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Sample records for multiphysics simulation capability

  1. Multiscale Modeling of Nano-scale Phenomena: Towards a Multiphysics Simulation Capability for Design and Optimization of Sensor Systems

    Energy Technology Data Exchange (ETDEWEB)

    Becker, R; McElfresh, M; Lee, C; Balhorn, R; White, D

    2003-12-01

    In this white paper, a road map is presented to establish a multiphysics simulation capability for the design and optimization of sensor systems that incorporate nanomaterials and technologies. The Engineering Directorate's solid/fluid mechanics and electromagnetic computer codes will play an important role in both multiscale modeling and integration of required physics issues to achieve a baseline simulation capability. Molecular dynamic simulations performed primarily in the BBRP, CMS and PAT directorates, will provide information for the construction of multiscale models. All of the theoretical developments will require closely coupled experimental work to develop material models and validate simulations. The plan is synergistic and complimentary with the Laboratory's emerging core competency of multiscale modeling. The first application of the multiphysics computer code is the simulation of a ''simple'' biological system (protein recognition utilizing synthesized ligands) that has a broad range of applications including detection of biological threats, presymptomatic detection of illnesses, and drug therapy. While the overall goal is to establish a simulation capability, the near-term work is mainly focused on (1) multiscale modeling, i.e., the development of ''continuum'' representations of nanostructures based on information from molecular dynamics simulations and (2) experiments for model development and validation. A list of LDRDER proposals and ongoing projects that could be coordinated to achieve these near-term objectives and demonstrate the feasibility and utility of a multiphysics simulation capability is given.

  2. Progress on the Multiphysics Capabilities of the Parallel Electromagnetic ACE3P Simulation Suite

    Energy Technology Data Exchange (ETDEWEB)

    Kononenko, Oleksiy [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-03-26

    ACE3P is a 3D parallel simulation suite that is being developed at SLAC National Accelerator Laboratory. Effectively utilizing supercomputer resources, ACE3P has become a key tool for the coupled electromagnetic, thermal and mechanical research and design of particle accelerators. Based on the existing finite-element infrastructure, a massively parallel eigensolver is developed for modal analysis of mechanical structures. It complements a set of the multiphysics tools in ACE3P and, in particular, can be used for the comprehensive study of microphonics in accelerating cavities ensuring the operational reliability of a particle accelerator.

  3. Multiphysics Simulations: Challenges and Opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Keyes, David; McInnes, Lois C.; Woodward, Carol; Gropp, William; Myra, Eric; Pernice, Michael; Bell, John; Brown, Jed; Clo, Alain; Connors, Jeffrey; Constantinescu, Emil; Estep, Don; Evans, Kate; Farhat, Charbel; Hakim, Ammar; Hammond, Glenn E.; Hansen, Glen; Hill, Judith; Isaac, Tobin; Jiao, Xiangmin; Jordan, Kirk; Kaushik, Dinesh; Kaxiras, Efthimios; Koniges, Alice; Lee, Ki Hwan; Lott, Aaron; Lu, Qiming; Magerlein, John; Maxwell, Reed M.; McCourt, Michael; Mehl, Miriam; Pawlowski, Roger; Randles, Amanda; Reynolds, Daniel; Riviere, Beatrice; Rude, Ulrich; Scheibe, Timothy D.; Shadid, John; Sheehan, Brendan; Shephard, Mark; Siegel, Andrew; Smith, Barry; Tang, Xianzhu; Wilson, Cian; Wohlmuth, Barbara

    2013-02-12

    We consider multiphysics applications from algorithmic and architectural perspectives, where ‘‘algorithmic’’ includes both mathematical analysis and computational complexity, and ‘‘architectural’’ includes both software and hardware environments. Many diverse multiphysics applications can be reduced, en route to their computational simulation, to a common algebraic coupling paradigm. Mathematical analysis of multiphysics coupling in this form is not always practical for realistic applications, but model problems representative of applications discussed herein can provide insight. A variety of software frameworks for multiphysics applications have been constructed and refined within disciplinary communities and executed on leading-edge computer systems. We examine several of these, expose some commonalities among them, and attempt to extrapolate best practices to future systems. From our study, we summarize challenges and forecast opportunities.

  4. Multiphysics simulations: Challenges and opportunities

    KAUST Repository

    Keyes, David E.

    2013-02-01

    We consider multiphysics applications from algorithmic and architectural perspectives, where "algorithmic" includes both mathematical analysis and computational complexity, and "architectural" includes both software and hardware environments. Many diverse multiphysics applications can be reduced, en route to their computational simulation, to a common algebraic coupling paradigm. Mathematical analysis of multiphysics coupling in this form is not always practical for realistic applications, but model problems representative of applications discussed herein can provide insight. A variety of software frameworks for multiphysics applications have been constructed and refined within disciplinary communities and executed on leading-edge computer systems. We examine several of these, expose some commonalities among them, and attempt to extrapolate best practices to future systems. From our study, we summarize challenges and forecast opportunities. © The Author(s) 2012.

  5. Multiphysics simulations: challenges and opportunities.

    Energy Technology Data Exchange (ETDEWEB)

    Keyes, D.; McInnes, L. C.; Woodward, C.; Gropp, W.; Myra, E.; Pernice, M. (Mathematics and Computer Science); (KAUST and Columbia Univ.); (Lawrence Livermore National Laboratory); (Univ. of Illinois at Urbana-Champaign); (Univ. of Mich.); (Idaho National Lab.)

    2012-11-29

    This report is an outcome of the workshop Multiphysics Simulations: Challenges and Opportunities, sponsored by the Institute of Computing in Science (ICiS). Additional information about the workshop, including relevant reading and presentations on multiphysics issues in applications, algorithms, and software, is available via https://sites.google.com/site/icismultiphysics2011/. We consider multiphysics applications from algorithmic and architectural perspectives, where 'algorithmic' includes both mathematical analysis and computational complexity and 'architectural' includes both software and hardware environments. Many diverse multiphysics applications can be reduced, en route to their computational simulation, to a common algebraic coupling paradigm. Mathematical analysis of multiphysics coupling in this form is not always practical for realistic applications, but model problems representative of applications discussed herein can provide insight. A variety of software frameworks for multiphysics applications have been constructed and refined within disciplinary communities and executed on leading-edge computer systems. We examine several of these, expose some commonalities among them, and attempt to extrapolate best practices to future systems. From our study, we summarize challenges and forecast opportunities. We also initiate a modest suite of test problems encompassing features present in many applications.

  6. Multiphysical Simulation of Laser Material Processing

    Science.gov (United States)

    Otto, Andreas; Koch, Holger; Vazquez, Rodrigo Gomez

    Within this paper a multiphysical simulation model is presented that is capable for simulating a wide range of laser processes like e.g. laser beam welding, brazing, cutting, drilling or ablation. Some important aspects of the model are explained more in detail and results from test cases are compared with analytical solutions revealing the high accuracy of the model. Finally exemplary results from process simulations on laser beam remote cutting of steel and laser beam scribing of silicon wafers are given.

  7. Multidimensional multiphysics simulation of nuclear fuel behavior

    Science.gov (United States)

    Williamson, R. L.; Hales, J. D.; Novascone, S. R.; Tonks, M. R.; Gaston, D. R.; Permann, C. J.; Andrs, D.; Martineau, R. C.

    2012-04-01

    Nuclear fuel operates in an environment that induces complex multiphysics phenomena, occurring over distances ranging from inter-atomic spacing to meters, and times scales ranging from microseconds to years. This multiphysics behavior is often tightly coupled and many important aspects are inherently multidimensional. Most current fuel modeling codes employ loose multiphysics coupling and are restricted to 2D axisymmetric or 1.5D approximations. This paper describes a new modeling tool able to simulate coupled multiphysics and multiscale fuel behavior, for either 2D axisymmetric or 3D geometries. Specific fuel analysis capabilities currently implemented in this tool are described, followed by a set of demonstration problems which include a 10-pellet light water reactor fuel rodlet, three-dimensional analysis of pellet clad mechanical interaction in the vicinity of a defective fuel pellet, coupled heat transfer and fission product diffusion in a TRISO-coated fuel particle, a demonstration of the ability to couple to lower-length scale models to account for material property variation with microstructural evolution, and a demonstration of the tool's ability to efficiently solve very large and complex problems using massively-parallel computing. A final section describes an early validation exercise, comparing simulation results to a light water reactor fuel rod experiment.

  8. Automating Embedded Analysis Capabilities and Managing Software Complexity in Multiphysics Simulation, Part I: Template-Based Generic Programming

    Directory of Open Access Journals (Sweden)

    Roger P. Pawlowski

    2012-01-01

    Full Text Available An approach for incorporating embedded simulation and analysis capabilities in complex simulation codes through template-based generic programming is presented. This approach relies on templating and operator overloading within the C++ language to transform a given calculation into one that can compute a variety of additional quantities that are necessary for many state-of-the-art simulation and analysis algorithms. An approach for incorporating these ideas into complex simulation codes through general graph-based assembly is also presented. These ideas have been implemented within a set of packages in the Trilinos framework and are demonstrated on a simple problem from chemical engineering.

  9. Multi-physics CFD simulations in engineering

    Science.gov (United States)

    Yamamoto, Makoto

    2013-08-01

    Nowadays Computational Fluid Dynamics (CFD) software is adopted as a design and analysis tool in a great number of engineering fields. We can say that single-physics CFD has been sufficiently matured in the practical point of view. The main target of existing CFD software is single-phase flows such as water and air. However, many multi-physics problems exist in engineering. Most of them consist of flow and other physics, and the interactions between different physics are very important. Obviously, multi-physics phenomena are critical in developing machines and processes. A multi-physics phenomenon seems to be very complex, and it is so difficult to be predicted by adding other physics to flow phenomenon. Therefore, multi-physics CFD techniques are still under research and development. This would be caused from the facts that processing speed of current computers is not fast enough for conducting a multi-physics simulation, and furthermore physical models except for flow physics have not been suitably established. Therefore, in near future, we have to develop various physical models and efficient CFD techniques, in order to success multi-physics simulations in engineering. In the present paper, I will describe the present states of multi-physics CFD simulations, and then show some numerical results such as ice accretion and electro-chemical machining process of a three-dimensional compressor blade which were obtained in my laboratory. Multi-physics CFD simulations would be a key technology in near future.

  10. Multiphysics simulation electromechanical system applications and optimization

    CERN Document Server

    Dede, Ercan M; Nomura, Tsuyoshi

    2014-01-01

    This book highlights a unique combination of numerical tools and strategies for handling the challenges of multiphysics simulation, with a specific focus on electromechanical systems as the target application. Features: introduces the concept of design via simulation, along with the role of multiphysics simulation in today's engineering environment; discusses the importance of structural optimization techniques in the design and development of electromechanical systems; provides an overview of the physics commonly involved with electromechanical systems for applications such as electronics, ma

  11. Automating embedded analysis capabilities and managing software complexity in multiphysics simulation part II: application to partial differential equations

    CERN Document Server

    Pawlowski, Roger P; Salinger, Andrew G; Owen, Steven J; Siefert, Christopher M; Staten, Matthew L

    2012-01-01

    A template-based generic programming approach was presented in a previous paper that separates the development effort of programming a physical model from that of computing additional quantities, such as derivatives, needed for embedded analysis algorithms. In this paper, we describe the implementation details for using the template-based generic programming approach for simulation and analysis of partial differential equations (PDEs). We detail several of the hurdles that we have encountered, and some of the software infrastructure developed to overcome them. We end with a demonstration where we present shape optimization and uncertainty quantification results for a 3D PDE application.

  12. Automating Embedded Analysis Capabilities and Managing Software Complexity in Multiphysics Simulation, Part II: Application to Partial Differential Equations

    Directory of Open Access Journals (Sweden)

    Roger P. Pawlowski

    2012-01-01

    Full Text Available A template-based generic programming approach was presented in Part I of this series of papers [Sci. Program. 20 (2012, 197–219] that separates the development effort of programming a physical model from that of computing additional quantities, such as derivatives, needed for embedded analysis algorithms. In this paper, we describe the implementation details for using the template-based generic programming approach for simulation and analysis of partial differential equations (PDEs. We detail several of the hurdles that we have encountered, and some of the software infrastructure developed to overcome them. We end with a demonstration where we present shape optimization and uncertainty quantification results for a 3D PDE application.

  13. Plasma Simulation in the Multiphysics Object Oriented Simulation Environment MOOSE

    Science.gov (United States)

    Shannon, Steven; Lindsay, Alex; Graves, David; Icenhour, Casey; Peterson, David; White, Scott

    2016-09-01

    MOOSE is an open source multiphysics solver developed by Idaho National Laboratory that is primarily used for the simulation of fission reactor systems; the framework is also well suited for the simulation of plasma systems given the development of appropriate modules not currently developed in the framework such as electromagnetic solvers, Boltzmann solvers, etc. It is structured for user development of application specific modules and is intended for both workstation level and high performance massively parallel environments. We have begun the development of plasma modules in the MOOSE environment and carried out preliminary simulation of the plasma/liquid interface to elucidate coupling mechanisms between these states using a fully coupled multiphysics model; these results agree well with PIC simulation of the same system and show strong response of plasma parameters with respect to electron reflection at the liquid surface. These results will be presented along with an overview of MOOSE and ongoing module development to extend capabilities to a broader set of research challenges in low temperature plasmas, with particular focus on RF and pulsed RF driven systems.

  14. A MULTIDIMENSIONAL AND MULTIPHYSICS APPROACH TO NUCLEAR FUEL BEHAVIOR SIMULATION

    Energy Technology Data Exchange (ETDEWEB)

    R. L. Williamson; J. D. Hales; S. R. Novascone; M. R. Tonks; D. R. Gaston; C. J. Permann; D. Andrs; R. C. Martineau

    2012-04-01

    Important aspects of fuel rod behavior, for example pellet-clad mechanical interaction (PCMI), fuel fracture, oxide formation, non-axisymmetric cooling, and response to fuel manufacturing defects, are inherently multidimensional in addition to being complicated multiphysics problems. Many current modeling tools are strictly 2D axisymmetric or even 1.5D. This paper outlines the capabilities of a new fuel modeling tool able to analyze either 2D axisymmetric or fully 3D models. These capabilities include temperature-dependent thermal conductivity of fuel; swelling and densification; fuel creep; pellet fracture; fission gas release; cladding creep; irradiation growth; and gap mechanics (contact and gap heat transfer). The need for multiphysics, multidimensional modeling is then demonstrated through a discussion of results for a set of example problems. The first, a 10-pellet rodlet, demonstrates the viability of the solution method employed. This example highlights the effect of our smeared cracking model and also shows the multidimensional nature of discrete fuel pellet modeling. The second example relies on our the multidimensional, multiphysics approach to analyze a missing pellet surface problem. As a final example, we show a lower-length-scale simulation coupled to a continuum-scale simulation.

  15. Simulation of Multiphysics Multiscale Systems, 6th International Workshop

    NARCIS (Netherlands)

    Krzhizhanovskaya, V.V.

    2009-01-01

    Modeling and Simulation of Multiphysics Multiscale Systems (SMMS) poses a grand challenge to computational science. To adequately simulate numerous intertwined processes characterized by different spatial and temporal scales spanning many orders of magnitude, sophisticated models and advanced comput

  16. Simulation of Multiphysics Multiscale Systems, 7th International Workshop

    NARCIS (Netherlands)

    Krzhizhanovskaya, V.

    2010-01-01

    Modeling and Simulation of Multiphysics Multiscale Systems (SMMS) poses a grand challenge to computational science. To adequately simulate numerous intertwined processes characterized by different spatial and temporal scales spanning many orders of magnitude, sophisticated models and advanced comput

  17. Simulation of Multiphysics Multiscale Systems, 5th International Workshop

    NARCIS (Netherlands)

    Krzhizhanovskaya, V.V.; Hoekstra, A.G.

    2008-01-01

    Modeling and Simulation of Multiphysics Multiscale Systems (SMMS) poses a grand challenge to computational science. To adequately simulate numerous intertwined processes characterized by different spatial and temporal scales spanning many orders of magnitude, sophisticated models and advanced comput

  18. Advanced Mesh-Enabled Monte carlo capability for Multi-Physics Reactor Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Paul; Evans, Thomas; Tautges, Tim

    2012-12-24

    This project will accumulate high-precision fluxes throughout reactor geometry on a non- orthogonal grid of cells to support multi-physics coupling, in order to more accurately calculate parameters such as reactivity coefficients and to generate multi-group cross sections. This work will be based upon recent developments to incorporate advanced geometry and mesh capability in a modular Monte Carlo toolkit with computational science technology that is in use in related reactor simulation software development. Coupling this capability with production-scale Monte Carlo radiation transport codes can provide advanced and extensible test-beds for these developments. Continuous energy Monte Carlo methods are generally considered to be the most accurate computational tool for simulating radiation transport in complex geometries, particularly neutron transport in reactors. Nevertheless, there are several limitations for their use in reactor analysis. Most significantly, there is a trade-off between the fidelity of results in phase space, statistical accuracy, and the amount of computer time required for simulation. Consequently, to achieve an acceptable level of statistical convergence in high-fidelity results required for modern coupled multi-physics analysis, the required computer time makes Monte Carlo methods prohibitive for design iterations and detailed whole-core analysis. More subtly, the statistical uncertainty is typically not uniform throughout the domain, and the simulation quality is limited by the regions with the largest statistical uncertainty. In addition, the formulation of neutron scattering laws in continuous energy Monte Carlo methods makes it difficult to calculate adjoint neutron fluxes required to properly determine important reactivity parameters. Finally, most Monte Carlo codes available for reactor analysis have relied on orthogonal hexahedral grids for tallies that do not conform to the geometric boundaries and are thus generally not well

  19. Multiphysics Modelling and Simulation for Systems Design Conference

    CERN Document Server

    Abbes, Mohamed; Choley, Jean-Yves; Boukharouba, Taoufik; Elnady, Tamer; Kanaev, Andrei; Amar, Mounir; Chaari, Fakher

    2015-01-01

    This book reports on the state of the art in the field of multiphysics systems. It consists of accurately reviewed contributions to the MMSSD’2014 conference, which was held from December 17 to 19, 2004 in Hammamet, Tunisia. The different chapters, covering new theories, methods and a number of case studies, provide readers with an up-to-date picture of multiphysics modeling and simulation. They highlight the role played by high-performance computing and newly available software in promoting the study of multiphysics coupling effects, and show how these technologies can be practically implemented to bring about significant improvements in the field of design, control and monitoring of machines.  In addition to providing a detailed description of the methods and their applications, the book also identifies new research issues, challenges and opportunities, thus providing researchers and practitioners with both technical information to support their daily work and a new source of inspiration for their future...

  20. Final Report: Quantifying Prediction Fidelity in Multiscale Multiphysics Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Long, Kevin [Texas Tech University

    2014-09-30

    We have developed algorithms and software in support of uncertainty quantification in nonlinear multiphysics simulations. This work includes high-level, high-performance software for large-scale, matrix-free linear algebra and a new algorithm for fast computation of transcendental functions of stochastic variables.

  1. Multi-Physics Simulation of Wood Drying in COMSOL Multiphysics 3.4.

    Directory of Open Access Journals (Sweden)

    Sandoval-Torres Sadoth

    2013-06-01

    Full Text Available In this work, the numerical simulation of drying of Pinus pesudostrobus wood is presented by using a phenomenological model. The model is developed by considering the heat and mass balance in the representative elementary volume (REV, which involves the solid, liquid and gas phases. We obtained a system of partial differential equations which was solved by numerical factorization by using COMSOL multiphysics 3.4. Three primary variables were solved: the moisture content, the temperature, and the dry-air mass. The numerical results were compared against experimental data and the semi-empirical model. Our results are satisfactory; we describe the drying kinetics, the moisture distribution within the wood, the dry-air mass evolution and the temperature profiles.

  2. Quench Simulation of Superconducting Magnets with Commercial Multiphysics Software

    CERN Document Server

    AUTHOR|(SzGeCERN)751171; Auchmann, Bernhard; Jarkko, Niiranen; Maciejewski, Michal

    The simulation of quenches in superconducting magnets is a multiphysics problem of highest complexity. Operated at 1.9 K above absolute zero, the material properties of superconductors and superfluid helium vary by several orders of magnitude over a range of only 10 K. The heat transfer from metal to helium goes through different transfer and boiling regimes as a function of temperature, heat flux, and transferred energy. Electrical, magnetic, thermal, and fluid dynamic effects are intimately coupled, yet live on vastly different time and spatial scales. While the physical models may be the same in all cases, it is an open debate whether the user should opt for commercial multiphysics software like ANSYS or COMSOL, write customized models based on general purpose network solvers like SPICE, or implement the physics models and numerical solvers entirely in custom software like the QP3, THEA, and ROXIE codes currently in use at the European Organisation for Nuclear Research (CERN). Each approach has its strengt...

  3. High-Fidelity Space-Time Adaptive Multiphysics Simulations in Nuclear Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Solin, Pavel [Univ. of Reno, NV (United States); Ragusa, Jean [Texas A & M Univ., College Station, TX (United States)

    2014-03-09

    We delivered a series of fundamentally new computational technologies that have the potential to significantly advance the state-of-the-art of computer simulations of transient multiphysics nuclear reactor processes. These methods were implemented in the form of a C++ library, and applied to a number of multiphysics coupled problems relevant to nuclear reactor simulations.

  4. Multiphysics simulation of corona discharge induced ionic wind

    CERN Document Server

    Cagnoni, Davide; Christen, Thomas; de Falco, Carlo; Parolini, Nicola; Stevanović, Ivica

    2013-01-01

    Ionic wind devices or electrostatic fluid accelerators are becoming of increasing interest as tools for thermal management, in particular for semiconductor devices. In this work, we present a numerical model for predicting the performance of such devices, whose main benefit is the ability to accurately predict the amount of charge injected at the corona electrode. Our multiphysics numerical model consists of a highly nonlinear strongly coupled set of PDEs including the Navier-Stokes equations for fluid flow, Poisson's equation for electrostatic potential, charge continuity and heat transfer equations. To solve this system we employ a staggered solution algorithm that generalizes Gummel's algorithm for charge transport in semiconductors. Predictions of our simulations are validated by comparison with experimental measurements and are shown to closely match. Finally, our simulation tool is used to estimate the effectiveness of the design of an electrohydrodynamic cooling apparatus for power electronics applicat...

  5. Multiphysics simulation of corona discharge induced ionic wind

    Energy Technology Data Exchange (ETDEWEB)

    Cagnoni, Davide [ABB Switzerland Ltd., Corporate Research, CH-5405 Baden-Dättwil (Switzerland); MOX - Dipartimento di Matematica “F. Brioschi,” Politecnico di Milano, 20133 Milano (Italy); Agostini, Francesco; Christen, Thomas [ABB Switzerland Ltd., Corporate Research, CH-5405 Baden-Dättwil (Switzerland); Parolini, Nicola [MOX - Dipartimento di Matematica “F. Brioschi,” Politecnico di Milano, 20133 Milano (Italy); Stevanović, Ivica [ABB Switzerland Ltd., Corporate Research, CH-5405 Baden-Dättwil (Switzerland); Laboratory of Electromagnetics and Acoustics, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne (Switzerland); Falco, Carlo de [MOX - Dipartimento di Matematica “F. Brioschi,” Politecnico di Milano, 20133 Milano (Italy); CEN - Centro Europeo di Nanomedicina, 20133 Milano (Italy)

    2013-12-21

    Ionic wind devices or electrostatic fluid accelerators are becoming of increasing interest as tools for thermal management, in particular for semiconductor devices. In this work, we present a numerical model for predicting the performance of such devices; its main benefit is the ability to accurately predict the amount of charge injected from the corona electrode. Our multiphysics numerical model consists of a highly nonlinear, strongly coupled set of partial differential equations including the Navier-Stokes equations for fluid flow, Poisson's equation for electrostatic potential, charge continuity, and heat transfer equations. To solve this system we employ a staggered solution algorithm that generalizes Gummel's algorithm for charge transport in semiconductors. Predictions of our simulations are verified and validated by comparison with experimental measurements of integral physical quantities, which are shown to closely match.

  6. Petascale computation of multi-physics seismic simulations

    Science.gov (United States)

    Gabriel, Alice-Agnes; Madden, Elizabeth H.; Ulrich, Thomas; Wollherr, Stephanie; Duru, Kenneth C.

    2017-04-01

    Capturing the observed complexity of earthquake sources in concurrence with seismic wave propagation simulations is an inherently multi-scale, multi-physics problem. In this presentation, we present simulations of earthquake scenarios resolving high-detail dynamic rupture evolution and high frequency ground motion. The simulations combine a multitude of representations of model complexity; such as non-linear fault friction, thermal and fluid effects, heterogeneous fault stress and fault strength initial conditions, fault curvature and roughness, on- and off-fault non-elastic failure to capture dynamic rupture behavior at the source; and seismic wave attenuation, 3D subsurface structure and bathymetry impacting seismic wave propagation. Performing such scenarios at the necessary spatio-temporal resolution requires highly optimized and massively parallel simulation tools which can efficiently exploit HPC facilities. Our up to multi-PetaFLOP simulations are performed with SeisSol (www.seissol.org), an open-source software package based on an ADER-Discontinuous Galerkin (DG) scheme solving the seismic wave equations in velocity-stress formulation in elastic, viscoelastic, and viscoplastic media with high-order accuracy in time and space. Our flux-based implementation of frictional failure remains free of spurious oscillations. Tetrahedral unstructured meshes allow for complicated model geometry. SeisSol has been optimized on all software levels, including: assembler-level DG kernels which obtain 50% peak performance on some of the largest supercomputers worldwide; an overlapping MPI-OpenMP parallelization shadowing the multiphysics computations; usage of local time stepping; parallel input and output schemes and direct interfaces to community standard data formats. All these factors enable aim to minimise the time-to-solution. The results presented highlight the fact that modern numerical methods and hardware-aware optimization for modern supercomputers are essential

  7. 3D multiphysics modeling of superconducting cavities with a massively parallel simulation suite

    Directory of Open Access Journals (Sweden)

    Oleksiy Kononenko

    2017-10-01

    Full Text Available Radiofrequency cavities based on superconducting technology are widely used in particle accelerators for various applications. The cavities usually have high quality factors and hence narrow bandwidths, so the field stability is sensitive to detuning from the Lorentz force and external loads, including vibrations and helium pressure variations. If not properly controlled, the detuning can result in a serious performance degradation of a superconducting accelerator, so an understanding of the underlying detuning mechanisms can be very helpful. Recent advances in the simulation suite ace3p have enabled realistic multiphysics characterization of such complex accelerator systems on supercomputers. In this paper, we present the new capabilities in ace3p for large-scale 3D multiphysics modeling of superconducting cavities, in particular, a parallel eigensolver for determining mechanical resonances, a parallel harmonic response solver to calculate the response of a cavity to external vibrations, and a numerical procedure to decompose mechanical loads, such as from the Lorentz force or piezoactuators, into the corresponding mechanical modes. These capabilities have been used to do an extensive rf-mechanical analysis of dressed TESLA-type superconducting cavities. The simulation results and their implications for the operational stability of the Linac Coherent Light Source-II are discussed.

  8. A Coupled Multiphysics Approach for Simulating Induced Seismicity, Ground Acceleration and Structural Damage

    Science.gov (United States)

    Podgorney, Robert; Coleman, Justin; Wilkins, Amdrew; Huang, Hai; Veeraraghavan, Swetha; Xia, Yidong; Permann, Cody

    2017-04-01

    Numerical modeling has played an important role in understanding the behavior of coupled subsurface thermal-hydro-mechanical (THM) processes associated with a number of energy and environmental applications since as early as the 1970s. While the ability to rigorously describe all key tightly coupled controlling physics still remains a challenge, there have been significant advances in recent decades. These advances are related primarily to the exponential growth of computational power, the development of more accurate equations of state, improvements in the ability to represent heterogeneity and reservoir geometry, and more robust nonlinear solution schemes. The work described in this paper documents the development and linkage of several fully-coupled and fully-implicit modeling tools. These tools simulate: (1) the dynamics of fluid flow, heat transport, and quasi-static rock mechanics; (2) seismic wave propagation from the sources of energy release through heterogeneous material; and (3) the soil-structural damage resulting from ground acceleration. These tools are developed in Idaho National Laboratory's parallel Multiphysics Object Oriented Simulation Environment, and are integrated together using a global implicit approach. The governing equations are presented, the numerical approach for simultaneously solving and coupling the three coupling physics tools is discussed, and the data input and output methodology is outlined. An example is presented to demonstrate the capabilities of the coupled multiphysics approach. The example involves simulating a system conceptually similar to the geothermal development in Basel Switzerland, and the resultant induced seismicity, ground motion and structural damage is predicted.

  9. Multi-physical field coupling simulation of TCVI process for preparing carbon/carbon composites

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    To prepare Carbon/Carbon (C/C) composites with advanced performance, the thermal gradient chemical vapor infiltration (TCVI) process has been optimized by simulation. A 2D axisymmetric unstable model was built, which included convection, conduction, diffusion, densification reactions in the pores and the evolution of the porous medium. The multi-physical field coupling model was solved by finite element method (FEM) and iterative calculation. The time evolution of the fluid, temperature and preform density field were obtained by the calculation. It is indicated that convection strongly affects the temperature field. For the preform of carbon/carbon composites infiltrated for 100 h by TCVI, the radial average densities from simulation agrees well with those from experiment. The model is validated to be reliable and the simulation has capability of forecasting the process.

  10. Multi-physical field coupling simulation of TCVI process for preparing carbon/carbon composites

    Institute of Scientific and Technical Information of China (English)

    JIAO YanQiong; LI HeJun; LI KeZhi

    2009-01-01

    To prepare Carbon/Carbon (C/C) composites with advanced performance, the thermal gradient chemi-cal vapor infiltration (TCVI) process has been optimized by simulation.A 2D axisymmetric unstable model was built, which included convection, conduction, diffusion, densification reactions in the pores and the evolution of the porous medium.The multi-physical field coupling model was solved by finite element method (FEM) and iterative calculation.The time evolution of the fluid, temperature and pre-form density field were obtained by the calculation.It is indicated that convection strongly affects the temperature field.For the preform of carbon/carbon composites infiltrated for 100 h by TCVI, the radial average densities from simulation agrees well with those from experiment.The model is validated to be reliable and the simulation has capability of forecasting the process.

  11. Managing structure complexity in a multi-physic simulation software

    OpenAIRE

    Huynh, Quoc Hung; Maréchal, Yves; Coulomb, Jean-Louis

    2006-01-01

    International audience; This paper presents an efficient method for managing the complexity of software structure by implementing the business rules over the data model using a combination of logical programming and object-oriented programming, concretely applied in a multiphysics application.

  12. An introduction to LIME 1.0 and its use in coupling codes for multiphysics simulations.

    Energy Technology Data Exchange (ETDEWEB)

    Belcourt, Noel; Pawlowski, Roger Patrick; Schmidt, Rodney Cannon; Hooper, Russell Warren

    2011-11-01

    LIME is a small software package for creating multiphysics simulation codes. The name was formed as an acronym denoting 'Lightweight Integrating Multiphysics Environment for coupling codes.' LIME is intended to be especially useful when separate computer codes (which may be written in any standard computer language) already exist to solve different parts of a multiphysics problem. LIME provides the key high-level software (written in C++), a well defined approach (with example templates), and interface requirements to enable the assembly of multiple physics codes into a single coupled-multiphysics simulation code. In this report we introduce important software design characteristics of LIME, describe key components of a typical multiphysics application that might be created using LIME, and provide basic examples of its use - including the customized software that must be written by a user. We also describe the types of modifications that may be needed to individual physics codes in order for them to be incorporated into a LIME-based multiphysics application.

  13. Multi-physics simulation of metal printing at micro/nanoscale using meniscus-confined electrodeposition: Effect of environmental humidity

    Science.gov (United States)

    Morsali, Seyedreza; Daryadel, Soheil; Zhou, Zhong; Behroozfar, Ali; Qian, Dong; Minary-Jolandan, Majid

    2017-01-01

    Capability to print metals at micro/nanoscale in arbitrary 3D patterns at local points of interest will have applications in nano-electronics and sensors. Meniscus-confined electrodeposition (MCED) is a manufacturing process that enables depositing metals from an electrolyte containing nozzle (pipette) in arbitrary 3D patterns. In this process, a meniscus (liquid bridge or capillary) between the pipette tip and the substrate governs the localized electrodeposition process. Fabrication of metallic microstructures using this process is a multi-physics process in which electrodeposition, fluid dynamics, and mass and heat transfer physics are simultaneously involved. We utilized multi-physics finite element simulation, guided by experimental data, to understand the effect of water evaporation from the liquid meniscus at the tip of the nozzle for deposition of free-standing copper microwires in MCED process.

  14. Multi-Physics Coupling Approaches for Aerospace Numerical Simulations.

    OpenAIRE

    Errera, M.; Dugeai, A.; Girodroux-Lavigne, P.; Garaud, J.D.; Poinot, M.; Cerqueira, S.; Chaineray, G.

    2011-01-01

    International audience; The purpose of this paper is to present coupling strategies for aerospace numerical calculations. In the first part, the basic approach used relies on the partitioned coupling of a finite-volume Navier-Stokes solver and a finite-element solid code. These two separate and independent simulation tools carry out exchanges via a coupling library. Two different applications illustrate the capabilities of this coupling method. The main advantage of this approach is to benefi...

  15. The Integrated Plasma Simulator: A Flexible Python Framework for Coupled Multiphysics Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Foley, Samantha S [ORNL; Elwasif, Wael R [ORNL; Bernholdt, David E [ORNL

    2011-11-01

    High-fidelity coupled multiphysics simulations are an increasingly important aspect of computational science. In many domains, however, there has been very limited experience with simulations of this sort, therefore research in coupled multiphysics often requires computational frameworks with significant flexibility to respond to the changing directions of the physics and mathematics. This paper presents the Integrated Plasma Simulator (IPS), a framework designed for loosely coupled simulations of fusion plasmas. The IPS provides users with a simple component architecture into which a wide range of existing plasma physics codes can be inserted as components. Simulations can take advantage of multiple levels of parallelism supported in the IPS, and can be controlled by a high-level ``driver'' component, or by other coordination mechanisms, such as an asynchronous event service. We describe the requirements and design of the framework, and how they were implemented in the Python language. We also illustrate the flexibility of the framework by providing examples of different types of simulations that utilize various features of the IPS.

  16. Sound Generation by a Turbulent Flow in Musical Instruments - Multiphysics Simulation Approach -

    CERN Document Server

    Kobayashi, Taizo; Takahashi, Kin'ya; Mibu, Ryota; Aoyagi, Mutsumi

    2007-01-01

    Total computational costs of scientific simulations are analyzed between direct numerical simulations (DNS) and multiphysics simulations (MPS) for sound generation in musical instruments. In order to produce acoustic sound by a turbulent flow in a simple recorder-like instrument, compressible fluid dynamic calculations with a low Mach number are required around the edges and the resonator of the instrument in DNS, while incompressible fluid dynamic calculations coupled with dynamics of sound propagation based on the Lighthill's acoustic analogy are used in MPS. These strategies are evaluated not only from the viewpoint of computational performances but also from the theoretical points of view as tools for scientific simulations of complicated systems.

  17. Full Core Multiphysics Simulation with Offline Mesh Deformation

    Energy Technology Data Exchange (ETDEWEB)

    Merzari, E. [Argonne National Lab. (ANL), Argonne, IL (United States); Shemon, E. R. [Argonne National Lab. (ANL), Argonne, IL (United States); Yu, Y. [Argonne National Lab. (ANL), Argonne, IL (United States); Thomas, J. W. [Argonne National Lab. (ANL), Argonne, IL (United States); Obabko, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Jain, Rajeev [Argonne National Lab. (ANL), Argonne, IL (United States); Mahadevan, Vijay [Argonne National Lab. (ANL), Argonne, IL (United States); Solberg, Jerome [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ferencz, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Whitesides, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-12-21

    In this report, building on previous reports issued in FY13 we describe our continued efforts to integrate thermal/hydraulics, neutronics, and structural mechanics modeling codes to perform coupled analysis of a representative fast sodium-cooled reactor core. The focus of the present report is a full core simulation with off-line mesh deformation.

  18. Multi-physics Simulation of Thermoelectric Generators through Numerically Modeling

    DEFF Research Database (Denmark)

    Chen, Min; Rosendahl, Lasse; Bach, Inger Palsgaard

    2007-01-01

    The governing equations taken from the assumption of local equilibrium and the heat transfer rate form of Onsager flux have been compared with those based on classical heat transfer formulation by a simplified one dimensional (1-D) thermoelectric generator (TEG) model. In this paper, the simulation...

  19. Ventilation Structure Improvement of Induction Motor Using Multiphysics Simulations

    Directory of Open Access Journals (Sweden)

    Tao Huang

    2012-09-01

    Full Text Available Temperature rise analysis has significant impact in the design of air-cooled asynchronous induction motor. However, the affection cannot be accurately evaluated by using traditional empirical curves method due to the complexity of the inductor architecture. Considering Joules losses in stator windings and the induced eddy current in squirrel cages, and heat dissipation by air convection and solid conduction, in this paper a 3-D coupled-field finite-element method (FEM is investigated to demonstrate the temperature distribution. The Joules losses calculated by 3-D eddy- current field analysis are used as the input for the thermal field analysis, which is deeply dependent on accurate air fluid field analysis. A novel multi-component fluid model is employed to deal with the influence of rotor rotation upon the air convection. The simulation results show the fatal influence of the ventilation structure and the effectiveness of the proposed cooling improvement way.

  20. Multiphysics Simulation in the Development of Thermoelectric Energy Harvesting Systems

    Science.gov (United States)

    Nesarajah, Marco; Frey, Georg

    2016-03-01

    This contribution presents a model-based development process for thermoelectric energy harvesting systems. Such systems convert thermal energy into electrical energy and produce enough energy to supply low-power devices. Realizations require three main challenges to be solved: to guarantee optimal thermal connection of the thermoelectric generators, to find a good design for the energy harvesting system, and to find an optimal electrical connection. Therefore, a development process is presented here. The process is divided into different steps and supports the developer in finding an optimal thermoelectric energy harvesting system for a given heat source and given objectives (technical and economical). During the process, several steps are supported by simulation models. Based on developed model libraries in Modelica®/Dymola®, thermal, thermoelectrical, electrical, and control components can be modeled, integrated into different variants, and verified step by step before the system is physically built and finally validated. The process is illustrated by an example through all the steps.

