way is then used within the cooperative shear model of the glass transition to yield the viscosity of the supercooled melt as a double-exponential function of T across the entire Angell plot. The model, which has only one adjustable parameter (the characteristic atomic volume for high-frequency cage deformation) is tested against new experimental data of ZrCu alloys and provides an excellent one-parameter description of the viscosity down to the glass transition temperature.

  12. A new closed-form analytical thermal model for simulating Stirling engines based on polytropic-finite speed thermodynamics

    International Nuclear Information System (INIS)

    Highlights: • A closed-form thermal model was presented for Stirling engines. • The new model was used to simulate the GPU-3 Stirling engine. • Results were compared with experimental data as well as other models. • The new model was more accurate and simple in calculation than other models. • Effects of the engines’ parameters on operation of engine were evaluated. - Abstract: Thermal models for the simulation of Stirling engines need to have greater accuracy along with simple and low-cost calculation. In this regard, a new closed-form thermal model was presented for the thermal simulation of Stirling engines. The new model called PFST (polytropic-finite speed thermodynamics) was developed based on the combination of polytropic analysis of expansion/compression processes and the concept of finite speed thermodynamics (FST). Therefore, compression/expansion works of compression/expansion processes and transferred heat into the heater of Stirling engines were determined based on polytropic analysis, instead of isothermal processes of the ideal Stirling cycle. The calculated work of polytropic processes was corrected to include the effects of internal irreversibilities including pressure throttling in heat exchangers, mechanical friction, and finite motion of the pistons. Output power and thermal efficiency of Stirling engines were calculated as functions of various engine parameters. The developed PFST model was implemented on a prototype Stirling engine, called GPU-3 engine, and the obtained results were compared with those of other closed-form and numerical models as well as experimental data. It was found that the new closed-form model, in addition to its simple and low-cost calculation, had the same order of accuracy as recently developed numerical models

  13. Prediction of the dynamic oscillation threshold of a clarinet model: Comparison between analytical predictions and simulation results

    CERN Document Server

    Bergeot, Baptiste; Vergez, Christophe; Gazengel, Bruno

    2014-01-01

    Simple models of clarinet instruments based on iterated maps have been used in the past to successfully estimate the threshold of oscillation of this instrument as a function of a constant blowing pressure. However, when the blowing pressure gradually increases through time, the oscillations appear at a much higher value than what is predicted in the static case. This is known as bifurcation delay, a phenomenon studied in [1] for a clarinet model. In numerical simulations the bifurcation delay showed a strong sensitivity to numerical precision.

  14. The New Numerical Galaxy Catalog (ν2GC): An updated semi-analytic model of galaxy and active galactic nucleus formation with large cosmological N-body simulations

    Science.gov (United States)

    Makiya, Ryu; Enoki, Motohiro; Ishiyama, Tomoaki; Kobayashi, Masakazu A. R.; Nagashima, Masahiro; Okamoto, Takashi; Okoshi, Katsuya; Oogi, Taira; Shirakata, Hikari

    2016-04-01

    We present a new cosmological galaxy formation model, ν2GC, as an updated version of our previous model νGC. We adopt the so-called "semi-analytic" approach, in which the formation history of dark matter halos is computed by N-body simulations, while the baryon physics such as gas cooling, star formation, and supernova feedback are simply modeled by phenomenological equations. Major updates of the model are as follows: (1) the merger trees of dark matter halos are constructed in state-of-the-art N-body simulations, (2) we introduce the formation and evolution process of supermassive black holes and the suppression of gas cooling due to active galactic nucleus (AGN) activity, (3) we include heating of the intergalactic gas by the cosmic UV background, and (4) we tune some free parameters related to the astrophysical processes using a Markov chain Monte Carlo method. Our N-body simulations of dark matter halos have unprecedented box size and mass resolution (the largest simulation contains 550 billion particles in a 1.12 Gpc h-1 box), enabling the study of much smaller and rarer objects. The model was tuned to fit the luminosity functions of local galaxies and mass function of neutral hydrogen. Local observations, such as the Tully-Fisher relation, the size-magnitude relation of spiral galaxies, and the scaling relation between the bulge mass and black hole mass were well reproduced by the model. Moreover, the model also reproduced well the cosmic star formation history and redshift evolution of rest-frame K-band luminosity functions. The numerical catalog of the simulated galaxies and AGNs is publicly available on the web.

  15. Neutron shielding calculations in a proton therapy facility based on Monte Carlo simulations and analytical models: Criterion for selecting the method of choice

    International Nuclear Information System (INIS)

    Proton therapy facilities are shielded to limit the amount of secondary radiation to which patients, occupational workers and members of the general public are exposed. The most commonly applied shielding design methods for proton therapy facilities comprise semi-empirical and analytical methods to estimate the neutron dose equivalent. This study compares the results of these methods with a detailed simulation of a proton therapy facility by using the Monte Carlo technique. A comparison of neutron dose equivalent values predicted by the various methods reveals the superior accuracy of the Monte Carlo predictions in locations where the calculations converge. However, the reliability of the overall shielding design increases if simulation results, for which solutions have not converged, e.g. owing to too few particle histories, can be excluded, and deterministic models are being used at these locations. Criteria to accept or reject Monte Carlo calculations in such complex structures are not well understood. An optimum rejection criterion would allow all converging solutions of Monte Carlo simulation to be taken into account, and reject all solutions with uncertainties larger than the design safety margins. In this study, the optimum rejection criterion of 10% was found. The mean ratio was 26, 62% of all receptor locations showed a ratio between 0.9 and 10, and 92% were between 1 and 100. (authors)

  16. Understanding the impact of recent advances in isoprene photooxidation on simulations of regional air quality

    OpenAIRE

    Xie, Y.; F. Paulot; W. P. L. Carter; C. G. Nolte; Luecken, D. J.; W. T. Hutzell; Wennberg, P. O.; Cohen, R. C.; Pinder, R. W.

    2013-01-01

    The CMAQ (Community Multiscale Air Quality) us model in combination with observations for INTEX-NA/ICARTT (Intercontinental Chemical Transport Experiment–North America/International Consortium for Atmospheric Research on Transport and Transformation) 2004 are used to evaluate recent advances in isoprene oxidation chemistry and provide constraints on isoprene nitrate yields, isoprene nitrate lifetimes, and NOx recycling rates. We incorporate recent advances in isoprene oxidation chemistry into...

  17. Understanding the impact of recent advances in isoprene photooxidation on simulations of regional air quality

    OpenAIRE

    Xie, Y.; W. P. L. Carter; C. G. Nolte; Luecken, D. J.; W. T. Hutzell; Wennberg, P. O.; Cohen, R. C.; Pinder, R. W.

    2013-01-01

    The CMAQ (Community Multiscale Air Quality) us model in combination with observations for INTEX-NA/ICARTT (Intercontinental Chemical Transport Experiment–North America/International Consortium for Atmospheric Research on Transport and Transformation) 2004 are used to evaluate recent advances in isoprene oxidation chemistry and provide constraints on isoprene nitrate yields, isoprene nitrate lifetimes, and NO_x recycling rates. We incorporate recent advances in isoprene oxidation chemistry int...

  18. Current status and future advancements in analytical post-factum detection of food irradiation within the EU and in global trade

    International Nuclear Information System (INIS)

    The paper summarizes and explains officially approved methods for reliable analytical detection of illegal or non-labelled treatment of foods with ionizing radiation, referring inter alia to a German study published in 1997. (orig./CB)

  19. Advances in HYDRA and its applications to simulations of inertial confinement fusion targets

    OpenAIRE

    Marinak M.M.; Kerbel G.D.; Koning J.M.; Patel M.V.; Sepke S.M.; McKinley M.S.; O'Brien M.J.; Procassini R.J.; Munro D.

    2013-01-01

    A new set of capabilities has been implemented in the HYDRA 2D/3D multiphysics inertial confinement fusion simulation code. These include a Monte Carlo particle transport library. It models transport of neutrons, gamma rays and light ions, as well as products they generate from nuclear and coulomb collisions. It allows accurate simulations of nuclear diagnostic signatures from capsule implosions. We apply it to here in a 3D simulation of a National Ignition Facility (NIF) ignition capsule whi...

  20. Development of Advanced Electrochemical Emission Spectroscopy for Monitoring Corrosion in Simulated DOE Liquid Waste

    Energy Technology Data Exchange (ETDEWEB)

    Digby D. Macdonald; Brian M. Marx; Sejin Ahn; Julio de Ruiz; Balaji Soundararaja; Morgan Smith; and Wendy Coulson

    2008-01-15

    Various forms of general and localized corrosion represent principal threats to the integrity of DOE liquid waste storage tanks. These tanks, which are of a single wall or double wall design, depending upon their age, are fabricated from welded carbon steel and contain a complex waste-form comprised of NaOH and NaNO{sub 3}, along with trace amounts of phosphate, sulfate, carbonate, and chloride. Because waste leakage can have a profound environmental impact, considerable interest exists in predicting the accumulation of corrosion damage, so as to more effectively schedule maintenance and repair. The different tasks that are being carried out under the current program are as follows: (1) Theoretical and experimental assessment of general corrosion of iron/steel in borate buffer solutions by using electrochemical impedance spectroscopy (EIS), ellipsometry and XPS techniques; (2) Development of a damage function analysis (DFA) which would help in predicting the accumulation of damage due to pitting corrosion in an environment prototypical of DOE liquid waste systems; (3) Experimental measurement of crack growth rate, acoustic emission signals and coupling currents for fracture in carbon and low alloy steels as functions of mechanical (stress intensity), chemical (conductivity), electrochemical (corrosion potential, ECP), and microstructural (grain size, precipitate size, etc) variables in a systematic manner, with particular attention being focused on the structure of the noise in the current and its correlation with the acoustic emissions; (4) Development of fracture mechanisms for carbon and low alloy steels that are consistent with the crack growth rate, coupling current data and acoustic emissions; (5) Inserting advanced crack growth rate models for SCC into existing deterministic codes for predicting the evolution of corrosion damage in DOE liquid waste storage tanks; (6) Computer simulation of the anodic and cathodic activity on the surface of the steel samples

  1. Accurately fitting advanced training. Flexible simulator training by modular training course concepts

    International Nuclear Information System (INIS)

    Every employee of a power plant contributes with his individual expertise to the success of the enterprise. Certainly personal skills of employees differ from each other as well as power plants are different. With respect to effective simulator training this means that no two simulator training courses can be identical. To exactly meet the requirements of our customers KWS has developed modules for simulation training courses. Each module represents either a technical subject or addresses a topic in the field of soft skills. An accurately fitting combination of several of these modules to the needs of our customers allows for most efficient simulator training courses. (orig.)

  2. Advances in HYDRA and its applications to simulations of inertial confinement fusion targets

    Directory of Open Access Journals (Sweden)

    Marinak M.M.

    2013-11-01

    Full Text Available A new set of capabilities has been implemented in the HYDRA 2D/3D multiphysics inertial confinement fusion simulation code. These include a Monte Carlo particle transport library. It models transport of neutrons, gamma rays and light ions, as well as products they generate from nuclear and coulomb collisions. It allows accurate simulations of nuclear diagnostic signatures from capsule implosions. We apply it to here in a 3D simulation of a National Ignition Facility (NIF ignition capsule which models the full capsule solid angle. This simulation contains a severely rough ablator perturbation and provides diagnostics signatures of capsule failure due to excessive instability growth.

  3. Advances in HYDRA and its applications to simulations of inertial confinement fusion targets

    International Nuclear Information System (INIS)

    A new set of capabilities has been implemented in the HYDRA 2D/3D multiphysics inertial confinement fusion simulation code. These include a Monte Carlo particle transport library. It models transport of neutrons, gamma rays and light ions, as well as products they generate from nuclear and coulomb collisions. It allows accurate simulations of nuclear diagnostic signatures from capsule implosions. We apply it to here in a 3D simulation of a National Ignition Facility (NIF) ignition capsule which models the full capsule solid angle. This simulation contains a severely rough ablator perturbation and provides diagnostics signatures of capsule failure due to excessive instability growth. (authors)

  4. Simplified analytical model to simulate radionuclide release from radioactive waste trenches; Modelo simplificado para simulacao da liberacao de radionuclideos de repositorios de rejeitos radioativos

    Energy Technology Data Exchange (ETDEWEB)

    Sa, Bernardete Lemes Vieira de

    2001-07-01

    In order to evaluate postclosure off-site doses from low-level radioactive waste disposal facilities, a computer code was developed to simulate the radionuclide released from waste form, transport through vadose zone and transport in the saturated zone. This paper describes the methodology used to model these process. The radionuclide released from the waste is calculated using a model based on first order kinetics and the transport through porous media was determined using semi-analytical solution of the mass transport equation, considering the limiting case of unidirectional convective transport with three-dimensional dispersion in an isotropic medium. The results obtained in this work were compared with other codes, showing good agreement. (author)

  5. An improved analytical model for CT dose simulation with a new look at the theory of CT dose

    International Nuclear Information System (INIS)