  1. Ventilation Structure Improvement of Induction Motor Using Multiphysics Simulations

    Directory of Open Access Journals (Sweden)

    Xiaowen Wu

    2012-07-01

    Full Text Available Temperature rise analysis has significant impact in the design of air-cooled asynchronous induction motor. However, the affection cannot be accurately evaluated by using traditional empirical curves method due to the complexity of the inductor architecture. Considering Joule’s losses in stator windings and the induced eddy current in squirrel cages, and heat dissipation by air convection and solid conduction, in this paper a 3-D coupled-field finite-element method (FEM is investigated to demonstrate the temperature distribution. The Joule’s losses calculated by 3-D eddy- current field analysis are used as the input for the thermal field analysis, which is deeply dependent on accurate air fluid field analysis. A novel multi-component fluid model is employed to deal with the influence of rotor rotation upon the air convection. The simulation results show the fatal influence of the ventilation structure and the effectiveness of the proposed cooling improvement way.  

  2. Developing highly scalable fluid solvers for enabling multiphysics simulation.

    Energy Technology Data Exchange (ETDEWEB)

    Clausen, Jonathan R

    2013-03-01

    We performed an investigation into explicit algorithms for the simulation of incompressible flows using methods with a finite, but small amount of compressibility added. Such methods include the artificial compressibility method and the lattice-Boltzmann method. The impetus for investigating such techniques stems from the increasing use of parallel computation at all levels (processors, clusters, and graphics processing units). Explicit algorithms have the potential to leverage these resources. In our investigation, a new form of artificial compressibility was derived. This method, referred to as the Entropically Damped Artificial Compressibility (EDAC) method, demonstrated superior results to traditional artificial compressibility methods by damping the numerical acoustic waves associated with these methods. Performance nearing that of the lattice- Boltzmann technique was observed, without the requirement of recasting the problem in terms of particle distribution functions; continuum variables may be used. Several example problems were investigated using a finite-di erence and finite-element discretizations of the EDAC equations. Example problems included lid-driven cavity flow, a convecting Taylor-Green vortex, a doubly periodic shear layer, freely decaying turbulence, and flow over a square cylinder. Additionally, a scalability study was performed using in excess of one million processing cores. Explicit methods were found to have desirable scaling properties; however, some robustness and general applicability issues remained.

  3. Multi-Physics Demonstration Problem with the SHARP Reactor Simulation Toolkit

    Energy Technology Data Exchange (ETDEWEB)

    Merzari, E. [Argonne National Lab. (ANL), Argonne, IL (United States); Shemon, E. R. [Argonne National Lab. (ANL), Argonne, IL (United States); Yu, Y. Q. [Argonne National Lab. (ANL), Argonne, IL (United States); Thomas, J. W. [Argonne National Lab. (ANL), Argonne, IL (United States); Obabko, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Jain, Rajeev [Argonne National Lab. (ANL), Argonne, IL (United States); Mahadevan, Vijay [Argonne National Lab. (ANL), Argonne, IL (United States); Tautges, Timothy [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Solberg, Jerome [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ferencz, Robert Mark [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Whitesides, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-12-21

    This report describes to employ SHARP to perform a first-of-a-kind analysis of the core radial expansion phenomenon in an SFR. This effort required significant advances in the framework Multi-Physics Demonstration Problem with the SHARP Reactor Simulation Toolkit used to drive the coupled simulations, manipulate the mesh in response to the deformation of the geometry, and generate the necessary modified mesh files. Furthermore, the model geometry is fairly complex, and consistent mesh generation for the three physics modules required significant effort. Fully-integrated simulations of a 7-assembly mini-core test problem have been performed, and the results are presented here. Physics models of a full-core model of the Advanced Burner Test Reactor have also been developed for each of the three physics modules. Standalone results of each of the three physics modules for the ABTR are presented here, which provides a demonstration of the feasibility of the fully-integrated simulation.

  4. Development of Multi-physics (Multiphase CFD + MCNP) simulation for generic solution vessel power calculation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Jun [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Buechler, Cynthia Eileen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-07-17

    The current study aims to predict the steady state power of a generic solution vessel and to develop a corresponding heat transfer coefficient correlation for a Moly99 production facility by conducting a fully coupled multi-physics simulation. A prediction of steady state power for the current application is inherently interconnected between thermal hydraulic characteristics (i.e. Multiphase computational fluid dynamics solved by ANSYS-Fluent 17.2) and the corresponding neutronic behavior (i.e. particle transport solved by MCNP6.2) in the solution vessel. Thus, the development of a coupling methodology is vital to understand the system behavior at a variety of system design and postulated operating scenarios. In this study, we report on the k-effective (keff) calculation for the baseline solution vessel configuration with a selected solution concentration using MCNP K-code modeling. The associated correlation of thermal properties (e.g. density, viscosity, thermal conductivity, specific heat) at the selected solution concentration are developed based on existing experimental measurements in the open literature. The numerical coupling methodology between multiphase CFD and MCNP is successfully demonstrated, and the detailed coupling procedure is documented. In addition, improved coupling methods capturing realistic physics in the solution vessel thermal-neutronic dynamics are proposed and tested further (i.e. dynamic height adjustment, mull-cell approach). As a key outcome of the current study, a multi-physics coupling methodology between MCFD and MCNP is demonstrated and tested for four different operating conditions. Those different operating conditions are determined based on the neutron source strength at a fixed geometry condition. The steady state powers for the generic solution vessel at various operating conditions are reported, and a generalized correlation of the heat transfer coefficient for the current application is discussed. The assessment of multi-physics

  5. Multiphysics simulation of fast transients with the FINIX fuel behaviour module

    Directory of Open Access Journals (Sweden)

    Ikonen Timo

    2016-01-01

    Full Text Available FINIX is a recently developed fuel behaviour module that is designed to provide “simple but sufficient” descriptions of the most essential fuel behaviour phenomena in multiphysics simulations. In such simulations, it is possible to obtain significant improvement in the feedback to neutronics or thermal hydraulics modelling even with a relatively simple fuel performance model. In this work, FINIX is used as an internal fuel behaviour module both in reactor physics and in reactor dynamics codes to simulate coupled behaviour in fast transient scenarios. With the Monte Carlo reactor physics code Serpent we model a prompt transient in a VVER-1000 pin cell, and with the reactor dynamics code HEXTRAN, a control rod ejection accident in a VVER-440 reactor.

  6. Electro-Thermal-Mechanical Simulation Capability Final Report

    Energy Technology Data Exchange (ETDEWEB)

    White, D

    2008-02-06

    This is the Final Report for LDRD 04-ERD-086, 'Electro-Thermal-Mechanical Simulation Capability'. The accomplishments are well documented in five peer-reviewed publications and six conference presentations and hence will not be detailed here. The purpose of this LDRD was to research and develop numerical algorithms for three-dimensional (3D) Electro-Thermal-Mechanical simulations. LLNL has long been a world leader in the area of computational mechanics, and recently several mechanics codes have become 'multiphysics' codes with the addition of fluid dynamics, heat transfer, and chemistry. However, these multiphysics codes do not incorporate the electromagnetics that is required for a coupled Electro-Thermal-Mechanical (ETM) simulation. There are numerous applications for an ETM simulation capability, such as explosively-driven magnetic flux compressors, electromagnetic launchers, inductive heating and mixing of metals, and MEMS. A robust ETM simulation capability will enable LLNL physicists and engineers to better support current DOE programs, and will prepare LLNL for some very exciting long-term DoD opportunities. We define a coupled Electro-Thermal-Mechanical (ETM) simulation as a simulation that solves, in a self-consistent manner, the equations of electromagnetics (primarily statics and diffusion), heat transfer (primarily conduction), and non-linear mechanics (elastic-plastic deformation, and contact with friction). There is no existing parallel 3D code for simulating ETM systems at LLNL or elsewhere. While there are numerous magnetohydrodynamic codes, these codes are designed for astrophysics, magnetic fusion energy, laser-plasma interaction, etc. and do not attempt to accurately model electromagnetically driven solid mechanics. This project responds to the Engineering R&D Focus Areas of Simulation and Energy Manipulation, and addresses the specific problem of Electro-Thermal-Mechanical simulation for design and analysis of energy

  7. Consistent multiphysics simulation of a central tower CSP plant as applied to ISTORE

    Science.gov (United States)

    Votyakov, Evgeny V.; Papanicolas, Costas N.

    2017-06-01

    We present a unified consistent multiphysics approach to model a central tower CSP plant. The framework for the model includes Monte Carlo ray tracing (RT) and computational fluid dynamics (CFD) components utilizing the OpenFOAM C++ software library. The RT part works effectively with complex surfaces of engineering design given in CAD formats. The CFD simulation, which is based on 3D Navier-Stokes equations, takes into account all possible heat transfer mechanisms: radiation, conduction, and convection. Utilizing this package, the solar field of the experimental Platform for Research, Observation, and TEchnological Applications in Solar Energy (PROTEAS) and the Integrated STOrage and Receiver (ISTORE), developed at the Cyprus Institute, are being examined.

  8. Numerical simulation and experimental validation of biofilm in a multi-physics framework using an SPH based method

    Science.gov (United States)

    Soleimani, Meisam; Wriggers, Peter; Rath, Henryke; Stiesch, Meike

    2016-10-01

    In this paper, a 3D computational model has been developed to investigate biofilms in a multi-physics framework using smoothed particle hydrodynamics (SPH) based on a continuum approach. Biofilm formation is a complex process in the sense that several physical phenomena are coupled and consequently different time-scales are involved. On one hand, biofilm growth is driven by biological reaction and nutrient diffusion and on the other hand, it is influenced by fluid flow causing biofilm deformation and interface erosion in the context of fluid and deformable solid interaction. The geometrical and numerical complexity arising from these phenomena poses serious complications and challenges in grid-based techniques such as finite element. Here the solution is based on SPH as one of the powerful meshless methods. SPH based computational modeling is quite new in the biological community and the method is uniquely robust in capturing the interface-related processes of biofilm formation such as erosion. The obtained results show a good agreement with experimental and published data which demonstrates that the model is capable of simulating and predicting overall spatial and temporal evolution of biofilm.

  9. Moose: An Open-Source Framework to Enable Rapid Development of Collaborative, Multi-Scale, Multi-Physics Simulation Tools

    Science.gov (United States)

    Slaughter, A. E.; Permann, C.; Peterson, J. W.; Gaston, D.; Andrs, D.; Miller, J.

    2014-12-01

    The Idaho National Laboratory (INL)-developed Multiphysics Object Oriented Simulation Environment (MOOSE; www.mooseframework.org), is an open-source, parallel computational framework for enabling the solution of complex, fully implicit multiphysics systems. MOOSE provides a set of computational tools that scientists and engineers can use to create sophisticated multiphysics simulations. Applications built using MOOSE have computed solutions for chemical reaction and transport equations, computational fluid dynamics, solid mechanics, heat conduction, mesoscale materials modeling, geomechanics, and others. To facilitate the coupling of diverse and highly-coupled physical systems, MOOSE employs the Jacobian-free Newton-Krylov (JFNK) method when solving the coupled nonlinear systems of equations arising in multiphysics applications. The MOOSE framework is written in C++, and leverages other high-quality, open-source scientific software packages such as LibMesh, Hypre, and PETSc. MOOSE uses a "hybrid parallel" model which combines both shared memory (thread-based) and distributed memory (MPI-based) parallelism to ensure efficient resource utilization on a wide range of computational hardware. MOOSE-based applications are inherently modular, which allows for simulation expansion (via coupling of additional physics modules) and the creation of multi-scale simulations. Any application developed with MOOSE supports running (in parallel) any other MOOSE-based application. Each application can be developed independently, yet easily communicate with other applications (e.g., conductivity in a slope-scale model could be a constant input, or a complete phase-field micro-structure simulation) without additional code being written. This method of development has proven effective at INL and expedites the development of sophisticated, sustainable, and collaborative simulation tools.

  10. Tailoring microfluidic systems for organ-like cell culture applications using multiphysics simulations

    Science.gov (United States)

    Hagmeyer, Britta; Schütte, Julia; Böttger, Jan; Gebhardt, Rolf; Stelzle, Martin

    2013-03-01

    Replacing animal testing with in vitro cocultures of human cells is a long-term goal in pre-clinical drug tests used to gain reliable insight into drug-induced cell toxicity. However, current state-of-the-art 2D or 3D cell cultures aiming at mimicking human organs in vitro still lack organ-like morphology and perfusion and thus organ-like functions. To this end, microfluidic systems enable construction of cell culture devices which can be designed to more closely resemble the smallest functional unit of organs. Multiphysics simulations represent a powerful tool to study the various relevant physical phenomena and their impact on functionality inside microfluidic structures. This is particularly useful as it allows for assessment of system functions already during the design stage prior to actual chip fabrication. In the HepaChip®, dielectrophoretic forces are used to assemble human hepatocytes and human endothelial cells in liver sinusoid-like structures. Numerical simulations of flow distribution, shear stress, electrical fields and heat dissipation inside the cell assembly chambers as well as surface wetting and surface tension effects during filling of the microchannel network supported the design of this human-liver-on-chip microfluidic system for cell culture applications. Based on the device design resulting thereof, a prototype chip was injection-moulded in COP (cyclic olefin polymer). Functional hepatocyte and endothelial cell cocultures were established inside the HepaChip® showing excellent metabolic and secretory performance.

  11. Application of Large Eddy Simulation in the process of the Multi-Physics Field Coupling in a Combustion Chamber

    Directory of Open Access Journals (Sweden)

    Xu Rang-Shu

    2015-01-01

    Full Text Available Numerical simulation is the main method to solve turbulence problems. As one of the three methods which are commonly used in large-eddy simulation model (LES is the most effective and promising research method. The basic idea of large-eddy simulation is that the large scale turbulent motion is directly simulated and we use the sub-grid scale model to simulate small-scale turbulent motion. Continuing alternative load exists in aero-engine combustion chamber during operation. This coupling phenomenon is an important reason to the combustion chamber fatigue failure. In this paper, the large-eddy simulation methods are described and applied in researching aero-engine combustion chamber multi-physics field coupling analysis. By comparing with the experimental results we verify the feasibility of this method and there is great significance of actual project.

  12. Coupled Multi-physical Simulations for the Assessment of Nuclear Waste Repository Concepts: Modeling, Software Development and Simulation

    Science.gov (United States)

    Massmann, J.; Nagel, T.; Bilke, L.; Böttcher, N.; Heusermann, S.; Fischer, T.; Kumar, V.; Schäfers, A.; Shao, H.; Vogel, P.; Wang, W.; Watanabe, N.; Ziefle, G.; Kolditz, O.

    2016-12-01

    As part of the German site selection process for a high-level nuclear waste repository, different repository concepts in the geological candidate formations rock salt, clay stone and crystalline rock are being discussed. An open assessment of these concepts using numerical simulations requires physical models capturing the individual particularities of each rock type and associated geotechnical barrier concept to a comparable level of sophistication. In a joint work group of the Helmholtz Centre for Environmental Research (UFZ) and the German Federal Institute for Geosciences and Natural Resources (BGR), scientists of the UFZ are developing and implementing multiphysical process models while BGR scientists apply them to large scale analyses. The advances in simulation methods for waste repositories are incorporated into the open-source code OpenGeoSys. Here, recent application-driven progress in this context is highlighted. A robust implementation of visco-plasticity with temperature-dependent properties into a framework for the thermo-mechanical analysis of rock salt will be shown. The model enables the simulation of heat transport along with its consequences on the elastic response as well as on primary and secondary creep or the occurrence of dilatancy in the repository near field. Transverse isotropy, non-isothermal hydraulic processes and their coupling to mechanical stresses are taken into account for the analysis of repositories in clay stone. These processes are also considered in the near field analyses of engineered barrier systems, including the swelling/shrinkage of the bentonite material. The temperature-dependent saturation evolution around the heat-emitting waste container is described by different multiphase flow formulations. For all mentioned applications, we illustrate the workflow from model development and implementation, over verification and validation, to repository-scale application simulations using methods of high performance computing.

  13. Multi-Physics Modelling of Fault Mechanics Using REDBACK: A Parallel Open-Source Simulator for Tightly Coupled Problems

    Science.gov (United States)

    Poulet, Thomas; Paesold, Martin; Veveakis, Manolis

    2017-03-01

    Faults play a major role in many economically and environmentally important geological systems, ranging from impermeable seals in petroleum reservoirs to fluid pathways in ore-forming hydrothermal systems. Their behavior is therefore widely studied and fault mechanics is particularly focused on the mechanisms explaining their transient evolution. Single faults can change in time from seals to open channels as they become seismically active and various models have recently been presented to explain the driving forces responsible for such transitions. A model of particular interest is the multi-physics oscillator of Alevizos et al. (J Geophys Res Solid Earth 119(6), 4558-4582, 2014) which extends the traditional rate and state friction approach to rate and temperature-dependent ductile rocks, and has been successfully applied to explain spatial features of exposed thrusts as well as temporal evolutions of current subduction zones. In this contribution we implement that model in REDBACK, a parallel open-source multi-physics simulator developed to solve such geological instabilities in three dimensions. The resolution of the underlying system of equations in a tightly coupled manner allows REDBACK to capture appropriately the various theoretical regimes of the system, including the periodic and non-periodic instabilities. REDBACK can then be used to simulate the drastic permeability evolution in time of such systems, where nominally impermeable faults can sporadically become fluid pathways, with permeability increases of several orders of magnitude.

  14. Modeling and simulation of heat sinks for computer processors in COMSOL Multiphysics

    OpenAIRE

    2012-01-01

    In this study, the heat transfer of three desktop- computer heat sinks was analyzed. The objective of using these heat sinks is to avoid overheating of the computer’s processing unit and in turn reduce the corresponding loss in the unit’s service time. The heat sinks were modeled using COMSOL Multiphysics with the actual dimensions of the devices, and heat generation was modeled with a point source. In the next step, the heat sink designs were modified to achieve a lower temperature in the hi...

  15. An Efficient Upscaling Process Based on a Unified Fine-scale Multi-Physics Model for Flow Simulation in Naturally Fracture Carbonate Karst Reservoirs

    KAUST Repository

    Bi, Linfeng

    2009-01-01

    The main challenges in modeling fluid flow through naturally-fractured carbonate karst reservoirs are how to address various flow physics in complex geological architectures due to the presence of vugs and caves which are connected via fracture networks at multiple scales. In this paper, we present a unified multi-physics model that adapts to the complex flow regime through naturally-fractured carbonate karst reservoirs. This approach generalizes Stokes-Brinkman model (Popov et al. 2007). The fracture networks provide the essential connection between the caves in carbonate karst reservoirs. It is thus very important to resolve the flow in fracture network and the interaction between fractures and caves to better understand the complex flow behavior. The idea is to use Stokes-Brinkman model to represent flow through rock matrix, void caves as well as intermediate flows in very high permeability regions and to use an idea similar to discrete fracture network model to represent flow in fracture network. Consequently, various numerical solution strategies can be efficiently applied to greatly improve the computational efficiency in flow simulations. We have applied this unified multi-physics model as a fine-scale flow solver in scale-up computations. Both local and global scale-up are considered. It is found that global scale-up has much more accurate than local scale-up. Global scale-up requires the solution of global flow problems on fine grid, which generally is computationally expensive. The proposed model has the ability to deal with large number of fractures and caves, which facilitate the application of Stokes-Brinkman model in global scale-up computation. The proposed model flexibly adapts to the different flow physics in naturally-fractured carbonate karst reservoirs in a simple and effective way. It certainly extends modeling and predicting capability in efficient development of this important type of reservoir.

  16. Enabling Predictive Simulation and UQ of Complex Multiphysics PDE Systems by the Development of Goal-Oriented Variational Sensitivity Analysis and a-Posteriori Error Estimation Methods

    Energy Technology Data Exchange (ETDEWEB)

    Estep, Donald [Colorado State Univ., Fort Collins, CO (United States)

    2015-11-30

    This project addressed the challenge of predictive computational analysis of strongly coupled, highly nonlinear multiphysics systems characterized by multiple physical phenomena that span a large range of length- and time-scales. Specifically, the project was focused on computational estimation of numerical error and sensitivity analysis of computational solutions with respect to variations in parameters and data. In addition, the project investigated the use of accurate computational estimates to guide efficient adaptive discretization. The project developed, analyzed and evaluated new variational adjoint-based techniques for integration, model, and data error estimation/control and sensitivity analysis, in evolutionary multiphysics multiscale simulations.

  17. Mechanical behavior simulation of MEMS-based cantilever beam using COMSOL multiphysics

    Science.gov (United States)

    Acheli, A.; Serhane, R.

    2015-03-01

    This paper presents the studies of mechanical behavior of MEMS cantilever beam made of poly-silicon material, using the coupling of three application modes (plane strain, electrostatics and the moving mesh) of COMSOL Multi-physics software. The cantilevers playing a key role in Micro Electro-Mechanical Systems (MEMS) devices (switches, resonators, etc) working under potential shock. This is why they require actuation under predetermined conditions, such as electrostatic force or inertial force. In this paper, we present mechanical behavior of a cantilever actuated by an electrostatic force. In addition to the simplification of calculations, the weight of the cantilever was not taken into account. Different parameters like beam displacement, electrostatics force and stress over the beam have been calculated by finite element method after having defining the geometry, the material of the cantilever model (fixed at one of ends but is free to move otherwise) and his operational space.

  18. Mechanical behavior simulation of MEMS-based cantilever beam using COMSOL multiphysics

    Energy Technology Data Exchange (ETDEWEB)

    Acheli, A., E-mail: aacheli@cdta.dz; Serhane, R. [Centre de Développement des Technologies Avancées (CDTA). BP n°17 Baba Hassen, Alger (Algeria)

    2015-03-30

    This paper presents the studies of mechanical behavior of MEMS cantilever beam made of poly-silicon material, using the coupling of three application modes (plane strain, electrostatics and the moving mesh) of COMSOL Multi-physics software. The cantilevers playing a key role in Micro Electro-Mechanical Systems (MEMS) devices (switches, resonators, etc) working under potential shock. This is why they require actuation under predetermined conditions, such as electrostatic force or inertial force. In this paper, we present mechanical behavior of a cantilever actuated by an electrostatic force. In addition to the simplification of calculations, the weight of the cantilever was not taken into account. Different parameters like beam displacement, electrostatics force and stress over the beam have been calculated by finite element method after having defining the geometry, the material of the cantilever model (fixed at one of ends but is free to move otherwise) and his operational space.

  19. Evaluation of a transient, simultaneous, arbitrary Lagrange-Euler based multi-physics method for simulating the mitral heart valve.

    Science.gov (United States)

    Espino, Daniel M; Shepherd, Duncan E T; Hukins, David W L

    2014-01-01

    A transient multi-physics model of the mitral heart valve has been developed, which allows simultaneous calculation of fluid flow and structural deformation. A recently developed contact method has been applied to enable simulation of systole (the stage when blood pressure is elevated within the heart to pump blood to the body). The geometry was simplified to represent the mitral valve within the heart walls in two dimensions. Only the mitral valve undergoes deformation. A moving arbitrary Lagrange-Euler mesh is used to allow true fluid-structure interaction (FSI). The FSI model requires blood flow to induce valve closure by inducing strains in the region of 10-20%. Model predictions were found to be consistent with existing literature and will undergo further development.

  20. Multiphysics simulation for the optimization of optical nanoantennas working as distributed bolometers in the infrared

    Science.gov (United States)

    Cuadrado, Alexander; Alda, Javier; González, Francisco Javier

    2013-01-01

    The electric currents induced by infrared radiation incident on optical antennas and resonant structures increase their temperature through Joule heating as well as change their electric resistance through the bolometric effect. As the thermo-electric mechanism exists throughout a distributed bolometer, a multiphysics approach was adopted to analyze thermal, electrical, and electromagnetic effects in a dipole antenna functioning as a resonant distributed bolometer. The finite element method was used for electromagnetic and thermal considerations. The results showed that bolometric performance depends on the choice of materials, the geometry of the resonant structure, the thickness of an insulating layer, and the characteristics of a bias circuit. Materials with large skin depth and small thermal conductivity are desirable. The thickness of the SiO insulating layer should not exceed 1.2 μm, and a current source for the bias circuit enhances performance. An optimized device designed with the previously stated design rules provides a response increase of two orders of magnitude compared to previously reported devices using the same dipole geometry.

  1. Radio Frequency Simulation System (RFSS) Capabilities Summary

    Science.gov (United States)

    1977-04-01

    S- 0LEVEL-- TECHNICAL REPORT TD -77-8 RADIO FREQUENCY SIMULATION SYSTEM (RFSS) CAPABILITIES SUMMARY 00 SAeroballistios Directorate Advanced Simulation...gAttn: DRDMT - TD /AMCMS 63 303.214131101 RedstngArj gUAl. Alabmt 35809______________ It CONTITL.uNG OFFICE NAME AND ADDRESS CoMuaa ner US Army Missile...r ~- -- 0 0 0 1 N -4 -- -~ *5 0 - 5e41 -A I: a 00 I I. S Jto cc iI us V A U. II I’~z’LF~iJ - - - - -> 3-cc dc -4 -.40 =! Jo -AZC 4 C - 442q 0 M~A $Ji a

  2. A program code generator for multiphysics biological simulation using markup languages.

    Science.gov (United States)

    Amano, Akira; Kawabata, Masanari; Yamashita, Yoshiharu; Rusty Punzalan, Florencio; Shimayoshi, Takao; Kuwabara, Hiroaki; Kunieda, Yoshitoshi

    2012-01-01

    To cope with the complexity of the biological function simulation models, model representation with description language is becoming popular. However, simulation software itself becomes complex in these environment, thus, it is difficult to modify the simulation conditions, target computation resources or calculation methods. In the complex biological function simulation software, there are 1) model equations, 2) boundary conditions and 3) calculation schemes. Use of description model file is useful for first point and partly second point, however, third point is difficult to handle for various calculation schemes which is required for simulation models constructed from two or more elementary models. We introduce a simulation software generation system which use description language based description of coupling calculation scheme together with cell model description file. By using this software, we can easily generate biological simulation code with variety of coupling calculation schemes. To show the efficiency of our system, example of coupling calculation scheme with three elementary models are shown.

  3. Numerical rainfall simulation with different spatial and temporal evenness by using a WRF multiphysics ensemble

    Science.gov (United States)

    Tian, Jiyang; Liu, Jia; Yan, Denghua; Li, Chuanzhe; Yu, Fuliang

    2017-04-01

    The Weather Research and Forecasting (WRF) model is used in this study to simulate six storm events in two semi-humid catchments of northern China. The six storm events are classified into four types based on the rainfall evenness in the spatial and temporal dimensions. Two microphysics, two planetary boundary layers (PBL) and three cumulus parameterizations are combined to develop an ensemble containing 16 members for rainfall generation. The WRF model performs the best for type 1 events with relatively even distributions of rainfall in both space and time. The average relative error (ARE) for the cumulative rainfall amount is 15.82 %. For the spatial rainfall simulation, the lowest root mean square error (RMSE) is found with event II (0.4007), which has the most even spatial distribution, and for the temporal simulation the lowest RMSE is found with event I (1.0218), which has the most even temporal distribution. The most difficult to reproduce are found to be the very convective storms with uneven spatiotemporal distributions (type 4 event), and the average relative error for the cumulative rainfall amounts is up to 66.37 %. The RMSE results of event III, with the most uneven spatial and temporal distribution, are 0.9688 for the spatial simulation and 2.5327 for the temporal simulation, which are much higher than the other storms. The general performance of the current WRF physical parameterizations is discussed. The Betts-Miller-Janjic (BMJ) scheme is found to be unsuitable for rainfall simulation in the study sites. For type 1, 2 and 4 storms, member 4 performs the best. For type 3 storms, members 5 and 7 are the better choice. More guidance is provided for choosing among the physical parameterizations for accurate rainfall simulations of different storm types in the study area.

  4. Simulating European heatwaves with WRF - a multi-physics ensemble approach

    Science.gov (United States)

    Stegehuis, Annemiek; Vautard, Robert; Ciais, Philippe; Teuling, Ryan

    2014-05-01

    There is a need to simulate mega heatwaves as impacts are large and they are expected to become more frequent in the future. Current climate models are calibrated on the current climate without such impacting events. Studies with model ensembles have been done, but less with physics ensembles. Here we investigate what physics are suitable to simulate the heatwaves of 2003 (Europe) and 2010 (Russia) with WRF, a regional climate model. We run the model over 200 times with different combinations of physics. We find that only few combinations can simulate the observed temperatures during the heatwaves, but also during a normal summer. Monthly precipitation is mostly overestimated, while the observations of monthly global European radiation lay on average in the middle of the model simulations. Most of the variation between simulations is due to the convection scheme. We rank all runs based on observed temperature, precipitation and radiation. The 5 best performing runs are also tested for other regions and variables. In our opinion these physic combinations can best be used to perform further heatwave analysis when using WRF.

  5. Parallel object-oriented algorithms for simulation of multiphysics : application to thermal systems

    OpenAIRE

    López Mas, Joan

    2016-01-01

    The present and the future expectation in parallel computing pose a new generational change in simulation and computing. Modern High Performance Computing (HPC) facilities have high computational power in terms of operations per second -today peta-FLOPS (10e15 FLOPS) and growing toward the exascale (10e18 FLOPS) which is expected in few years-. This opens the way for using simulation tools in a wide range of new engineering and scientific applications. For example, CFD&HT codes will be eff...

  6. Results from Tight and Loose Coupled Multiphysics in Nuclear Fuels Performance Simulations using BISON

    Energy Technology Data Exchange (ETDEWEB)

    S. R. Novascone; B. W. Spencer; D. Andrs; R. L. Williamson; J. D. Hales; D. M. Perez

    2013-05-01

    The behavior of nuclear fuel in the reactor environment is affected by multiple physics, most notably heat conduction and solid mechanics, which can have a strong influence on each other. To provide credible solutions, a fuel performance simulation code must have the ability to obtain solutions for each of the physics, including coupling between them. Solution strategies for solving systems of coupled equations can be categorized as loosely-coupled, where the individual physics are solved separately, keeping the solutions for the other physics fixed at each iteration, or tightly coupled, where the nonlinear solver simultaneously drives down the residual for each physics, taking into account the coupling between the physics in each nonlinear iteration. In this paper, we compare the performance of loosely and tightly coupled solution algorithms for thermomechanical problems involving coupled thermal and mechanical contact, which is a primary source of interdependence between thermal and mechanical solutions in fuel performance models. The results indicate that loosely-coupled simulations require significantly more nonlinear iterations, and may lead to convergence trouble when the thermal conductivity of the gap is too small. We also apply the tightly coupled solution strategy to a nuclear fuel simulation of an experiment in a test reactor. Studying the results from these simulations indicates that perhaps convergence for either approach may be problem dependent, i.e., there may be problems for which a loose coupled approach converges, where tightly coupled won’t converge and vice versa.

  7. Multiphysics multi-model simulation of large-area plasma chemical reactors

    NARCIS (Netherlands)

    Krzhizhanovskaya, V.; Ivanov, D.; Gorbachev, Y.; Smirnov, A.

    2010-01-01

    Facing an ever-growing demand for large-area solar cells and flat-panel displays, the industry strives to produce larger, cheaper and better performing thin films. Computer simulation has proved to be a reliable and cost-efficient way to optimize existing technologies, to develop and test new ideas.

  8. Multiphysics multi-model simulation of large-area plasma chemical reactors

    NARCIS (Netherlands)

    V. Krzhizhanovskaya; D. Ivanov; Y. Gorbachev; A. Smirnov

    2009-01-01

    Facing an ever-growing demand for large-area solar cells and flat-panel displays, the industry strives to produce larger, cheaper and better performing thin films. Computer simulation has proved to be a reliable and cost-efficient way to optimize existing technologies, to develop and test new ideas.

  9. High-fidelity multiphysics simulation of BWR assembly with coupled TORT-TD/CTF

    Energy Technology Data Exchange (ETDEWEB)

    Magedanz, J. [Dept. of Mechanical and Nuclear Engineering, Pennsylvania State Univ., Reber Building, Univ. Park, PA 16802 (United States); Perin, Y. [Gesellschaft fuer Anlagen- und Reaktorsicherheit GRS mbH, Forschungsinstitute, D-85748 Garching (Germany); Avramova, M. [Dept. of Mechanical and Nuclear Engineering, Pennsylvania State Univ., Reber Building, Univ. Park, PA 16802 (United States); Pautz, A.; Puente-Espel, F.; Seubert, A.; Sureda, A.; Velkov, K.; Zwermann, W. [Gesellschaft fuer Anlagen- und Reaktorsicherheit GRS mbH, Forschungsinstitute, D-85748 Garching (Germany)

    2012-07-01

    This paper describes the application of the coupled codes TORT-TD and CTF to the pin-by-pin modeling of a BWR fuel assembly with thermal-hydraulic feedback. TORT-TD, developed at GRS, is a time-dependent three dimensional discrete ordinates code. CTF is the PSU's improved version of the subchannel code COBRA-TF, which uses a two-fluid, three-field model to represent two-phase flow with entrained droplets, and is commonly applied to evaluate LWR safety margins. The coupled codes system TORT-TD/CTF, already applied to several PWR cases involving MOX, was adapted from PWR to BWR applications. The purpose of the research described in this paper is to verify the coupling for modeling two-phase flow at the pin cell level. Using an ATRIUM-10 assembly, the system's steady-state capabilities were tested on two cases: one without control blade insertion and another with partially inserted blades. The influence of the neutron absorber on local axial and radial parameters is presented. The description of an inlet flow reduction transient is an example for the time-dependent capability of the coupled system. (authors)

  10. Scalable Methods for Uncertainty Quantification, Data Assimilation and Target Accuracy Assessment for Multi-Physics Advanced Simulation of Light Water Reactors

    Science.gov (United States)

    Khuwaileh, Bassam

    High fidelity simulation of nuclear reactors entails large scale applications characterized with high dimensionality and tremendous complexity where various physics models are integrated in the form of coupled models (e.g. neutronic with thermal-hydraulic feedback). Each of the coupled modules represents a high fidelity formulation of the first principles governing the physics of interest. Therefore, new developments in high fidelity multi-physics simulation and the corresponding sensitivity/uncertainty quantification analysis are paramount to the development and competitiveness of reactors achieved through enhanced understanding of the design and safety margins. Accordingly, this dissertation introduces efficient and scalable algorithms for performing efficient Uncertainty Quantification (UQ), Data Assimilation (DA) and Target Accuracy Assessment (TAA) for large scale, multi-physics reactor design and safety problems. This dissertation builds upon previous efforts for adaptive core simulation and reduced order modeling algorithms and extends these efforts towards coupled multi-physics models with feedback. The core idea is to recast the reactor physics analysis in terms of reduced order models. This can be achieved via identifying the important/influential degrees of freedom (DoF) via the subspace analysis, such that the required analysis can be recast by considering the important DoF only. In this dissertation, efficient algorithms for lower dimensional subspace construction have been developed for single physics and multi-physics applications with feedback. Then the reduced subspace is used to solve realistic, large scale forward (UQ) and inverse problems (DA and TAA). Once the elite set of DoF is determined, the uncertainty/sensitivity/target accuracy assessment and data assimilation analysis can be performed accurately and efficiently for large scale, high dimensional multi-physics nuclear engineering applications. Hence, in this work a Karhunen-Loeve (KL

  11. Multi-scale and multi-physics simulations using the multi-fluid plasma model

    Science.gov (United States)

    2017-04-25

    F ∂x = S The source Jacobian ∂S ∂Q has imaginary eigenvalues The equation system has dispersive sources The dispersion is physical (may be...ADDRESS(ES) 12. DISTRIBUTION/AVAILABILITY STATEMENT 13. SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: a...NUMBER (Include area code) 25 April 2017 Briefing Charts 01 April 2017 - 30 April 2017 Multi-scale and multi- physics simulations using the multi

  12. Methodology Development for Passive Component Reliability Modeling in a Multi-Physics Simulation Environment

    Energy Technology Data Exchange (ETDEWEB)

    Aldemir, Tunc [The Ohio State Univ., Columbus, OH (United States); Denning, Richard [The Ohio State Univ., Columbus, OH (United States); Catalyurek, Umit [The Ohio State Univ., Columbus, OH (United States); Unwin, Stephen [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-01-23

    Reduction in safety margin can be expected as passive structures and components undergo degradation with time. Limitations in the traditional probabilistic risk assessment (PRA) methodology constrain its value as an effective tool to address the impact of aging effects on risk and for quantifying the impact of aging management strategies in maintaining safety margins. A methodology has been developed to address multiple aging mechanisms involving large numbers of components (with possibly statistically dependent failures) within the PRA framework in a computationally feasible manner when the sequencing of events is conditioned on the physical conditions predicted in a simulation environment, such as the New Generation System Code (NGSC) concept. Both epistemic and aleatory uncertainties can be accounted for within the same phenomenological framework and maintenance can be accounted for in a coherent fashion. The framework accommodates the prospective impacts of various intervention strategies such as testing, maintenance, and refurbishment. The methodology is illustrated with several examples.

  13. Numerical simulation of mechatronic sensors and actuators finite elements for computational multiphysics

    CERN Document Server

    Kaltenbacher, Manfred

    2015-01-01

    Like the previous editions also the third edition of this book combines the detailed physical modeling of mechatronic systems and their precise numerical simulation using the Finite Element (FE) method. Thereby, the basic chapter concerning the Finite Element (FE) method is enhanced, provides now also a description of higher order finite elements (both for nodal and edge finite elements) and a detailed discussion of non-conforming mesh techniques. The author enhances and improves many discussions on principles and methods. In particular, more emphasis is put on the description of single fields by adding the flow field. Corresponding to these field, the book is augmented with the new chapter about coupled flow-structural mechanical systems. Thereby, the discussion of computational aeroacoustics is extended towards perturbation approaches, which allows a decomposition of flow and acoustic quantities within the flow region. Last but not least, applications are updated and restructured so that the book meets mode...