    Gagne [Med. Phys. 16, 29-37 (1989)] has previously described a model for predicting the sensitivity and dose profiles in the slice-width (z) direction for CT scanners. The model, developed prior to the advent of multidetector CT scanners, is still widely used; however, it does not account for the effect of anode tilt on the penumbra or include the heel effect, both of which are increasingly important for the wider beams (up to 40 mm) of contemporary, multidetector scanners. Additionally, it applied only on (or near) the axis of rotation, and did not incorporate the photon energy spectrum. The improved model described herein transcends all of the aforementioned limitations of the Gagne model, including extension to the peripheral phantom axes. Comparison of simulated and measured dose data provides experimental validation of the model, including verification of the superior match to the penumbra provided by the tilted-anode model, as well as the observable effects on the cumulative dose distribution. The initial motivation for the model was to simulate the quasiperiodic dose distribution on the peripheral, phantom axes resulting from a helical scan series in order to facilitate the implementation of an improved method of CT dose measurement utilizing a short ion chamber, as proposed by Dixon [Med. Phys. 30, 1272-1280 (2003)]. A more detailed set of guidelines for implementing such measurements is also presented in this paper. In addition, some fundamental principles governing CT dose which have not previously been clearly enunciated follow from the model, and a fundamental (energy-based) quantity dubbed 'CTDI-aperture' is introduced

  6. Advanced Techniques for Reservoir Simulation and Modeling of Non-Conventional Wells; FINAL

    International Nuclear Information System (INIS)

    Research results for the second year of this project on the development of improved modeling techniques for non-conventional (e.g., horizontal, deviated or multilateral) wells were presented. The overall program entails the development of enhanced well modeling and general simulation capabilities. A general formulation for black-oil and compositional reservoir simulation was presented

  7. Advanced Techniques for Reservoir Simulation and Modeling of Non-Conventional Wells

    Energy Technology Data Exchange (ETDEWEB)

    Durlofsky, Louis J.; Aziz, Khalid

    2001-08-23

    Research results for the second year of this project on the development of improved modeling techniques for non-conventional (e.g., horizontal, deviated or multilateral) wells were presented. The overall program entails the development of enhanced well modeling and general simulation capabilities. A general formulation for black-oil and compositional reservoir simulation was presented.

  8. 分析动力学三个问题的研究进展%ADVANCES IN THREE PROBLEMS OF ANALYTICAL DYNAMICS

    Institute of Scientific and Technical Information of China (English)

    梅凤翔; 吴惠彬

    2014-01-01

    The development of analytical mechanics involves many aspects of theory and application.This paper summarizes the recent progress of analytical mechanics in three problems on the interdisciplinarity between analyt-ical mechanics and mathematics.The first is to study the integration problem of equations of analytical dynamics by using some results of Lie groups and Lie algebras.The second is to apply the classical and modern integration methods of analytical mechanics to the integration problem of general differential equations.The third is to trans-form the equations of analytical dynamics into the equations of gradient system under certain conditions and then discuss the dynamical behaviors of the mechanical system by using the properties of gradient system.%分析力学的发展涉及理论的和应用的诸多方面。本文在分析力学与数学交缘的三个问题上综述分析力学的近代发展。第一是利用Lie群和Lie代数的一些成果来研究分析动力学方程的积分问题。第二是将分析力学的经典和近代积分方法应用于一般微分方程的积分问题。第三是将分析动力学方程在一定条件下化成梯度系统的方程,再用梯度系统的性质来研究力学系统的动力学行为。

  9. Brain-wave measures of workload in advanced cockpits: The transition of technology from laboratory to cockpit simulator, phase 2

    Science.gov (United States)

    Horst, Richard L.; Mahaffey, David L.; Munson, Robert C.

    1989-01-01

    The present Phase 2 small business innovation research study was designed to address issues related to scalp-recorded event-related potential (ERP) indices of mental workload and to transition this technology from the laboratory to cockpit simulator environments for use as a systems engineering tool. The project involved five main tasks: (1) Two laboratory studies confirmed the generality of the ERP indices of workload obtained in the Phase 1 study and revealed two additional ERP components related to workload. (2) A task analysis' of flight scenarios and pilot tasks in the Advanced Concepts Flight Simulator (ACFS) defined cockpit events (i.e., displays, messages, alarms) that would be expected to elicit ERPs related to workload. (3) Software was developed to support ERP data analysis. An existing ARD-proprietary package of ERP data analysis routines was upgraded, new graphics routines were developed to enhance interactive data analysis, and routines were developed to compare alternative single-trial analysis techniques using simulated ERP data. (4) Working in conjunction with NASA Langley research scientists and simulator engineers, preparations were made for an ACFS validation study of ERP measures of workload. (5) A design specification was developed for a general purpose, computerized, workload assessment system that can function in simulators such as the ACFS.

  10. A Visual Basic simulation software tool for performance analysis of a membrane-based advanced water treatment plant.

    Science.gov (United States)

    Pal, P; Kumar, R; Srivastava, N; Chowdhury, J

    2014-02-01

    A Visual Basic simulation software (WATTPPA) has been developed to analyse the performance of an advanced wastewater treatment plant. This user-friendly and menu-driven software is based on the dynamic mathematical model for an industrial wastewater treatment scheme that integrates chemical, biological and membrane-based unit operations. The software-predicted results corroborate very well with the experimental findings as indicated in the overall correlation coefficient of the order of 0.99. The software permits pre-analysis and manipulation of input data, helps in optimization and exhibits performance of an integrated plant visually on a graphical platform. It allows quick performance analysis of the whole system as well as the individual units. The software first of its kind in its domain and in the well-known Microsoft Excel environment is likely to be very useful in successful design, optimization and operation of an advanced hybrid treatment plant for hazardous wastewater. PMID:23982824

  11. Simulation Augmented Manoeuvring Design and Monitoring - a New Method for Advanced Ship Handling

    Directory of Open Access Journals (Sweden)

    Knud Benedict

    2014-03-01

    Full Text Available A fast time simulation tool box is under development to simulate the ships motion with complex dynamic models and to display the ships track immediately for the intended or actual rudder or engine manoeuvre. Based on this approach the innovative Simulation Augmented Manoeuvring Design and Monitoring - SAMMON tool box will allow for (a a new type of design of a manoeuvring plan as enhancement exceeding the common pure way point planning (b an unmatched monitoring of ship handling processes to follow the underlying manoeuvring plan. During the manoeuvring process the planned manoeuvres can be constantly displayed together with the actual ship motion and the predicted future track which is based on actual input data from the ship's sensors and manoeuvring handle positions. This SAMMON tool box is intended be used on board of real ships but it is in parallel an effective tool for training in ship handling simulators: (a in the briefing for preparing a manoeuvring plan for the whole exercise in some minutes, (b during the exercise run to see the consequences of the use of manoeuvring equipment even before the ship has changed her motion and (c in debriefing sessions to discuss potential alternatives of the students decisions by simulating fast variations of their choices during the exercises. Examples will be given for results from test trials on board and in the full mission ship handling simulator of the Maritime Simulation Centre Warnemuende.

  12. Analytic trigonometry

    CERN Document Server

    Bruce, William J; Maxwell, E A; Sneddon, I N

    1963-01-01

    Analytic Trigonometry details the fundamental concepts and underlying principle of analytic geometry. The title aims to address the shortcomings in the instruction of trigonometry by considering basic theories of learning and pedagogy. The text first covers the essential elements from elementary algebra, plane geometry, and analytic geometry. Next, the selection tackles the trigonometric functions of angles in general, basic identities, and solutions of equations. The text also deals with the trigonometric functions of real numbers. The fifth chapter details the inverse trigonometric functions

  13. TNO ADVANCE: a modular simulation tool for combined chassis and powertrain analysis

    NARCIS (Netherlands)

    Tillaart, E. van den; Mourad, S.; Lupker, H.

    2001-01-01

    In this paper TNO-Advance is presented. It is built in a modular way, therefore allowing quick assembling of specific vehicle configurations and easy integration of new component models and future evolutions of existing models. Its entensive library is built in Matlab/Simulink, taking advantage of i

  14. Recent advances in gyrokinetic full-f particle simulation of medium sized Tokamaks with ELMFIRE

    International Nuclear Information System (INIS)

    Large-scale kinetic simulations of toroidal plasmas based on first principles are called for in studies of transition from low to high confinement mode and internal transport barrier formation in the core plasma. Such processes are best observed and diagnosed in detached plasma conditions in mid-sized tokamaks, so gyrokinetic simulations for these conditions are warranted. A first principles test-particle based kinetic model ELMFIRE[1] has been developed and used in interpretation[1,2] of FT-2 and DIII-D experiments. In this work we summarize progress in Cyclone (DIII-D core) and ASDEX Upgrade pedestal region simulations, and show that in simulations the choice of adiabatic electrons results in quenching of turbulence (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. Recent advances in gyrokinetic full-f particle simulation of medium sized Tokamaks with ELMFIRE

    Energy Technology Data Exchange (ETDEWEB)

    Janhunen, S.J.; Kiviniemi, T.P.; Korpio, T.; Leerink, S.; Nora, M. [Helsinki University of Technology, Euratom-Tekes Association, Espoo (Finland); Heikkinen, J.A. [VTT, Euratom-Tekes Association, Espoo (Finland); Ogando, F. [Helsinki University of Technology, Euratom-Tekes Association, Espoo (Finland); Universidad Nacional de Educacion a Distancia, Madrid (Spain)

    2010-05-15

    Large-scale kinetic simulations of toroidal plasmas based on first principles are called for in studies of transition from low to high confinement mode and internal transport barrier formation in the core plasma. Such processes are best observed and diagnosed in detached plasma conditions in mid-sized tokamaks, so gyrokinetic simulations for these conditions are warranted. A first principles test-particle based kinetic model ELMFIRE[1] has been developed and used in interpretation[1,2] of FT-2 and DIII-D experiments. In this work we summarize progress in Cyclone (DIII-D core) and ASDEX Upgrade pedestal region simulations, and show that in simulations the choice of adiabatic electrons results in quenching of turbulence (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  16. Advances in simulated modeling of vibration systems based on computational intelligence

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Computational intelligence is the computational simulation of the bio-intelligence, which includes artificial neural networks, fuzzy systems and evolutionary computations. This article summarizes the state of the art in the field of simulated modeling of vibration systems using methods of computational intelligence, based on some relevant subjects and the authors' own research work. First, contributions to the applications of computational intelligence to the identification of nonlinear characteristics of packaging are reviewed. Subsequently, applications of the newly developed training algorithms for feedforward neural networks to the identification of restoring forces in multi-degree-of-freedom nonlinear systems are discussed. Finally, the neural-network-based method of model reduction for the dynamic simulation of microelectromechanical systems (MEMS) using generalized Hebbian algorithm (GHA) and robust GHA is outlined. The prospects of the simulated modeling of vibration systems using techniques of computational intelligence are also indicated.

  17. Akuna - Integrated Toolsets Supporting Advanced Subsurface Flow and Transport Simulations for Environmental Management

    Energy Technology Data Exchange (ETDEWEB)

    Schuchardt, Karen L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Agarwal, Deborah A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Finsterle, Stefan A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gable, Carl W. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gorton, Ian [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gosink, Luke J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Keating, Elizabeth H. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lansing, Carina S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Meyer, Joerg [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Moeglein, William A.M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pau, George S.H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Porter, Ellen A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Purohit, Sumit [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rockhold, Mark L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Shoshani, Arie [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sivaramakrishnan, Chandrika [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2012-04-24

    A next generation open source subsurface simulator and user environment for environmental management is being developed through a collaborative effort across Department of Energy National Laboratories. The flow and transport simulator, Amanzi, will be capable of modeling complex subsurface environments and processes using both unstructured and adaptive meshes at very fine spatial resolutions that require supercomputing-scale resources. The user environment, Akuna, provides users with a range of tools to manage environmental and simulator data sets, create models, manage and share simulation data, and visualize results. Underlying the user interface are core toolsets that provide algorithms for sensitivity analysis, parameter estimation, and uncertainty quantification. Akuna is open-source, cross platform software that is initially being demonstrated on the Hanford BC Cribs remediation site. In this paper, we describe the emerging capabilities of Akuna and illustrate how these are being applied to the BC Cribs site.

  18. A predictive analytic model for high-performance tunneling field-effect transistors approaching non-equilibrium Green's function simulations

    International Nuclear Information System (INIS)

    A new compact modeling approach is presented which describes the full current-voltage (I-V) characteristic of high-performance (aggressively scaled-down) tunneling field-effect-transistors (TFETs) based on homojunction direct-bandgap semiconductors. The model is based on an analytic description of two key features, which capture the main physical phenomena related to TFETs: (1) the potential profile from source to channel and (2) the elliptic curvature of the complex bands in the bandgap region. It is proposed to use 1D Poisson's equations in the source and the channel to describe the potential profile in homojunction TFETs. This allows to quantify the impact of source/drain doping on device performance, an aspect usually ignored in TFET modeling but highly relevant in ultra-scaled devices. The compact model is validated by comparison with state-of-the-art quantum transport simulations using a 3D full band atomistic approach based on non-equilibrium Green's functions. It is shown that the model reproduces with good accuracy the data obtained from the simulations in all regions of operation: the on/off states and the n/p branches of conduction. This approach allows calculation of energy-dependent band-to-band tunneling currents in TFETs, a feature that allows gaining deep insights into the underlying device physics. The simplicity and accuracy of the approach provide a powerful tool to explore in a quantitatively manner how a wide variety of parameters (material-, size-, and/or geometry-dependent) impact the TFET performance under any bias conditions. The proposed model presents thus a practical complement to computationally expensive simulations such as the 3D NEGF approach