  14. New results on structure of low beta confinement Polywell cusps simulated by comsol multiphysics

    Science.gov (United States)

    Mahdavipour, B.; Salar Elahi, A.

    The Inertial electrostatic confinement (IEC) is one of the ways for fusion approaches. It is one of the various methods which can be used to confine hot fusion plasma. The advantage of IEC is that the IEC experiments could be done in smaller size facilities than ITER or NIF, costing less money and moving forward faster. In IEC fusion, we need to trap adequate electrons to confine the desired ion density which is needed for a fusion reactor. Polywell is a device which uses the magnetic cusp system and traps the required amount of electrons for fusion reactions. The purpose of this device is to create a virtual cathode in order to achieve nuclear fusion using inertial electrostatic confinement (Miley and Krupakar Murali, 2014). In this paper, we have simulated the low beta Polywell. Then, we examined the effects of coil spacing, coils current, electron injection energy on confinement time.

  15. Analysis of Annular Thermoelectric Couples with Nonuniform Temperature Distribution by Means of 3-D Multiphysics Simulation

    Science.gov (United States)

    Bauknecht, Andreas; Steinert, Torsten; Spengler, Carsten; Suck, Gerrit

    2013-07-01

    Thermoelectric (TE) modules with annular geometry are very attractive for waste heat recovery within the automotive world, especially when integrated as stacks into tubular heat exchangers. The required temperature difference is built up between the coolant, which flows inside an inner tube, and the exhaust gas, which flows around an outer tube. The flow pattern of the exhaust gas can be axial or circumferential, which can lead to higher heat transfer coefficients on the outer surface of the tube. However, this multidimensional construction in combination with a complex flow pattern can lead to a nonuniform heat flux. Additionally, the system experiences a nonuniform temperature distribution which consequently leads to complex conditions regarding the electrical potential. The relevant effects are investigated using a three-dimensional (3-D) numerical model implemented in the computational fluid dynamics (CFD) simulation environment Star-CCM+. The model supports temperature-dependent characteristics of the materials, contact resistances, and parasitic effects in the TE module. Furthermore, it involves techniques to quickly find the exact maximum power point of the TE module with the given boundary conditions. Using the validated model the influence of the nonuniform temperature distribution is investigated with emphasis on the electrical output and TE efficiency.

  16. Modelación y simulación de disipadores de calor para procesadores de computadora en COMSOL Multiphysics Modeling and simulation of heat sinks for computer processors in COMSOL Multiphysics

    Directory of Open Access Journals (Sweden)

    Sulin Garro Acón

    2012-11-01

    Full Text Available En este estudio se analizó la transferencia de calor en tres disipadores de calor utilizados para enfriar los procesadores de computadoras de escritorio. El objetivo de estos disipadores es evitar el sobrecalentamiento de la unidad de procesamiento y la consecuente reducción de la vida útil del computador. Los disipadores de calor se modelaron usando COMSOL Multiphysics con las dimensiones reales de los dispositivos y la generación de calor se modeló con una fuente puntual. Luego se modificaron los diseños de los disipadores para lograr una temperatura más baja en la zona más caliente del procesador. El resultado fue una reducción en la temperatura en el rango de 5-78 grados Kelvin, al rediseñarse el disipador de calor con variaciones feasibles como la reducción del grosor de las placas de intercambio de calor y el aumento de su número. Esto demuestra la posibilidad de desarrollar diseños optimizados para disipadores de calor que no requieran más materiales sino una mejor ingeniería. El trabajo se inició como parte del curso CM-4101 Modelización y Simulación.In this study, the heat transfer of three desktop- computer heat sinks was analyzed. The objective of using these heat sinks is to avoid overheating of the computer’s processing unit and in turn reduce the corresponding loss in the unit’s service time. The heat sinks were modeled using COMSOL Multiphysics with the actual dimensions of the devices, and heat generation was modeled with a point source. In the next step, the heat sink designs were modified to achieve a lower temperature in the higher temperature location on the heat sink. The results were temperature reductions in the range of 5-78 degrees Kelvin, by making feasible variations in design such as reducing the thickness of the heat exchanger fins and increasing their number. This paper demonstrates that there is room to develop improved designs that do not require more materials but rather a better engineering

  17. Multi-physics simulation and fabrication of a compact 128 × 128 micro-electro-mechanical system Fabry-Perot cavity tunable filter array for infrared hyperspectral imager.

    Science.gov (United States)

    Meng, Qinghua; Chen, Sihai; Lai, Jianjun; Huang, Ying; Sun, Zhenjun

    2015-08-01

    This paper demonstrates the design and fabrication of a 128×128 micro-electro-mechanical systems Fabry-Perot (F-P) cavity filter array, which can be applied for the hyperspectral imager. To obtain better mechanical performance of the filters, F-P cavity supporting structures are analyzed by multi-physics finite element modeling. The simulation results indicate that Z-arm is the key component of the structure. The F-P cavity array with Z-arm structures was also fabricated. The experimental results show excellent parallelism of the bridge deck, which agree with the simulation results. A conclusion is drawn that Z-arm supporting structures are important to hyperspectral imaging system, which can achieve a large tuning range and high fill factor compared to straight arm structures. The filter arrays have the potential to replace the traditional dispersive element.

  18. Effect of patterning on the performance of p-type Cu2O TFTs: a 3D simulation using COMSOL multiphysics

    Science.gov (United States)

    Alsharif, Sarah; Farhan, Hanaa; Al-Jawhari, Hala

    2017-01-01

    A 3D model for p-type Cu2O thin-film transistor (TFT) was simulated for the first time using COMSOL Multiphysics. The main objective of this modeling is to investigate the effect of patterning either the channel or the gate on the performance of Cu2O TFTs. Considering the ideal case, where traps and leakage current are not incorporated, we compared the performance of three different designs; unpatterned, patterned channel and patterned channel and gate TFTs. In each case, the transfer curve, output characteristics, current flow and potential distribution were clarified. The comparison between main parameters showed that the unpatterned model overestimated the field effect mobility µFE by 37.4% over the fully patterned TFT, nevertheless, the latter exhibited the highest on/off current ratio and the lowest off-current. A simulation of experimental output characteristics reported for Cu2O TFT was performed to check the model viability.

  19. Advanced Modeling, Simulation and Analysis (AMSA) Capability Roadmap Progress Review

    Science.gov (United States)

    Antonsson, Erik; Gombosi, Tamas

    2005-01-01

    Contents include the following: NASA capability roadmap activity. Advanced modeling, simulation, and analysis overview. Scientific modeling and simulation. Operations modeling. Multi-special sensing (UV-gamma). System integration. M and S Environments and Infrastructure.

  20. Integration of Advanced Probabilistic Analysis Techniques with Multi-Physics Models

    Energy Technology Data Exchange (ETDEWEB)

    Cetiner, Mustafa Sacit; none,; Flanagan, George F. [ORNL; Poore III, Willis P. [ORNL; Muhlheim, Michael David [ORNL

    2014-07-30

    An integrated simulation platform that couples probabilistic analysis-based tools with model-based simulation tools can provide valuable insights for reactive and proactive responses to plant operating conditions. The objective of this work is to demonstrate the benefits of a partial implementation of the Small Modular Reactor (SMR) Probabilistic Risk Assessment (PRA) Detailed Framework Specification through the coupling of advanced PRA capabilities and accurate multi-physics plant models. Coupling a probabilistic model with a multi-physics model will aid in design, operations, and safety by providing a more accurate understanding of plant behavior. This represents the first attempt at actually integrating these two types of analyses for a control system used for operations, on a faster than real-time basis. This report documents the development of the basic communication capability to exchange data with the probabilistic model using Reliability Workbench (RWB) and the multi-physics model using Dymola. The communication pathways from injecting a fault (i.e., failing a component) to the probabilistic and multi-physics models were successfully completed. This first version was tested with prototypic models represented in both RWB and Modelica. First, a simple event tree/fault tree (ET/FT) model was created to develop the software code to implement the communication capabilities between the dynamic-link library (dll) and RWB. A program, written in C#, successfully communicates faults to the probabilistic model through the dll. A systems model of the Advanced Liquid-Metal Reactor–Power Reactor Inherently Safe Module (ALMR-PRISM) design developed under another DOE project was upgraded using Dymola to include proper interfaces to allow data exchange with the control application (ConApp). A program, written in C+, successfully communicates faults to the multi-physics model. The results of the example simulation were successfully plotted.

  1. A Comparison of Simulation Capabilities for Ducts

    Energy Technology Data Exchange (ETDEWEB)

    Miller, William A [ORNL; Smith, Matt K [ORNL; Gu, Lixing [Florida Solar Energy Center (FSEC); New, Joshua Ryan [ORNL

    2014-11-01

    Typically, the cheapest way to install a central air conditioning system in residential buildings is to place the ductwork in the attic. Energy losses due to duct-attic interactions can be great, but current whole-house models are unable to capture the dynamic multi-mode physics of the interactions. The building industry is notoriously fragmented and unable to devote adequate research resources to solve this problem. Builders are going to continue to put ducts in the attic because floor space is too expensive to closet them within living space, and there are both construction and aesthetic issues with other approaches such as dropped ceilings. Thus, there is a substantial need to publicly document duct losses and the cost of energy used by ducts in attics so that practitioners, builders, homeowners and state and federal code officials can make informed decisions leading to changes in new construction and additional retrofit actions. Thus, the goal of this study is to conduct a comparison of AtticSim and EnergyPlus simulation algorithms to identify specific features for potential inclusion in EnergyPlus that would allow higher-fidelity modeling of HVAC operation and duct transport of conditioned air. It is anticipated that the resulting analysis from these simulation tools will inform energy decisions relating to the role of ducts in future building energy codes and standards.

  2. Implementation of On-the-Fly Doppler Broadening in MCNP5 for Multiphysics Simulation of Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    William Martin

    2012-11-16

    A new method to obtain Doppler broadened cross sections has been implemented into MCNP, removing the need to generate cross sections for isotopes at problem temperatures. Previous work had established the scientific feasibility of obtaining Doppler-broadened cross sections "on-the-fly" (OTF) during the random walk of the neutron. Thus, when a neutron of energy E enters a material region that is at some temperature T, the cross sections for that material at the exact temperature T are immediately obtained by interpolation using a high order functional expansion for the temperature dependence of the Doppler-broadened cross section for that isotope at the neutron energy E. A standalone Fortran code has been developed that generates the OTF library for any isotope that can be processed by NJOY. The OTF cross sections agree with the NJOY-based cross sections for all neutron energies and all temperatures in the range specified by the user, e.g., 250K - 3200K. The OTF methodology has been successfully implemented into the MCNP Monte Carlo code and has been tested on several test problems by comparing MCNP with conventional ACE cross sections versus MCNP with OTF cross sections. The test problems include the Doppler defect reactivity benchmark suite and two full-core VHTR configurations, including one with multiphysics coupling using RELAP5-3D/ATHENA for the thermal-hydraulic analysis. The comparison has been excellent, verifying that the OTF libraries can be used in place of the conventional ACE libraries generated at problem temperatures. In addition, it has been found that using OTF cross sections greatly reduces the complexity of the input for MCNP, especially for full-core temperature feedback calculations with many temperature regions. This results in an order of magnitude decrease in the number of input lines for full-core configurations, thus simplifying input preparation and reducing the potential for input errors. Finally, for full-core problems with multiphysics

  3. Modelación y simulación de disipadores de calor para procesadores de computadora en COMSOL Multiphysics Modeling and simulation of heat sinks for computer processors in COMSOL Multiphysics

    OpenAIRE

    2012-01-01

    En este estudio se analizó la transferencia de calor en tres disipadores de calor utilizados para enfriar los procesadores de computadoras de escritorio. El objetivo de estos disipadores es evitar el sobrecalentamiento de la unidad de procesamiento y la consecuente reducción de la vida útil del computador. Los disipadores de calor se modelaron usando COMSOL Multiphysics con las dimensiones reales de los dispositivos y la generación de calor se modeló con una fuente puntual. Luego se modificar...

  4. Multiphysics modeling of magnetorheological dampers

    Directory of Open Access Journals (Sweden)

    D Case

    2016-09-01

    Full Text Available The dynamics of a small scale magnetorheological damper were modeled and analyzed using multiphysics commercial finite element software to couple the electromagnetic field distribution with the non-Newtonian fluid flow. The magnetic flux lines and field intensity generated within the damper and cyclic fluid flow in the damper under harmonic motion were simulated with the AC/DC and CFD physics modules of COMSOL Multiphysics, respectively. Coupling of the physics is achieved through a modified Bingham plastic definition, relating the fluid's dynamic viscosity to the intensity of the induced magnetic field. Good agreement is confirmed between simulation results and experimentally observed resistance forces in the damper. This study was conducted to determine the feasibility of utilizing magnetorheological dampers in a medical orthosis for pathological tremor attenuation. The implemented models are thus dimensioned on a relatively small scale. The method used, however, is not specific to the damper's size or geometry and can be extended to larger-scale devices with little or no complication.

  5. Simulation About the Growth of Chinese Firm's Safety Management Capability

    Institute of Scientific and Technical Information of China (English)

    LIU Tie-zhong; LI Zhi-xiang

    2008-01-01

    Aiming at the deficiency of exterminating measures of Chinese firm safety management,a simulation model of Chinese firm's safety management capability based on the organizational learning theory,in which the simulation method of system dynamics is utilized.The level variable and rate vailable are designed based on the practical situation and change situation of corresponding variables of firm's safety management capability.Simulation firms are built with accident ease groups of the oil industry,chemieal industry,machine industry,coal mining industry,and weapon industry.Through analyzing the simulation result,the growth law of Chinese firm's safety management capability is obtained as follows:the accumulating and the coupling of safety knowledge should be emphasized at the same time;the balance of learning behavior of individual,group and organization should be considered together;different types of Chinese firm should take different safety policies according to their practical situations.

  6. A theory manual for multi-physics code coupling in LIME.

    Energy Technology Data Exchange (ETDEWEB)

    Belcourt, Noel; Bartlett, Roscoe Ainsworth; Pawlowski, Roger Patrick; Schmidt, Rodney Cannon; Hooper, Russell Warren

    2011-03-01

    The Lightweight Integrating Multi-physics Environment (LIME) is a software package for creating multi-physics simulation codes. Its primary application space is when computer codes are currently available to solve different parts of a multi-physics problem and now need to be coupled with other such codes. In this report we define a common domain language for discussing multi-physics coupling and describe the basic theory associated with multiphysics coupling algorithms that are to be supported in LIME. We provide an assessment of coupling techniques for both steady-state and time dependent coupled systems. Example couplings are also demonstrated.

  7. National power grid simulation capability : need and issues

    Energy Technology Data Exchange (ETDEWEB)

    Petri, Mark C. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2009-06-02

    On December 9 and 10, 2008, the Department of Homeland Security (DHS) Science and Technology Directorate sponsored a national workshop at Argonne National Laboratory to explore the need for a comprehensive modeling and simulation capability for the national electric power grid system. The workshop brought together leading electric power grid experts from federal agencies, the national laboratories, and academia to discuss the current state of power grid science and engineering and to assess if important challenges are being met. The workshop helped delineate gaps between grid needs and current capabilities and identify issues that must be addressed if a solution is to be implemented. This report is a result of the workshop and highlights power grid modeling and simulation needs, the barriers that must be overcome to address them, and the benefits of a national power grid simulation capability.

  8. Requirements Development for Interoperability Simulation Capability for Law Enforcement

    Energy Technology Data Exchange (ETDEWEB)

    Holter, Gregory M.

    2004-05-19

    The National Counterdrug Center (NCC) was initially authorized by Congress in FY 1999 appropriations to create a simulation-based counterdrug interoperability training capability. As the lead organization for Research and Analysis to support the NCC, the Pacific Northwest National Laboratory (PNNL) was responsible for developing the requirements for this interoperability simulation capability. These requirements were structured to address the hardware and software components of the system, as well as the deployment and use of the system. The original set of requirements was developed through a process of conducting a user-based survey of requirements for the simulation capability, coupled with an analysis of similar development efforts. The user-based approach ensured that existing concerns with respect to interoperability within the law enforcement community would be addressed. Law enforcement agencies within the designated pilot area of Cochise County, Arizona, were surveyed using interviews and ride-alongs during actual operations. The results of this survey were then accumulated, organized, and validated with the agencies to ensure the accuracy of the results. These requirements were then supplemented by adapting operational requirements from existing systems to ensure system reliability and operability. The NCC adopted a development approach providing incremental capability through the fielding of a phased series of progressively more capable versions of the system. This allowed for feedback from system users to be incorporated into subsequent revisions of the system requirements, and also allowed the addition of new elements as needed to adapt the system to broader geographic and geopolitical areas, including areas along the southwest and northwest U.S. borders. This paper addresses the processes used to develop and refine requirements for the NCC interoperability simulation capability, as well as the response of the law enforcement community to the use of

  9. Integrated simulation and modeling capability for alternate magnetic fusion concepts

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, B. I.; Hooper, E.B.; Jarboe, T. R.; LoDestro, L. L.; Pearlstein, L. D.; Prager, S. C.; Sarff, J. S.

    1998-11-03

    This document summarizes a strategic study addressing the development of a comprehensive modeling and simulation capability for magnetic fusion experiments with particular emphasis on devices that are alternatives to the mainline tokamak device. A code development project in this area supports two defined strategic thrust areas in the Magnetic Fusion Energy Program: (1) comprehensive simulation and modeling of magnetic fusion experiments and (2) development, operation, and modeling of magnetic fusion alternate- concept experiment

  10. Simulation modeling on the growth of firm's safety management capability

    Institute of Scientific and Technical Information of China (English)

    LIU Tie-zhong; LI Zhi-xiang

    2008-01-01

    Aiming to the deficiency of safety management measure, established simulation model about firm's safety management capability(FSMC) based on organizational learning theory. The system dynamics(SD) method was used, in which level and rate system, variable equation and system structure flow diagram was concluded. Simulation model was verified from two aspects: first, model's sensitivity to variable was tested from the gross of safety investment and the proportion of safety investment; second, variables dependency was checked up from the correlative variable of FSMC and organizational learning. The feasibility of simulation model is verified though these processes.

  11. UAS-Systems Integration, Validation, and Diagnostics Simulation Capability

    Science.gov (United States)

    Buttrill, Catherine W.; Verstynen, Harry A.

    2014-01-01

    As part of the Phase 1 efforts of NASA's UAS-in-the-NAS Project a task was initiated to explore the merits of developing a system simulation capability for UAS to address airworthiness certification requirements. The core of the capability would be a software representation of an unmanned vehicle, including all of the relevant avionics and flight control system components. The specific system elements could be replaced with hardware representations to provide Hardware-in-the-Loop (HWITL) test and evaluation capability. The UAS Systems Integration and Validation Laboratory (UAS-SIVL) was created to provide a UAS-systems integration, validation, and diagnostics hardware-in-the-loop simulation capability. This paper discusses how SIVL provides a robust and flexible simulation framework that permits the study of failure modes, effects, propagation paths, criticality, and mitigation strategies to help develop safety, reliability, and design data that can assist with the development of certification standards, means of compliance, and design best practices for civil UAS.

  12. Multiphysics simulation of ion concentration polarization induced by a surface-patterned nanoporous membrane in single channel devices.

    Science.gov (United States)

    Jia, Mingjie; Kim, Taesung

    2014-10-21

    Microfluidic devices utilize ion concentration polarization (ICP) phenomena for a variety of applications, but a comprehensive understanding of the generation of ICP is still necessary. Recently, the emergence of a novel single channel ICP (SC-ICP) device has stimulated further research on the mechanism of ICP generation, so that we developed a 2-D model of an SC-ICP device that integrates a nanoporous membrane on the bottom surface of the channel, allowing bulk flow over the membrane. We solved a set of coupled governing equations with appropriate boundary conditions to explore ICP numerically. As a result, we not only showed that the simulation results held a strong qualitative agreement with experimental results, but also found the distribution of ion concentrations in the SC-ICP device that has never been reported in previous studies. We confirmed again that the electrophoretic mobility (EPM) of counterions in the membrane is the most dominant factor determining the generation and strength of ICP, whereas the charge density of the membrane was dominant to the ICP strength only when a high EPM value was assumed. From the viewpoint of practical applications, an SC-ICP device with a long membrane under low buffer strength showed enhanced performance in the preconcentration of charged molecules. Therefore, we believe that the simulation results could not only provide sharp insight into ICP phenomena but also predict and optimize the performance of SC-ICP devices in various microfluidic applications.

  13. Environments for online maritime simulators with cloud computing capabilities

    Science.gov (United States)

    Raicu, Gabriel; Raicu, Alexandra

    2016-12-01

    This paper presents the cloud computing environments, network principles and methods for graphical development in realistic naval simulation, naval robotics and virtual interactions. The aim of this approach is to achieve a good simulation quality in large networked environments using open source solutions designed for educational purposes. Realistic rendering of maritime environments requires near real-time frameworks with enhanced computing capabilities during distance interactions. E-Navigation concepts coupled with the last achievements in virtual and augmented reality will enhance the overall experience leading to new developments and innovations. We have to deal with a multiprocessing situation using advanced technologies and distributed applications using remote ship scenario and automation of ship operations.

  14. Advances of Simulation and Expertise Capabilities in CIVA Platform

    Science.gov (United States)

    Le Ber, L.; Calmon, P.; Sollier, Th.; Mahaut, S.; Benoist, Ph.

    2006-03-01

    Simulation is more and more widely used by the different actors of industrial NDT. The French Atomic Energy Commission (CEA) launched the development of expertise software for NDT named CIVA which, at its beginning, only contained ultrasonic models from CEA laboratories. CIVA now includes Eddy current simulation tools while present work aims at facilitating integration of algorithms and models from different laboratories and to include X-ray modeling. This communication gives an overview of existing CIVA capabilities and its evolution towards an integration platform.

  15. SHARP Multiphysics Tutorials

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Y. Q. [Argonne National Lab. (ANL), Argonne, IL (United States); Shemon, E. R. [Argonne National Lab. (ANL), Argonne, IL (United States); Mahadevan, Vijay S. [Argonne National Lab. (ANL), Argonne, IL (United States); Rahaman, Ronald O. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-02-29

    SHARP, developed under the NEAMS Reactor Product Line, is an advanced modeling and simulation toolkit for the analysis of advanced nuclear reactors. SHARP is comprised of three physics modules currently including neutronics, thermal hydraulics, and structural mechanics. SHARP empowers designers to produce accurate results for modeling physical phenomena that have been identified as important for nuclear reactor analysis. SHARP can use existing physics codes and take advantage of existing infrastructure capabilities in the MOAB framework and the coupling driver/solver library, the Coupled Physics Environment (CouPE), which utilizes the widely used, scalable PETSc library. This report aims at identifying the coupled-physics simulation capability of SHARP by introducing the demonstration example called sahex in advance of the SHARP release expected by Mar 2016. sahex consists of 6 fuel pins with cladding, 1 control rod, sodium coolant and an outer duct wall that encloses all the other components. This example is carefully chosen to demonstrate the proof of concept for solving more complex demonstration examples such as EBR II assembly and ABTR full core. The workflow of preparing the input files, running the case and analyzing the results is demonstrated in this report. Moreover, an extension of the sahex model called sahex_core, which adds six homogenized neighboring assemblies to the full heterogeneous sahex model, is presented to test homogenization capabilities in both Nek5000 and PROTEUS. Some primary information on the configuration and build aspects for the SHARP toolkit, which includes capability to auto-download dependencies and configure/install with optimal flags in an architecture-aware fashion, is also covered by this report. A step-by-step instruction is provided to help users to create their cases. Details on these processes will be provided in the SHARP user manual that will accompany the first release.

  16. Multiphysics Simulation and Experimental Investigation of Aluminum Wettability on a Titanium Substrate for Laser Welding-Brazing Process

    Directory of Open Access Journals (Sweden)

    Morgan Dal

    2017-06-01

    Full Text Available The control of metal wettability is a key-factor in the field of brazing or welding-brazing. The present paper deals with the numerical simulation of the whole phenomena occurring during the assembly of dissimilar alloys. The study is realized in the frame of potential applications for the aircraft industry, considering the case of the welding-brazing of aluminum Al5754 and quasi-pure titanium Ti40. The assembly configuration, presented here, is a simplification of the real experiment. We have reduced the three-dimensional overlap configuration to a bi-dimensional case. In the present case, an aluminum cylinder is fused onto a titanium substrate. The main physical phenomena which are considered here are: the heat transfers, the fluid flows with free boundaries and the mass transfer in terms of chemical species diffusion. The numerical problem is implemented with the commercial software Comsol Multiphysics™, by coupling heat equation, Navier-Stokes and continuity equations and the free boundary motion. The latter is treated with the Arbitrary Lagrangian Eulerian method, with a particular focus on the contact angle implementation. The comparison between numerical and experimental results shows a very satisfactory agreement in terms of droplet shape, thermal field and intermetallic layer thickness. The model validates our numerical approach.

  17. Multiphysics Simulations of Entrained Flow Gasification. Part I: Validating the Nonreacting Flow Solver and the Particle Turbulent Dispersion Model

    KAUST Repository

    Kumar, Mayank

    2012-01-19

    In this two-part paper, we describe the construction, validation, and application of a multiscale model of entrained flow gasification. The accuracy of the model is demonstrated by (1) rigorously constructing and validating the key constituent submodels against relevant canonical test cases from the literature and (2) validating the integrated model against experimental data from laboratory scale and commercial scale gasifiers. In part I, the flow solver and particle turbulent dispersion models are validated against experimental data from nonswirling flow and swirling flow test cases in an axisymmetric sudden expansion geometry and a two-phase flow test case in a cylindrical bluff body geometry. Results show that while the large eddy simulation (LES) performs best among all tested models in predicting both swirling and nonswirling flows, the shear stress transport (SST) k-ω model is the best choice among the commonly used Reynolds-averaged Navier-Stokes (RANS) models. The particle turbulent dispersion model is accurate enough in predicting particle trajectories in complex turbulent flows when the underlying turbulent flow is well predicted. Moreover, a commonly used modeling constant in the particle dispersion model is optimized on the basis of comparisons with particle-phase experimental data for the two-phase flow bluff body case. © 2011 American Chemical Society.

  18. A multiphysics/multiscale 2D numerical simulation of scaffold-based cartilage regeneration under interstitial perfusion in a bioreactor.

    Science.gov (United States)

    Sacco, Riccardo; Causin, Paola; Zunino, Paolo; Raimondi, Manuela T

    2011-07-01

    In vitro tissue engineering is investigated as a potential source of functional tissue constructs for cartilage repair, as well as a model system for controlled studies of cartilage development and function. Among the different kinds of devices for the cultivation of 3D cartilage cell colonies, we consider here polymeric scaffold-based perfusion bioreactors, where an interstitial fluid supplies nutrients and oxygen to the growing biomass. At the same time, the fluid-induced shear acts as a physiologically relevant stimulus for the metabolic activity of cells, provided that the shear stress level is appropriately tuned. In this complex environment, mathematical and computational modeling can help in the optimal design of the bioreactor configuration. In this perspective, we propose a computational model for the simulation of the biomass growth, under given inlet and geometrical conditions, where nutrient concentration, fluid dynamic field and cell growth are consistently coupled. The biomass growth model is calibrated with respect to the shear stress dependence on experimental data using a simplified short-time analysis in which the nutrient concentration and the fluid-induced shear stress are assumed constant in time and uniform in space. Volume averaging techniques are used to derive effective parameters that allow to upscale the microscopic structural properties to the macroscopic level. The biomass growth predictions obtained in this way are significant for long times of culture.

  19. 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

  20. Modular ORIGEN-S for multi-physics code systems

    Energy Technology Data Exchange (ETDEWEB)

    Yesilyurt, Gokhan; Clarno, Kevin T.; Gauld, Ian C., E-mail: yesilyurtg@ornl.gov, E-mail: clarnokt@ornl.gov, E-mail: gauldi@ornl.gov [Oak Ridge National Laboratory, TN (United States); Galloway, Jack, E-mail: jack@galloways.net [Los Alamos National Laboratory, Los Alamos, NM (United States)

    2011-07-01

    The ORIGEN-S code in the SCALE 6.0 nuclear analysis code suite is a well-validated tool to calculate the time-dependent concentrations of nuclides due to isotopic depletion, decay, and transmutation for many systems in a wide range of time scales. Application areas include nuclear reactor and spent fuel storage analyses, burnup credit evaluations, decay heat calculations, and environmental assessments. Although simple to use within the SCALE 6.0 code system, especially with the ORIGEN-ARP graphical user interface, it is generally complex to use as a component within an externally developed code suite because of its tight coupling within the infrastructure of the larger SCALE 6.0 system. The ORIGEN2 code, which has been widely integrated within other simulation suites, is no longer maintained by Oak Ridge National Laboratory (ORNL), has obsolete data, and has a relatively small validation database. Therefore, a modular version of the SCALE/ORIGEN-S code was developed to simplify its integration with other software packages to allow multi-physics nuclear code systems to easily incorporate the well-validated isotopic depletion, decay, and transmutation capability to perform realistic nuclear reactor and fuel simulations. SCALE/ORIGEN-S was extensively restructured to develop a modular version that allows direct access to the matrix solvers embedded in the code. Problem initialization and the solver were segregated to provide a simple application program interface and fewer input/output operations for the multi-physics nuclear code systems. Furthermore, new interfaces were implemented to access and modify the ORIGEN-S input variables and nuclear cross-section data through external drivers. Three example drivers were implemented, in the C, C++, and Fortran 90 programming languages, to demonstrate the modular use of the new capability. This modular version of SCALE/ORIGEN-S has been embedded within several multi-physics software development projects at ORNL, including

  1. Advanced SAR simulator with multi-beam interferometric capabilities

    Science.gov (United States)

    Reppucci, Antonio; Márquez, José; Cazcarra, Victor; Ruffini, Giulio

    2014-10-01

    State of the art simulations are of great interest when designing a new instrument, studying the imaging mechanisms due to a given scenario or for inversion algorithm design as they allow to analyze and understand the effects of different instrument configurations and targets compositions. In the framework of the studies about a new instruments devoted to the estimation of the ocean surface movements using Synthetic Aperture Radar along-track interferometry (SAR-ATI) an End-to-End simulator has been developed. The simulator, built in a high modular way to allow easy integration of different processing-features, deals with all the basic operations involved in an end to end scenario. This includes the computation of the position and velocity of the platform (airborne/spaceborne) and the geometric parameters defining the SAR scene, the surface definition, the backscattering computation, the atmospheric attenuation, the instrument configuration, and the simulation of the transmission/reception chains and the raw data. In addition, the simulator provides a inSAR processing suit and a sea surface movement retrieval module. Up to four beams (each one composed by a monostatic and a bistatic channel) can be activated. Each channel provides raw data and SLC images with the possibility of choosing between Strip-map and Scansar modes. Moreover, the software offers the possibility of radiometric sensitivity analysis and error analysis due atmospheric disturbances, instrument-noise, interferogram phase-noise, platform velocity and attitude variations. In this paper, the architecture and the capabilities of this simulator will be presented. Meaningful simulation examples will be shown.

  2. Multi-physic simulations of irradiation experiments in a technological irradiation reactor; Modelisation pluridisciplinaire d'experiences d'irradiation dans un reacteur d'irradiation technologique

    Energy Technology Data Exchange (ETDEWEB)

    Bonaccorsi, Th

    2007-09-15

    A Material Testing Reactor (MTR) makes it possible to irradiate material samples under intense neutron and photonic fluxes. These experiments are carried out in experimental devices localised in the reactor core or in periphery (reflector). Available physics simulation tools only treat, most of the time, one physics field in a very precise way. Multi-physic simulations of irradiation experiments therefore require a sequential use of several calculation codes and data exchanges between these codes: this corresponds to problems coupling. In order to facilitate multi-physic simulations, this thesis sets up a data model based on data-processing objects, called Technological Entities. This data model is common to all of the physics fields. It permits defining the geometry of an irradiation device in a parametric way and to associate information about materials to it. Numerical simulations are encapsulated into interfaces providing the ability to call specific functionalities with the same command (to initialize data, to launch calculations, to post-treat, to get results,... ). Thus, once encapsulated, numerical simulations can be re-used for various studies. This data model is developed in a SALOME platform component. The first application case made it possible to perform neutronic simulations (OSIRIS reactor and RJH) coupled with fuel behavior simulations. In a next step, thermal hydraulics could also be taken into account. In addition to the improvement of the calculation accuracy due to the physical phenomena coupling, the time spent in the development phase of the simulation is largely reduced and the possibilities of uncertainty treatment are under consideration. (author)

  3. MASSIVE HYBRID PARALLELISM FOR FULLY IMPLICIT MULTIPHYSICS

    Energy Technology Data Exchange (ETDEWEB)

    Cody J. Permann; David Andrs; John W. Peterson; Derek R. Gaston

    2013-05-01

    As hardware advances continue to modify the supercomputing landscape, traditional scientific software development practices will become more outdated, ineffective, and inefficient. The process of rewriting/retooling existing software for new architectures is a Sisyphean task, and results in substantial hours of development time, effort, and money. Software libraries which provide an abstraction of the resources provided by such architectures are therefore essential if the computational engineering and science communities are to continue to flourish in this modern computing environment. The Multiphysics Object Oriented Simulation Environment (MOOSE) framework enables complex multiphysics analysis tools to be built rapidly by scientists, engineers, and domain specialists, while also allowing them to both take advantage of current HPC architectures, and efficiently prepare for future supercomputer designs. MOOSE employs a hybrid shared-memory and distributed-memory parallel model and provides a complete and consistent interface for creating multiphysics analysis tools. In this paper, a brief discussion of the mathematical algorithms underlying the framework and the internal object-oriented hybrid parallel design are given. Representative massively parallel results from several applications areas are presented, and a brief discussion of future areas of research for the framework are provided.

  4. Predictive Capability Maturity Model for computational modeling and simulation.

    Energy Technology Data Exchange (ETDEWEB)

    Oberkampf, William Louis; Trucano, Timothy Guy; Pilch, Martin M.

    2007-10-01

    The Predictive Capability Maturity Model (PCMM) is a new model that can be used to assess the level of maturity of computational modeling and simulation (M&S) efforts. The development of the model is based on both the authors experience and their analysis of similar investigations in the past. The perspective taken in this report is one of judging the usefulness of a predictive capability that relies on the numerical solution to partial differential equations to better inform and improve decision making. The review of past investigations, such as the Software Engineering Institute's Capability Maturity Model Integration and the National Aeronautics and Space Administration and Department of Defense Technology Readiness Levels, indicates that a more restricted, more interpretable method is needed to assess the maturity of an M&S effort. The PCMM addresses six contributing elements to M&S: (1) representation and geometric fidelity, (2) physics and material model fidelity, (3) code verification, (4) solution verification, (5) model validation, and (6) uncertainty quantification and sensitivity analysis. For each of these elements, attributes are identified that characterize four increasing levels of maturity. Importantly, the PCMM is a structured method for assessing the maturity of an M&S effort that is directed toward an engineering application of interest. The PCMM does not assess whether the M&S effort, the accuracy of the predictions, or the performance of the engineering system satisfies or does not satisfy specified application requirements.

  5. New simulation capability for gamma ray mirror experiments

    Energy Technology Data Exchange (ETDEWEB)

    Descalle, Marie-Anne [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ruz-Armendariz, Jaime [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Decker, Todd [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brejhnolt, Nicolai [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Pivovaroff, Michael [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-09-28

    This report provides a description of the simulation toolkit developed at Lawrence Livermore National Laboratory to support the design of nuclear safeguards experiments using grazing incidence multilayer mirrors in the energy band of uranium (U) and plutonium (Pu) emission lines. This effort was motivated by the data analysis of a scoping experiment at the Irradiated Fuels Examination Facility (IFEL) at Oak Ridge National Laboratory in FY13 and of a benchmark experiment at the Idaho National Laboratory (INL) in FY14 that highlighted the need for predictive tools built around a ray-tracing capability. This report presents the simulation toolkit and relevant results such as the simulated spectra for TMI, MOX, and ATM106 fuel rods based on spent fuel models provided by Los Alamos National Laboratory and for a virgin high 240Pu-content fuel plate, as well as models of the IFEL and INL experiments implemented in the ray tracing tool. The beam position and height were validated against the INL ~60 keV americium data. Examples of alternate configurations of the optics or experimental set-up illustrate the future use of the simulation suite to guide the next IFEL experimental campaign.

  6. Time-parallel multiscale/multiphysics framework

    Energy Technology Data Exchange (ETDEWEB)

    Frantziskonis, G. [University of Arizona; Muralidharan, Krishna [University of Arizona; Deymier, Pierre [University of Arizona; Simunovic, Srdjan [ORNL; Nukala, Phani K [ORNL; Pannala, Sreekanth [ORNL

    2009-01-01

    We introduce the time-parallel compound wavelet matrix method (tpCWM) for modeling the temporal evolution of multiscale and multiphysics systems. The method couples time parallel (TP) and CWM methods operating at different spatial and temporal scales. We demonstrate the efficiency of our approach on two examples: a chemical reaction kinetic system and a non-linear predator prey system. Our results indicate that the tpCWM technique is capable of accelerating time-to-solution by 2 3-orders of magnitude and is amenable to efficient parallel implementation.

  7. Satellite Docking Simulator with Generic Contact Dynamics Capabilities

    Science.gov (United States)

    Ma, O.; Crabtree, D.; Carr, R.; Gonthier, Y.; Martin, E.; Piedboeuf, J.-C.