  19. A predictive analytic model for high-performance tunneling field-effect transistors approaching non-equilibrium Green's function simulations

    Energy Technology Data Exchange (ETDEWEB)

    Salazar, Ramon B., E-mail: ramon@purdue.edu, E-mail: hilatikh@purdue.edu; Appenzeller, Joerg [Birck Nanotechnology Center, Purdue University, 1205 W. State Street, West Lafayette, Indiana 47907 (United States); Ilatikhameneh, Hesameddin, E-mail: ramon@purdue.edu, E-mail: hilatikh@purdue.edu; Rahman, Rajib; Klimeck, Gerhard [Network for Computational Nanotechnology, 207 S. Martin Jischke Drive, West Lafayette, Indiana 47907 (United States)

    2015-10-28

    A new compact modeling approach is presented which describes the full current-voltage (I-V) characteristic of high-performance (aggressively scaled-down) tunneling field-effect-transistors (TFETs) based on homojunction direct-bandgap semiconductors. The model is based on an analytic description of two key features, which capture the main physical phenomena related to TFETs: (1) the potential profile from source to channel and (2) the elliptic curvature of the complex bands in the bandgap region. It is proposed to use 1D Poisson's equations in the source and the channel to describe the potential profile in homojunction TFETs. This allows to quantify the impact of source/drain doping on device performance, an aspect usually ignored in TFET modeling but highly relevant in ultra-scaled devices. The compact model is validated by comparison with state-of-the-art quantum transport simulations using a 3D full band atomistic approach based on non-equilibrium Green's functions. It is shown that the model reproduces with good accuracy the data obtained from the simulations in all regions of operation: the on/off states and the n/p branches of conduction. This approach allows calculation of energy-dependent band-to-band tunneling currents in TFETs, a feature that allows gaining deep insights into the underlying device physics. The simplicity and accuracy of the approach provide a powerful tool to explore in a quantitatively manner how a wide variety of parameters (material-, size-, and/or geometry-dependent) impact the TFET performance under any bias conditions. The proposed model presents thus a practical complement to computationally expensive simulations such as the 3D NEGF approach.

  20. CORBA and MPI-based 'backbone' for coupling advanced simulation tools

    International Nuclear Information System (INIS)

    There is a growing international interest in using coupled, multidisciplinary computer simulations for a variety of purposes, including nuclear reactor safety analysis. Reactor behaviour can be modeled using a suite of computer programs simulating phenomena or predicting parameters that can be categorized into disciplines such as Thermalhydraulics, Neutronics, Fuel, Fuel Channels, Fission Product Release and Transport, Containment and Atmospheric Dispersion, and Severe Accident Analysis. Traditionally, simulations used for safety analysis individually addressed only the behaviour within a single discipline, based upon static input data from other simulation programs. The limitation of using a suite of stand-alone simulations is that phenomenological interdependencies or temporal feedback between the parameters calculated within individual simulations cannot be adequately captured. To remove this shortcoming, multiple computer simulations for different disciplines must exchange data during runtime to address these interdependencies. This article describes the concept of a new framework, which we refer to as the 'Backbone', to provide the necessary runtime exchange of data. The Backbone, currently under development at AECL for a preliminary feasibility study, is a hybrid design using features taken from the Common Object Request Broker Architecture (CORBA), a standard defined by the Object Management Group, and the Message Passing Interface (MPI), a standard developed by a group of researchers from academia and industry. Both have well-tested and efficient implementations, including some that are freely available under the GNU public licenses. The CORBA component enables individual programs written in different languages and running on different platforms within a network to exchange data with each other, thus behaving like a single application. MPI provides the process-to-process intercommunication between these programs. This paper outlines the different CORBA and

  1. A study on optimization of hybrid drive train using Advanced Vehicle Simulator (ADVISOR)

    Science.gov (United States)

    Same, Adam; Stipe, Alex; Grossman, David; Park, Jae Wan

    This study investigates the advantages and disadvantages of three hybrid drive train configurations: series, parallel, and "through-the-ground" parallel. Power flow simulations are conducted with the MATLAB/Simulink-based software ADVISOR. These simulations are then applied in an application for the UC Davis SAE Formula Hybrid vehicle. ADVISOR performs simulation calculations for vehicle position using a combined backward/forward method. These simulations are used to study how efficiency and agility are affected by the motor, fuel converter, and hybrid configuration. Three different vehicle models are developed to optimize the drive train of a vehicle for three stages of the SAE Formula Hybrid competition: autocross, endurance, and acceleration. Input cycles are created based on rough estimates of track geometry. The output from these ADVISOR simulations is a series of plots of velocity profile and energy storage State of Charge that provide a good estimate of how the Formula Hybrid vehicle will perform on the given course. The most noticeable discrepancy between the input cycle and the actual velocity profile of the vehicle occurs during deceleration. A weighted ranking system is developed to organize the simulation results and to determine the best drive train configuration for the Formula Hybrid vehicle. Results show that the through-the-ground parallel configuration with front-mounted motors achieves an optimal balance of efficiency, simplicity, and cost. ADVISOR is proven to be a useful tool for vehicle power train design for the SAE Formula Hybrid competition. This vehicle model based on ADVISOR simulation is applicable to various studies concerning performance and efficiency of hybrid drive trains.

  2. Advanced Variance Reduction for Global k-Eigenvalue Simulations in MCNP

    International Nuclear Information System (INIS)

    between fission source estimates. In the new FMC method, the eigenvalue problem (expressed in terms of the Boltzmann equation) is integrated over the energy and direction variables. Then these equations are multiplied by J special 'tent' functions in space and integrated over the spatial variable. This yields J equations that are exactly satisfied by the eigenvalue k and J space-angle-energy moments of the eigenfunction. Multiplying and dividing by suitable integrals of the eigenfunction, one obtains J algebraic equations for k and the space-angle-energy moments of the eigenfunction, which contain nonlinear functionals that depend weakly on the eigenfunction. In the FMC method, information from the standard Monte Carlo solution for each active cycle is used to estimate the functionals, and at the end of each cycle the J equations for k and the space-angle-energy moments of the eigenfunction are solved. Finally, these results are averaged over N active cycles to obtain estimated means and standard deviations for k and the space-angle-energy moments of the eigenfunction. Our limited testing shows that for large single fissile systems such as a commercial reactor core, (i) the FMC estimate of the eigenvalue is at least one order of magnitude more accurate than estimates obtained from the standard Monte Carlo approach, (ii) the FMC estimate of the eigenfunction converges and is several orders of magnitude more accurate than the standard estimate, and (iii) the FMC estimate of the standard deviation in k is at least one order of magnitude closer to the correct standard deviation than the standard estimate. These advances occur because: (i) the Monte Carlo estimates of the nonlinear functionals are much more accurate than the direct Monte Carlo estimates of the eigenfunction, (ii) the system of discrete equations that determines the FMC estimates of k is robust, and (iii) the functionals are only very weakly correlated between different fission generations. The FMC method was

  3. Advanced CFD simulations of turbulent flows around appendages in CANDU fuel bundles

    International Nuclear Information System (INIS)

    Computational Fluid Dynamics (CFD) was used to simulate the coolant flow in a modified 37-element CANDU fuel bundle, in order to investigate the effects of the appendages on the flow field. First, a subchannel model was created to qualitatively analyze the capabilities of different turbulence models such as k.ε, Reynolds Normalization Group (RNG), Shear Stress Transport (SST) and Large Eddy Simulation (LES). Then, the turbulence model with the acceptable quality was used to investigate the effects of positioning appendages, normally used in CANDU 37-element Critical Heat Flux (CHF) experiments, on the flow field. It was concluded that the RNG and SST models both show improvements over the k.ε method by predicting cross flow rates closer to those predicted by the LES model. Also the turbulence effects in the k.ε model dissipate quickly downstream of the appendages, while in the RNG and SST models appear at longer distances similar to the LES model. The RNG method simulation time was relatively feasible and as a result was chosen for the bundle model simulations. In the bundle model simulations it was shown that the tunnel spacers and leaf springs, used to position the bundles inside the pressure tubes in the experiments, have no measureable dominant effects on the flow field. The flow disturbances are localized and disappear at relatively short streamwise distances. (author)

  4. SciDAC Advances in Beam Dynamics Simulation: From Light Sources to Colliders

    International Nuclear Information System (INIS)

    In this paper, we report on progress that has been made in beam dynamics simulation, from light sources to colliders, during the first year of the SciDAC-2 accelerator project 'Community Petascale Project for Accelerator Science and Simulation (ComPASS).' Several parallel computational tools for beam dynamics simulation are described. Also presented are number of applications in current and future accelerator facilities (e.g., LCLS, RHIC, Tevatron, LHC, and ELIC). Particle accelerators are some of most important tools of scientific discovery. They are widely used in high-energy physics, nuclear physics, and other basic and applied sciences to study the interaction of elementary particles, to probe the internal structure of matter, and to generate high-brightness radiation for research in materials science, chemistry, biology, and other fields. Modern accelerators are complex and expensive devices that may be several kilometers long and may consist of thousands of beamline elements. An accelerator may transport trillions of charged particles that interact electromagnetically among themselves, that interact with fields produced by the accelerator components, and that interact with beam-induced fields. Large-scale beam dynamics simulations on massively parallel computers can help provide understanding of these complex physical phenomena, help minimize design cost, and help optimize machine operation. In this paper, we report on beam dynamics simulations in a variety of accelerators ranging from next generation light sources to high-energy ring colliders that have been studied during the first year of the SciDAC-2 accelerator project.

  5. Numerical models for the simulation of the cyclic behaviour of RC structures incorporating new advanced materials

    OpenAIRE

    Varma, Rajendra Kumar

    2013-01-01

    Tese de doutoramento em Estrutural Engenharia This work deals with material modelling and numerical implementation for nonlinear finite element analysis of reinforced concrete (RC) structures. Since the behaviour of concrete and steel being crucial for any RC structure under loading, uniaxial cyclic constitutive models for both were implemented in FEMIX, finite element software. Various advanced materials have been developed with specific purposes, like fibre reinforced c...

  6. Investigation of advanced strain-path dependent material models for sheet metal forming simulations

    OpenAIRE

    Haddag, Badis; BALAN, Tudor; ABED-MERAIM, Farid

    2006-01-01

    Sheet metal forming processes often involve complex loading sequences. To improve the prediction of some undesirable phenomena, such as springback, physical behavior models should be considered. This paper investigates springback behavior predicted by advanced elastoplastic hardening models which combine isotropic and kinematic hardening and take strain-path changes into account. A dislocation-based microstructural hardening model formulated from physical observations and the more classical c...

  7. Quantifying the Effect of Fast Charger Deployments on Electric Vehicle Utility and Travel Patterns via Advanced Simulation: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Wood, E.; Neubauer, J.; Burton, E.

    2015-02-01

    The disparate characteristics between conventional (CVs) and battery electric vehicles (BEVs) in terms of driving range, refill/recharge time, and availability of refuel/recharge infrastructure inherently limit the relative utility of BEVs when benchmarked against traditional driver travel patterns. However, given a high penetration of high-power public charging combined with driver tolerance for rerouting travel to facilitate charging on long-distance trips, the difference in utility between CVs and BEVs could be marginalized. We quantify the relationships between BEV utility, the deployment of fast chargers, and driver tolerance for rerouting travel and extending travel durations by simulating BEVs operated over real-world travel patterns using the National Renewable Energy Laboratory's Battery Lifetime Analysis and Simulation Tool for Vehicles (BLAST-V). With support from the U.S. Department of Energy's Vehicle Technologies Office, BLAST-V has been developed to include algorithms for estimating the available range of BEVs prior to the start of trips, for rerouting baseline travel to utilize public charging infrastructure when necessary, and for making driver travel decisions for those trips in the presence of available public charging infrastructure, all while conducting advanced vehicle simulations that account for battery electrical, thermal, and degradation response. Results from BLAST-V simulations on vehicle utility, frequency of inserted stops, duration of charging events, and additional time and distance necessary for rerouting travel are presented to illustrate how BEV utility and travel patterns can be affected by various fast charge deployments.

  8. Advanced methods in global gyrokinetic full f particle simulation of tokamak transport

    International Nuclear Information System (INIS)

    A new full f nonlinear gyrokinetic simulation code, named ELMFIRE, has been developed for simulating transport phenomena in tokamak plasmas. The code is based on a gyrokinetic particle-in-cell algorithm, which can consider electrons and ions jointly or separately, as well as arbitrary impurities. The implicit treatment of the ion polarization drift and the use of full f methods allow for simulations of strongly perturbed plasmas including wide orbit effects, steep gradients and rapid dynamic changes. This article presents in more detail the algorithms incorporated into ELMFIRE, as well as benchmarking comparisons to both neoclassical theory and other codes.Code ELMFIRE calculates plasma dynamics by following the evolution of a number of sample particles. Because of using an stochastic algorithm its results are influenced by statistical noise. The effect of noise on relevant magnitudes is analyzed.Turbulence spectra of FT-2 plasma has been calculated with ELMFIRE, obtaining results consistent with experimental data

  9. Validation of advanced NSSS simulator model for loss-of-coolant accidents

    Energy Technology Data Exchange (ETDEWEB)

    Kao, S.P.; Chang, S.K.; Huang, H.C. [Nuclear Training Branch, Northeast Utilities, Waterford, CT (United States)

    1995-09-01

    The replacement of the NSSS (Nuclear Steam Supply System) model on the Millstone 2 full-scope simulator has significantly increased its fidelity to simulate adverse conditions in the RCS. The new simulator NSSS model is a real-time derivative of the Nuclear Plant Analyzer by ABB. The thermal-hydraulic model is a five-equation, non-homogeneous model for water, steam, and non-condensible gases. The neutronic model is a three-dimensional nodal diffusion model. In order to certify the new NSSS model for operator training, an extensive validation effort has been performed by benchmarking the model performance against RELAP5/MOD2. This paper presents the validation results for the cases of small-and large-break loss-of-coolant accidents (LOCA). Detailed comparisons in the phenomena of reflux-condensation, phase separation, and two-phase natural circulation are discussed.