    2002-01-01

    satellite servicing. Simulations are also instrumental in concept studies during proposals and early development stages. Finally, simulations are useful during the operational phase of satellite servicing: improving the operational procedures; training ground operators; command and control, etc. Hence the need exists for a Satellite Servicing Simulator, which will support a project throughout its lifecycle. The paper addresses a project to develop a Simulink-based Satellite Docking Simulator (SDS) with generic Contact Dynamics (CD) capabilities. The simulator is intended to meet immediate practical demands for development of complex docking systems and operations at MD Robotics. The docking phase is the most critical and complex phase of the entire servicing sequence, and without docking there is no servicing. Docking mechanisms are often quite complex, especially when built to dock with a satellite manufactured without special docking interfaces. For successful docking operations, the design of a docking system must take into consideration: complexity of 3D geometric shapes defining the contact interfaces; sophistication of the docking mechanism; friction and stiction at the contacting surfaces; compliance (stiffness) and damping, in all axes; positional (translation and rotation) misalignments and relative velocities, in all axes; inertial properties of the docking satellites (including their distribution); complexity of the drive mechanisms and control sub-systems for the overall docking system; fully autonomous or tele-operated docking from the ground; etc. The docking simulator, which makes use of the proven Contact Dynamics Toolkit (CDT) developed by MD Robotics, is thus practically indispensable for the docking system designer. The use of the simulator could greatly reduce the prototyping and development time of a docking interface. A special feature of the simulator, which required an update of CDT, is variable step-size integration. This new capability permits

  8. Coarse-grained DNA model capable of simulating ribose flexibility

    CERN Document Server

    Kovaleva, Natalya A; Mazo, Mikhail A; Zubova, Elena A

    2014-01-01

    We propose a "sugar" coarse-grained (CG) DNA model capable of simulating both biologically significant B- and A-DNA forms. The number of degrees of freedom is reduced to six grains per nucleotide. We show that this is the minimal number sufficient for this purpose. The key features of the sugar CG DNA model are: (1) simulation of sugar repuckering between C2'-endo and C3'-endo by the use of one non-harmonic potential and one three-particle potential, (2) explicit representation of sodium counterions and (3) implicit solvent approach. Effects of solvation and of partial charge screening at small distances are taken into account through the shape of potentials of interactions between charged particles. We obtain parameters of the sugar CG DNA model from the all-atom AMBER model. The suggested model allows adequate simulation of the transitions between A- and B-DNA forms, as well as of large deformations of long DNA molecules, for example, in binding with proteins. Small modifications of the model can provide th...

  9. An Integrated Software Package to Enable Predictive Simulation Capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yousu; Fitzhenry, Erin B.; Jin, Shuangshuang; Palmer, Bruce J.; Sharma, Poorva; Huang, Zhenyu

    2016-08-11

    The power grid is increasing in complexity due to the deployment of smart grid technologies. Such technologies vastly increase the size and complexity of power grid systems for simulation and modeling. This increasing complexity necessitates not only the use of high-performance-computing (HPC) techniques, but a smooth, well-integrated interplay between HPC applications. This paper presents a new integrated software package that integrates HPC applications and a web-based visualization tool based on a middleware framework. This framework can support the data communication between different applications. Case studies with a large power system demonstrate the predictive capability brought by the integrated software package, as well as the better situational awareness provided by the web-based visualization tool in a live mode. Test results validate the effectiveness and usability of the integrated software package.

  10. Radar micro-Doppler simulations of classification capability with frequency

    Science.gov (United States)

    Tahmoush, David; Silvious, Jerry

    2012-06-01

    Classifying human signatures using radar requires a detailed understanding of the RF scattering phenomenology associated with humans as well as their motion. We model humans engaged in the activity of walking and analyze the separability of different body parts with frequency as well as lookdown angle. This work seeks to estimate the ability to classify the micro-Doppler signals generated by human motion, and especially arm motion, as a function of the radar frequency and other parameters. The simulations imply that for classification using arm motion, frequencies at Ku-band or higher are probably required, and that lookdown angle has a significant effect on the classification capability of the radar. Additionally, the sensitivity of the system required to isolate the motion of different body parts is estimated.

  11. PYRO: New capability for isotopic mass tracking in pyroprocess simulation

    Energy Technology Data Exchange (ETDEWEB)

    Liaw, J.R.; Ackerman, J.P.

    1990-01-01

    A new computational code package called PYRO has been developed to support the IFR fuel recycle demonstration project in the HFEF/S facility at ANL-W. The basic pyrochemical code PYRO1-1 models the atomic mass flows and phase compositions of 48 essential chemical elements involved in the pyroprocess. It has been extended to PYRO1-2 by linking with the ORIGEN code to track more than 1000 isotopic species, their radioactive decays, and related phenomena. This paper first describes the pyroprocess to be modeled and the pyrochemical capability that has been implemented in PYRO1-1, and then gives a full account on the algorithm of extending it to PYRO1-2 for isotopic mass tracking. Results from several scoping and simulation runs will be discussed to illustrate the significance of modeling in-process radioactive decays. 16 refs., 8 figs., 2 tabs.

  12. Science based integrated approach to advanced nuclear fuel development - integrated multi-scale multi-physics hierarchical modeling and simulation framework Part III: cladding

    Energy Technology Data Exchange (ETDEWEB)

    Tome, Carlos N [Los Alamos National Laboratory; Caro, J A [Los Alamos National Laboratory; Lebensohn, R A [Los Alamos National Laboratory; Unal, Cetin [Los Alamos National Laboratory; Arsenlis, A [LLNL; Marian, J [LLNL; Pasamehmetoglu, K [INL

    2010-01-01

    Advancing the performance of Light Water Reactors, Advanced Nuclear Fuel Cycles, and Advanced Reactors, such as the Next Generation Nuclear Power Plants, requires enhancing our fundamental understanding of fuel and materials behavior under irradiation. The capability to accurately model the nuclear fuel systems to develop predictive tools is critical. Not only are fabrication and performance models needed to understand specific aspects of the nuclear fuel, fully coupled fuel simulation codes are required to achieve licensing of specific nuclear fuel designs for operation. The backbone of these codes, models, and simulations is a fundamental understanding and predictive capability for simulating the phase and microstructural behavior of the nuclear fuel system materials and matrices. In this paper we review the current status of the advanced modeling and simulation of nuclear reactor cladding, with emphasis on what is available and what is to be developed in each scale of the project, how we propose to pass information from one scale to the next, and what experimental information is required for benchmarking and advancing the modeling at each scale level.

  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. Extreme Environment Simulation - Current and New Capabilities to Simulate Venus and Other Planetary Bodies

    Science.gov (United States)

    Kremic, Tibor; Vento, Dan; Lalli, Nick; Palinski, Timothy

    2014-01-01

    Science, technology, and planetary mission communities have a growing interest in components and systems that are capable of working in extreme (high) temperature and pressure conditions. Terrestrial applications range from scientific research, aerospace, defense, automotive systems, energy storage and power distribution, deep mining and others. As the target environments get increasingly extreme, capabilities to develop and test the sensors and systems designed to operate in such environments will be required. An application of particular importance to the planetary science community is the ability for a robotic lander to survive on the Venus surface where pressures are nearly 100 times that of Earth and temperatures approach 500C. The scientific importance and relevance of Venus missions are stated in the current Planetary Decadal Survey. Further, several missions to Venus were proposed in the most recent Discovery call. Despite this interest, the ability to accurately simulate Venus conditions at a scale that can test and validate instruments and spacecraft systems and accurately simulate the Venus atmosphere has been lacking. This paper discusses and compares the capabilities that are known to exist within and outside the United States to simulate the extreme environmental conditions found in terrestrial or planetary surfaces including the Venus atmosphere and surface. The paper then focuses on discussing the recent additional capability found in the NASA Glenn Extreme Environment Rig (GEER). The GEER, located at the NASA Glenn Research Center in Cleveland, Ohio, is designed to simulate not only the temperature and pressure extremes described, but can also accurately reproduce the atmospheric compositions of bodies in the solar system including those with acidic and hazardous elements. GEER capabilities and characteristics are described along with operational considerations relevant to potential users. The paper presents initial operating results and concludes

  15. Multiphysics modeling and uncertainty quantification for an active composite reflector

    Science.gov (United States)

    Peterson, Lee D.; Bradford, S. C.; Schiermeier, John E.; Agnes, Gregory S.; Basinger, Scott A.

    2013-09-01

    A multiphysics, high resolution simulation of an actively controlled, composite reflector panel is developed to extrapolate from ground test results to flight performance. The subject test article has previously demonstrated sub-micron corrected shape in a controlled laboratory thermal load. This paper develops a model of the on-orbit performance of the panel under realistic thermal loads, with an active heater control system, and performs an uncertainty quantification of the predicted response. The primary contribution of this paper is the first reported application of the Sandia developed Sierra mechanics simulation tools to a spacecraft multiphysics simulation of a closed-loop system, including uncertainty quantification. The simulation was developed so as to have sufficient resolution to capture the residual panel shape error that remains after the thermal and mechanical control loops are closed. An uncertainty quantification analysis was performed to assess the predicted tolerance in the closed-loop wavefront error. Key tools used for the uncertainty quantification are also described.

  16. Enhancing Learning Capabilities by Providing Transparency in Business Simulators.

    Science.gov (United States)

    Groessler, Andreas; Maier, Frank H.; Milling, Peter M.

    2000-01-01

    Discussion of computer-based simulations for business focuses on adding transparency through system dynamics techniques. Describes an experiment that evaluated the relevance and the effects of providing structural transparency to users of business simulators and suggests further research. (Contains 51 references.) (LRW)

  17. Scalable Adaptive Multilevel Solvers for Multiphysics Problems

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jinchao

    2014-12-01

    In this project, we investigated adaptive, parallel, and multilevel methods for numerical modeling of various real-world applications, including Magnetohydrodynamics (MHD), complex fluids, Electromagnetism, Navier-Stokes equations, and reservoir simulation. First, we have designed improved mathematical models and numerical discretizaitons for viscoelastic fluids and MHD. Second, we have derived new a posteriori error estimators and extended the applicability of adaptivity to various problems. Third, we have developed multilevel solvers for solving scalar partial differential equations (PDEs) as well as coupled systems of PDEs, especially on unstructured grids. Moreover, we have integrated the study between adaptive method and multilevel methods, and made significant efforts and advances in adaptive multilevel methods of the multi-physics problems.

  18. Water Hammer Simulations of MMH Propellant - New Capability Demonstration of the Generalized Fluid Flow Simulation Program

    Science.gov (United States)

    Burkhardt, Z.; Ramachandran, N.; Majumdar, A.

    2017-01-01

    Fluid Transient analysis is important for the design of spacecraft propulsion system to ensure structural stability of the system in the event of sudden closing or opening of the valve. Generalized Fluid System Simulation Program (GFSSP), a general purpose flow network code developed at NASA/MSFC is capable of simulating pressure surge due to sudden opening or closing of valve when thermodynamic properties of real fluid are available for the entire range of simulation. Specifically GFSSP needs an accurate representation of pressure-density relationship in order to predict pressure surge during a fluid transient. Unfortunately, the available thermodynamic property programs such as REFPROP, GASP or GASPAK does not provide the thermodynamic properties of Monomethylhydrazine (MMH). This paper will illustrate the process used for building a customized table of properties of state variables from available properties and speed of sound that is required by GFSSP for simulation. Good agreement was found between the simulations and measured data. This method can be adopted for modeling flow networks and systems with other fluids whose properties are not known in detail in order to obtain general technical insight. Rigorous code validation of this approach will be done and reported at a future date.

  19. Development of predictive simulation capability for reactive multiphase flow

    Energy Technology Data Exchange (ETDEWEB)

    VanderHeyden, W.B.; Kendrick, B.K.

    1998-12-31

    This is the final report of a Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of the project was to develop a self-sustained research program for advanced computer simulation of industrial reactive multiphase flows. The prototype research problem was a three-phase alumina precipitator used in the Bayer process, a key step in aluminum refining. Accomplishments included the development of an improved reaction mechanism of the alumina precipitation growth process, the development of an efficient methods for handling particle size distribution in multiphase flow simulation codes, the incorporation of precipitation growth and agglomeration kinetics in LANL's CFDLIB multiphase flow code library and the evaluation of multiphase turbulence closure models for bubbly flow simulations.

  20. Stabilized FE simulation of prototype thermal-hydraulics problems with integrated adjoint-based capabilities

    Science.gov (United States)

    Shadid, J. N.; Smith, T. M.; Cyr, E. C.; Wildey, T. M.; Pawlowski, R. P.

    2016-09-01

    A critical aspect of applying modern computational solution methods to complex multiphysics systems of relevance to nuclear reactor modeling, is the assessment of the predictive capability of specific proposed mathematical models. In this respect the understanding of numerical error, the sensitivity of the solution to parameters associated with input data, boundary condition uncertainty, and mathematical models is critical. Additionally, the ability to evaluate and or approximate the model efficiently, to allow development of a reasonable level of statistical diagnostics of the mathematical model and the physical system, is of central importance. In this study we report on initial efforts to apply integrated adjoint-based computational analysis and automatic differentiation tools to begin to address these issues. The study is carried out in the context of a Reynolds averaged Navier-Stokes approximation to turbulent fluid flow and heat transfer using a particular spatial discretization based on implicit fully-coupled stabilized FE methods. Initial results are presented that show the promise of these computational techniques in the context of nuclear reactor relevant prototype thermal-hydraulics problems.

  1. Finite Element Modeling, Simulation, Tools, and Capabilities at Superform

    Science.gov (United States)

    Raman, Hari; Barnes, A. J.

    2010-06-01

    Over the past thirty years Superform has been a pioneer in the SPF arena, having developed a keen understanding of the process and a range of unique forming techniques to meet varying market needs. Superform’s high-profile list of customers includes Boeing, Airbus, Aston Martin, Ford, and Rolls Royce. One of the more recent additions to Superform’s technical know-how is finite element modeling and simulation. Finite element modeling is a powerful numerical technique which when applied to SPF provides a host of benefits including accurate prediction of strain levels in a part, presence of wrinkles and predicting pressure cycles optimized for time and part thickness. This paper outlines a brief history of finite element modeling applied to SPF and then reviews some of the modeling tools and techniques that Superform have applied and continue to do so to successfully superplastically form complex-shaped parts. The advantages of employing modeling at the design stage are discussed and illustrated with real-world examples.

  2. Thermo-mechanical analysis using a multiphysics approach

    Energy Technology Data Exchange (ETDEWEB)

    Delprete, C; Rosso, C [Dipartimento di Meccanica, Politecnico di Torino, Corso Duca degli Abruzzi, 24, Torino (Italy); Freschi, F; Repetto, M, E-mail: cristiana.delprete@polito.i [Dipartimento di Ingegneria Elettrica, Politecnico di Torino, Corso Duca degli Abruzzi, 24, Torino (Italy)

    2009-08-01

    In the paper the Cell Method, a discrete method for solving partial differential equations, is applied to a time dependent thermo-mechanical problem. The basic equations are developed with a multiphysics approach and results, both in two-dimensional and tree-dimensional models, are presented. By means of the comparison with finite element approach, some advantages of the proposed methodology are highlighted, in particular quick model construction, capability to separate thermal strain from the mechanical one and, as a consequence, the capability to model the strain and stress evolution in a time dependent problem, considering possible mutual effects between thermal and mechanical fields.

  3. Multiphysics Integrated Coupling Environment (MICE) User Manual

    Energy Technology Data Exchange (ETDEWEB)

    Varija Agarwal; Donna Post Guillen

    2013-08-01

    The complex, multi-part nature of waste glass melters used in nuclear waste vitrification poses significant modeling challenges. The focus of this project has been to couple a 1D MATLAB model of the cold cap region within a melter with a 3D STAR-CCM+ model of the melter itself. The Multiphysics Integrated Coupling Environment (MICE) has been developed to create a cohesive simulation of a waste glass melter that accurately represents the cold cap. The one-dimensional mathematical model of the cold cap uses material properties, axial heat, and mass fluxes to obtain a temperature profile for the cold cap, the region where feed-to-glass conversion occurs. The results from Matlab are used to update simulation data in the three-dimensional STAR-CCM+ model so that the cold cap is appropriately incorporated into the 3D simulation. The two processes are linked through ModelCenter integration software using time steps that are specified for each process. Data is to be exchanged circularly between the two models, as the inputs and outputs of each model depend on the other.

  4. A multiphysics and multiscale software environment for modeling astrophysical systems

    CERN Document Server

    Zwart, Simon Portegies; Harfst, Stefan; Groen, Derek; Fujii, Michiko

    2008-01-01

    We present MUSE, a software framework for combining existing computational tools for different astrophysical domains into a single multiphysics, multiscale application. MUSE facilitates the coupling of existing codes written in different languages by providing inter-language tools and by specifying an interface between each module and the framework that represents a balance between generality and computational efficiency. This approach allows scientists to use combinations of codes to solve highly-coupled problems without the need to write new codes for other domains or significantly alter their existing codes. MUSE currently incorporates the domains of stellar dynamics, stellar evolution and stellar hydrodynamics for studying generalized stellar systems. We have now reached a ``Noah's Ark'' milestone, with (at least) two available numerical solvers for each domain. MUSE can treat multi-scale and multi-physics systems in which the time- and size-scales are well separated, like simulating the evolution of plan...

  5. COLLABORATIVE DESIGN OF MULTIPHYSICS PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    SONG Shaoyun; LI Shiqi

    2007-01-01

    Collaborative design is recommendedto solve multiphysics problems (MPPS). Firstly,mathematical model of MPPS is constructed and solved by a proposed partitioned method, analysis of which suggests that collaborative design be feasible to solve MPPS. As the key technology of collaborative design of MPPS, a task collaboration algorithm is then proposed. To develop the application framework of collaborative design, applied unified process(AUP) is proposed based on rational unified process(RUP). Then AUP is used to develop the collaborative design platform, whose function framework is constructed according to the process of project management. Finally three MPPS are solved on this platform and the results suggest that the proposed model, algorithm and framework be feasible.

  6. Interface COMSOL-PHREEQC (iCP), an efficient numerical framework for the solution of coupled multiphysics and geochemistry

    Science.gov (United States)

    Nardi, Albert; Idiart, Andrés; Trinchero, Paolo; de Vries, Luis Manuel; Molinero, Jorge

    2014-08-01

    This paper presents the development, verification and application of an efficient interface, denoted as iCP, which couples two standalone simulation programs: the general purpose Finite Element framework COMSOL Multiphysics® and the geochemical simulator PHREEQC. The main goal of the interface is to maximize the synergies between the aforementioned codes, providing a numerical platform that can efficiently simulate a wide number of multiphysics problems coupled with geochemistry. iCP is written in Java and uses the IPhreeqc C++ dynamic library and the COMSOL Java-API. Given the large computational requirements of the aforementioned coupled models, special emphasis has been placed on numerical robustness and efficiency. To this end, the geochemical reactions are solved in parallel by balancing the computational load over multiple threads. First, a benchmark exercise is used to test the reliability of iCP regarding flow and reactive transport. Then, a large scale thermo-hydro-chemical (THC) problem is solved to show the code capabilities. The results of the verification exercise are successfully compared with those obtained using PHREEQC and the application case demonstrates the scalability of a large scale model, at least up to 32 threads.

  7. Resolved-particle simulation by the Physalis method: Enhancements and new capabilities

    NARCIS (Netherlands)

    Sierakowski, A.; Prosperetti, A.

    2016-01-01

    We present enhancements and new capabilities of the Physalis method for simulating disperse multiphase flows using particle-resolved simulation. The current work enhances the previous method by incorporating a new type of pressure-Poisson solver that couples with a new Physalis particle pressure bou

  8. Towards an efficient multiphysics model for nuclear reactor dynamics

    Directory of Open Access Journals (Sweden)

    Obaidurrahman K.

    2015-01-01

    Full Text Available Availability of fast computer resources nowadays has facilitated more in-depth modeling of complex engineering systems which involve strong multiphysics interactions. This multiphysics modeling is an important necessity in nuclear reactor safety studies where efforts are being made worldwide to combine the knowledge from all associated disciplines at one place to accomplish the most realistic simulation of involved phenomenon. On these lines coupled modeling of nuclear reactor neutron kinetics, fuel heat transfer and coolant transport is a regular practice nowadays for transient analysis of reactor core. However optimization between modeling accuracy and computational economy has always been a challenging task to ensure the adequate degree of reliability in such extensive numerical exercises. Complex reactor core modeling involves estimation of evolving 3-D core thermal state, which in turn demands an expensive multichannel based detailed core thermal hydraulics model. A novel approach of power weighted coupling between core neutronics and thermal hydraulics presented in this work aims to reduce the bulk of core thermal calculations in core dynamics modeling to a significant extent without compromising accuracy of computation. Coupled core model has been validated against a series of international benchmarks. Accuracy and computational efficiency of the proposed multiphysics model has been demonstrated by analyzing a reactivity initiated transient.

  9. Final report on LDRD project : coupling strategies for multi-physics applications.

    Energy Technology Data Exchange (ETDEWEB)

    Hopkins, Matthew Morgan; Moffat, Harry K.; Carnes, Brian; Hooper, Russell Warren; Pawlowski, Roger P.

    2007-11-01

    Many current and future modeling applications at Sandia including ASC milestones will critically depend on the simultaneous solution of vastly different physical phenomena. Issues due to code coupling are often not addressed, understood, or even recognized. The objectives of the LDRD has been both in theory and in code development. We will show that we have provided a fundamental analysis of coupling, i.e., when strong coupling vs. a successive substitution strategy is needed. We have enabled the implementation of tighter coupling strategies through additions to the NOX and Sierra code suites to make coupling strategies available now. We have leveraged existing functionality to do this. Specifically, we have built into NOX the capability to handle fully coupled simulations from multiple codes, and we have also built into NOX the capability to handle Jacobi Free Newton Krylov simulations that link multiple applications. We show how this capability may be accessed from within the Sierra Framework as well as from outside of Sierra. The critical impact from this LDRD is that we have shown how and have delivered strategies for enabling strong Newton-based coupling while respecting the modularity of existing codes. This will facilitate the use of these codes in a coupled manner to solve multi-physic applications.

  10. 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

  11. Desert Rats 2011 Mission Simulation: Effects of Microgravity Operational Modes on Fields Geology Capabilities

    Science.gov (United States)

    Bleacher, Jacob E.; Hurtado, J. M., Jr.; Meyer, J. A.

    2012-01-01

    Desert Research and Technology Studies (DRATS) is a multi-year series of NASA tests that deploy planetary surface hardware and exercise mission and science operations in difficult conditions to advance human and robotic exploration capabilities. DRATS 2011 (Aug. 30-Sept. 9, 2011) tested strategies for human exploration of microgravity targets such as near-Earth asteroids (NEAs). Here we report the crew perspective on the impact of simulated microgravity operations on our capability to conduct field geology.

  12. Development of dynamic simulation of TF34-GE-100 turbofan engine with post-stall capability

    Science.gov (United States)

    Krosel, S. M.

    1984-01-01

    This paper describes the development of a hybrid computer simulation of a TF34-GE-100 turbofan engine with post-stall capability. The simulation operates in real-time and will be used to test and evaluate stall recovery control modes for this engine. The simulation calculations are performed by an analog computer with a peripheral multivariable function generation unit used for computing bivariate functions. Tabular listings of simulation variables are obtained by interfacing to a digital computer and using a custom software package for data collection and display.

  13. Dispersion analysis and linear error analysis capabilities of the space vehicle dynamics simulation program

    Science.gov (United States)

    Snow, L. S.; Kuhn, A. E.

    1975-01-01

    Previous error analyses conducted by the Guidance and Dynamics Branch of NASA have used the Guidance Analysis Program (GAP) as the trajectory simulation tool. Plans are made to conduct all future error analyses using the Space Vehicle Dynamics Simulation (SVDS) program. A study was conducted to compare the inertial measurement unit (IMU) error simulations of the two programs. Results of the GAP/SVDS comparison are presented and problem areas encountered while attempting to simulate IMU errors, vehicle performance uncertainties and environmental uncertainties using SVDS are defined. An evaluation of the SVDS linear error analysis capability is also included.

  14. Multi-physics modeling of large ring motor for mining industry - Combining electromagnetism, fluid mechanics, mass and heat transfer in engineering design

    DEFF Research Database (Denmark)

    Andersen, Søren Bøgh; Santos, Ilmar F.; Fuerst, Axel

    2015-01-01

    electromagnet, thermal and structural interactions. This multi-physics model will later on be used for simulating and parameter optimization of a gearless mill drive. What has been proposed is a multi-physics model where the core losses are determined through a series of static finite element magnetic...

  15. Capabilities of Numerical Simulation of Multiphase Flows in Centrifugal Pumps using Modern CFD Software

    CERN Document Server

    Kochevsky, A N

    2005-01-01

    The paper describes capabilities of numerical simulation of liquid flows with solid and/or gas admixtures in centrifugal pumps using modern commercial CFD software packages, with the purpose to predict performance curves of the pumps treating such media. In particular, the approaches and multiphase flow models available in the package CFX-5 are described; their advantages and disadvantages are analyzed.

  16. Documentation of GEMASS entry to touchdown simulation. [space shuttle orbiter capability

    Science.gov (United States)

    Waibel, R. H.

    1977-01-01

    The entry-to-touchdown space shuttle orbiter simulation capability incorporated into the GEMASS subprogram 33 (3-DOF) is documented. A digital autopilot interfaces between GEMASS and the guidance. Vehicle attitude is determined by use of the ability of GEMASS to integrate differential equations in addition to the equations of motion. Vehicle aerodynamic characteristics are obtained from an aerodynamic data tape and control surface deflections required to trim the vehicle, and trimmed aerodynamic coefficients are determined internally. Several indicators to allow evaluation of subsystem performance are included; as is the ability of the user to activate any of several error dispersion sources. The performance of the simulation compares well with more sophisticated simulations.

  17. Multiscale-multiphysics approaches for engineering applications

    Science.gov (United States)

    Pozzetti, Gabriele; Peters, Bernhard

    2017-07-01

    Engineering applications often require the study of complex Multiphysics systems. In order to provide solutions for problems of industrial-environmental interest, methods that can capture the influence of all the different scales of composite phenomena must be developed. Due to these necessities multiscale and multiphysics approaches are rapidly becoming a standard in the mathematical-numerical description of engineering systems. The goal of the symposium is to bring together industrial and environmental researcher and practitioners, in order to discuss techniques that aim to solve this kind of heterogeneous problem in an highly efficient way.

  18. Simulation information regarding Sandia National Laboratories trinity capability improvement metric.

    Energy Technology Data Exchange (ETDEWEB)

    Agelastos, Anthony Michael; Lin, Paul T.

    2013-10-01

    Sandia National Laboratories, Los Alamos National Laboratory, and Lawrence Livermore National Laboratory each selected a representative simulation code to be used as a performance benchmark for the Trinity Capability Improvement Metric. Sandia selected SIERRA Low Mach Module: Nalu, which is a uid dynamics code that solves many variable-density, acoustically incompressible problems of interest spanning from laminar to turbulent ow regimes, since it is fairly representative of implicit codes that have been developed under ASC. The simulations for this metric were performed on the Cielo Cray XE6 platform during dedicated application time and the chosen case utilized 131,072 Cielo cores to perform a canonical turbulent open jet simulation within an approximately 9-billion-elementunstructured- hexahedral computational mesh. This report will document some of the results from these simulations as well as provide instructions to perform these simulations for comparison.

  19. Validation of a 3D multi-physics model for unidirectional silicon solidification

    NARCIS (Netherlands)

    Simons, P.; Lankhorst, A.M.; Habraken, A.; Faber, A.J.; Tiuleanu, D.; Pingel, R.

    2012-01-01

    A model for transient movements of solidification fronts has been added to X-stream, an existing multi-physics simulation program for high temperature processes with flow and chemical reactions. The implementation uses an enthalpy formulation and works on fixed grids. First we show the results of a

  20. Multiphysics pore-scale model for the rehydration of porous foods

    NARCIS (Netherlands)

    Sman, van der R.G.M.; Vergeldt, F.J.; As, van H.; Dalen, van G.; Voda, A.; Duynhoven, van J.P.M.

    2014-01-01

    In this paper we present a pore-scale model describing the multiphysics occurring during the rehydration of freeze-dried vegetables. This pore-scale model is part of a multiscale simulation model, which should explain the effect of microstructure and pre-treatments on the rehydration rate. Simulatio

  1. Scalable Adaptive Multilevel Solvers for Multiphysics Problems

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jinchao [Pennsylvania State Univ., University Park, PA (United States). Dept. of Mathematics

    2014-11-26

    In this project, we carried out many studies on adaptive and parallel multilevel methods for numerical modeling for various applications, including Magnetohydrodynamics (MHD) and complex fluids. We have made significant efforts and advances in adaptive multilevel methods of the multiphysics problems: multigrid methods, adaptive finite element methods, and applications.

  2. Large-Eddy Simulation: Current Capabilities, Recommended Practices, and Future Research

    Science.gov (United States)

    Georgiadis, Nicholas J.; Rizzetta, Donald P.; Fureby, Christer

    2009-01-01

    This paper presents the results of an activity by the Large Eddy Simulation (LES) Working Group of the AIAA Fluid Dynamics Technical Committee to (1) address the current capabilities of LES, (2) outline recommended practices and key considerations for using LES, and (3) identify future research needs to advance the capabilities and reliability of LES for analysis of turbulent flows. To address the current capabilities and future needs, a survey comprised of eleven questions was posed to LES Working Group members to assemble a broad range of perspectives on important topics related to LES. The responses to these survey questions are summarized with the intent not to be a comprehensive dictate on LES, but rather the perspective of one group on some important issues. A list of recommended practices is also provided, which does not treat all aspects of a LES, but provides guidance on some of the key areas that should be considered.

  3. Relativistic modeling capabilities in PERSEUS extended MHD simulation code for HED plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Hamlin, Nathaniel D., E-mail: nh322@cornell.edu [438 Rhodes Hall, Cornell University, Ithaca, NY, 14853 (United States); Seyler, Charles E., E-mail: ces7@cornell.edu [Cornell University, Ithaca, NY, 14853 (United States)

    2014-12-15

    We discuss the incorporation of relativistic modeling capabilities into the PERSEUS extended MHD simulation code for high-energy-density (HED) plasmas, and present the latest hybrid X-pinch simulation results. The use of fully relativistic equations enables the model to remain self-consistent in simulations of such relativistic phenomena as X-pinches and laser-plasma interactions. By suitable formulation of the relativistic generalized Ohm’s law as an evolution equation, we have reduced the recovery of primitive variables, a major technical challenge in relativistic codes, to a straightforward algebraic computation. Our code recovers expected results in the non-relativistic limit, and reveals new physics in the modeling of electron beam acceleration following an X-pinch. Through the use of a relaxation scheme, relativistic PERSEUS is able to handle nine orders of magnitude in density variation, making it the first fluid code, to our knowledge, that can simulate relativistic HED plasmas.

  4. Heat transfer capability simulation of high-temperature heat pipe in supersonic vehicle leading edge applications

    Directory of Open Access Journals (Sweden)

    Donghuan Liu

    2016-04-01

    Full Text Available A numerical method is proposed to determine the heat transfer capability of the high-temperature heat pipe and the stagnation temperature with supersonic vehicle leading edge applications. The finite element method is employed here to perform the temperature field simulation. Without considering the heat transfer limitations of the heat pipe, such as capillary limit and sonic limit, both numerical and experimental results indicate that equivalent high thermal conductivity method is a reasonable way to simulate the heat transfer capability of the high-temperature heat pipe in preliminary design of a heat-pipe-cooled leading edge. Several important parameters’ effects on the thermal protection performance are also numerically investigated.

  5. Addressing Army Aviation Collective Training Challenges with Simulators and Simulations Capabilities

    Science.gov (United States)

    2012-08-01

    Aptima, Inc. Technical Review by William Bickley, U.S. Army Research Institute Heather Priest-Walker, U.S. Army Research Institute...training challenges at home station and at Aviation Training Exercises. This report benefitted from the thoughtful comments of Drs. William Bickley and...environment, cockpit instrumentation, communications, weapons systems, gunnery environment, AH64 TADS , NVG (Night Vision Goggles) Simulation, EDMs

  6. Development, demonstration and implementation of a virtual reality simulation capability for coal mining operations

    Energy Technology Data Exchange (ETDEWEB)

    Chris Fowler; Phil Stothard; Jim Galvin [University of New South Wales, NSW (Australia)

    2005-06-15

    Virtual Reality (VR) simulation refers to the generation of an immersive, interactive, computer generated, three-dimensional environment. As a result of its interactive nature, the VR program senses the user's response to a situation or event. This interaction is reciprocated by the program and feedback to one or more of the user's senses is invoked. This produces the illusion of presence within the simulated environment. VR simulation is a powerful tool for conditioning behaviour. It enables the user to experience a range of situations that might otherwise not be encountered prior to a critical event and conditions the user's response in a safe and forgiving environment. The aim of the project was to develop, demonstrate and transfer a capability in immersive, interactive, virtual reality simulation in order to improve Occupational Health and Safety management and performance in the Australian coal mining sector through the provision of more effective education, training and assessment. Immersive, interactive simulations have developed that relate to 'self escape', 'sprains and strains' and 'rib stability'. All have important Occupational Health and Safety implications that are very dependent on the actions of individuals themselves. The simulations and the technology to utilise them has been transferred to the Australian coal mining industry through the construction of a Virtual Reality Theatre at Newcastle Mines Rescue Station. Recommendations are made as to the how the VR simulation capability that has been established by the project might be further developed and enhanced.

  7. COMSOL Multiphysics Model for HLW Canister Filling

    Energy Technology Data Exchange (ETDEWEB)

    Kesterson, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-04-11

    The U.S. Department of Energy (DOE) is building a Tank Waste Treatment and Immobilization Plant (WTP) at the Hanford Site in Washington to remediate 55 million gallons of radioactive waste that is being temporarily stored in 177 underground tanks. Efforts are being made to increase the loading of Hanford tank wastes in glass while meeting melter lifetime expectancies and process, regulatory, and product quality requirements. Wastes containing high concentrations of Al2O3 and Na2O can contribute to nepheline (generally NaAlSiO4) crystallization, which can sharply reduce the chemical durability of high level waste (HLW) glass. Nepheline crystallization can occur during slow cooling of the glass within the stainless steel canister. The purpose of this work was to develop a model that can be used to predict temperatures of the glass in a WTP HLW canister during filling and cooling. The intent of the model is to support scoping work in the laboratory. It is not intended to provide precise predictions of temperature profiles, but rather to provide a simplified representation of glass cooling profiles within a full scale, WTP HLW canister under various glass pouring rates. These data will be used to support laboratory studies for an improved understanding of the mechanisms of nepheline crystallization. The model was created using COMSOL Multiphysics, a commercially available software. The model results were compared to available experimental data, TRR-PLT-080, and were found to yield sufficient results for the scoping nature of the study. The simulated temperatures were within 60 ºC for the centerline, 0.0762m (3 inch) from centerline, and 0.2286m (9 inch) from centerline thermocouples once the thermocouples were covered with glass. The temperature difference between the experimental and simulated values reduced to 40 ºC, 4 hours after the thermocouple was covered, and down to 20 ºC, 6 hours after the thermocouple was covered

  8. OOFEM — an Object-oriented Simulation Tool for Advanced Modeling of Materials and Structures

    OpenAIRE

    Bořek Patzák

    2012-01-01

    The aim of this paper is to describe the object-oriented design of the finite element based simulation code. The overall, object-oriented structure is described, and the role of the fundamental classes is discussed. The paper discusses the advanced parallel, adaptive, and multiphysics capabilities of the OOFEM code, and illustrates them on the basis of selected examples.

  9. OOFEM — an Object-oriented Simulation Tool for Advanced Modeling of Materials and Structures

    Directory of Open Access Journals (Sweden)

    Bořek Patzák

    2012-01-01

    Full Text Available The aim of this paper is to describe the object-oriented design of the finite element based simulation code. The overall, object-oriented structure is described, and the role of the fundamental classes is discussed. The paper discusses the advanced parallel, adaptive, and multiphysics capabilities of the OOFEM code, and illustrates them on the basis of selected examples.

  10. The DOE Accelerated Strategic Computing Initiative: Challenges and opportunities for predictive materials simulation capabilities

    Science.gov (United States)

    Mailhiot, Christian

    1998-05-01

    In response to the unprecedented national security challenges emerging from the end of nuclear testing, the Defense Programs of the Department of Energy has developed a long-term strategic plan based on a vigorous Science-Based Stockpile Stewardship (SBSS) program. The main objective of the SBSS program is to ensure confidence in the performance, safety, and reliability of the stockpile on the basis of a fundamental science-based approach. A central element of this approach is the development of predictive, ‘full-physics’, full-scale computer simulation tools. As a critical component of the SBSS program, the Accelerated Strategic Computing Initiative (ASCI) was established to provide the required advances in computer platforms and to enable predictive, physics-based simulation capabilities. In order to achieve the ASCI goals, fundamental problems in the fields of computer and physical sciences of great significance to the entire scientific community must be successfully solved. Foremost among the key elements needed to develop predictive simulation capabilities, the development of improved physics-based materials models is a cornerstone. We indicate some of the materials theory, modeling, and simulation challenges and illustrate how the ASCI program will enable both the hardware and the software tools necessary to advance the state-of-the-art in the field of computational condensed matter and materials physics.

  11. Investigating the Mobility of Light Autonomous Tracked Vehicles using a High Performance Computing Simulation Capability

    Science.gov (United States)

    Negrut, Dan; Mazhar, Hammad; Melanz, Daniel; Lamb, David; Jayakumar, Paramsothy; Letherwood, Michael; Jain, Abhinandan; Quadrelli, Marco

    2012-01-01

    This paper is concerned with the physics-based simulation of light tracked vehicles operating on rough deformable terrain. The focus is on small autonomous vehicles, which weigh less than 100 lb and move on deformable and rough terrain that is feature rich and no longer representable using a continuum approach. A scenario of interest is, for instance, the simulation of a reconnaissance mission for a high mobility lightweight robot where objects such as a boulder or a ditch that could otherwise be considered small for a truck or tank, become major obstacles that can impede the mobility of the light autonomous vehicle and negatively impact the success of its mission. Analyzing and gauging the mobility and performance of these light vehicles is accomplished through a modeling and simulation capability called Chrono::Engine. Chrono::Engine relies on parallel execution on Graphics Processing Unit (GPU) cards.