  10. Markov chains analytic and Monte Carlo computations

    CERN Document Server

    Graham, Carl

    2014-01-01

    Markov Chains: Analytic and Monte Carlo Computations introduces the main notions related to Markov chains and provides explanations on how to characterize, simulate, and recognize them. Starting with basic notions, this book leads progressively to advanced and recent topics in the field, allowing the reader to master the main aspects of the classical theory. This book also features: Numerous exercises with solutions as well as extended case studies.A detailed and rigorous presentation of Markov chains with discrete time and state space.An appendix presenting probabilistic notions that are nec

  11. Simulation of Electric Faults in Doubly-Fed Induction Generators Employing Advanced Mathematical Modelling

    DEFF Research Database (Denmark)

    Martens, Sebastian; Mijatovic, Nenad; Holbøll, Joachim;

    2015-01-01

    many areas of electrical machine analysis. However, for fault investigations, the phase-coordinate representation has been found more suitable. This paper presents a mathematical model in phase coordinates of the DFIG with two parallel windings per rotor phase. The model has been implemented in Matlab...... and its properties in context of fault simulations and investigations has been investigated. Some of the most common faults have been simulated, namely broken rotor bars or windings, dynamic eccentricities and stator phase winding short circuits. These fault conditions propagate to the stator current...

  12. A review of recent advances in numerical simulations of microscale fuel processor for hydrogen production

    Science.gov (United States)

    Holladay, J. D.; Wang, Y.

    2015-05-01

    Microscale (methanol as the fuel due to methanol's low reforming temperature and high conversion, although, there are several methane fueled systems. The increased computational power and more complex codes have led to improved accuracy of numerical simulations. Initial models focused on the reformer, while more recently, the simulations began including other unit operations such as vaporizers, inlet manifolds, and combustors. These codes are critical for developing the next generation systems. The systems reviewed included plate reactors, microchannel reactors, and annulus reactors for both wash-coated and packed bed systems.

  13. Material properties of low pressure chemical vapor deposited silicon nitride for modeling and calibrating the simulation of advanced isolation structures

    Science.gov (United States)

    Smeys, Peter I. L.; Griffin, Peter B.; Saraswat, Krishna C.

    1995-08-01

    The increasing cost and complexity of semiconductor process development has lead to the widespread use of multidimensional semiconductor process simulators. The success of a program like SUPREM-IV is primarily due to the fact that it is based on physical models, rather than empirical equations. This is in contrast to the first generation of process simulators, which calculated impurity profiles and oxide thickness in one dimension based on semiempirical approaches. SUPREM-IV incorporates two-dimensional coupled stress-dependent oxidation and impurity diffusion, which allows the accurate simulations of state-of-the-art integrated processes, provided that accurate model parameter sets are available. In this article we present an improved calibration methodology for simulation of advanced isolation technologies using SUPREM-IV, based on the experimental determination of the material properties of silicon nitride. The proposed strategy is applicable not only to SUPREM-IV but to any numerical simulator that uses the stress-dependent oxidation models to calculate oxide growth. In order to simulate experimental isolation boundary shapes, the oxidation models in SUPREM-IV must be calibrated. This requires a set of five fitting parameters, i.e., the material viscosities and activation volumes for stress-dependent diffusion, reaction rate, and critical stress. These parameters form a quintuplet but are not unique. Multiplying the viscosity values and dividing the activation volumes by a constant will yield exactly the same isolation structure boundary shape. The calculated stresses in the substrate however do not remain constant when different quintuplets are used. This has serious implications since isolation structures require the stress levels in the silicon substrate to remain well below the yield stress of silicon. If a nonoptimal parameter set is used, incorrect designs will result. Based on the experimental extraction of the silicon nitride viscosity by measuring the

  14. CFD simulations of moderator flow inside Calandria of the Passive Moderator Cooling System of an advanced reactor

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Eshita [Homi Bhabha National Institute, Anushaktinagar, Mumbai 400 094 (India); Kumar, Mukesh [Reactor Engineering Division, Bhabha Atomic Research Center, Trombay, Mumbai 400 085 (India); Joshi, Jyeshtharaj B., E-mail: jbjoshi@gmail.com [Homi Bhabha National Institute, Anushaktinagar, Mumbai 400 094 (India); Department of Chemical Engineering, Institute of Chemical Technology, Matunga, Mumbai 400019 India (India); Nayak, Arun K. [Reactor Engineering Division, Bhabha Atomic Research Center, Trombay, Mumbai 400 085 (India); Vijayan, Pallippattu K., E-mail: vijayanp@barc.gov.in [Reactor Engineering Division, Bhabha Atomic Research Center, Trombay, Mumbai 400 085 (India)

    2015-10-15

    Highlights: • CFD simulations in the Calandria of an advanced reactor under natural circulation. • Under natural convection, majority of the flow recirculates within the Calandria. • Maximum temperature is located at the top and center of the fuel channel matrix. • During SBO, temperature inside Calandria is stratified. - Abstract: Passive systems are being examined for the future Advanced Nuclear Reactor designs. One of such concepts is the Passive Moderator Cooling System (PMCS), which is designed to remove heat from the moderator in the Calandria vessel passively in case of an extended Station Black Out condition. The heated heavy-water moderator (due to heat transferred from the Main Heat Transport System (MHTS) and thermalization of neutrons and gamma from radioactive decay of fuel) rises upward due to buoyancy, gets cooled down in a heat exchanger and returns back to Calandria, completing a natural circulation loop. The natural circulation should provide sufficient cooling to prevent the increase of moderator temperature and pressure beyond safe limits. In an earlier study, a full-scale 1D transient simulation was performed for the reactor including the MHTS and the PMCS, in the event of a station blackout scenario (Kumar et al., 2013). The results indicate that the systems remain within the safe limits for 7 days. However, the flow inside a geometry like Calandria is quite complex due to its large size and inner complexities of dense fuel channel matrix, which was simplified as a 1D pipe flow in the aforesaid analysis. In the current work, CFD simulations are performed to study the temperature distributions and flow distribution of moderator inside the Calandria vessel using a three-dimensional CFD code, OpenFoam 2.2.0. First, a set of steady state simulation was carried out for a band of inlet mass flow rates, which gives the minimum mass flow rate required for removing the maximum heat load, by virtue of prediction of hot spots inside the Calandria