  12. Resolved-particle simulation by the Physalis method: Enhancements and new capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Sierakowski, Adam J., E-mail: sierakowski@jhu.edu [Department of Mechanical Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Prosperetti, Andrea [Department of Mechanical Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Faculty of Science and Technology and J.M. Burgers Centre for Fluid Dynamics, University of Twente, P.O. Box 217, 7500 AE Enschede (Netherlands)

    2016-03-15

    We present enhancements and new capabilities of the Physalis method for simulating disperse multiphase flows using particle-resolved simulation. The current work enhances the previous method by incorporating a new type of pressure-Poisson solver that couples with a new Physalis particle pressure boundary condition scheme and a new particle interior treatment to significantly improve overall numerical efficiency. Further, we implement a more efficient method of calculating the Physalis scalar products and incorporate short-range particle interaction models. We provide validation and benchmarking for the Physalis method against experiments of a sedimenting particle and of normal wall collisions. We conclude with an illustrative simulation of 2048 particles sedimenting in a duct. In the appendix, we present a complete and self-consistent description of the analytical development and numerical methods.

  13. Resolved-particle simulation by the Physalis method: Enhancements and new capabilities

    Science.gov (United States)

    Sierakowski, Adam J.; Prosperetti, Andrea

    2016-03-01

    We present enhancements and new capabilities of the Physalis method for simulating disperse multiphase flows using particle-resolved simulation. The current work enhances the previous method by incorporating a new type of pressure-Poisson solver that couples with a new Physalis particle pressure boundary condition scheme and a new particle interior treatment to significantly improve overall numerical efficiency. Further, we implement a more efficient method of calculating the Physalis scalar products and incorporate short-range particle interaction models. We provide validation and benchmarking for the Physalis method against experiments of a sedimenting particle and of normal wall collisions. We conclude with an illustrative simulation of 2048 particles sedimenting in a duct. In the appendix, we present a complete and self-consistent description of the analytical development and numerical methods.

  14. Adaptive Planning: Understanding Organizational Workload to Capability/ Capacity through Modeling and Simulation

    Science.gov (United States)

    Hase, Chris

    2010-01-01

    In August 2003, the Secretary of Defense (SECDEF) established the Adaptive Planning (AP) initiative [1] with an objective of reducing the time necessary to develop and revise Combatant Commander (COCOM) contingency plans and increase SECDEF plan visibility. In addition to reducing the traditional plan development timeline from twenty-four months to less than twelve months (with a goal of six months)[2], AP increased plan visibility to Department of Defense (DoD) leadership through In-Progress Reviews (IPRs). The IPR process, as well as the increased number of campaign and contingency plans COCOMs had to develop, increased the workload while the number of planners remained fixed. Several efforts from collaborative planning tools to streamlined processes were initiated to compensate for the increased workload enabling COCOMS to better meet shorter planning timelines. This paper examines the Joint Strategic Capabilities Plan (JSCP) directed contingency planning and staffing requirements assigned to a combatant commander staff through the lens of modeling and simulation. The dynamics of developing a COCOM plan are captured with an ExtendSim [3] simulation. The resulting analysis provides a quantifiable means by which to measure a combatant commander staffs workload associated with development and staffing JSCP [4] directed contingency plans with COCOM capability/capacity. Modeling and simulation bring significant opportunities in measuring the sensitivity of key variables in the assessment of workload to capability/capacity analysis. Gaining an understanding of the relationship between plan complexity, number of plans, planning processes, and number of planners with time required for plan development provides valuable information to DoD leadership. Through modeling and simulation AP leadership can gain greater insight in making key decisions on knowing where to best allocate scarce resources in an effort to meet DoD planning objectives.

  15. The capability of lithography simulation based on MVM-SEM® system

    Science.gov (United States)

    Yoshikawa, Shingo; Fujii, Nobuaki; Kanno, Koichi; Imai, Hidemichi; Hayano, Katsuya; Miyashita, Hiroyuki; Shida, Soichi; Murakawa, Tsutomu; Kuribara, Masayuki; Matsumoto, Jun; Nakamura, Takayuki; Matsushita, Shohei; Hara, Daisuke; Pang, Linyong

    2015-10-01

    The 1Xnm technology node lithography is using SMO-ILT, NTD or more complex pattern. Therefore in mask defect inspection, defect verification becomes more difficult because many nuisance defects are detected in aggressive mask feature. One key Technology of mask manufacture is defect verification to use aerial image simulator or other printability simulation. AIMS™ Technology is excellent correlation for the wafer and standards tool for defect verification however it is difficult for verification over hundred numbers or more. We reported capability of defect verification based on lithography simulation with a SEM system that architecture and software is excellent correlation for simple line and space.[1] In this paper, we use a SEM system for the next generation combined with a lithography simulation tool for SMO-ILT, NTD and other complex pattern lithography. Furthermore we will use three dimension (3D) lithography simulation based on Multi Vision Metrology SEM system. Finally, we will confirm the performance of the 2D and 3D lithography simulation based on SEM system for a photomask verification.

  16. The Advanced Modeling, Simulation and Analysis Capability Roadmap Vision for Engineering

    Science.gov (United States)

    Zang, Thomas; Lieber, Mike; Norton, Charles; Fucik, Karen

    2006-01-01

    This paper summarizes a subset of the Advanced Modeling Simulation and Analysis (AMSA) Capability Roadmap that was developed for NASA in 2005. The AMSA Capability Roadmap Team was chartered to "To identify what is needed to enhance NASA's capabilities to produce leading-edge exploration and science missions by improving engineering system development, operations, and science understanding through broad application of advanced modeling, simulation and analysis techniques." The AMSA roadmap stressed the need for integration, not just within the science, engineering and operations domains themselves, but also across these domains. Here we discuss the roadmap element pertaining to integration within the engineering domain, with a particular focus on implications for future observatory missions. The AMSA products supporting the system engineering function are mission information, bounds on information quality, and system validation guidance. The Engineering roadmap element contains 5 sub-elements: (1) Large-Scale Systems Models, (2) Anomalous Behavior Models, (3) advanced Uncertainty Models, (4) Virtual Testing Models, and (5) space-based Robotics Manufacture and Servicing Models.

  17. Induction Heating Process Design Using COMSOL Multiphysics Software

    Directory of Open Access Journals (Sweden)

    Andy Triwinarko

    2011-08-01

    Full Text Available Induction heating is clean environmental heating process due to a non-contact heating process. There is lots of the induction heating type that be used in the home appliance but it is still new technology in Indonesia. The main interesting area of the induction heating design is the efficiency of the usage of energy and choice of the plate material. COMSOL Multiphysics Software can be used to simulate and estimate the induction heating process. Therefore, the software can be used to design the induction heating process that will have a optimum efficiency. The properties of the induction heating design were also simulated and analyzed such as effect of inductors width, inductors distance, and conductive plate material. The result was shown that the good design of induction heating must have a short width and distance inductor and used silicon carbide as material plate with high frequency controller.

  18. Exploring JWST's Capability to Constrain Habitability on Simulated Terrestrial TESS Planets

    Science.gov (United States)

    Tremblay, Luke; Britt, Amber; Batalha, Natasha; Schwieterman, Edward; Arney, Giada; Domagal-Goldman, Shawn; Mandell, Avi; Planetary Systems Laboratory; Virtual Planetary Laboratory

    2017-01-01

    In the following, we have worked to develop a flexible "observability" scale of biologically relevant molecules in the atmospheres of newly discovered exoplanets for the instruments aboard NASA's next flagship mission, the James Webb Space Telescope (JWST). We sought to create such a scale in order to provide the community with a tool with which to optimize target selection for JWST observations based on detections of the upcoming Transiting Exoplanet Satellite Survey (TESS). Current literature has laid the groundwork for defining both biologically relevant molecules as well as what characteristics would make a new world "habitable", but it has so far lacked a cohesive analysis of JWST's capabilities to observe these molecules in exoplanet atmospheres and thereby constrain habitability. In developing our Observability Scale, we utilized a range of hypothetical planets (over planetary radii and stellar insolation) and generated three self-consistent atmospheric models (of dierent molecular compositions) for each of our simulated planets. With these planets and their corresponding atmospheres, we utilized the most accurate JWST instrument simulator, created specically to process transiting exoplanet spectra. Through careful analysis of these simulated outputs, we were able to determine the relevant parameters that effected JWST's ability to constrain each individual molecular bands with statistical accuracy and therefore generate a scale based on those key parameters. As a preliminary test of our Observability Scale, we have also applied it to the list of TESS candidate stars in order to determine JWST's observational capabilities for any soon-to-be-detected planet in those solar systems.

  19. Multiphysical Testing of Soils and Shales

    CERN Document Server

    Ferrari, Alessio

    2013-01-01

    Significant advancements in the experimental analysis of soils and shales have been achieved during the last few decades. Outstanding progress in the field has led to the theoretical development of geomechanical theories and important engineering applications. This book provides the reader with an overview of recent advances in a variety of advanced experimental techniques and results for the analysis of the behaviour of geomaterials under multiphysical testing conditions. Modern trends in experimental geomechanics for soils and shales are discussed, including testing materials in variably saturated conditions, non-isothermal experiments, micro-scale investigations and image analysis techniques. Six theme papers from leading researchers in experimental geomechanics are also included. This book is intended for postgraduate students, researchers and practitioners in fields where multiphysical testing of soils and shales plays a fundamental role, such as unsaturated soil and rock mechanics, petroleum engineering...

  20. High-fidelity simulation capability for virtual testing of seismic and acoustic sensors

    Science.gov (United States)

    Wilson, D. Keith; Moran, Mark L.; Ketcham, Stephen A.; Lacombe, James; Anderson, Thomas S.; Symons, Neill P.; Aldridge, David F.; Marlin, David H.; Collier, Sandra L.; Ostashev, Vladimir E.

    2005-05-01

    This paper describes development and application of a high-fidelity, seismic/acoustic simulation capability for battlefield sensors. The purpose is to provide simulated sensor data so realistic that they cannot be distinguished by experts from actual field data. This emerging capability provides rapid, low-cost trade studies of unattended ground sensor network configurations, data processing and fusion strategies, and signatures emitted by prototype vehicles. There are three essential components to the modeling: (1) detailed mechanical signature models for vehicles and walkers, (2) high-resolution characterization of the subsurface and atmospheric environments, and (3) state-of-the-art seismic/acoustic models for propagating moving-vehicle signatures through realistic, complex environments. With regard to the first of these components, dynamic models of wheeled and tracked vehicles have been developed to generate ground force inputs to seismic propagation models. Vehicle models range from simple, 2D representations to highly detailed, 3D representations of entire linked-track suspension systems. Similarly detailed models of acoustic emissions from vehicle engines are under development. The propagation calculations for both the seismics and acoustics are based on finite-difference, time-domain (FDTD) methodologies capable of handling complex environmental features such as heterogeneous geologies, urban structures, surface vegetation, and dynamic atmospheric turbulence. Any number of dynamic sources and virtual sensors may be incorporated into the FDTD model. The computational demands of 3D FDTD simulation over tactical distances require massively parallel computers. Several example calculations of seismic/acoustic wave propagation through complex atmospheric and terrain environments are shown.

  1. Validation and Calibration of Nuclear Thermal Hydraulics Multiscale Multiphysics Models - Subcooled Flow Boiling Study

    Energy Technology Data Exchange (ETDEWEB)

    Anh Bui; Nam Dinh; Brian Williams

    2013-09-01

    In addition to validation data plan, development of advanced techniques for calibration and validation of complex multiscale, multiphysics nuclear reactor simulation codes are a main objective of the CASL VUQ plan. Advanced modeling of LWR systems normally involves a range of physico-chemical models describing multiple interacting phenomena, such as thermal hydraulics, reactor physics, coolant chemistry, etc., which occur over a wide range of spatial and temporal scales. To a large extent, the accuracy of (and uncertainty in) overall model predictions is determined by the correctness of various sub-models, which are not conservation-laws based, but empirically derived from measurement data. Such sub-models normally require extensive calibration before the models can be applied to analysis of real reactor problems. This work demonstrates a case study of calibration of a common model of subcooled flow boiling, which is an important multiscale, multiphysics phenomenon in LWR thermal hydraulics. The calibration process is based on a new strategy of model-data integration, in which, all sub-models are simultaneously analyzed and calibrated using multiple sets of data of different types. Specifically, both data on large-scale distributions of void fraction and fluid temperature and data on small-scale physics of wall evaporation were simultaneously used in this work’s calibration. In a departure from traditional (or common-sense) practice of tuning/calibrating complex models, a modern calibration technique based on statistical modeling and Bayesian inference was employed, which allowed simultaneous calibration of multiple sub-models (and related parameters) using different datasets. Quality of data (relevancy, scalability, and uncertainty) could be taken into consideration in the calibration process. This work presents a step forward in the development and realization of the “CIPS Validation Data Plan” at the Consortium for Advanced Simulation of LWRs to enable

  2. Towards enhancing Sandia's capabilities in multiscale materials modeling and simulation.

    Energy Technology Data Exchange (ETDEWEB)

    Aidun, John Bahram; Fang, Huei Eliot; Barbour, John Charles; Westrich, Henry Roger; Chen, Er-Ping

    2004-01-01

    We report our conclusions in support of the FY 2003 Science and Technology Milestone ST03-3.5. The goal of the milestone was to develop a research plan for expanding Sandia's capabilities in materials modeling and simulation. From inquiries and discussion with technical staff during FY 2003 we conclude that it is premature to formulate the envisioned coordinated research plan. The more appropriate goal is to develop a set of computational tools for making scale transitions and accumulate experience with applying these tools to real test cases so as to enable us to attack each new problem with higher confidence of success.

  3. Investigating Darcy-scale assumptions by means of a multiphysics algorithm

    Science.gov (United States)

    Tomin, Pavel; Lunati, Ivan

    2016-09-01

    Multiphysics (or hybrid) algorithms, which couple Darcy and pore-scale descriptions of flow through porous media in a single numerical framework, are usually employed to decrease the computational cost of full pore-scale simulations or to increase the accuracy of pure Darcy-scale simulations when a simple macroscopic description breaks down. Despite the massive increase in available computational power, the application of these techniques remains limited to core-size problems and upscaling remains crucial for practical large-scale applications. In this context, the Hybrid Multiscale Finite Volume (HMsFV) method, which constructs the macroscopic (Darcy-scale) problem directly by numerical averaging of pore-scale flow, offers not only a flexible framework to efficiently deal with multiphysics problems, but also a tool to investigate the assumptions used to derive macroscopic models and to better understand the relationship between pore-scale quantities and the corresponding macroscale variables. Indeed, by direct comparison of the multiphysics solution with a reference pore-scale simulation, we can assess the validity of the closure assumptions inherent to the multiphysics algorithm and infer the consequences for macroscopic models at the Darcy scale. We show that the definition of the scale ratio based on the geometric properties of the porous medium is well justified only for single-phase flow, whereas in case of unstable multiphase flow the nonlinear interplay between different forces creates complex fluid patterns characterized by new spatial scales, which emerge dynamically and weaken the scale-separation assumption. In general, the multiphysics solution proves very robust even when the characteristic size of the fluid-distribution patterns is comparable with the observation length, provided that all relevant physical processes affecting the fluid distribution are considered. This suggests that macroscopic constitutive relationships (e.g., the relative

  4. Development of Virtual Airspace Simulation Technology - Real-Time (VAST-RT) Capability 2 and Experimental Plans

    Science.gov (United States)

    Lehmer, R.; Ingram, C.; Jovic, S.; Alderete, J.; Brown, D.; Carpenter, D.; LaForce, S.; Panda, R.; Walker, J.; Chaplin, P.; hide

    2006-01-01

    The Virtual Airspace Simulation Technology - Real-Time (VAST-RT) Project, an element cf NASA's Virtual Airspace Modeling and Simulation (VAMS) Project, has been developing a distributed simulation capability that supports an extensible and expandable real-time, human-in-the-loop airspace simulation environment. The VAST-RT system architecture is based on DoD High Level Architecture (HLA) and the VAST-RT HLA Toolbox, a common interface implementation that incorporates a number of novel design features. The scope of the initial VAST-RT integration activity (Capability 1) included the high-fidelity human-in-the-loop simulation facilities located at NASA/Ames Research Center and medium fidelity pseudo-piloted target generators, such as the Airspace Traffic Generator (ATG) being developed as part of VAST-RT, as well as other real-time tools. This capability has been demonstrated in a gate-to-gate simulation. VAST-RT's (Capability 2A) has been recently completed, and this paper will discuss the improved integration of the real-time assets into VAST-RT, including the development of tools to integrate data collected across the simulation environment into a single data set for the researcher. Current plans for the completion of the VAST-RT distributed simulation environment (Capability 2B) and its use to evaluate future airspace capacity enhancing concepts being developed by VAMS will be discussed. Additionally, the simulation environment's application to other airspace and airport research projects is addressed.

  5. Multilingual interfaces for parallel coupling in multiphysics and multiscale systems.

    Energy Technology Data Exchange (ETDEWEB)

    Ong, E. T.; Larson, J. W.; Norris, B.; Jacob, R. L.; Tobis, M.; Steder, M.; Mathematics and Computer Science; Univ. of Wisconsin; Australian National Univ.; Univ. of Chicago

    2007-01-01

    Multiphysics and multiscale simulation systems are emerging as a new grand challenge in computational science, largely because of increased computing power provided by the distributed-memory parallel programming model on commodity clusters. These systems often present a parallel coupling problem in their intercomponent data exchanges. Another potential problem in these coupled systems is language interoperability between their various constituent codes. In anticipation of combined parallel coupling/language interoperability challenges, we have created a set of interlanguage bindings for a successful parallel coupling library, the Model Coupling Toolkit. We describe the method used for automatically generating the bindings using the Babel language interoperability tool, and illustrate with short examples how MCT can be used from the C++ and Python languages. We report preliminary performance reports for the MCT interpolation benchmark. We conclude with a discussion of the significance of this work to the rapid prototyping of large parallel coupled systems.

  6. A Global Sensitivity Analysis Methodology for Multi-physics Applications

    Energy Technology Data Exchange (ETDEWEB)

    Tong, C H; Graziani, F R

    2007-02-02

    Experiments are conducted to draw inferences about an entire ensemble based on a selected number of observations. This applies to both physical experiments as well as computer experiments, the latter of which are performed by running the simulation models at different input configurations and analyzing the output responses. Computer experiments are instrumental in enabling model analyses such as uncertainty quantification and sensitivity analysis. This report focuses on a global sensitivity analysis methodology that relies on a divide-and-conquer strategy and uses intelligent computer experiments. The objective is to assess qualitatively and/or quantitatively how the variabilities of simulation output responses can be accounted for by input variabilities. We address global sensitivity analysis in three aspects: methodology, sampling/analysis strategies, and an implementation framework. The methodology consists of three major steps: (1) construct credible input ranges; (2) perform a parameter screening study; and (3) perform a quantitative sensitivity analysis on a reduced set of parameters. Once identified, research effort should be directed to the most sensitive parameters to reduce their uncertainty bounds. This process is repeated with tightened uncertainty bounds for the sensitive parameters until the output uncertainties become acceptable. To accommodate the needs of multi-physics application, this methodology should be recursively applied to individual physics modules. The methodology is also distinguished by an efficient technique for computing parameter interactions. Details for each step will be given using simple examples. Numerical results on large scale multi-physics applications will be available in another report. Computational techniques targeted for this methodology have been implemented in a software package called PSUADE.

  7. Research Capabilities for Oil-Free Turbomachinery Expanded by New Rotordynamic Simulator Facility

    Science.gov (United States)

    Howard, Samuel A.

    2004-01-01

    A new test rig has been developed for simulating high-speed turbomachinery shafting using Oil-Free foil air bearing technology. Foil air journal bearings are self-acting hydrodynamic bearings with a flexible inner sleeve surface using air as the lubricant. These bearings have been used in turbomachinery, primarily air cycle machines, for the past four decades to eliminate the need for oil lubrication. More recently, interest has been growing in applying foil bearings to aircraft gas turbine engines. They offer potential improvements in efficiency and power density, decreased maintenance costs, and other secondary benefits. The goal of applying foil air bearings to aircraft gas turbine engines prompted the fabrication of this test rig. The facility enables bearing designers to test potential bearing designs with shafts that simulate the rotating components of a target engine without the high cost of building actual flight hardware. The data collected from this rig can be used to make changes to the shaft and bearings in subsequent design iterations. The rest of this article describes the new test rig and demonstrates some of its capabilities with an initial simulated shaft system. The test rig has two support structures, each housing a foil air journal bearing. The structures are designed to accept any size foil journal bearing smaller than 63 mm (2.5 in.) in diameter. The bearing support structures are mounted to a 91- by 152-cm (3- by 5-ft) table and can be separated by as much as 122 cm (4 ft) and as little as 20 cm (8 in.) to accommodate a wide range of shaft sizes. In the initial configuration, a 9.5-cm (3.75-in.) impulse air turbine drives the test shaft. The impulse turbine, as well as virtually any number of "dummy" compressor and turbine disks, can be mounted on the shaft inboard or outboard of the bearings. This flexibility allows researchers to simulate various engine shaft configurations. The bearing support structures include a unique bearing mounting

  8. Numerical simulation of mold-filling capability for a thin- walled aluminum die casting

    Science.gov (United States)

    Sun, L.; Subasic, E.; Jakumeit, J.

    2015-06-01

    Mold-filling capability is an important property of casting materials. Especially in thin-walled die casting, fast cooling of the melt by contact to the die makes complete filling difficult to ensure. Simulation is an important tool enabling investigation of filling problems, even before the die is manufactured. However, the prediction of misruns is challenging. Flow and solidification have to be computed as closely coupled. The effects of surface tension, the wetting angle and reduced melt flow due to solidification must be modeled with high precision. To meet these requirements, a finite-volume method using arbitrary polyhedral control volumes is used to solve flow and solidification as closely coupled. The Volume-of-Fluid approach is used to capture the phase separation between gas, melt and solid in connection with a High-Resolution Interface-Capturing scheme to obtain sharp interfaces between phases. To model the resistance of the dendrite network to the melt flow, an additional source term in the momentum equation was implemented. The Bolt test was performed for A356 alloys at a range of different casting temperatures. Numerical prediction of incomplete filling in the bottleneck regions agreed well with experimental findings using 3D camera scanning. The simulation enables derivation of the dependence of critical wall-thickness, i.e. the thickness which is fillable, on casting temperature and metallostatic pressure. This could prove useful in predicting filling problems ahead of casting.

  9. Multiphysics Model Development and the Core Analysis for In Situ Breeding and Burning Reactor

    Directory of Open Access Journals (Sweden)

    Shengyi Si

    2013-01-01

    Full Text Available The in situ breeding and burning reactor (ISBBR, which makes use of the outstanding breeding capability of metallic pellet and the excellent irradiation-resistant performance of SiCf/SiC ceramic composites cladding, can approach the design purpose of ultralong cycle and ultrahigh burnup and maintain stable radial power distribution during the cycle life without refueling and shuffling. Since the characteristics of the fuel pellet and cladding are different from the traditional fuel rod of ceramic pellet and metallic cladding, the multiphysics behaviors in ISBBR are also quite different. A computer code, named TANG, to model the specific multiphysics behaviors in ISBBR has been developed. The primary calculation results provided by TANG demonstrate that ISBBR has an excellent comprehensive performance of GEN-IV and a great development potential.

  10. Reliability-based design optimization of multiphysics, aerospace systems

    Science.gov (United States)

    Allen, Matthew R.

    Aerospace systems are inherently plagued by uncertainties in their design, fabrication, and operation. Safety factors and expensive testing at the prototype level traditionally account for these uncertainties. Reliability-based design optimization (RBDO) can drastically decrease life-cycle development costs by accounting for the stochastic nature of the system response in the design process. The reduction in cost is amplified for conceptually new designs, for which no accepted safety factors currently exist. Aerospace systems often operate in environments dominated by multiphysics phenomena, such as the fluid-structure interaction of aeroelastic wings or the electrostatic-mechanical interaction of sensors and actuators. The analysis of such phenomena is generally complex and computationally expensive, and therefore is usually simplified or approximated in the design process. However, this leads to significant epistemic uncertainties in modeling, which may dominate the uncertainties for which the reliability analysis was intended. Therefore, the goal of this thesis is to present a RBDO framework that utilizes high-fidelity simulation techniques to minimize the modeling error for multiphysics phenomena. A key component of the framework is an extended reduced order modeling (EROM) technique that can analyze various states in the design or uncertainty parameter space at a reduced computational cost, while retaining characteristics of high-fidelity methods. The computational framework is verified and applied to the RBDO of aeroelastic systems and electrostatically driven sensors and actuators, utilizing steady-state analysis and design criteria. The framework is also applied to the design of electrostatic devices with transient criteria, which requires the use of the EROM technique to overcome the computational burden of multiple transient analyses.

  11. 3D visual analysis tool in support of the SANDF's growing ground based air defence simulation capability

    CSIR Research Space (South Africa)

    Duvenhage, B

    2007-10-01

    Full Text Available A 3D visual analysis tool has been developed to add value to the SANDF's growing Ground Based Air Defence (GBAD) System of Systems simulation capability. A time based XML interface between the simulation and analysis tool, via a TCP connection or a...

  12. Multiphysics Nuclear Thermal Rocket Thrust Chamber Analysis

    Science.gov (United States)

    Wang, Ten-See

    2005-01-01

    The objective of this effort is t o develop an efficient and accurate thermo-fluid computational methodology to predict environments for hypothetical thrust chamber design and analysis. The current task scope is to perform multidimensional, multiphysics analysis of thrust performance and heat transfer analysis for a hypothetical solid-core, nuclear thermal engine including thrust chamber and nozzle. The multiphysics aspects of the model include: real fluid dynamics, chemical reactivity, turbulent flow, and conjugate heat transfer. The model will be designed to identify thermal, fluid, and hydrogen environments in all flow paths and materials. This model would then be used to perform non- nuclear reproduction of the flow element failures demonstrated in the Rover/NERVA testing, investigate performance of specific configurations and assess potential issues and enhancements. A two-pronged approach will be employed in this effort: a detailed analysis of a multi-channel, flow-element, and global modeling of the entire thrust chamber assembly with a porosity modeling technique. It is expected that the detailed analysis of a single flow element would provide detailed fluid, thermal, and hydrogen environments for stress analysis, while the global thrust chamber assembly analysis would promote understanding of the effects of hydrogen dissociation and heat transfer on thrust performance. These modeling activities will be validated as much as possible by testing performed by other related efforts.

  13. NREL Multiphysics Modeling Tools and ISC Device for Designing Safer Li-Ion Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Pesaran, Ahmad A.; Yang, Chuanbo

    2016-03-24

    The National Renewable Energy Laboratory has developed a portfolio of multiphysics modeling tools to aid battery designers better understand the response of lithium ion batteries to abusive conditions. We will discuss this portfolio, which includes coupled electrical, thermal, chemical, electrochemical, and mechanical modeling. These models can simulate the response of a cell to overheating, overcharge, mechanical deformation, nail penetration, and internal short circuit. Cell-to-cell thermal propagation modeling will be discussed.

  14. Report on Thermal Neutron Diffusion Length Measurement in Reactor Grade Graphite Using MCNP and COMSOL Multiphysics

    OpenAIRE

    2013-01-01

    Neutron diffusion length in reactor grade graphite is measured both experimentally and theoretically. The experimental work includes Monte Carlo (MC) coding using 'MCNP' and Finite Element Analysis (FEA) coding suing 'COMSOL Multiphysics' and Matlab. The MCNP code is adopted to simulate the thermal neutron diffusion length in a reactor moderator of 2m x 2m with slightly enriched uranium ($^{235}U$), accompanied with a model designed for thermal hydraulic analysis using point kinetic equations...

  15. Determination of Thermal Properties of Fresh Water and Sea Water Ice using Multiphysics Analysis

    OpenAIRE

    Rashid, T.; KHAWAJA, H.; K Edvardsen

    2016-01-01

    Publisher's version, source: http://dx.doi.org/10.21152/1750-9548.10.3.277. This paper presents a methodology to determine the thermal conductivity of ice using multiphysics analysis. This methodology used a combination of both experimentation and numerical simulation. In the experimental work, an ice block is observed using an infrared camera. The results reveal the variation in temperature over the surface. These results are dependent on two primary heat transfer parameters, namely, cond...

  16. Report on Thermal Neutron Diffusion Length Measurement in Reactor Grade Graphite Using MCNP and COMSOL Multiphysics

    CERN Document Server

    Mirfayzi, S R

    2013-01-01

    Neutron diffusion length in reactor grade graphite is measured both experimentally and theoretically. The experimental work includes Monte Carlo (MC) coding using 'MCNP' and Finite Element Analysis (FEA) coding suing 'COMSOL Multiphysics' and Matlab. The MCNP code is adopted to simulate the thermal neutron diffusion length in a reactor moderator of 2m x 2m with slightly enriched uranium ($^{235}U$), accompanied with a model designed for thermal hydraulic analysis using point kinetic equations, based on partial and ordinary differential equation. The theoretical work includes numerical approximation methods including transcendental technique to illustrate the iteration process with the FEA method. Finally collision density of thermal neutron in graphite is measured, also specific heat relation dependability of collision density is also calculated theoretically, the thermal neutron diffusion length in graphite is evaluated at $50.85 \\pm 0.3cm$ using COMSOL Multiphysics and $50.95 \\pm 0.5cm$ using MCNP. Finally ...

  17. Multiphysics Modelling of the Mandel- Cryer Effect

    Directory of Open Access Journals (Sweden)

    E Holzbecher

    2016-03-01

    Full Text Available In porous medium studies the Mandel-Cryer effect is known, describing non-monotonic pore-water pressure evolution in response to loading or to changed stress conditions. In a 2D poro-elastic model we couple the pore water hydraulics with mechanics (HM. The Mandel-Cryer effect is identified in parts of the model region that are far from the drainage boundary. At parts of the loaded boundary an even more complex pressure evolution is revealed. Variations of the Biot-parameter as the coupling parameter clearly indicate the relevance of the two-way coupling between the involved physical regimes. Hence the Mandel-Cryer effect is a typical result of multi-physical coupling.

  18. ENHANCED THERMAL VACUUM TEST CAPABILITY FOR RADIOISOTOPE POWER SYSTEMS AT THE IDAHO NATIONAL LABORATORY BETTER SIMULATES ENVIRONMENTAL CONDITIONS OF SPACE

    Energy Technology Data Exchange (ETDEWEB)

    J. C. Giglio; A. A. Jackson

    2012-03-01

    The Idaho National Laboratory (INL) is preparing to fuel and test the Advanced Stirling Radioisotope Generator (ASRG), the next generation space power generator. The INL identified the thermal vacuum test chamber used to test past generators as inadequate. A second vacuum chamber was upgraded with a thermal shroud to process the unique needs and to test the full power capability of the new generator. The thermal vacuum test chamber is the first of its kind capable of testing a fueled power system to temperature that accurately simulate space. This paper outlines the new test and set up capabilities at the INL.

  19. ENHANCED THERMAL VACUUM TEST CAPABILITY FOR RADIOISOTOPE POWER SYSTEMS AT THE IDAHO NATIONAL LABORATORY BETTER SIMULATES ENVIRONMENTAL CONDITIONS OF SPACE

    Energy Technology Data Exchange (ETDEWEB)

    J. C. Giglio; A. A. Jackson

    2012-03-01

    The Idaho National Laboratory (INL) is preparing to fuel and test the Advanced Stirling Radioisotope Generator (ASRG), the next generation space power generator. The INL identified the thermal vacuum test chamber used to test past generators as inadequate. A second vacuum chamber was upgraded with a thermal shroud to process the unique needs and to test the full power capability of the new generator. The thermal vacuum test chamber is the first of its kind capable of testing a fueled power system to temperature that accurately simulate space. This paper outlines the new test and set up capabilities at the INL.

  20. Isolation of bacteria from Siberian permafrost capable of growing under simulated Mars atmospheric pressure and composition

    Science.gov (United States)

    Nicholson, Wayne; Gilichinsky, David; Schuerger, Andrew; Mironov, Vasiliy; Fajardo-Cavazos, Patricia; Kerney, Krystal; Krivushin, Kirill; Oliveira, Rafael; Waters, Samantha

    A central goal of Astrobiology is to explore the limits at which life can occur and to search for life and habitable locations outside Earth. Mars is currently an active target in the search for life due to its relative proximity and similarity to Earth, coupled with increasing evidence pointing to the past and present existence of liquid water at the surface and near subsurface [1]. Exchange of rocky impact ejecta between Mars and Earth has been known for at least two decades [2], and evidence has accumulated supporting the hypothesis that living microorganisms embedded in rocks could survive the transfer process [3]. Understanding the ability of terrestrial microbes to grow in the near-surface martian environment is of prime importance both for life detection and for protection of Mars from forward contamination by human or robotic exploration [4]. The surface environment of Mars presents formidable challenges to life, such as: harsh solar radiation; a scarcity of liquid water and nutrients; extreme low temperatures; and a low-pressure, CO2-dominated anoxic atmosphere [5]. Our recent work has concentrated on investigating the possibility that prokaryotes from Earth could survive and proliferate in the Mars environment. Our experiments have involved environmental chambers that can simulate Mars atmospheric conditions of low pressure (P; 0.7 kPa), temperature (T; 0˚C), and a CO2-dominated anoxic atmosphere (A), called here collectively low-PTA conditions. Because much of the water on present-day Mars exists in a permanently frozen state mixed with mineral matrix, terrestrial permafrosts are considered to be analogs of the martian environment [6]. We therefore screened Siberian permafrost soils for microbes capable of growing under low-PTA conditions. Using this approach we reported the isolation of 6 Carnobacterium spp. isolates from Siberian permafrost that were capable of low-PTA growth [7]. One of these isolates has been characterized in detail and proposed as

  1. Advances in time-domain electromagnetic simulation capabilities through the use of overset grids and massively parallel computing

    Science.gov (United States)

    Blake, Douglas Clifton

    A new methodology is presented for conducting numerical simulations of electromagnetic scattering and wave-propagation phenomena on massively parallel computing platforms. A process is constructed which is rooted in the Finite-Volume Time-Domain (FVTD) technique to create a simulation capability that is both versatile and practical. In terms of versatility, the method is platform independent, is easily modifiable, and is capable of solving a large number of problems with no alterations. In terms of practicality, the method is sophisticated enough to solve problems of engineering significance and is not limited to mere academic exercises. In order to achieve this capability, techniques are integrated from several scientific disciplines including computational fluid dynamics, computational electromagnetics, and parallel computing. The end result is the first FVTD solver capable of utilizing the highly flexible overset-gridding process in a distributed-memory computing environment. In the process of creating this capability, work is accomplished to conduct the first study designed to quantify the effects of domain-decomposition dimensionality on the parallel performance of hyperbolic partial differential equations solvers; to develop a new method of partitioning a computational domain comprised of overset grids; and to provide the first detailed assessment of the applicability of overset grids to the field of computational electromagnetics. Using these new methods and capabilities, results from a large number of wave propagation and scattering simulations are presented. The overset-grid FVTD algorithm is demonstrated to produce results of comparable accuracy to single-grid simulations while simultaneously shortening the grid-generation process and increasing the flexibility and utility of the FVTD technique. Furthermore, the new domain-decomposition approaches developed for overset grids are shown to be capable of producing partitions that are better load balanced and

  2. Advanced Simulation Capability for Turbopump Cavitation Dynamics Guided by Experimental Validation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Numerical cavitation modeling capability is critical in the design of liquid rocket engine turbopumps, feed lines, injector manifolds and engine test facilities....

  3. 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

  4. AFHRL/FT [Air Force Human Resources Laboratory/Flight Training] Capabilities in Undergraduate Pilot Training Simulation Research: Executive Summary.

    Science.gov (United States)

    Matheny, W. G.; And Others

    The document presents a summary description of the Air Force Human Resource Laboratory's Flying Training Division (AFHRL/FT) research capabilities for undergraduate pilot training. One of the research devices investigated is the Advanced Simulator for Undergraduate Pilot Training (ASUPT). The equipment includes the ASUPT, the instrumented T-37…

  5. Multiscale multiphysics and multidomain models--flexibility and rigidity.

    Science.gov (United States)

    Xia, Kelin; Opron, Kristopher; Wei, Guo-Wei

    2013-11-21

    The emerging complexity of large macromolecules has led to challenges in their full scale theoretical description and computer simulation. Multiscale multiphysics and multidomain models have been introduced to reduce the number of degrees of freedom while maintaining modeling accuracy and achieving computational efficiency. A total energy functional is constructed to put energies for polar and nonpolar solvation, chemical potential, fluid flow, molecular mechanics, and elastic dynamics on an equal footing. The variational principle is utilized to derive coupled governing equations for the above mentioned multiphysical descriptions. Among these governing equations is the Poisson-Boltzmann equation which describes continuum electrostatics with atomic charges. The present work introduces the theory of continuum elasticity with atomic rigidity (CEWAR). The essence of CEWAR is to formulate the shear modulus as a continuous function of atomic rigidity. As a result, the dynamics complexity of a macromolecular system is separated from its static complexity so that the more time-consuming dynamics is handled with continuum elasticity theory, while the less time-consuming static analysis is pursued with atomic approaches. We propose a simple method, flexibility-rigidity index (FRI), to analyze macromolecular flexibility and rigidity in atomic detail. The construction of FRI relies on the fundamental assumption that protein functions, such as flexibility, rigidity, and energy, are entirely determined by the structure of the protein and its environment, although the structure is in turn determined by all the interactions. As such, the FRI measures the topological connectivity of protein atoms or residues and characterizes the geometric compactness of the protein structure. As a consequence, the FRI does not resort to the interaction Hamiltonian and bypasses matrix diagonalization, which underpins most other flexibility analysis methods. FRI's computational complexity is of O

  6. Multiphysics and multiscale modelling of ductile cast iron solidification

    Directory of Open Access Journals (Sweden)

    D. Gurgul

    2010-01-01

    Full Text Available The presented model of ductile cast iron solidification is a typical sample of multiphysics and multiscale engineering system. This model takes into consideration the different time and spatial scales of accounted phenomenon of microstructure formation: heat diffusion, components mass diffusion in the liquid and solid phases, thermodynamic of phase transformation under the condition of inhomogeneous chemical composition of growing and vanishing phases, phase interface kinetics and grains nucleation.The results of two-dimensional modelling of the microstructure formation in the ductile cast iron (so called - Ductile Iron - DI are pre-sented. The cellular automaton model (CA was used for the simulation. Six states of CA cells were adopted to three phases above men-tioned (liquid, austenite and graphite and to three two-phase interfaces. For the modelling of concentration and temperature fields the numerical solution was used. The parabolic nonlinear differential equa-tions with a source term were solved by using the finite difference method and explicit scheme. The overlapping lattices with the same spatial step were used for the concentration field modelling and for the CA. The time scale of the temperature field for this lattice is about 104 times shorter. Due to above reasons the another lattice was used with a multiple spatial step and the same time step.