  15. CFD simulations of moderator flow inside Calandria of the Passive Moderator Cooling System of an advanced reactor

    International Nuclear Information System (INIS)

    Highlights: • CFD simulations in the Calandria of an advanced reactor under natural circulation. • Under natural convection, majority of the flow recirculates within the Calandria. • Maximum temperature is located at the top and center of the fuel channel matrix. • During SBO, temperature inside Calandria is stratified. - Abstract: Passive systems are being examined for the future Advanced Nuclear Reactor designs. One of such concepts is the Passive Moderator Cooling System (PMCS), which is designed to remove heat from the moderator in the Calandria vessel passively in case of an extended Station Black Out condition. The heated heavy-water moderator (due to heat transferred from the Main Heat Transport System (MHTS) and thermalization of neutrons and gamma from radioactive decay of fuel) rises upward due to buoyancy, gets cooled down in a heat exchanger and returns back to Calandria, completing a natural circulation loop. The natural circulation should provide sufficient cooling to prevent the increase of moderator temperature and pressure beyond safe limits. In an earlier study, a full-scale 1D transient simulation was performed for the reactor including the MHTS and the PMCS, in the event of a station blackout scenario (Kumar et al., 2013). The results indicate that the systems remain within the safe limits for 7 days. However, the flow inside a geometry like Calandria is quite complex due to its large size and inner complexities of dense fuel channel matrix, which was simplified as a 1D pipe flow in the aforesaid analysis. In the current work, CFD simulations are performed to study the temperature distributions and flow distribution of moderator inside the Calandria vessel using a three-dimensional CFD code, OpenFoam 2.2.0. First, a set of steady state simulation was carried out for a band of inlet mass flow rates, which gives the minimum mass flow rate required for removing the maximum heat load, by virtue of prediction of hot spots inside the Calandria

  16. High Level Requirements for the Nuclear Energy -- Knowledge Base for Advanced Modeling and Simulation (NE-KAMS)

    Energy Technology Data Exchange (ETDEWEB)

    Rich Johnson; Hyung Lee; Kimberlyn C. Mousseau

    2011-09-01

    The US Department of Energy, Office of Nuclear Energy (DOE-NE), has been tasked with the important mission of ensuring that nuclear energy remains a compelling and viable energy source in the U.S. The motivations behind this mission include cost-effectively meeting the expected increases in the power needs of the country, reducing carbon emissions and reducing dependence on foreign energy sources. In the near term, to ensure that nuclear power remains a key element of U.S. energy strategy and portfolio, the DOE-NE will be working with the nuclear industry to support safe and efficient operations of existing nuclear power plants. In the long term, to meet the increasing energy needs of the U.S., the DOE-NE will be investing in research and development (R&D) and working in concert with the nuclear industry to build and deploy new, safer and more efficient nuclear power plants. The safe and efficient operations of existing nuclear power plants and designing, licensing and deploying new reactor designs, however, will require focused R&D programs as well as the extensive use and leveraging of advanced modeling and simulation (M&S). M&S will play a key role in ensuring safe and efficient operations of existing and new nuclear reactors. The DOE-NE has been actively developing and promoting the use of advanced M&S in reactor design and analysis through its R&D programs, e.g., the Nuclear Energy Advanced Modeling and Simulation (NEAMS) and Consortium for Advanced Simulation of Light Water Reactors (CASL) programs. Also, nuclear reactor vendors are already using CFD and CSM, for design, analysis, and licensing. However, these M&S tools cannot be used with confidence for nuclear reactor applications unless accompanied and supported by verification and validation (V&V) and uncertainty quantification (UQ) processes and procedures which provide quantitative measures of uncertainty for specific applications. The Nuclear Energy Knowledge base for Advanced Modeling and Simulation

  17. Comparison of simplified and advanced building simulation tool with measured data

    DEFF Research Database (Denmark)

    Christensen, Jørgen Erik; Schiønning, Peder; Dethlefsen, Espen

    2013-01-01

    In the future building design must progress to a format where CO 2 neutral societies are optimized as a whole and innovative technologies integrated. The purpose of this paper is to demonstrate the problems using a simplified design tool to simulate a complicated building and how this may not give...

  18. Advanced Signal Processing for Integrated LES-RANS Simulations: Anti-aliasing Filters

    Science.gov (United States)

    Schlueter, J. U.

    2003-01-01

    Currently, a wide variety of flow phenomena are addressed with numerical simulations. Many flow solvers are optimized to simulate a limited spectrum of flow effects effectively, such as single parts of a flow system, but are either inadequate or too expensive to be applied to a very complex problem. As an example, the flow through a gas turbine can be considered. In the compressor and the turbine section, the flow solver has to be able to handle the moving blades, model the wall turbulence, and predict the pressure and density distribution properly. This can be done by a flow solver based on the Reynolds-Averaged Navier-Stokes (RANS) approach. On the other hand, the flow in the combustion chamber is governed by large scale turbulence, chemical reactions, and the presence of fuel spray. Experience shows that these phenomena require an unsteady approach. Hence, for the combustor, the use of a Large Eddy Simulation (LES) flow solver is desirable. While many design problems of a single flow passage can be addressed by separate computations, only the simultaneous computation of all parts can guarantee the proper prediction of multi-component phenomena, such as compressor/combustor instability and combustor/turbine hot-streak migration. Therefore, a promising strategy to perform full aero-thermal simulations of gas-turbine engines is the use of a RANS flow solver for the compressor sections, an LES flow solver for the combustor, and again a RANS flow solver for the turbine section.

  19. RECENT ADVANCES OF UPSCALING METHODS FOR THE SIMULATION OF FLOW TRANSPORT THROUGH HETEROGENEOUS POROUS MEDIA

    Institute of Scientific and Technical Information of China (English)

    Zhiming Chen

    2006-01-01

    We review some of our recent efforts in developing upscaling methods for simulating the flow transport through heterogeneous porous media. In particular, the steady flow transport through highly heterogeneous porous media driven by extraction wells and the flow transport through unsaturated porous media will be considered.

  20. ANNUAL REPORT. DEVELOPMENT OF ADVANCED ELECTROCHEMICAL EMISSION SPECTROSCOPY FOR MONITORING CORROSION IN SIMULATED DOE LIQUID WASTE

    Science.gov (United States)

    The current report summarizes work performed on the project over the past calendar year (2001). The work concentrated on four areas: the fracture of AISI 4340 steel simulating weld heat affected zones in DOE liquid waste storage tanks, investigation of the passive state on nickel...