  7. Multiphysics methods development for high temperature gas reactor analysis

    Science.gov (United States)

    Seker, Volkan

    Multiphysics computational methods were developed to perform design and safety analysis of the next generation Pebble Bed High Temperature Gas Cooled Reactors. A suite of code modules was developed to solve the coupled thermal-hydraulics and neutronics field equations. The thermal-hydraulics module is based on the three dimensional solution of the mass, momentum and energy equations in cylindrical coordinates within the framework of the porous media method. The neutronics module is a part of the PARCS (Purdue Advanced Reactor Core Simulator) code and provides a fine mesh finite difference solution of the neutron diffusion equation in three dimensional cylindrical coordinates. Coupling of the two modules was performed by mapping the solution variables from one module to the other. Mapping is performed automatically in the code system by the use of a common material mesh in both modules. The standalone validation of the thermal-hydraulics module was performed with several cases of the SANA experiment and the standalone thermal-hydraulics exercise of the PBMR-400 benchmark problem. The standalone neutronics module was validated by performing the relevant exercises of the PBMR-268 and PBMR-400 benchmark problems. Additionally, the validation of the coupled code system was performed by analyzing several steady state and transient cases of the OECD/NEA PBMR-400 benchmark problem.

  8. Prototype Development Capabilities of 3D Spatial Interactions and Failures During Scenario Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Steven Prescott; Ramprasad Sampath; Curtis Smith; Tony Koonce

    2014-09-01

    Computers have been used for 3D modeling and simulation, but only recently have computational resources been able to give realistic results in a reasonable time frame for large complex models. This report addressed the methods, techniques, and resources used to develop a prototype for using 3D modeling and simulation engine to improve risk analysis and evaluate reactor structures and components for a given scenario. The simulations done for this evaluation were focused on external events, specifically tsunami floods, for a hypothetical nuclear power facility on a coastline.

  9. Assessment of Capabilities for First-Principles Simulation of Spacecraft Electric Propulsion Systems and Plasma Spacecraft Environment

    Science.gov (United States)

    2016-04-29

    other provision of law , no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a...Briefing Charts 3. DATES COVERED (From - To) 05 April 2016 – 29 April 2016 4. TITLE AND SUBTITLE Assessment of Capabilities for First- Principles ...Simulation of Spacecraft Electric Propulsion Systems and Plasma Spacecraft Environment 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT

  10. Joint Command and Control (JC2) capability development utilising a Modelling and Simulation Framework

    CSIR Research Space (South Africa)

    Ramadeen, P

    2010-09-01

    Full Text Available : situational picture management; data and sensor fusion; user interaction; tactical simulation; incident management; and system interoperability. Applications developed with the framework can be executed and distributed over multiple hosts through a proprietary...

  11. Uncertainty quantification's role in modeling and simulation planning, and credibility assessment through the predictive capability maturity model

    Energy Technology Data Exchange (ETDEWEB)

    Rider, William J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Witkowski, Walter R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mousseau, Vincent Andrew [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-04-13

    The importance of credible, trustworthy numerical simulations is obvious especially when using the results for making high-consequence decisions. Determining the credibility of such numerical predictions is much more difficult and requires a systematic approach to assessing predictive capability, associated uncertainties and overall confidence in the computational simulation process for the intended use of the model. This process begins with an evaluation of the computational modeling of the identified, important physics of the simulation for its intended use. This is commonly done through a Phenomena Identification Ranking Table (PIRT). Then an assessment of the evidence basis supporting the ability to computationally simulate these physics can be performed using various frameworks such as the Predictive Capability Maturity Model (PCMM). There were several critical activities that follow in the areas of code and solution verification, validation and uncertainty quantification, which will be described in detail in the following sections. Here, we introduce the subject matter for general applications but specifics are given for the failure prediction project. In addition, the first task that must be completed in the verification & validation procedure is to perform a credibility assessment to fully understand the requirements and limitations of the current computational simulation capability for the specific application intended use. The PIRT and PCMM are tools used at Sandia National Laboratories (SNL) to provide a consistent manner to perform such an assessment. Ideally, all stakeholders should be represented and contribute to perform an accurate credibility assessment. PIRTs and PCMMs are both described in brief detail below and the resulting assessments for an example project are given.

  12. Determination of Thermal Properties of Fresh Water and Sea Water Ice using Multiphysics Analysis

    Directory of Open Access Journals (Sweden)

    T Rashid

    2016-08-01

    Full Text Available This paper presents a methodology to determine the thermal conductivity of ice using multiphysics analysis. This methodology used a combination of both experimentation and numerical simulation. In the experimental work, an ice block is observed using an infrared camera. The results reveal the variation in temperature over the surface. These results are dependent on two primary heat transfer parameters, namely, conductivity of ice within the ice cuboid and overall heat transfer coefficient. In addition to these two parameters, the surrounding temperature also affects the observed temperature profile. In the numerical simulation, the same behaviour is simulated using multiphysics tools. In this work, the finite difference method is used to discretize the heat equation and is solved using an FTCS (Forward-Time Central-Space method in MATLAB® software. The inputs to the simulation are the thermal properties of ice. These parameters are varied to match with the experimental results, hence revealing the real-time thermal properties of ice and surroundings.

  13. Modelling transport phenomena in a multi-physics context

    Energy Technology Data Exchange (ETDEWEB)

    Marra, Francesco [Dipartimento di Ingegneria Chimica e Alimentare - Università degli studi di Salerno Via Ponte Don Melillo - 84084 Fisciano SA (Italy)

    2015-01-22

    Innovative heating research on cooking, pasteurization/sterilization, defrosting, thawing and drying, often focuses on areas which include the assessment of processing time, evaluation of heating uniformity, studying the impact on quality attributes of the final product as well as considering the energy efficiency of these heating processes. During the last twenty years, so-called electro-heating-processes (radio-frequency - RF, microwaves - MW and ohmic - OH) gained a wide interest in industrial food processing and many applications using the above mentioned technologies have been developed with the aim of reducing processing time, improving process efficiency and, in many cases, the heating uniformity. In the area of innovative heating, electro-heating accounts for a considerable portion of both the scientific literature and commercial applications, which can be subdivided into either direct electro-heating (as in the case of OH heating) where electrical current is applied directly to the food or indirect electro-heating (e.g. MW and RF heating) where the electrical energy is firstly converted to electromagnetic radiation which subsequently generates heat within a product. New software packages, which make easier solution of PDEs based mathematical models, and new computers, capable of larger RAM and more efficient CPU performances, allowed an increasing interest about modelling transport phenomena in systems and processes - as the ones encountered in food processing - that can be complex in terms of geometry, composition, boundary conditions but also - as in the case of electro-heating assisted applications - in terms of interaction with other physical phenomena such as displacement of electric or magnetic field. This paper deals with the description of approaches used in modelling transport phenomena in a multi-physics context such as RF, MW and OH assisted heating.

  14. Modelling transport phenomena in a multi-physics context

    Science.gov (United States)

    Marra, Francesco

    2015-01-01

    Innovative heating research on cooking, pasteurization/sterilization, defrosting, thawing and drying, often focuses on areas which include the assessment of processing time, evaluation of heating uniformity, studying the impact on quality attributes of the final product as well as considering the energy efficiency of these heating processes. During the last twenty years, so-called electro-heating-processes (radio-frequency - RF, microwaves - MW and ohmic - OH) gained a wide interest in industrial food processing and many applications using the above mentioned technologies have been developed with the aim of reducing processing time, improving process efficiency and, in many cases, the heating uniformity. In the area of innovative heating, electro-heating accounts for a considerable portion of both the scientific literature and commercial applications, which can be subdivided into either direct electro-heating (as in the case of OH heating) where electrical current is applied directly to the food or indirect electro-heating (e.g. MW and RF heating) where the electrical energy is firstly converted to electromagnetic radiation which subsequently generates heat within a product. New software packages, which make easier solution of PDEs based mathematical models, and new computers, capable of larger RAM and more efficient CPU performances, allowed an increasing interest about modelling transport phenomena in systems and processes - as the ones encountered in food processing - that can be complex in terms of geometry, composition, boundary conditions but also - as in the case of electro-heating assisted applications - in terms of interaction with other physical phenomena such as displacement of electric or magnetic field. This paper deals with the description of approaches used in modelling transport phenomena in a multi-physics context such as RF, MW and OH assisted heating.

  15. Simulating muscular thin films using thermal contraction capabilities in finite element analysis tools.

    Science.gov (United States)

    Webster, Victoria A; Nieto, Santiago G; Grosberg, Anna; Akkus, Ozan; Chiel, Hillel J; Quinn, Roger D

    2016-10-01

    In this study, new techniques for approximating the contractile properties of cells in biohybrid devices using Finite Element Analysis (FEA) have been investigated. Many current techniques for modeling biohybrid devices use individual cell forces to simulate the cellular contraction. However, such techniques result in long simulation runtimes. In this study we investigated the effect of the use of thermal contraction on simulation runtime. The thermal contraction model was significantly faster than models using individual cell forces, making it beneficial for rapidly designing or optimizing devices. Three techniques, Stoney׳s Approximation, a Modified Stoney׳s Approximation, and a Thermostat Model, were explored for calibrating thermal expansion/contraction parameters (TECPs) needed to simulate cellular contraction using thermal contraction. The TECP values were calibrated by using published data on the deflections of muscular thin films (MTFs). Using these techniques, TECP values that suitably approximate experimental deflections can be determined by using experimental data obtained from cardiomyocyte MTFs. Furthermore, a sensitivity analysis was performed in order to investigate the contribution of individual variables, such as elastic modulus and layer thickness, to the final calibrated TECP for each calibration technique. Additionally, the TECP values are applicable to other types of biohybrid devices. Two non-MTF models were simulated based on devices reported in the existing literature.

  16. Specification of the Advanced Burner Test Reactor Multi-Physics Coupling Demonstration Problem

    Energy Technology Data Exchange (ETDEWEB)

    Shemon, E. R. [Argonne National Lab. (ANL), Argonne, IL (United States); Grudzinski, J. J. [Argonne National Lab. (ANL), Argonne, IL (United States); Lee, C. H. [Argonne National Lab. (ANL), Argonne, IL (United States); Thomas, J. W. [Argonne National Lab. (ANL), Argonne, IL (United States); Yu, Y. Q. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-12-21

    This document specifies the multi-physics nuclear reactor demonstration problem using the SHARP software package developed by NEAMS. The SHARP toolset simulates the key coupled physics phenomena inside a nuclear reactor. The PROTEUS neutronics code models the neutron transport within the system, the Nek5000 computational fluid dynamics code models the fluid flow and heat transfer, and the DIABLO structural mechanics code models structural and mechanical deformation. The three codes are coupled to the MOAB mesh framework which allows feedback from neutronics, fluid mechanics, and mechanical deformation in a compatible format.

  17. Modelling organs, tissues, cells and devices using Matlab and Comsol multiphysics

    CERN Document Server

    Dokos, Socrates

    2017-01-01

    This book presents a theoretical and practical overview of computational modeling in bioengineering, focusing on a range of applications including electrical stimulation of neural and cardiac tissue, implantable drug delivery, cancer therapy, biomechanics, cardiovascular dynamics, as well as fluid-structure interaction for modelling of organs, tissues, cells and devices. It covers the basic principles of modeling and simulation with ordinary and partial differential equations using MATLAB and COMSOL Multiphysics numerical software. The target audience primarily comprises postgraduate students and researchers, but the book may also be beneficial for practitioners in the medical device industry.

  18. ALE3D: An Arbitrary Lagrangian-Eulerian Multi-Physics Code

    Energy Technology Data Exchange (ETDEWEB)

    Noble, Charles R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Anderson, Andrew T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Barton, Nathan R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bramwell, Jamie A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Capps, Arlie [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Chang, Michael H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Chou, Jin J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dawson, David M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Diana, Emily R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dunn, Timothy A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Faux, Douglas R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Fisher, Aaron C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Greene, Patrick T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Heinz, Ines [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kanarska, Yuliya [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Khairallah, Saad A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Liu, Benjamin T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Margraf, Jon D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Nichols, Albert L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Nourgaliev, Robert N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Puso, Michael A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reus, James F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Robinson, Peter B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Shestakov, Alek I. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Solberg, Jerome M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Taller, Daniel [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Tsuji, Paul H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); White, Christopher A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); White, Jeremy L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-05-23

    ALE3D is a multi-physics numerical simulation software tool utilizing arbitrary-Lagrangian- Eulerian (ALE) techniques. The code is written to address both two-dimensional (2D plane and axisymmetric) and three-dimensional (3D) physics and engineering problems using a hybrid finite element and finite volume formulation to model fluid and elastic-plastic response of materials on an unstructured grid. As shown in Figure 1, ALE3D is a single code that integrates many physical phenomena.

  19. The multiphysics analysis of the metallic bipolar plate by the electrochemical micro-machining fabrication process

    Science.gov (United States)

    Lee, Yu-Ming; Lee, Shuo-Jen; Lee, Chi-Yuan; Chang, Dar-Yuan

    In this study, the flow channels of a PEM fuel cell are fabricated by the EMM process. The parametric effects of the process are studied by both numerical simulation and experimental tests. For the numerical simulation, the multiphysics model, consisting of electrical field, convection, and diffusion phenomena is applied using COMSOL software. COMSOL software is used to predict the parametric effects of the channel fabrication accuracy such as pulse rate, pulse duty cycle, inter-electrode gap and electrolytic inflow velocity. The proper experimental parameters and the relationship between the parameters and the distribution of metal removal are established from the simulated results. The experimental fabrication tests showed that a shorter pulse rate and a higher pulse current improved the fabrication accuracy, and is consistent with the numerical simulation results. The proposed simulation model could be employed as a predictive tool to provide optimal parameters for better machining accuracy and process stability of the EMM process.

  20. Multiphysics modeling using COMSOL a first principles approach

    CERN Document Server

    Pryor, Roger W

    2011-01-01

    Multiphysics Modeling Using COMSOL rapidly introduces the senior level undergraduate, graduate or professional scientist or engineer to the art and science of computerized modeling for physical systems and devices. It offers a step-by-step modeling methodology through examples that are linked to the Fundamental Laws of Physics through a First Principles Analysis approach. The text explores a breadth of multiphysics models in coordinate systems that range from 1D to 3D and introduces the readers to the numerical analysis modeling techniques employed in the COMSOL Multiphysics software. After readers have built and run the examples, they will have a much firmer understanding of the concepts, skills, and benefits acquired from the use of computerized modeling techniques to solve their current technological problems and to explore new areas of application for their particular technological areas of interest.

  1. Capability of TMPA products to simulate streamflow in upper Yellow and Yangtze River basins on Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    Zhen-chun HAO; Kai TONG; Xiao-li LIU; Lei-lei ZHANG

    2014-01-01

    Due to the high elevation, complex terrain, severe weather, and inaccessibility, direct meteorological observations do not exist over large portions of the Tibetan Plateau, especially the western part of it. Satellite rainfall estimates have been very important sources for precipitation information, particularly in rain gauge-sparse regions. In this study, Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) products 3B42, RTV5V6, and RTV7 were evaluated for their applicability to the upper Yellow and Yangtze River basins on the Tibetan Plateau. Moreover, the capability of the TMPA products to simulate streamflow was also investigated using the Variable Infiltration Capacity (VIC) semi-distributed hydrological model. Results show that 3B42 performs better than RTV5V6 and RTV7, based on verification of the China Meteorological Administration (CMA) observational precipitation data. RTV5V6 can roughly capture the spatial precipitation pattern but overestimation exists throughout the entire study region. The anticipated improvements of RTV7 relative to RTV5V6 have not been realized in this study. Our results suggest that RTV7 significantly overestimates the precipitation over the two river basins, though it can capture the seasonal cycle features of precipitation. 3B42 shows the best performance in streamflow simulation of the abovementioned satellite products. Although involved in gauge adjustment at a monthly scale, 3B42 is capable of daily streamflow simulation. RTV5V6 and RTV7 have no capability to simulate streamflow in the upper Yellow and Yangtze River basins.

  2. Design and multiphysics analysis of a 176Â MHz continuous-wave radio-frequency quadrupole

    Science.gov (United States)

    Kutsaev, S. V.; Mustapha, B.; Ostroumov, P. N.; Barcikowski, A.; Schrage, D.; Rodnizki, J.; Berkovits, D.

    2014-07-01

    We have developed a new design for a 176 MHz cw radio-frequency quadrupole (RFQ) for the SARAF upgrade project. At this frequency, the proposed design is a conventional four-vane structure. The main design goals are to provide the highest possible shunt impedance while limiting the required rf power to about 120 kW for reliable cw operation, and the length to about 4 meters. If built as designed, the proposed RFQ will be the first four-vane cw RFQ built as a single cavity (no resonant coupling required) that does not require π-mode stabilizing loops or dipole rods. For this, we rely on very detailed 3D simulations of all aspects of the structure and the level of machining precision achieved on the recently developed ATLAS upgrade RFQ. A full 3D model of the structure including vane modulation was developed. The design was optimized using electromagnetic and multiphysics simulations. Following the choice of the vane type and geometry, the vane undercuts were optimized to produce a flat field along the structure. The final design has good mode separation and should not need dipole rods if built as designed, but their effect was studied in the case of manufacturing errors. The tuners were also designed and optimized to tune the main mode without affecting the field flatness. Following the electromagnetic (EM) design optimization, a multiphysics engineering analysis of the structure was performed. The multiphysics analysis is a coupled electromagnetic, thermal and mechanical analysis. The cooling channels, including their paths and sizes, were optimized based on the limiting temperature and deformation requirements. The frequency sensitivity to the RFQ body and vane cooling water temperatures was carefully studied in order to use it for frequency fine-tuning. Finally, an inductive rf power coupler design based on the ATLAS RFQ coupler was developed and simulated. The EM design optimization was performed using cst Microwave Studio and the results were verified using

  3. A High-Resolution Capability for Large-Eddy Simulation of Jet Flows

    Science.gov (United States)

    DeBonis, James R.

    2011-01-01

    A large-eddy simulation (LES) code that utilizes high-resolution numerical schemes is described and applied to a compressible jet flow. The code is written in a general manner such that the accuracy/resolution of the simulation can be selected by the user. Time discretization is performed using a family of low-dispersion Runge-Kutta schemes, selectable from first- to fourth-order. Spatial discretization is performed using central differencing schemes. Both standard schemes, second- to twelfth-order (3 to 13 point stencils) and Dispersion Relation Preserving schemes from 7 to 13 point stencils are available. The code is written in Fortran 90 and uses hybrid MPI/OpenMP parallelization. The code is applied to the simulation of a Mach 0.9 jet flow. Four-stage third-order Runge-Kutta time stepping and the 13 point DRP spatial discretization scheme of Bogey and Bailly are used. The high resolution numerics used allows for the use of relatively sparse grids. Three levels of grid resolution are examined, 3.5, 6.5, and 9.2 million points. Mean flow, first-order turbulent statistics and turbulent spectra are reported. Good agreement with experimental data for mean flow and first-order turbulent statistics is shown.

  4. Nuclear Reactor Simulations for Unveiling Diversion Scenarios: capabilities of the antineutrino probe

    Energy Technology Data Exchange (ETDEWEB)

    Bui, V.M.; Fallot, M.; Giot, L.; Guillon, B.; Martino, J.; Yermia, F. [SUBATECH - CNRS-IN2P3 - Univ. of Nantes - EMN, Nantes (France); Nuttin, A. [LPSC - CNRS-IN2P3/UJF/INPG, Grenoble (France)

    2009-06-15

    After many years of fundamental research, physicists have a good understanding of the neutrinos detection techniques. It is now possible to apply neutrino physics as a new tool to monitor nuclear power plants. We already know that modest size detectors are achievable to fulfill that task such as the SONGS 1 and the future Nucifer detectors. In parallel, sophisticated simulations of reactors and their associated antineutrino flux and energy spectrum have been developed to predict the neutrino signature of the fuel burnup and of a diversion. Taking advantage of the tremendous quantity of information available nowadays in nuclear databases, the total {beta} spectrum of a reactor is built by adding the contributions of all the {beta} branches involved in the decay of all fission products (FP). A package called MCNP Utility for Reactor Evolution (MURE) computes the fuel and FP inventories by simulating the neutronics and time evolution of a reactor core. MURE, initially developed by CNRS/IN2P3/LPSC Grenoble and IPN Orsay to study Generation IV reactors, is a precision code written in C++ which automates the preparation and computation of successive MCNP calculations either for precision burnup or thermal-hydraulics purpose. MURE will be soon available at NEA. The only user-defined inputs driving the time evolution of the isotopic composition of the core are the initial fuel composition, the refueling scheme, and the thermal power. The evolution of the antineutrino flux and energy spectrum with the fuel burnup, as well as the effect of neutron capture on various nuclei are taken into account. Nonproliferation scenarios and burnup monitoring with antineutrinos have been studied using these tools for PWR and Candu reactors. A full core simulation of an N4-PWR will be presented in a first part. Gross unveiling diversion scenarios using a PWR have been simulated in order to test the ability of the antineutrino probe. A channel of a Heavy Water Reactor (Candu 600) loaded with

  5. SM/MURF: Current Capabilities and Verification as a Replacement of AFRL Plume Simulation Tool COLISEUM

    Science.gov (United States)

    2016-07-27

    of Mathematical Statics, Vol. 29, No. 2, 1958, pp. 610–611. 8Bird, G. A., Molecular Gas Dynamics and the Direct Simulation of Gas Flows, Clarendon...and Manzella, D., “End-of-life Stationary Plasma Thruster far-field plume characterization,” 32nd Joint Propulsion Conference, Lake Buena Vista , Florida...17, No. 6, Nov 1990, pp. 3246–3254. [7] Pencil, E. J., Randolph, T., and Manzella, D., 32nd JPC, Lake Buena Vista , Florida, July 1996, pp. 1–28

  6. Evaluation of the capability of RegCM4.0 in simulating East African climate

    Science.gov (United States)

    Ogwang, Bob Alex; Chen, Haishan; Li, Xing; Gao, Chujie

    2016-04-01

    The International Centre for Theoretical Physics (ICTP) regional climate model RegCM4.0 is used in this study to examine its ability to reproduce the climate of East Africa (EA) in regard to the annual cycle and June-to-August (JJA) seasonal climatology. Two domain sizes [large domain (LD) and small domain (SD)] and two cumulus convection schemes [Grell convection scheme with Fritsch-Chappell closure assumption (GRE scheme) and MIT scheme (EMA scheme)] are used. Simulations were done for the period 1989-2008 at a resolution of 50 km. The experiments were performed with the initial and lateral boundary conditions obtained from ERA-Interim-gridded reanalysis data at a 1.5° resolution. The variables investigated are precipitation, temperature, humidity, diurnal temperature range, and 850-hPa winds. Results show that the model realistically reproduces the East African climate, with a few discrepancies due to the different cumulus convection schemes and the domain sizes used. Grell with Fritsch-Chappell (Grell-FC) scheme captures well the observed climate in regard to the annual cycle and June-to-August seasonal climatology, with a tendency to underestimate rainfall over the JJA rainfall maximum region (RMR). This scheme performs better in LD than in SD. EMA scheme similarly captures well the observed climatology. It tends to overestimate rainfall over RMR. It however performs better in SD than in LD. The ensemble mean of simulations with GRE and EMA schemes (ENSM) tends to offer an improved representation of the observed climate, with a few discrepancies owing to the individual schemes used. In general, therefore, considering the performance of the model in both domains, the East African climate based on this study is better simulated by the Grell-FC scheme over LD. The observed biases in this study signify that the ability of the model in simulating climate over East Africa is still a significant challenge. Thus, future work must focus on improving the performance of

  7. Expand the Modeling Capabilities of DOE's EnergyPlus Building Energy Simulation Program

    Energy Technology Data Exchange (ETDEWEB)

    Don Shirey

    2008-02-28

    EnergyPlus{trademark} 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. Version 1.0 of EnergyPlus was released in April 2001, followed by semiannual updated versions over the ensuing seven-year period. This report summarizes work performed by the University of Central Florida's Florida Solar Energy Center (UCF/FSEC) to expand the modeling capabilities of EnergyPlus. The project tasks involved implementing, testing, and documenting the following new features or enhancement of existing features: (1) A model for packaged terminal heat pumps; (2) A model for gas engine-driven heat pumps with waste heat recovery; (3) Proper modeling of window screens; (4) Integrating and streamlining EnergyPlus air flow modeling capabilities; (5) Comfort-based controls for cooling and heating systems; and (6) An improved model for microturbine power generation with heat recovery. UCF/FSEC located existing mathematical models or generated new model for these features and incorporated them into EnergyPlus. The existing or new models were (re)written using Fortran 90/95 programming language and were integrated within EnergyPlus in accordance with the EnergyPlus Programming Standard and Module Developer's Guide. Each model/feature was thoroughly tested and identified errors were repaired. Upon completion of each model implementation, the existing EnergyPlus documentation (e.g., Input Output Reference and Engineering Document) was updated with information describing the new or enhanced feature. Reference data sets were generated for several of the features to aid program users in selecting proper

  8. The GEANT4 toolkit capability in the hadron therapy field: simulation of a transport beam line

    Science.gov (United States)

    Cirrone, G. A. P.; Cuttone, G.; Di Rosa, F.; Raffaele, L.; Russo, G.; Guatelli, S.; Pia, M. G.

    2006-01-01

    At Laboratori Nazionali del Sud of the Instituto Nazionale di Fisica Nucleare of Catania (Sicily, Italy), the first Italian hadron therapy facility named CATANA (Centro di AdroTerapia ed Applicazioni Nucleari Avanzate) has been realized. Inside CATANA 62 MeV proton beams, accelerated by a superconducting cyclotron, are used for the radiotherapeutic treatments of some types of ocular tumours. Therapy with hadron beams still represents a pioneer technique, and only a few centers worldwide can provide this advanced specialized cancer treatment. On the basis of the experience so far gained, and considering the future hadron-therapy facilities to be developed (Rinecker, Munich Germany, Heidelberg/GSI, Darmstadt, Germany, PSI Villigen, Switzerland, CNAO, Pavia, Italy, Centro di Adroterapia, Catania, Italy) we decided to develop a Monte Carlo application based on the GEANT4 toolkit, for the design, the realization and the optimization of a proton-therapy beam line. Another feature of our project is to provide a general tool able to study the interactions of hadrons with the human tissue and to test the analytical-based treatment planning systems actually used in the routine practice. All the typical elements of a hadron-therapy line, such as diffusers, range shifters, collimators and detectors were modelled. In particular, we simulated the Markus type ionization chamber and a Gaf Chromic film as dosimeters to reconstruct the depth (Bragg peak and Spread Out Bragg Peak) and lateral dose distributions, respectively. We validated our simulated detectors comparing the results with the experimental data available in our facility.

  9. EXPANDING THE CAPABILITIES OF DOE'S ENERGYPLUS BUILDING ENERGY SIMULATION PROGRAM

    Energy Technology Data Exchange (ETDEWEB)

    Don B. Shirey, III; Richard A. Raustad

    2004-04-01

    EnergyPlus{trademark} is a new generation analysis tool that is being 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 will also support evaluation and decision making of zero energy building (ZEB) energy efficiency and supply technologies during new building design and existing building retrofits. Version 1.0 of EnergyPlus was released in April 2001, followed by six updated versions over the ensuing three-year period. This report summarizes work performed by the University of Central Florida's Florida Solar Energy Center (UCF/FSEC) to expand the capabilities of EnergyPlus. The project tasks involved implementing, testing, and documenting the following new features: (1) A model for energy recovery ventilation equipment that transfers both sensible (temperature) and latent (moisture) energy between building exhaust air and incoming outdoor ventilation air; (2) A model to account for the degradation of cooling coil dehumidification performance at part-load conditions; (3) A model for cooling coils augmented with air-to-air heat exchangers for improved dehumidification; and (4) A heat transfer coefficient calculator and automatic sizing algorithms for the existing EnergyPlus cooling tower model. UCF/FSEC located existing mathematical models for these features and incorporated them into EnergyPlus. The software models were written using Fortran-90 and were integrated within EnergyPlus in accordance with the EnergyPlus Programming Standard and Module Developer's Guide. Each model/feature was thoroughly tested and identified errors were repaired. Upon completion of each model implementation, the existing EnergyPlus documentation (Input Output Reference and Engineering Document) was updated with information describing the new model/feature.

  10. The simulation of multiphase flow field in implantable blood pump and analysis of hemolytic capability

    Institute of Scientific and Technical Information of China (English)

    LI Tie-yan; YE Liang; HONG Fang-wen; LIU Deng-cheng; FAN Hui-min; LIU Zhong-min

    2013-01-01

    The numerical simulation of the axial flow impeller blood pump NIVADIII is carried out by using a CFD multiphase flow model.The hydrodynamic performance of the pump and the flow field in the pump are analyzed,and the shear stress distribution is obtained.A hemolytic prediction model based on the shear stress is built based on the calculation results,and it can be used for quantitative predictions of the hemolytic behavior of a blood pump.Hemolysis tests in vitro were performed 6 times with fresh bovine blood.At each time,the flow of the pump NIVADIII is 5 L/min and the outflow tract pressure is 100 mmHg.According to the tests,the plasma free hemoglobin (FHB) content and the hematocrit (HCT) are measured after 0 s,0.5 s,1 s,1.5 s,...4 s.At the end of each experiment Normal Index of Hemolysis (NIH) of NIVADIII is calculated.The average of NIH is 0.0055 g/100L,almost identical with that obtained from the hemolytic prediction model.This method can be applied in the selection stage of a blood pump.

  11. Numerical simulation of armor capability of AI2O3 and SiC armor tiles

    Science.gov (United States)

    Rashid, T.; Aleem, M. A.; Akbar, S.; Rauf, A.; Shuaib, M.

    2016-08-01

    Alumina and Silicon Carbide armor plates have been tested numerically against 7.62x51 (mm x mm) armor piercing (AP) projectiles. A 2-D problem with axial symmetry has been designedand the simulations were carried out using commercial software ANSYS AUTODYN. Experiments were modeled for Alumina (99.5%), Alumina (99.7%) and SiC with a range of tile thicknesses (5, 10, 15 and 20 mm). The projectile was chosen as 7.62 x 51AP bullet (initial velocity 810 m/sec)with two different core materials Steel 4340 and WC, however, casing material was copper for both cores. SiC showed better defense against AP bullet as compared to Al2O3. The residual velocity and momentum of the bullet were found to decrease with increasing tile thickness. SiC tiles with thickness 15mm and 20 mm successfully sustained penetration against steel 4340 and WC core bullets, respectively. However none of the Alumina targets succeeded in stopping the bullet.

  12. Flexural Capability of Patterned Transparent Conductive Substrate by Performing Electrical Measurements and Stress Simulations

    Directory of Open Access Journals (Sweden)

    Chang-Chun Lee

    2016-10-01

    Full Text Available The suitability of stacked thin films for next-generation display technology was analyzed based on their properties and geometrical designs to evaluate the mechanical reliability of transparent conducting thin films utilized in flexural displays. In general, the high bending stress induced by various operation conditions is a major concern regarding the mechanical reliability of indium–tin–oxide (ITO films deposited on polyethylene terephthalate (PET substrates; mechanical reliability is commonly used to estimate the flexibility of displays. However, the pattern effect is rarely investigated to estimate the mechanical reliability of ITO/PET films. Thus, this study examined the flexible content of patterned ITO/PET films with two different line widths by conducting bending tests and sheet resistance measurements. Moreover, a stress–strain simulation enabled by finite element analysis was performed on the patterned ITO/PET to explore the stress impact of stacked film structures under various levels of flexural load. Results show that the design of the ITO/PET film can be applied in developing mechanically reliable flexible electronics.

  13. 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.

  14. CHRONO: a parallel multi-physics library for rigid-body, flexible-body, and fluid dynamics

    Directory of Open Access Journals (Sweden)

    H. Mazhar

    2013-02-01

    Full Text Available The last decade witnessed a manifest shift in the microprocessor industry towards chip designs that promote parallel computing. Until recently the privilege of a select group of large research centers, Teraflop computing is becoming a commodity owing to inexpensive GPU cards and multi to many-core x86 processors. This paradigm shift towards large scale parallel computing has been leveraged in CHRONO, a freely available C++ multi-physics simulation package. CHRONO is made up of a collection of loosely coupled components that facilitate different aspects of multi-physics modeling, simulation, and visualization. This contribution provides an overview of CHRONO::Engine, CHRONO::Flex, CHRONO::Fluid, and CHRONO::Render, which are modules that can capitalize on the processing power of hundreds of parallel processors. Problems that can be tackled in CHRONO include but are not limited to granular material dynamics, tangled large flexible structures with self contact, particulate flows, and tracked vehicle mobility. The paper presents an overview of each of these modules and illustrates through several examples the potential of this multi-physics library.

  15. Computational Challenges in Nuclear Weapons Simulation

    Energy Technology Data Exchange (ETDEWEB)

    McMillain, C F; Adams, T F; McCoy, M G; Christensen, R B; Pudliner, B S; Zika, M R; Brantley, P S; Vetter, J S; May, J M

    2003-08-29

    After a decade of experience, the Stockpile Stewardship Program continues to ensure the safety, security and reliability of the nation's nuclear weapons. The Advanced Simulation and Computing (ASCI) program was established to provide leading edge, high-end simulation capabilities needed to meet the program's assessment and certification requirements. The great challenge of this program lies in developing the tools and resources necessary for the complex, highly coupled, multi-physics calculations required to simulate nuclear weapons. This paper describes the hardware and software environment we have applied to fulfill our nuclear weapons responsibilities. It also presents the characteristics of our algorithms and codes, especially as they relate to supercomputing resource capabilities and requirements. It then addresses impediments to the development and application of nuclear weapon simulation software and hardware and concludes with a summary of observations and recommendations on an approach for working with industry and government agencies to address these impediments.

  16. Case studies on optimization problems in MATLAB and COMSOL multiphysics by means of the livelink

    Science.gov (United States)

    Ozana, Stepan; Pies, Martin; Docekal, Tomas

    2016-06-01

    LiveLink for COMSOL is a tool that integrates COMSOL Multiphysics with MATLAB to extend one's modeling with scripting programming in the MATLAB environment. It allows user to utilize the full power of MATLAB and its toolboxes in preprocessing, model manipulation, and post processing. At first, the head script launches COMSOL with MATLAB and defines initial value of all parameters, refers to the objective function J described in the objective function and creates and runs the defined optimization task. Once the task is launches, the COMSOL model is being called in the iteration loop (from MATLAB environment by use of API interface), changing defined optimization parameters so that the objective function is minimized, using fmincon function to find a local or global minimum of constrained linear or nonlinear multivariable function. Once the minimum is found, it returns exit flag, terminates optimization and returns the optimized values of the parameters. The cooperation with MATLAB via LiveLink enhances a powerful computational environment with complex multiphysics simulations. The paper will introduce using of the LiveLink for COMSOL for chosen case studies in the field of technical cybernetics and bioengineering.

  17. Advances in High-Fidelity Multi-Physics Simulation Techniques

    Science.gov (United States)

    2008-01-01

    vibrational bias, it is useful to define an effective dissociation rate, kdeff [T, Tv], where: kdeff [T, Tv]Ntot ≡ v∗ ∑ v=0 kdvnv (56) and kdv is the...v∗ ∑ v=0 kdv nveq Ntot = v∗ ∑ v=0 kdv exp[−ǫv/kT ] Zvib[T ] (58) For the Ladder model, kdeff [T, Tv] = kdv ∗ nv∗ Ntot = kdeq [T ] nv∗ nveq = kdeq [T...exp[ǫv( 1 T − 1 Tv )] Zvib[T ] Zvib[Tv] (59) A simple weak bias model may be constructed by assuming: kdv = k0[T ] exp[−(D − ǫv)/T ] (60) where, the

  18. Predictive capability of average Stokes polarimetry for simulation of phase multilevel elements onto LCoS devices.

    Science.gov (United States)

    Martínez, Francisco J; Márquez, Andrés; Gallego, Sergi; Ortuño, Manuel; Francés, Jorge; Pascual, Inmaculada; Beléndez, Augusto

    2015-02-20

    Parallel-aligned (PA) liquid-crystal on silicon (LCoS) microdisplays are especially appealing in a wide range of spatial light modulation applications since they enable phase-only operation. Recently we proposed a novel polarimetric method, based on Stokes polarimetry, enabling the characterization of their linear retardance and the magnitude of their associated phase fluctuations or flicker, exhibited by many LCoS devices. In this work we apply the calibrated values obtained with this technique to show their capability to predict the performance of spatially varying phase multilevel elements displayed onto the PA-LCoS device. Specifically we address a series of multilevel phase blazed gratings. We analyze both their average diffraction efficiency ("static" analysis) and its associated time fluctuation ("dynamic" analysis). Two different electrical configuration files with different degrees of flicker are applied in order to evaluate the actual influence of flicker on the expected performance of the diffractive optical elements addressed. We obtain a good agreement between simulation and experiment, thus demonstrating the predictive capability of the calibration provided by the average Stokes polarimetric technique. Additionally, it is obtained that for electrical configurations with less than 30° amplitude for the flicker retardance, they may not influence the performance of the blazed gratings. In general, we demonstrate that the influence of flicker greatly diminishes when the number of quantization levels in the optical element increases.

  19. Multiphysics Model of Palladium Hydride Isotope Exchange Accounting for Higher Dimensionality

    Energy Technology Data Exchange (ETDEWEB)

    Gharagozloo, Patricia E.; Eliassi, Mehdi; Bon, Bradley Luis

    2015-03-01

    This report summarizes computational model developm ent and simulations results for a series of isotope exchange dynamics experiments i ncluding long and thin isothermal beds similar to the Foltz and Melius beds and a lar ger non-isothermal experiment on the NENG7 test bed. The multiphysics 2D axi-symmetr ic model simulates the temperature and pressure dependent exchange reactio n kinetics, pressure and isotope dependent stoichiometry, heat generation from the r eaction, reacting gas flow through porous media, and non-uniformities in the bed perme ability. The new model is now able to replicate the curved reaction front and asy mmetry of the exit gas mass fractions over time. The improved understanding of the exchange process and its dependence on the non-uniform bed properties and te mperatures in these larger systems is critical to the future design of such sy stems.

  20. Two-Step Multi-Physics Analysis of an Annular Linear Induction Pump for Fission Power Systems

    Science.gov (United States)

    Geng, Steven M.; Reid, Terry V.

    2016-01-01

    One of the key technologies associated with fission power systems (FPS) is the annular linear induction pump (ALIP). ALIPs are used to circulate liquid-metal fluid for transporting thermal energy from the nuclear reactor to the power conversion device. ALIPs designed and built to date for FPS project applications have not performed up to expectations. A unique, two-step approach was taken toward the multi-physics examination of an ALIP using ANSYS Maxwell 3D and Fluent. This multi-physics approach was developed so that engineers could investigate design variations that might improve pump performance. Of interest was to determine if simple geometric modifications could be made to the ALIP components with the goal of increasing the Lorentz forces acting on the liquid-metal fluid, which in turn would increase pumping capacity. The multi-physics model first calculates the Lorentz forces acting on the liquid metal fluid in the ALIP annulus. These forces are then used in a computational fluid dynamics simulation as (a) internal boundary conditions and (b) source functions in the momentum equations within the Navier-Stokes equations. The end result of the two-step analysis is a predicted pump pressure rise that can be compared with experimental data.

  1. Simulations of the X-ray imaging capabilities of the Silicon Drift Detectors (SDD) for the LOFT Wide Field Monitor

    CERN Document Server

    Evangelista, Y; Del Monte, E; Donnarumma, I; Feroci, M; Muleri, F; Pacciani, L; Soffitta, P; Rachevski, A; Vacchi, A; Zampa, G; Zampa, N; Suchy, S; Brandt, S; Budtz-Jørgensen, C; Hernanz, M

    2012-01-01

    The Large Observatory For X-ray Timing (LOFT), selected by ESA as one of the four Cosmic Vision M3 candidate missions to undergo an assessment phase, will revolutionize the study of compact objects in our galaxy and of the brightest supermassive black holes in active galactic nuclei. The Large Area Detector (LAD), carrying an unprecedented effective area of 10 m^2, is complemented by a coded-mask Wide Field Monitor, in charge of monitoring a large fraction of the sky potentially accessible to the LAD, to provide the history and context for the sources observed by LAD and to trigger its observations on their most interesting and extreme states. In this paper we present detailed simulations of the imaging capabilities of the Silicon Drift Detectors developed for the LOFT Wide Field Monitor detection plane. The simulations explore a large parameter space for both the detector design and the environmental conditions, allowing us to optimize the detector characteristics and demonstrating the X-ray imaging performa...

  2. KIT multi-physics tools for the analysis of design and beyond design basis accidents of light water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, Victor Hugo; Miassoedov, Alexei; Steinbrueck, M.; Tromm, W. [Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (Germany)

    2016-05-15

    This paper describes the KIT numerical simulation tools under extension and validation for the analysis of design and beyond design basis accidents (DBA) of Light Water Reactors (LWR). The description of the complex thermal hydraulic, neutron kinetics and chemo-physical phenomena going on during off-normal conditions requires the development of multi-physics and multi-scale simulations tools which are fostered by the rapid increase in computer power nowadays. The KIT numerical tools for DBA and beyond DBA are validated using experimental data of KIT or from abroad. The developments, extensions, coupling approaches and validation work performed at KIT are shortly outlined and discussed in this paper.

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

    Energy Technology Data Exchange (ETDEWEB)

    Turinsky, Paul J., E-mail: turinsky@ncsu.edu [North Carolina State University, PO Box 7926, Raleigh, NC 27695-7926 (United States); Kothe, Douglas B., E-mail: kothe@ornl.gov [Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6164 (United States)

    2016-05-15

    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

  4. Multi-Physics Markov Chain Monte Carlo Methods for Subsurface Flows

    Science.gov (United States)

    Rigelo, J.; Ginting, V.; Rahunanthan, A.; Pereira, F.

    2014-12-01

    For CO2 sequestration in deep saline aquifers, contaminant transport in subsurface, and oil or gas recovery, we often need to forecast flow patterns. Subsurface characterization is a critical and challenging step in flow forecasting. To characterize subsurface properties we establish a statistical description of the subsurface properties that are conditioned to existing dynamic and static data. A Markov Chain Monte Carlo (MCMC) algorithm is used in a Bayesian statistical description to reconstruct the spatial distribution of rock permeability and porosity. The MCMC algorithm requires repeatedly solving a set of nonlinear partial differential equations describing displacement of fluids in porous media for different values of permeability and porosity. The time needed for the generation of a reliable MCMC chain using the algorithm can be too long to be practical for flow forecasting. In this work we develop fast and effective computational methods for generating MCMC chains in the Bayesian framework for the subsurface characterization. Our strategy consists of constructing a family of computationally inexpensive preconditioners based on simpler physics as well as on surrogate models such that the number of fine-grid simulations is drastically reduced in the generated MCMC chains. In particular, we introduce a huff-puff technique as screening step in a three-stage multi-physics MCMC algorithm to reduce the number of expensive final stage simulations. The huff-puff technique in the algorithm enables a better characterization of subsurface near wells. We assess the quality of the proposed multi-physics MCMC methods by considering Monte Carlo simulations for forecasting oil production in an oil reservoir.

  5. Multiphysics phase field modeling of hydrogen diffusion and delta-hydride precipitation in alpha-zirconium

    Science.gov (United States)

    Jokisaari, Andrea M.

    Hydride precipitation in zirconium is a significant factor limiting the lifetime of nuclear fuel cladding, because hydride microstructures play a key role in the degradation of fuel cladding. However, the behavior of hydrogen in zirconium has typically been modeled using mean field approaches, which do not consider microstructural evolution. This thesis describes a quantitative microstructural evolution model for the alpha-zirconium/delta-hydride system and the associated numerical methods and algorithms that were developed. The multiphysics, phase field-based model incorporates CALPHAD free energy descriptions, linear elastic solid mechanics, and classical nucleation theory. A flexible simulation software implementing the model, Hyrax, is built on the Multiphysics Object Oriented Simulation Environment (MOOSE) finite element framework. Hyrax is open-source and freely available; moreover, the numerical methods and algorithms that have been developed are generalizable to other systems. The algorithms are described in detail, and verification studies for each are discussed. In addition, analyses of the sensitivity of the simulation results to the choice of numerical parameters are presented. For example, threshold values for the CALPHAD free energy algorithm and the use of mesh and time adaptivity when employing the nucleation algorithm are studied. Furthermore, preliminary insights into the nucleation behavior of delta-hydrides are described. These include a) the sensitivities of the nucleation rate to temperature, interfacial energy, composition and elastic energy, b) the spatial variation of the nucleation rate around a single precipitate, and c) the effect of interfacial energy and nucleation rate on the precipitate microstructure. Finally, several avenues for future work are discussed. Topics encompass the terminal solid solubility hysteresis of hydrogen in zirconium and the effects of the alpha/delta interfacial energy, as well as thermodiffusion, plasticity

  6. Screening for lactic acid bacteria capable of inhibiting Campylobacter jejuni in in vitro simulations of the broiler chicken caecal environment.

    Science.gov (United States)

    Robyn, J; Rasschaert, G; Messens, W; Pasmans, F; Heyndrickx, M

    2012-12-01

    Thermotolerant Campylobacter spp., specifically Campylobacter jejuni and Campylobacter coli, are the most common bacterial causes of human gastroenteritis in developed countries. Consumption of improperly prepared poultry products and cross contamination are among the main causes of human campylobacteriosis. The aim of this study was to identify lactic acid bacterial (LAB) strains capable of inhibiting C. jejuni growth in initial in vitro trials ('spot-on-lawn' method), as well as in batch fermentation studies mimicking the broiler caecal environment. These experiments served as an indication for using these strains to decrease the capability of Campylobacter to colonise and grow in the chicken caeca during primary production, with the aim of reducing the number of human campylobacteriosis cases. A total of 1,150 LAB strains were screened for anti-Campylobacter activity. Six strains were selected: members of the species Lactobacillus reuteri, Lactobacillus agilis, Lactobacillus helveticus, Lactobacillus salivarius, Enterococcus faecalis and Enterococcus faecium. After treatment with catalase, proteinase K and a-chymotrypsin, anti-Campylobacter activity of cell-free culture supernatant fluid (CSF) for all six strains was retained, which indicated that activity was probably not exerted by bacteriocin production. Based on the activity found in CSF, the compounds produced by the selected strains are secreted and do not require presence of live bacterial producer cells for activity. During initial in vitro fermentation experiments, the E. faecalis strain exhibited the highest inhibitory activity for C. jejuni and was selected for further fermentation experiments. In these experiments we tested for therapeutic or protective effects of the E. faecalis strain against C. jejuni MB 4185 infection under simulated broiler caecal growth conditions. The best inhibition results were obtained when E. faecalis was inoculated before the C. jejuni strain, lowering C. jejuni counts at

  7. Mathematical and algorithmic issues in multiphysics coupling.

    Energy Technology Data Exchange (ETDEWEB)

    Gai, Xiuli (University of Texas at Austin, Austin, TX); Stone, Charles Michael; Wheeler, Mary Fanett (University of Texas at Austin, Austin, TX)

    2004-06-01

    The modeling of fluid/structure interaction is of growing importance in both energy and environmental applications. Because of the inherent complexity, these problems must be simulated on parallel machines in order to achieve high resolution. The purpose of this research was to investigate techniques for coupling flow and geomechanics in porous media that are suitable for parallel computation. In particular, our main objective was to develop an iterative technique which can be as accurate as a fully coupled model but which allows for robust and efficient coupling of existing complex models (software). A parallel linear elastic module was developed which was coupled to a three phase three-component black oil model in IPARS (Integrated Parallel Accurate Reservoir Simulator). An iterative de-coupling technique was introduced at each time step. The resulting nonlinear iteration involved solving for displacements and flow sequentially. Rock compressibility was used in the flow model to account for the effect of deformation on the pore volume. Convergence was achieved when the mass balance for each component satisfied a given tolerance. This approach was validated by comparison with a fully coupled approach implemented in the British PetroledAmoco ACRES simulator. Another objective of this work was to develop an efficient parallel solver for the elasticity equations. A preconditioned conjugate gradient solver was implemented to solve the algebraic system arising from tensor product linear Galerkin approximations for the displacements. Three preconditioners were developed: LSOR (line successive over-relaxation), block Jacobi, and agglomeration multi-grid. The latter approach involved coarsening the 3D system to 2D and using LSOR as a smoother that is followed by applying geometric multi-grid with SOR (successive over-relaxation) as a smoother. Preliminary tests on a 64-node Beowulf cluster at CSM indicate that the agglomeration multi-grid approach is robust and efficient.

  8. Mathematical and algorithmic issues in multiphysics coupling.

    Energy Technology Data Exchange (ETDEWEB)

    Gai, Xiuli (University of Texas at Austin, Austin, TX); Stone, Charles Michael; Wheeler, Mary Fanett (University of Texas at Austin, Austin, TX)

    2004-06-01

    The modeling of fluid/structure interaction is of growing importance in both energy and environmental applications. Because of the inherent complexity, these problems must be simulated on parallel machines in order to achieve high resolution. The purpose of this research was to investigate techniques for coupling flow and geomechanics in porous media that are suitable for parallel computation. In particular, our main objective was to develop an iterative technique which can be as accurate as a fully coupled model but which allows for robust and efficient coupling of existing complex models (software). A parallel linear elastic module was developed which was coupled to a three phase three-component black oil model in IPARS (Integrated Parallel Accurate Reservoir Simulator). An iterative de-coupling technique was introduced at each time step. The resulting nonlinear iteration involved solving for displacements and flow sequentially. Rock compressibility was used in the flow model to account for the effect of deformation on the pore volume. Convergence was achieved when the mass balance for each component satisfied a given tolerance. This approach was validated by comparison with a fully coupled approach implemented in the British PetroledAmoco ACRES simulator. Another objective of this work was to develop an efficient parallel solver for the elasticity equations. A preconditioned conjugate gradient solver was implemented to solve the algebraic system arising from tensor product linear Galerkin approximations for the displacements. Three preconditioners were developed: LSOR (line successive over-relaxation), block Jacobi, and agglomeration multi-grid. The latter approach involved coarsening the 3D system to 2D and using LSOR as a smoother that is followed by applying geometric multi-grid with SOR (successive over-relaxation) as a smoother. Preliminary tests on a 64-node Beowulf cluster at CSM indicate that the agglomeration multi-grid approach is robust and efficient.

  9. Identification of Native Bacteria of the Candelaria and Tatacoa Semiarid Zone, Capable of Withstanding a Mars UV Radiation Simulation

    Science.gov (United States)

    Mendez, Y.; Vives, M.

    2017-07-01

    This work is the first study to describe native bacteria from the semi-arid areas in Candelaria and Tatacoa in Colombia, able to withstand a simulation of UV radiation, in order to draw an analogy with microbial growth on the surface of Mars. Sampling was carried out in the areas mentioned taking 50 samples of sediment divided into 25 samples of surface and 25 deep samples. As soon as the samples were transferred, they were subjected to a test of UV radiation in an atmospheric simulation chamber designed for the experiment, for periods of 1, 6 and 12 hours of exposure. Microbiological analysis as a method of plate dilution and isolation were performed using the modified AIS growth medium, macroscopic and microscopic description of morphotypes, biochemical identification of the morphotypes found, extraction of the feasible mycelium, DNA extraction and amplification of the gene 16 S by PCR. 13 morphotypes of bacteria resistant to UV radiation were found, mostly compatible with the gender of Streptomyces. One of the morphotypes found resisted 12 hours exposure. Molecular analyzes did not produce any results, because it was not possible to amplify the 16S by PCR, this may be due to that the exposure to UV radiation can degrade the DNA in existence, a affecting the results. The finding of native bacteria capable of withstanding conditions UV radiation can give us an approximation of microbial growth, mechanisms of resistance and survival under extreme conditions such as those found on Mars, in order to develop biotechnological applications and establish planetary analogues to understand the origin and evolution of the universe.

  10. Modelling of gastrocnemius muscle using Hills equation in COMSOL Multiphysics 4.0a

    Directory of Open Access Journals (Sweden)

    S.Vivekanandan

    2012-05-01

    Full Text Available This paper summarizes the force generated by gastrocnemius muscle for the analysis of muscoskeletal simulation in human locomotion using Hills muscle model. Biomechanics of Hills equation describes the study of physical phenomenon by means of mathematical model that relates force and muscle length with the help of a partial differential equation. To calculate maximum fatigue in the muscle and to discriminate strained muscle from the normal one FEM based modelling was done in COMSOL Multiphysics 4.0a. The model parameters were evaluated using similar in vitro experiments performed on frogs gastrocnemius muscle. The biomechanical model was then incorporated into human body for the purpose of predicting force - length response for all the four phases of gait cycle. Evaluating the response for gait cycle will enable the physiotherapist to obtain clues for muscle weakness and fatigue in a rehabilitation program

  11. Multiscale Multiphysics-Based Modeling and Analysis on the Tool Wear in Micro Drilling

    Science.gov (United States)

    Niu, Zhichao; Cheng, Kai

    2016-02-01

    In micro-cutting processes, process variables including cutting force, cutting temperature and drill-workpiece interfacing conditions (lubrication and interaction, etc.) significantly affect the tool wear in a dynamic interactive in-process manner. The resultant tool life and cutting performance directly affect the component surface roughness, material removal rate and form accuracy control, etc. In this paper, a multiscale multiphysics oriented approach to modeling and analysis is presented particularly on tooling performance in micro drilling processes. The process optimization is also taken account based on establishing the intrinsic relationship between process parameters and cutting performance. The modeling and analysis are evaluated and validated through well-designed machining trials, and further supported by metrology measurements and simulations. The paper is concluded with a further discussion on the potential and application of the approach for broad micro manufacturing purposes.

  12. Module-based Hybrid Uncertainty Quantification for Multi-physics Applications: Theory and Software

    Energy Technology Data Exchange (ETDEWEB)

    Tong, Charles [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Chen, Xiao [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Iaccarino, Gianluca [Stanford Univ., CA (United States); Mittal, Akshay [Stanford Univ., CA (United States)

    2013-10-08

    In this project we proposed to develop an innovative uncertainty quantification methodology that captures the best of the two competing approaches in UQ, namely, intrusive and non-intrusive approaches. The idea is to develop the mathematics and the associated computational framework and algorithms to facilitate the use of intrusive or non-intrusive UQ methods in different modules of a multi-physics multi-module simulation model in a way that physics code developers for different modules are shielded (as much as possible) from the chores of accounting for the uncertain ties introduced by the other modules. As the result of our research and development, we have produced a number of publications, conference presentations, and a software product.

  13. Assessing reactor physics codes capabilities to simulate fast reactors on the example of the BN-600 benchmark

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Vladimir [Scientific and Engineering Centre for Nuclear and Radiation Safety (SES NRS), Moscow (Russian Federation); Bousquet, Jeremy [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH, Garching (Germany)

    2016-11-15

    This work aims to assess the capabilities of reactor physics codes (initially validated for thermal reactors) to simulate fast sodium cooled reactors. The BFS-62-3A critical experiment from the BN-600 Hybrid Core Benchmark Analyses was chosen for the investigation. Monte-Carlo codes (KENO from SCALE and SERPENT 2.1.23) and the deterministic diffusion code DYN3D-MG are applied to calculate the neutronic parameters. It was found that the multiplication factor and reactivity effects calculated by KENO and SERPENT using the ENDF/B-VII.0 continuous energy library are in a good agreement with each other and with the measured benchmark values. Few-groups macroscopic cross sections, required for DYN3D-MG, were prepared in applying different methods implemented in SCALE and SERPENT. The DYN3D-MG results of a simplified benchmark show reasonable agreement with results from Monte-Carlo calculations and measured values. The former results are used to justify DYN3D-MG implementation for sodium cooled fast reactors coupled deterministic analysis.

  14. DEMONSTRATION OF LEACHXS/ORCHESTRA CAPABILITIES BY SIMULATING CONSTITUENT RELEASE FROM A CEMENTITIOUS WASTE FORM IN A REINFORCED CONCRETE VAULT

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C.; Meeussen, J.; Sloot, H.

    2010-03-31

    The objective of the work described in this report is to demonstrate the capabilities of the current version of LeachXS{trademark}/ORCHESTRA for simulating chemical behavior and constituent release processes in a range of applications that are relevant to the CBP. This report illustrates the use of LeachXS{trademark}/ORCHESTRA for the following applications: (1) Comparing model and experimental results for leaching tests for a range of cementitious materials including cement mortars, grout, stabilized waste, and concrete. The leaching test data includes liquid-solid partitioning as a function of pH and release rates based on laboratory column, monolith, and field testing. (2) Modeling chemical speciation of constituents in cementitious materials, including liquid-solid partitioning and release rates. (3) Evaluating uncertainty in model predictions based on uncertainty in underlying composition, thermodynamic, and transport characteristics. (4) Generating predominance diagrams to evaluate predicted chemical changes as a result of material aging using the example of exposure to atmospheric conditions. (5) Modeling coupled geochemical speciation and diffusion in a three layer system consisting of a layer of Saltstone, a concrete barrier, and a layer of soil in contact with air. The simulations show developing concentration fronts over a time period of 1000 years. (6) Modeling sulfate attack and cracking due to ettringite formation. A detailed example for this case is provided in a separate article by the authors (Sarkar et al. 2010). Finally, based on the computed results, the sensitive input parameters for this type of modeling are identified and discussed. The chemical speciation behavior of substances is calculated for a batch system and also in combination with transport and within a three layer system. This includes release from a barrier to the surrounding soil as a function of time. As input for the simulations, the physical and chemical properties of the

  15. Multiphysics Modelling of Sodium Sulfur Battery

    Science.gov (United States)

    Mason, Jerry Hunter

    overpotential is significantly higher in the porous region of the cathode as was predicted by models in the literature. Overpotential is also high on the electrolyte surface and wall. Alternative electrode configurations with high resistive layers recommended by previous researchers also produce areas of high potential gradient. New electrode designs including conductivity gradients and porous media property variations are simulated and compared to previous designs and then recommendations are made for optimum cell operating conditions.

  16. RELAP-7 Beta Release: Summary of Capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Martineau, Richard C. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Zhang, Hongbin [Idaho National Lab. (INL), Idaho Falls, ID (United States); Zhao, Haihua [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-12-01

    RELAP-7 is a nuclear systems safety analysis code being developed at the Idaho National Laboratory (INL). Building upon the decades of software development at the INL, we began the development of RELAP-7 in 2011 to support the Risk Informed Safety Margins Characterization (RISMC) Pathway. As part of this development, the first lines of RELAP-7 code were committed to the software revision control repository on November 7th, 2011. The overall design goal of RELAP-7 is to take advantage of the previous thirty years of advancements in computer architecture, software design, numerical methods, and physical models in order to provide capabilities needed for the RISMC methodology and to support nuclear power safety analysis. RELAP-7 is built using the INL’s modern scientific software development framework, MOOSE (Multi-physics Object Oriented Simulation Environment). MOOSE provides improved numerical calculations (including higher-order integration in both space and time, yielding converged second-order accuracy). The RELAP-7 code structure is based on multiple physical component models such as pipes, junctions, pumps, etc. Each component can have options for different fluid models such as single- and two-phase flow. This component-based and physics-based software architecture allows RELAP-7 to adopt different physical models for different applications. A relatively new two-phase hydrodynamic model, termed the ''7-Equation model'' for two phasic pressures, velocities, energies, and volumetric fraction, is incorporated into RELAP-7 for liquid-gas (water-steam) flows. This new model allows second-order integration because it is well-posed, which will reduce the numerical error associated with traditional systems analysis codes. In this paper, we provide a RELAP-7 capability list describing analysis features, range of applicability, and reactor components that will be available for the December 15th, 2014 beta release of the software.

  17. A High Fidelity Multiphysics Framework for Modeling CRUD Deposition on PWR Fuel Rods

    Science.gov (United States)

    Walter, Daniel John

    Corrosion products on the fuel cladding surfaces within pressurized water reactor fuel assemblies have had a significant impact on reactor operation. These types of deposits are referred to as CRUD and can lead to power shifts, as a consequence of the accumulation of solid boron phases on the fuel rod surfaces. Corrosion deposits can also lead to fuel failure resulting from localized corrosion, where the increased thermal resistance of the deposit leads to higher cladding temperatures. The prediction of these occurrences requires a comprehensive model of local thermal hydraulic and chemical processes occurring in close proximity to the cladding surface, as well as their driving factors. Such factors include the rod power distribution, coolant corrosion product concentration, as well as the feedbacks between heat transfer, fluid dynamics, chemistry, and neutronics. To correctly capture the coupled physics and corresponding feedbacks, a high fidelity framework is developed that predicts three-dimensional CRUD deposition on a rod-by-rod basis. Multiphysics boundary conditions resulting from the coupling of heat transfer, fluid dynamics, coolant chemistry, CRUD deposition, neutron transport, and nuclide transmutation inform the CRUD deposition solver. Through systematic parametric sensitivity studies of the CRUD property inputs, coupled boundary conditions, and multiphysics feedback mechanisms, the most important variables of multiphysics CRUD modeling are identified. Moreover, the modeling framework is challenged with a blind comparison of plant data to predictions by a simulation of a sub-assembly within the Seabrook nuclear plant that experienced CRUD induced fuel failures. The physics within the computational framework are loosely coupled via an operator-splitting technique. A control theory approach is adopted to determine the temporal discretization at which to execute a data transfer from one physics to another. The coupled stepsize selection is viewed as a

  18. Integrated Physics Advances in Simulation of Wave Interactions with Extended MHD Phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Batchelor, Donald B [ORNL; D' Azevedo, Eduardo [ORNL; Bateman, Glenn [Lehigh University, Bethlehem, PA; Bernholdt, David E [ORNL; Berry, Lee A [ORNL; Bonoli, P. [Massachusetts Institute of Technology (MIT); Bramley, R [Indiana University; Breslau, J. [Princeton Plasma Physics Laboratory (PPPL); Chance, M. [Princeton Plasma Physics Laboratory (PPPL); Chen, J. [Princeton Plasma Physics Laboratory (PPPL); Choi, M. [General Atomics; Elwasif, Wael R [ORNL; Fu, GuoYong [Princeton Plasma Physics Laboratory (PPPL); Harvey, R. W. [CompX, Del Mar, CA; Houlberg, Wayne A [ORNL; Jaeger, Erwin Frederick [ORNL; Jardin, S. C. [Princeton Plasma Physics Laboratory (PPPL); Keyes, David E [Columbia University; Klasky, Scott A [ORNL; Kruger, Scott [Tech-X Corporation; Ku, Long-Poe [Princeton Plasma Physics Laboratory (PPPL); McCune, Douglas [Princeton Plasma Physics Laboratory (PPPL); Schissel, D. [General Atomics; Schnack, D. [University of Wisconsin; Wright, J. C. [Massachusetts Institute of Technology (MIT)

    2007-06-01

    The broad scientific objectives of the SWIM (Simulation of Wave Interaction with MHD) project are: (A) To improve our understanding of interactions that both RF wave and particle sources have on extended-MHD phenomena, and to substantially improve our capability for predicting and optimizing the performance of burning plasmas in devices such as ITER: and (B) To develop an integrated computational system for treating multi-physics phenomena with the required flexibility and extensibility to serve as a prototype for the Fusion Simulation Project (FSP).

  19. Integrated physics advances in simulation of wave interactions with extended MHD phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Batchelor, D B [ORNL (United States); D' Azevedo, E [ORNL (United States); Bateman, G [Lehigh (United States)] (and others)

    2007-07-15

    The broad scientific objectives of the SWIM (Simulation of Wave Interaction with MHD) project are: (A) To improve our understanding of interactions that both RF wave and particle sources have on extended-MHD phenomena, and to substantially improve our capability for predicting and optimizing the performance of burning plasmas in devices such as ITER: and (B) To develop an integrated computational system for treating multi-physics phenomena with the required flexibility and extensibility to serve as a prototype for the Fusion Simulation Project (FSP)

  20. Simulation of wave interactions with MHD

    Energy Technology Data Exchange (ETDEWEB)

    Batchelor, D; Bernholdt, D; Berry, L; Elwasif, W; Jaeger, E; Keyes, D; Klasky, S [Oak Ridge National Laboratory, Oak Ridge, TN 37331 (United States); Alba, C; Choi, M [General Atomics, San Diego, CA 92186 (United States); Bateman, G [Lehigh University, Bethlehem, PA 18015 (United States); Bonoli, P [Plasma Science and Fusion Center, MTT, Cambridge, MA 02139 (United States); Bramley, R [Indiana University, Bloomington, IN 47405 (United States); Breslau, J; Chance, M; Chen, J; Fu, G; Jardin, S [Princeton Plasma Physics Laboratory, Princeton, NJ 08543 (United States); Harvey, R [CompX, Del Mar, CA 92014 (United States); Jenkins, T [University of Wisconsin, Madison, WI 53706 (United States); Kruger, S [Tech-X, Boulder, CO 80303 (United States)], E-mail: batchelordb@ornl.gov (and others)

    2008-07-15

    The broad scientific objectives of the SWIM (Simulation 01 Wave Interaction with MHD) project are twofold: (1) improve our understanding of interactions that both radio frequency (RF) wave and particle sources have on extended-MHD phenomena, and to substantially improve our capability for predicting and optimizing the performance of burning plasmas in devices such as ITER: and (2) develop an integrated computational system for treating multiphysics phenomena with the required flexibility and extensibility to serve as a prototype for the Fusion Simulation Project. The Integrated Plasma Simulator (IPS) has been implemented. Presented here are initial physics results on RP effects on MHD instabilities in tokamaks as well as simulation results for tokamak discharge evolution using the IPS.

  1. Simulation of wave interactions with MHD

    Energy Technology Data Exchange (ETDEWEB)

    Batchelor, Donald B [ORNL; Abla, G [General Atomics, San Diego; Bateman, Glenn [Lehigh University, Bethlehem, PA; Bernholdt, David E [ORNL; Berry, Lee A [ORNL; Bonoli, P. [Massachusetts Institute of Technology (MIT); Bramley, R [Indiana University; Breslau, J. [Princeton Plasma Physics Laboratory (PPPL); Chance, M. [Princeton Plasma Physics Laboratory (PPPL); Chen, J. [Princeton Plasma Physics Laboratory (PPPL); Choi, M. [General Atomics; Elwasif, Wael R [ORNL; Fu, GuoYong [Princeton Plasma Physics Laboratory (PPPL); Harvey, R. W. [CompX, Del Mar, CA; Jaeger, Erwin Frederick [ORNL; Jardin, S. C. [Princeton Plasma Physics Laboratory (PPPL); Jenkins, T [University of Wisconsin; Keyes, David E [Columbia University; Klasky, Scott A [ORNL; Kruger, Scott [Tech-X Corporation; Ku, Long-Poe [Princeton Plasma Physics Laboratory (PPPL); Lynch, Vickie E [ORNL; McCune, Douglas [Princeton Plasma Physics Laboratory (PPPL); Ramos, J. [Massachusetts Institute of Technology (MIT); Schissel, D. [General Atomics; Schnack, [University of Wisconsin; Wright, J. [Massachusetts Institute of Technology (MIT)

    2008-07-01

    The broad scientific objectives of the SWIM (Simulation of Wave Interaction with MHD) project are twofold: (1) improve our understanding of interactions that both radio frequency (RF) wave and particle sources have on extended-MHD phenomena, and to substantially improve our capability for predicting and optimizing the performance of burning plasmas in devices such as ITER: and (2) develop an integrated computational system for treating multiphysics phenomena with the required flexibility and extensibility to serve as a prototype for the Fusion Simulation Project. The Integrated Plasma Simulator (IPS) has been implemented. Presented here are initial physics results on RF effects on MHD instabilities in tokamaks as well as simulation results for tokamak discharge evolution using the IPS.

  2. Software Abstractions and Methodologies for HPC Simulation Codes on Future Architectures

    Directory of Open Access Journals (Sweden)

    Anshu Dubey

    2014-07-01

    Full Text Available Simulations with multi-physics modeling have become crucial to many science and engineering fields, and multi-physics capable scientific software is as important to these fields as instruments and facilities are to experimental sciences. The current generation of mature multi-physics codes would have sustainably served their target communities with modest amount of ongoing investment for enhancing capabilities. However, the revolution occurring in the hardware architecture has made it necessary to tackle the parallelism and performance management in these codes at multiple levels. The requirements of various levels are often at cross-purposes with one another, and therefore hugely complicate the software design. All of these considerations make it essential to approach this challenge cooperatively as a community. We conducted a series of workshops under an NSF-SI2 conceptualization grant to get input from various stakeholders, and to identify broad approaches that might lead to a solution. In this position paper we detail the major concerns articulated by the application code developers, and emerging trends in utilization of programming abstractions that we found through these workshops.

  3. Design and multiphysics analysis of a 176 MHz continuous-wave radio-frequency quadrupole

    Directory of Open Access Journals (Sweden)

    S. V. Kutsaev

    2014-07-01

    Full Text Available We have developed a new design for a 176 MHz cw radio-frequency quadrupole (RFQ for the SARAF upgrade project. At this frequency, the proposed design is a conventional four-vane structure. The main design goals are to provide the highest possible shunt impedance while limiting the required rf power to about 120 kW for reliable cw operation, and the length to about 4 meters. If built as designed, the proposed RFQ will be the first four-vane cw RFQ built as a single cavity (no resonant coupling required that does not require π-mode stabilizing loops or dipole rods. For this, we rely on very detailed 3D simulations of all aspects of the structure and the level of machining precision achieved on the recently developed ATLAS upgrade RFQ. A full 3D model of the structure including vane modulation was developed. The design was optimized using electromagnetic and multiphysics simulations. Following the choice of the vane type and geometry, the vane undercuts were optimized to produce a flat field along the structure. The final design has good mode separation and should not need dipole rods if built as designed, but their effect was studied in the case of manufacturing errors. The tuners were also designed and optimized to tune the main mode without affecting the field flatness. Following the electromagnetic (EM design optimization, a multiphysics engineering analysis of the structure was performed. The multiphysics analysis is a coupled electromagnetic, thermal and mechanical analysis. The cooling channels, including their paths and sizes, were optimized based on the limiting temperature and deformation requirements. The frequency sensitivity to the RFQ body and vane cooling water temperatures was carefully studied in order to use it for frequency fine-tuning. Finally, an inductive rf power coupler design based on the ATLAS RFQ coupler was developed and simulated. The EM design optimization was performed using cst Microwave Studio and the results

  4. A Coupled Field Multiphysics Modeling Approach to Investigate RF MEMS Switch Failure Modes under Various Operational Conditions

    Directory of Open Access Journals (Sweden)

    Khaled Sadek

    2009-10-01

    Full Text Available In this paper, the reliability of capacitive shunt RF MEMS switches have been investigated using three dimensional (3D coupled multiphysics finite element (FE analysis. The coupled field analysis involved three consecutive multiphysics interactions. The first interaction is characterized as a two-way sequential electromagnetic (EM-thermal field coupling. The second interaction represented a one-way sequential thermal-structural field coupling. The third interaction portrayed a two-way sequential structural-electrostatic field coupling. An automated substructuring algorithm was utilized to reduce the computational cost of the complicated coupled multiphysics FE analysis. The results of the substructured FE model with coupled field analysis is shown to be in good agreement with the outcome of previously published experimental and numerical studies. The current numerical results indicate that the pull-in voltage and the buckling temperature of the RF switch are functions of the microfabrication residual stress state, the switch operational frequency and the surrounding packaging temperature. Furthermore, the current results point out that by introducing proper mechanical approaches such as corrugated switches and through-holes in the switch membrane, it is possible to achieve reliable pull-in voltages, at various operating temperatures. The performed analysis also shows that by controlling the mean and gradient residual stresses, generated during microfabrication, in conjunction with the proposed mechanical approaches, the power handling capability of RF MEMS switches can be increased, at a wide range of operational frequencies. These design features of RF MEMS switches are of particular importance in applications where a high RF power (frequencies above 10 GHz and large temperature variations are expected, such as in satellites and airplane condition monitoring.

  5. From 3D tissue data to impedance using Simpleware ScanFE+IP and COMSOL Multiphysics – a tutorial

    Directory of Open Access Journals (Sweden)

    Fred-Johan Pettersen

    2011-04-01

    Full Text Available Tools such as Simpleware ScanIP+FE and COMSOL Multiphysics allow us to gain a better understanding of bioimpedance measurements without actually doing the measurements. This tutorial will cover the steps needed to go from a 3D voxel data set to a model that can be used to simulate a trans-impedance measurement. Geometrical input data used in this tutorial are from MRI scan of a human thigh, which are converted to a mesh using Simpleware ScanIP+FE. The mesh is merged with electrical properties for the relevant tissues, and a simulation is done in COMSOL Multiphysics. Available numerical output data are trans-impedance, contribu- tion from different tissues to final trans-impedance, and voltages at electrodes. Available volume output data are normal and reciprocal current densities, potential, sensitivity, and volume impedance sensitivity. The output data are presented as both numbers and graphs. The tutorial will be useful even if data from other sources such as VOXEL-MAN or CT scans are used.>doi:10.5617/jeb.173 J Electr Bioimp, vol. 2, pp. 13-32, 2011

  6. Evaluation of HFIR LEU Fuel Using the COMSOL Multiphysics Platform

    Energy Technology Data Exchange (ETDEWEB)

    Primm, Trent [ORNL; Ruggles, Arthur [ORNL; Freels, James D [ORNL

    2009-03-01

    A finite element computational approach to simulation of the High Flux Isotope Reactor (HFIR) Core Thermal-Fluid behavior is developed. These models were developed to facilitate design of a low enriched core for the HFIR, which will have different axial and radial flux profiles from the current HEU core and thus will require fuel and poison load optimization. This report outlines a stepwise implementation of this modeling approach using the commercial finite element code, COMSOL, with initial assessment of fuel, poison and clad conduction modeling capability, followed by assessment of mating of the fuel conduction models to a one dimensional fluid model typical of legacy simulation techniques for the HFIR core. The model is then extended to fully couple 2-dimensional conduction in the fuel to a 2-dimensional thermo-fluid model of the coolant for a HFIR core cooling sub-channel with additional assessment of simulation outcomes. Finally, 3-dimensional simulations of a fuel plate and cooling channel are presented.

  7. Multiscale Multiphysics Developments for Accident Tolerant Fuel Concepts

    Energy Technology Data Exchange (ETDEWEB)

    Gamble, K. A. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hales, J. D. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Yu, J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Zhang, Y. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bai, X. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Andersson, D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Patra, A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wen, W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tome, C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Baskes, M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Martinez, E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Stanek, C. R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Miao, Y. [Argonne National Lab. (ANL), Argonne, IL (United States); Ye, B. [Argonne National Lab. (ANL), Argonne, IL (United States); Hofman, G. L. [Argonne National Lab. (ANL), Argonne, IL (United States); Yacout, A. M. [Argonne National Lab. (ANL), Argonne, IL (United States); Liu, W. [ANATECH Corp., San Diego, CA (United States)

    2015-09-01

    U3Si2 and iron-chromium-aluminum (Fe-Cr-Al) alloys are two of many proposed accident-tolerant fuel concepts for the fuel and cladding, respectively. The behavior of these materials under normal operating and accident reactor conditions is not well known. As part of the Department of Energy’s Accident Tolerant Fuel High Impact Problem program significant work has been conducted to investigate the U3Si2 and FeCrAl behavior under reactor conditions. This report presents the multiscale and multiphysics effort completed in fiscal year 2015. The report is split into four major categories including Density Functional Theory Developments, Molecular Dynamics Developments, Mesoscale Developments, and Engineering Scale Developments. The work shown here is a compilation of a collaborative effort between Idaho National Laboratory, Los Alamos National Laboratory, Argonne National Laboratory and Anatech Corp.

  8. Efficient topology optimisation of multiscale and multiphysics problems

    DEFF Research Database (Denmark)

    Alexandersen, Joe

    The aim of this Thesis is to present efficient methods for optimising high-resolution problems of a multiscale and multiphysics nature. The Thesis consists of two parts: one treating topology optimisation of microstructural details and the other treating topology optimisation of conjugate heat...... transfer problems. Part I begins with an introduction to the concept of microstructural details in the context of topology optimisation. Relevant literature is briefly reviewed and problems with existing methodologies are identified. The proposed methodology and its strengths are summarised. Details...... the computational cost of treating structures with fully-resolved microstructural details. The methodology is further applied to examples, where it is shown that it ensures connectivity of the microstructural details and that forced periodicity of the microstructural details can yield an implicit robustness to load...

  9. Multiphysics modeling of the steel continuous casting process

    Science.gov (United States)

    Hibbeler, Lance C.

    This work develops a macroscale, multiphysics model of the continuous casting of steel. The complete model accounts for the turbulent flow and nonuniform distribution of superheat in the molten steel, the elastic-viscoplastic thermal shrinkage of the solidifying shell, the heat transfer through the shell-mold interface with variable gap size, and the thermal distortion of the mold. These models are coupled together with carefully constructed boundary conditions with the aid of reduced-order models into a single tool to investigate behavior in the mold region, for practical applications such as predicting ideal tapers for a beam-blank mold. The thermal and mechanical behaviors of the mold are explored as part of the overall modeling effort, for funnel molds and for beam-blank molds. These models include high geometric detail and reveal temperature variations on the mold-shell interface that may be responsible for cracks in the shell. Specifically, the funnel mold has a column of mold bolts in the middle of the inside-curve region of the funnel that disturbs the uniformity of the hot face temperatures, which combined with the bending effect of the mold on the shell, can lead to longitudinal facial cracks. The shoulder region of the beam-blank mold shows a local hot spot that can be reduced with additional cooling in this region. The distorted shape of the funnel mold narrow face is validated with recent inclinometer measurements from an operating caster. The calculated hot face temperatures and distorted shapes of the mold are transferred into the multiphysics model of the solidifying shell. The boundary conditions for the first iteration of the multiphysics model come from reduced-order models of the process; one such model is derived in this work for mold heat transfer. The reduced-order model relies on the physics of the solution to the one-dimensional heat-conduction equation to maintain the relationships between inputs and outputs of the model. The geometric

  10. Structure-coupled multiphysics imaging in geophysical sciences

    Science.gov (United States)

    Gallardo, Luis A.; Meju, Max A.

    2011-03-01

    Multiphysics imaging or data inversion is of growing importance in many branches of science and engineering. In geophysical sciences, there is a need for combining information from multiple images acquired using different imaging devices and/or modalities because of the potential for accurate predictions. The major challenges are how to combine disparate data from unrelated physical phenomena, taking into account the different spatial scales of the measurement devices, model complexities, and how to quantify the associated uncertainties. This review paper summarizes the role played by the structural gradients-based approach for coupling fundamentally different physical fields in (mainly) geophysical inversion, develops further understanding of this approach to guide newcomers to the field, and defines the main challenges and directions for future research that may be useful in other fields of science and engineering.

  11. Shiga toxin-producing Escherichia coli in meat: a preliminary simulation study on detection capabilities for three sampling methods

    Science.gov (United States)

    The objective of this simulation study is to determine which sampling method (Cozzini core sampler, core drill shaving, and N-60 surface excision) will better detect Shiga Toxin-producing Escherichia coli (STEC) at varying levels of contamination when present in the meat. 1000 simulated experiments...

  12. Capability Paternalism

    NARCIS (Netherlands)

    Claassen, R.J.G.

    2014-01-01

    A capability approach prescribes paternalist government actions to the extent that it requires the promotion of specific functionings, instead of the corresponding capabilities. Capability theorists have argued that their theories do not have much of these paternalist implications, since promoting c

  13. Investigation of supercomputer capabilities for the scalable numerical simulation of computational fluid dynamics problems in industrial applications

    Science.gov (United States)

    Kozelkov, A. S.; Kurulin, V. V.; Lashkin, S. V.; Shagaliev, R. M.; Yalozo, A. V.

    2016-08-01

    Two main issues of the efficient usage of computational fluid dynamics (CFD) in industrial applications—simulation of turbulence and speedup of computations—are analyzed. Results of the investigation of potentials of the eddy-resolving approaches to turbulence simulation in industrial applications with the use of arbitrary unstructured grids are presented. Algorithms for speeding up the scalable high-performance computations based on multigrid technologies are proposed.

  14. Study on the usage of a commercial software (Comsol-Multiphysics®) for dislocation multiplication model

    Science.gov (United States)

    Gallien, B.; Albaric, M.; Duffar, T.; Kakimoto, K.; M'Hamdi, M.

    2017-01-01

    Elaboration of silicon ingots for photovoltaic application in Directional Solidification furnace leads to formation of dislocations mainly due to thermoelastic stresses, which impact photovoltaic conversion rate. Several research teams have created numerical simulation models using home-made software in order to study dislocation multiplication and predict the dislocation density and residual stresses inside ingots after elaboration. In this study, the commercial software Comsol-Multiphysics® is used to calculate the evolution of dislocation density during the ingot solidification and cooling. Thermo-elastic stress, due to temperature field inside the ingot during elaboration, is linked to the evolution of the dislocation density by the Alexander and Haasen model (A&H model). The purpose of this study is to show relevance of commercial software to predict dislocation density in ingots. In a first approach, A&H physical model is introduced for a 2D axisymmetric geometry. After a short introduction, modification of Comsol® software is presented in order to include A&H equations. This numerical model calculates dislocation density and plastic stress continuously during ingot solidification and cooling. Results of this model are then compared to home-made simulation created by the teams at Kyushu university and NTNU. Results are also compared to characterization of a silicon ingot elaborated in a gradient freeze furnace. Both of these comparisons shows the relevance of using a commercial code, as Comsol®, to predict dislocations multiplication in a silicon ingot during elaboration.

  15. A finite element framework for multiscale/multiphysics analysis of structures with complex microstructures

    Science.gov (United States)

    Varghese, Julian

    This research work has contributed in various ways to help develop a better understanding of textile composites and materials with complex microstructures in general. An instrumental part of this work was the development of an object-oriented framework that made it convenient to perform multiscale/multiphysics analyses of advanced materials with complex microstructures such as textile composites. In addition to the studies conducted in this work, this framework lays the groundwork for continued research of these materials. This framework enabled a detailed multiscale stress analysis of a woven DCB specimen that revealed the effect of the complex microstructure on the stress and strain energy release rate distribution along the crack front. In addition to implementing an oxidation model, the framework was also used to implement strategies that expedited the simulation of oxidation in textile composites so that it would take only a few hours. The simulation showed that the tow architecture played a significant role in the oxidation behavior in textile composites. Finally, a coupled diffusion/oxidation and damage progression analysis was implemented that was used to study the mechanical behavior of textile composites under mechanical loading as well as oxidation. A parametric study was performed to determine the effect of material properties and the number of plies in the laminate on its mechanical behavior. The analyses indicated a significant effect of the tow architecture and other parameters on the damage progression in the laminates.

  16. Monte Carlo-based multiphysics coupling analysis of x-ray pulsar telescope

    Science.gov (United States)

    Li, Liansheng; Deng, Loulou; Mei, Zhiwu; Zuo, Fuchang; Zhou, Hao

    2015-10-01

    X-ray pulsar telescope (XPT) is a complex optical payload, which involves optical, mechanical, electrical and thermal disciplines. The multiphysics coupling analysis (MCA) plays an important role in improving the in-orbit performance. However, the conventional MCA methods encounter two serious problems in dealing with the XTP. One is that both the energy and reflectivity information of X-ray can't be taken into consideration, which always misunderstands the essence of XPT. Another is that the coupling data can't be transferred automatically among different disciplines, leading to computational inefficiency and high design cost. Therefore, a new MCA method for XPT is proposed based on the Monte Carlo method and total reflective theory. The main idea, procedures and operational steps of the proposed method are addressed in detail. Firstly, it takes both the energy and reflectivity information of X-ray into consideration simultaneously. And formulate the thermal-structural coupling equation and multiphysics coupling analysis model based on the finite element method. Then, the thermalstructural coupling analysis under different working conditions has been implemented. Secondly, the mirror deformations are obtained using construction geometry function. Meanwhile, the polynomial function is adopted to fit the deformed mirror and meanwhile evaluate the fitting error. Thirdly, the focusing performance analysis of XPT can be evaluated by the RMS. Finally, a Wolter-I XPT is taken as an example to verify the proposed MCA method. The simulation results show that the thermal-structural coupling deformation is bigger than others, the vary law of deformation effect on the focusing performance has been obtained. The focusing performances of thermal-structural, thermal, structural deformations have degraded 30.01%, 14.35% and 7.85% respectively. The RMS of dispersion spot are 2.9143mm, 2.2038mm and 2.1311mm. As a result, the validity of the proposed method is verified through

  17. An integrated multiphysics model for friction stir welding of 6061 Aluminum alloy

    Directory of Open Access Journals (Sweden)

    M Nourani

    2016-09-01

    Full Text Available This article presents a new, combined ‘integrated’- ‘multiphysics’ model of friction stir welding (FSW where a set of governing equations from non-Newtonian incompressible fluid dynamics, conductive and convective heat transfer, and plain stress solid mechanics have been coupled for calculating the process variables and material behaviour both during and after welding. More specifically, regarding the multiphysics feature, the model is capable of simultaneously predicting the local distribution, location and magnitude of maximum temperature, strain, and strain rate fields around the tool pin during the process; while for the integrated (post-analysis part, the above predictions have been used to study the microstructure and residual stress field of welded parts within the same developed code. A slip/stick condition between the tool and workpiece, friction and deformation heat source, convection and conduction heat transfer in the workpiece, a solid mechanics-based viscosity definition, and the Zener-Hollomon- based rigid-viscoplastic material properties with solidus cut-off temperature and empirical softening regime have been employed. In order to validate all the predicted variables collectively, the model has been compared to a series of published case studies on individual/limited set of variables, as well as in-house experiments on FSW of aluminum 6061.

  18. Experimental Evaluation of Acoustic Engine Liner Models Developed with COMSOL Multiphysics

    Science.gov (United States)

    Schiller, Noah H.; Jones, Michael G.; Bertolucci, Brandon

    2017-01-01

    Accurate modeling tools are needed to design new engine liners capable of reducing aircraft noise. The purpose of this study is to determine if a commercially-available finite element package, COMSOL Multiphysics, can be used to accurately model a range of different acoustic engine liner designs, and in the process, collect and document a benchmark dataset that can be used in both current and future code evaluation activities. To achieve these goals, a variety of liner samples, ranging from conventional perforate-over-honeycomb to extended-reaction designs, were installed in one wall of the grazing flow impedance tube at the NASA Langley Research Center. The liners were exposed to high sound pressure levels and grazing flow, and the effect of the liner on the sound field in the flow duct was measured. These measurements were then compared with predictions. While this report only includes comparisons for a subset of the configurations, the full database of all measurements and predictions is available in electronic format upon request. The results demonstrate that both conventional perforate-over-honeycomb and extended-reaction liners can be accurately modeled using COMSOL. Therefore, this modeling tool can be used with confidence to supplement the current suite of acoustic propagation codes, and ultimately develop new acoustic engine liners designed to reduce aircraft noise.

  19. Multi-Physics Computational Modeling Tool for Materials Damage Assessment Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation proposed here is to provide a multi-physics modeling tool for materials damage assessment for application to future aircraft design. The software...

  20. General linear methods and friends: Toward efficient solutions of multiphysics problems

    Science.gov (United States)

    Sandu, Adrian

    2017-07-01

    Time dependent multiphysics partial differential equations are of great practical importance as they model diverse phenomena that appear in mechanical and chemical engineering, aeronautics, astrophysics, meteorology and oceanography, financial modeling, environmental sciences, etc. There is no single best time discretization for the complex multiphysics systems of practical interest. We discuss "multimethod" approaches that combine different time steps and discretizations using the rigourous frameworks provided by Partitioned General Linear Methods and Generalize-structure Additive Runge Kutta Methods..

  1. Multiscale and Multiphysics Modeling of Additive Manufacturing of Advanced Materials

    Science.gov (United States)

    Liou, Frank; Newkirk, Joseph; Fan, Zhiqiang; Sparks, Todd; Chen, Xueyang; Fletcher, Kenneth; Zhang, Jingwei; Zhang, Yunlu; Kumar, Kannan Suresh; Karnati, Sreekar

    2015-01-01

    The objective of this proposed project is to research and develop a prediction tool for advanced additive manufacturing (AAM) processes for advanced materials and develop experimental methods to provide fundamental properties and establish validation data. Aircraft structures and engines demand materials that are stronger, useable at much higher temperatures, provide less acoustic transmission, and enable more aeroelastic tailoring than those currently used. Significant improvements in properties can only be achieved by processing the materials under nonequilibrium conditions, such as AAM processes. AAM processes encompass a class of processes that use a focused heat source to create a melt pool on a substrate. Examples include Electron Beam Freeform Fabrication and Direct Metal Deposition. These types of additive processes enable fabrication of parts directly from CAD drawings. To achieve the desired material properties and geometries of the final structure, assessing the impact of process parameters and predicting optimized conditions with numerical modeling as an effective prediction tool is necessary. The targets for the processing are multiple and at different spatial scales, and the physical phenomena associated occur in multiphysics and multiscale. In this project, the research work has been developed to model AAM processes in a multiscale and multiphysics approach. A macroscale model was developed to investigate the residual stresses and distortion in AAM processes. A sequentially coupled, thermomechanical, finite element model was developed and validated experimentally. The results showed the temperature distribution, residual stress, and deformation within the formed deposits and substrates. A mesoscale model was developed to include heat transfer, phase change with mushy zone, incompressible free surface flow, solute redistribution, and surface tension. Because of excessive computing time needed, a parallel computing approach was also tested. In addition

  2. A Posteriori Analysis of Adaptive Multiscale Operator Decomposition Methods for Multiphysics Problems

    Energy Technology Data Exchange (ETDEWEB)

    Donald Estep; Michael Holst; Simon Tavener

    2010-02-08

    This project was concerned with the accurate computational error estimation for numerical solutions of multiphysics, multiscale systems that couple different physical processes acting across a large range of scales relevant to the interests of the DOE. Multiscale, multiphysics models are characterized by intimate interactions between different physics across a wide range of scales. This poses significant computational challenges addressed by the proposal, including: (1) Accurate and efficient computation; (2) Complex stability; and (3) Linking different physics. The research in this project focused on Multiscale Operator Decomposition methods for solving multiphysics problems. The general approach is to decompose a multiphysics problem into components involving simpler physics over a relatively limited range of scales, and then to seek the solution of the entire system through some sort of iterative procedure involving solutions of the individual components. MOD is a very widely used technique for solving multiphysics, multiscale problems; it is heavily used throughout the DOE computational landscape. This project made a major advance in the analysis of the solution of multiscale, multiphysics problems.

  3. Multiscale Multiphysics and Multidomain Models I: Basic Theory.

    Science.gov (United States)

    Wei, Guo-Wei

    2013-12-01

    This work extends our earlier two-domain formulation of a differential geometry based multiscale paradigm into a multidomain theory, which endows us the ability to simultaneously accommodate multiphysical descriptions of aqueous chemical, physical and biological systems, such as fuel cells, solar cells, nanofluidics, ion channels, viruses, RNA polymerases, molecular motors and large macromolecular complexes. The essential idea is to make use of the differential geometry theory of surfaces as a natural means to geometrically separate the macroscopic domain of solvent from the microscopic domain of solute, and dynamically couple continuum and discrete descriptions. Our main strategy is to construct energy functionals to put on an equal footing of multiphysics, including polar (i.e., electrostatic) solvation, nonpolar solvation, chemical potential, quantum mechanics, fluid mechanics, molecular mechanics, coarse grained dynamics and elastic dynamics. The variational principle is applied to the energy functionals to derive desirable governing equations, such as multidomain Laplace-Beltrami (LB) equations for macromolecular morphologies, multidomain Poisson-Boltzmann (PB) equation or Poisson equation for electrostatic potential, generalized Nernst-Planck (NP) equations for the dynamics of charged solvent species, generalized Navier-Stokes (NS) equation for fluid dynamics, generalized Newton's equations for molecular dynamics (MD) or coarse-grained dynamics and equation of motion for elastic dynamics. Unlike the classical PB equation, our PB equation is an integral-differential equation due to solvent-solute interactions. To illustrate the proposed formalism, we have explicitly constructed three models, a multidomain solvation model, a multidomain charge transport model and a multidomain chemo-electro-fluid-MD-elastic model. Each solute domain is equipped with distinct surface tension, pressure, dielectric function, and charge density distribution. In addition to long

  4. Capability ethics

    NARCIS (Netherlands)

    I.A.M. Robeyns (Ingrid)

    2012-01-01

    textabstractThe capability approach is one of the most recent additions to the landscape of normative theories in ethics and political philosophy. Yet in its present stage of development, the capability approach is not a full-blown normative theory, in contrast to utilitarianism, deontological

  5. Capability ethics

    NARCIS (Netherlands)

    I.A.M. Robeyns (Ingrid)

    2012-01-01

    textabstractThe capability approach is one of the most recent additions to the landscape of normative theories in ethics and political philosophy. Yet in its present stage of development, the capability approach is not a full-blown normative theory, in contrast to utilitarianism, deontological theor

  6. Capability ethics

    NARCIS (Netherlands)

    I.A.M. Robeyns (Ingrid)

    2012-01-01

    textabstractThe capability approach is one of the most recent additions to the landscape of normative theories in ethics and political philosophy. Yet in its present stage of development, the capability approach is not a full-blown normative theory, in contrast to utilitarianism, deontological theor

  7. Adding Complex Terrain and Stable Atmospheric Condition Capability to the Simulator for On/Offshore Wind Farm Applications (SOWFA) (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Churchfield, M. J.

    2013-06-01

    This presentation describes changes made to NREL's OpenFOAM-based wind plant aerodynamics solver so that it can compute the stably stratified atmospheric boundary layer and flow over terrain. Background about the flow solver, the Simulator for Off/Onshore Wind Farm Applications (SOWFA) is given, followed by details of the stable stratification/complex terrain modifications to SOWFA, along with some preliminary results calculations of a stable atmospheric boundary layer and flow over a simple set of hills.

  8. Experimentally validated multiphysics computational model of focusing and shock wave formation in an electromagnetic lithotripter.

    Science.gov (United States)

    Fovargue, Daniel E; Mitran, Sorin; Smith, Nathan B; Sankin, Georgy N; Simmons, Walter N; Zhong, Pei

    2013-08-01

    A multiphysics computational model of the focusing of an acoustic pulse and subsequent shock wave formation that occurs during extracorporeal shock wave lithotripsy is presented. In the electromagnetic lithotripter modeled in this work the focusing is achieved via a polystyrene acoustic lens. The transition of the acoustic pulse through the solid lens is modeled by the linear elasticity equations and the subsequent shock wave formation in water is modeled by the Euler equations with a Tait equation of state. Both sets of equations are solved simultaneously in subsets of a single computational domain within the BEARCLAW framework which uses a finite-volume Riemann solver approach. This model is first validated against experimental measurements with a standard (or original) lens design. The model is then used to successfully predict the effects of a lens modification in the form of an annular ring cut. A second model which includes a kidney stone simulant in the domain is also presented. Within the stone the linear elasticity equations incorporate a simple damage model.

  9. Introducing ZEUS-MP A 3D, Parallel, Multiphysics Code for Astrophysical Fluid Dynamics

    CERN Document Server

    Norman, M L

    2000-01-01

    We describe ZEUS-MP: a Multi-Physics, Massively-Parallel, Message-Passing code for astrophysical fluid dynamics simulations in 3 dimensions. ZEUS-MP is a follow-on to the sequential ZEUS-2D and ZEUS-3D codes developed and disseminated by the Laboratory for Computational Astrophysics (lca.ncsa.uiuc.edu) at NCSA. V1.0 released 1/1/2000 includes the following physics modules: ideal hydrodynamics, ideal MHD, and self-gravity. Future releases will include flux-limited radiation diffusion, thermal heat conduction, two-temperature plasma, and heating and cooling functions. The covariant equations are cast on a moving Eulerian grid with Cartesian, cylindrical, and spherical polar coordinates currently supported. Parallelization is done by domain decomposition and implemented in F77 and MPI. The code is portable across a wide range of platforms from networks of workstations to massively parallel processors. Some parallel performance results are presented as well as an application to turbulent star formation.

  10. Partitioned coupling strategies for multi-physically coupled radiative heat transfer problems

    Science.gov (United States)

    Wendt, Gunnar; Erbts, Patrick; Düster, Alexander

    2015-11-01

    This article aims to propose new aspects concerning a partitioned solution strategy for multi-physically coupled fields including the physics of thermal radiation. Particularly, we focus on the partitioned treatment of electro-thermo-mechanical problems with an additional fourth thermal radiation field. One of the main goals is to take advantage of the flexibility of the partitioned approach to enable combinations of different simulation software and solvers. Within the frame of this article, we limit ourselves to the case of nonlinear thermoelasticity at finite strains, using temperature-dependent material parameters. For the thermal radiation field, diffuse radiating surfaces and gray participating media are assumed. Moreover, we present a robust and fast partitioned coupling strategy for the fourth field problem. Stability and efficiency of the implicit coupling algorithm are improved drawing on several methods to stabilize and to accelerate the convergence. To conclude and to review the effectiveness and the advantages of the additional thermal radiation field several numerical examples are considered to study the proposed algorithm. In particular we focus on an industrial application, namely the electro-thermo-mechanical modeling of the field-assisted sintering technology.

  11. Multiphysics modeling of two-phase film boiling within porous corrosion deposits

    Science.gov (United States)

    Jin, Miaomiao; Short, Michael

    2016-07-01

    Porous corrosion deposits on nuclear fuel cladding, known as CRUD, can cause multiple operational problems in light water reactors (LWRs). CRUD can cause accelerated corrosion of the fuel cladding, increase radiation fields and hence greater exposure risk to plant workers once activated, and induce a downward axial power shift causing an imbalance in core power distribution. In order to facilitate a better understanding of CRUD's effects, such as localized high cladding surface temperatures related to accelerated corrosion rates, we describe an improved, fully-coupled, multiphysics model to simulate heat transfer, chemical reactions and transport, and two-phase fluid flow within these deposits. Our new model features a reformed assumption of 2D, two-phase film boiling within the CRUD, correcting earlier models' assumptions of single-phase coolant flow with wick boiling under high heat fluxes. This model helps to better explain observed experimental values of the effective CRUD thermal conductivity. Finally, we propose a more complete set of boiling regimes, or a more detailed mechanism, to explain recent CRUD deposition experiments by suggesting the new concept of double dryout specifically in thick porous media with boiling chimneys.

  12. A tightly-coupled domain-decomposition approach for highly nonlinear stochastic multiphysics systems

    Science.gov (United States)

    Taverniers, Søren; Tartakovsky, Daniel M.

    2017-02-01

    Multiphysics simulations often involve nonlinear components that are driven by internally generated or externally imposed random fluctuations. When used with a domain-decomposition (DD) algorithm, such components have to be coupled in a way that both accurately propagates the noise between the subdomains and lends itself to a stable and cost-effective temporal integration. We develop a conservative DD approach in which tight coupling is obtained by using a Jacobian-free Newton-Krylov (JfNK) method with a generalized minimum residual iterative linear solver. This strategy is tested on a coupled nonlinear diffusion system forced by a truncated Gaussian noise at the boundary. Enforcement of path-wise continuity of the state variable and its flux, as opposed to continuity in the mean, at interfaces between subdomains enables the DD algorithm to correctly propagate boundary fluctuations throughout the computational domain. Reliance on a single Newton iteration (explicit coupling), rather than on the fully converged JfNK (implicit) coupling, may increase the solution error by an order of magnitude. Increase in communication frequency between the DD components reduces the explicit coupling's error, but makes it less efficient than the implicit coupling at comparable error levels for all noise strengths considered. Finally, the DD algorithm with the implicit JfNK coupling resolves temporally-correlated fluctuations of the boundary noise when the correlation time of the latter exceeds some multiple of an appropriately defined characteristic diffusion time.

  13. Magnetic Circuit Design and Multiphysics Analysis of a Novel MR Damper for Applications under High Velocity

    Directory of Open Access Journals (Sweden)

    Jiajia Zheng

    2014-02-01

    Full Text Available A novel magnetorheological (MR damper with a multistage piston and independent input currents is designed and analyzed. The equivalent magnetic circuit model is investigated along with the relation between magnetic induction density in the working gap and input currents of the electromagnetic coils. Finite element method (FEM is used to analyze the distribution of magnetic field through the MR fluid region. Considering the real situation, coupling equations are presented to analyze the electromagnetic-thermal-flow coupling problems. Software COMSOL is used to analyze the multiphysics, that is, electromagnetic, thermal dynamic, and fluid mechanic. A measurement index involving total damping force, dynamic range, and induction time needed for magnetic coil is put forward to evaluate the performance of the novel multistage MR damper. The simulation results show that it is promising for applications under high velocity and works better when more electromagnetic coils are applied with input currents separately. Besides, in order to reduce energy consumption, it is recommended to apply more electromagnetic coils with relative low currents based on the analysis of pressure drop along the annular gap.

  14. A multiphysics microstructure-resolved model for silicon anode lithium-ion batteries

    Science.gov (United States)

    Wang, Miao; Xiao, Xinran; Huang, Xiaosong

    2017-04-01

    Silicon (Si) is one of the most promising next generation anode materials for lithium-ion batteries (LIBs), but the use of Si in LIBs has been rather limited. The main challenge is its large volume change (up to 300%) during battery cycling. This can lead to the fracture of Si, failure at the interfaces between electrode components, and large dimensional change on the cell level. To optimize the Si electrode/battery design, a model that considers the interactions of different cell components is needed. This paper presents the development of a multiphysics microstructure-resolved model (MRM) for LIB cells with a-Si anode. The model considered the electrochemical reactions, Li transports in electrolyte and electrodes, dimensional changes and stresses, property evolution with the structure, and the coupling relationships. Important model parameters, such as the diffusivity, reaction rate constant, and apparent transfer coefficient, were determined by correlating the simulation results to experiments. The model was validated with experimental results in the literature. The use of this model was demonstrated in a parameter study of Si nanowall|Li cells. The specific and volumetric capacities of the cell as a function of the size, length/size ratio, spacing of the nanostructure, and Li+ concentration in electrolyte were investigated.

  15. Episodic Tremor and Slip (ETS) as a chaotic multiphysics spring

    Science.gov (United States)

    Veveakis, E.; Alevizos, S.; Poulet, T.

    2017-03-01

    Episodic Tremor and Slip (ETS) events display a rich behaviour of slow and accelerated slip with simple oscillatory to complicated chaotic time series. It is commonly believed that the fast events appearing as non volcanic tremors are signatures of deep fluid injection. The fluid source is suggested to be related to the breakdown of hydrous phyllosilicates, mainly the serpentinite group minerals such as antigorite or lizardite that are widespread in the top of the slab in subduction environments. Similar ETS sequences are recorded in different lithologies in exhumed crustal carbonate-rich thrusts where the fluid source is suggested to be the more vigorous carbonate decomposition reaction. If indeed both types of events can be understood and modelled by the same generic fluid release reaction AB(solid) ⇌A(solid) +B(fluid) , the data from ETS sequences in subduction zones reveal a geophysically tractable temporal evolution with no access to the fault zone. This work reviews recent advances in modelling ETS events considering the multiphysics instabilities triggered by the fluid release reaction and develops a thermal-hydraulic-mechanical-chemical oscillator (THMC spring) model for such mineral reactions (like dehydration and decomposition) in Megathrusts. We describe advanced computational methods for THMC instabilities and discuss spectral element and finite element solutions. We apply the presented numerical methods to field examples of this important mechanism and reproduce the temporal signature of the Cascadia and Hikurangi trench with a serpentinite oscillator.

  16. Design Process of IDT Aided by Multiphysics FE Analyses

    Directory of Open Access Journals (Sweden)

    A Martowicz

    2016-09-01

    Full Text Available Presented work is devoted to a design process performed for the interdigital transducer, which is a perspective application for the area of structural health monitoring. In order to obtain the desirable characteristic of the transducer fully coupled numerical analyses were performed in ANSYS Multiphysics software. Utilised finite element models considered both structural dynamics and properties of used piezoelectric material. The process of design improvement was preceded by the sensitivity analysis. In order to search for the best electrode pattern selected geometrical features of the transducer were assumed to vary within allowed ranges. The design parameters, which were taken into account, related to the efficiency of proposed transducer design for the emission of acoustic waves in the monitored structure. The search objectives considered the criteria related to the shape of the beampattern and amplitudes of generated Lamb waves. As a result of the optimization procedure, the simultaneous increase of anti-symmetric mode amplitude and the reduction of undesirable symmetric mode amplitude of generated Lamb waves in the direction perpendicular to the transducer fingers was expected. Another aim of the optimization was to minimize the main lobe width and undesirable contribution of both symmetric and anti-symmetric waves in the parallel direction to the transducer fingers. The response surface method and genetic algorithms were used for fast and effective search through the input design domain.

  17. Multiphysics & Parallel Kinematics Modeling of a 3DOF MEMS Mirror

    Directory of Open Access Journals (Sweden)

    Mamat N.

    2015-01-01

    Full Text Available This paper presents a modeling for a 3DoF electrothermal actuated micro-electro-mechanical (MEMS mirror used to achieve scanning for optical coherence tomography (OCT imaging. The device is integrated into an OCT endoscopic probe, it is desired that the optical scanner have small footprint for minimum invasiveness, large and flat optical aperture for large scanning range, low driving voltage and low power consumption for safety reason. With a footprint of 2mm×2mm, the MEMS scanner which is also called as Tip-Tilt-Piston micro-mirror, can perform two rotations around x and y-axis and a vertical translation along z-axis. This work develops a complete model and experimental characterization. The modeling is divided into two parts: multiphysics characterization of the actuators and parallel kinematics studies of the overall system. With proper experimental procedures, we are able to validate the model via Visual Servoing Platform (ViSP. The results give a detailed overview on the performance of the mirror platform while varying the applied voltage at a stable working frequency. The paper also presents a discussion on the MEMS control system based on several scanning trajectories.

  18. Preliminary Coupling of MATRA Code for Multi-physics Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seongjin; Choi, Jinyoung; Yang, Yongsik; Kwon, Hyouk; Hwang, Daehyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The boundary conditions such as the inlet temperature, mass flux, averaged heat flux, power distributions of the rods, and core geometry is given by constant values or functions of time. These conditions are separately calculated and provided by other codes, such as a neutronics or a system codes, into the MATRA code. In addition, the coupling of several codes in the different physics field is focused and embodied. In this study, multiphysics coupling methods were developed for a subchannel code (MATRA) with neutronics codes (MASTER, DeCART) and a fuel performance code (FRAPCON-3). Preliminary evaluation results for representative sample cases are presented. The MASTER and DeCART codes provide the power distribution of the rods in the core to the MATRA code. In case of the FRAPCON-3 code, the variation of the rod diameter induced by the thermal expansion is yielded and provided. The MATRA code transfers the thermal-hydraulic conditions that each code needs. Moreover, the coupling method with each code is described.

  19. Analysis of Dynamics in Multiphysics Modelling of Active Faults

    Directory of Open Access Journals (Sweden)

    Sotiris Alevizos

    2016-09-01

    Full Text Available Instabilities in Geomechanics appear on multiple scales involving multiple physical processes. They appear often as planar features of localised deformation (faults, which can be relatively stable creep or display rich dynamics, sometimes culminating in earthquakes. To study those features, we propose a fundamental physics-based approach that overcomes the current limitations of statistical rule-based methods and allows a physical understanding of the nucleation and temporal evolution of such faults. In particular, we formulate the coupling between temperature and pressure evolution in the faults through their multiphysics energetic process(es. We analyse their multiple steady states using numerical continuation methods and characterise their transient dynamics by studying the time-dependent problem near the critical Hopf points. We find that the global system can be characterised by a homoclinic bifurcation that depends on the two main dimensionless groups of the underlying physical system. The Gruntfest number determines the onset of the localisation phenomenon, while the dynamics are mainly controlled by the Lewis number, which is the ratio of energy diffusion over mass diffusion. Here, we show that the Lewis number is the critical parameter for dynamics of the system as it controls the time evolution of the system for a given energy supply (Gruntfest number.

  20. Improving the capability of an integrated CA-Markov model to simulate spatio-temporal urban growth trends using an Analytical Hierarchy Process and Frequency Ratio

    Science.gov (United States)

    Aburas, Maher Milad; Ho, Yuek Ming; Ramli, Mohammad Firuz; Ash'aari, Zulfa Hanan

    2017-07-01

    The creation of an accurate simulation of future urban growth is considered one of the most important challenges in urban studies that involve spatial modeling. The purpose of this study is to improve the simulation capability of an integrated CA-Markov Chain (CA-MC) model using CA-MC based on the Analytical Hierarchy Process (AHP) and CA-MC based on Frequency Ratio (FR), both applied in Seremban, Malaysia, as well as to compare the performance and accuracy between the traditional and hybrid models. Various physical, socio-economic, utilities, and environmental criteria were used as predictors, including elevation, slope, soil texture, population density, distance to commercial area, distance to educational area, distance to residential area, distance to industrial area, distance to roads, distance to highway, distance to railway, distance to power line, distance to stream, and land cover. For calibration, three models were applied to simulate urban growth trends in 2010; the actual data of 2010 were used for model validation utilizing the Relative Operating Characteristic (ROC) and Kappa coefficient methods Consequently, future urban growth maps of 2020 and 2030 were created. The validation findings confirm that the integration of the CA-MC model with the FR model and employing the significant driving force of urban growth in the simulation process have resulted in the improved simulation capability of the CA-MC model. This study has provided a novel approach for improving the CA-MC model based on FR, which will provide powerful support to planners and decision-makers in the development of future sustainable urban planning.

  1. Simulation Apps Bring Us Closer to Mars

    Science.gov (United States)

    Knox, Jim

    2015-01-01

    My work with mathematical modeling and computer simulations began in earnest in 1987 when I signed on with the National Aeronautics and Space Administration, better known as NASA. At the time I was developing computer simulations to support the design of carbon dioxide (CO2) removal systems for the International Space Station (ISS) life support system. CO2 is a human metabolic waste, produced at a rate of a kilogram per day per crewmember. CO2 must be removed from the crew cabin, as it will quickly become detrimental to crew health. The systems used to remove CO2 are typically based on sorption processes, which include complex interactions of heat transfer, mass transfer, and gas flow through porous media. At this time, there were no commercial options for solving a set of coupled mathematical models such as partial differential equations (PDEs); you either force-fit the physics into a thermal analysis package or wrote your own code, complete with discretization, meshing, and solution algorithms. Unfortunately, coding CO2 removal processes from scratch did not allow an appropriate focus on the challenging yet crucial task of understanding and capturing the underlying physics via appropriate mathematical models. Configuration control was often simply ignored due to tight schedules, resulting in a code that would be quicker for a second party to rewrite than modify. In the early 2000s, I decided to move CO2 removal simulations to a platform with built-in meshing, solvers, and postprocessing capabilities, and that could solve user-defined multiphysics PDEs. The program chosen to meet these needs was COMSOL Multiphysics®. Along with freeing the engineer to focus on the underlying physics, a degree of configuration control was automatically achieved via a consistent user interface, thus allowing COMSOL users to share computer models. My team has developed simulations that are already providing a valuable debugging capability for the ISS CO2 removal system, and will

  2. Improving CT scan capabilities with a new trauma workflow concept: Simulation of hospital logistics using different CT scanner scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Fung Kon Jin, P.H.P., E-mail: p.fungkonjin@amc.uva.nl [Trauma Unit Department of Surgery, Academic Medical Center, Amsterdam (Netherlands); Dijkgraaf, M.G.W., E-mail: m.dijkgraaf@amc.uva.nl [Department of Clinical Epidemiology, Biostatistics, and Bioinformatics, Academic Medical Center, Amsterdam (Netherlands); Alons, C.L., E-mail: clalons@few.vu.nl [Department of Mathematics, VU University Amsterdam, Amsterdam (Netherlands); Kuijk, C. van, E-mail: c.vankuijk@vumc.nl [Department of Radiology, VU Medical Center, Amsterdam (Netherlands); Beenen, L.F.M., E-mail: l.beenen@amc.uva.nl [Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); Koole, G.M., E-mail: koole@few.vu.nl [Department of Mathematics, VU University Amsterdam, Amsterdam (Netherlands); Goslings, J.C., E-mail: j.c.goslings@amc.uva.nl [Trauma Unit Department of Surgery, Academic Medical Center, Amsterdam (Netherlands)

    2011-11-15

    Introduction: The Amsterdam Trauma Workflow (ATW) concept includes a sliding gantry CT scanner serving two mirrored (trauma) rooms. In this study, several predefined scenarios with a varying number of CT scanners and CT locations are analyzed to identify the best performing patient flow management strategy from an institutional perspective on process quality. Materials and methods: A total of six clinically relevant scenarios with variables that included the number of CT scanners, CT scanner location, and different patient categories (regular, urgent, and trauma patients) were evaluated using computer simulation. Each scenario was simulated using institutional data and was assessed for patient waiting times, idle time of CT scanners, and overtime due to scheduling. The best 2- and 3-scanner scenarios were additionally evaluated with the ATW-concept. Results: Based on institutional data, the best 2-scanner scenario distributes all 3 patient categories over both scanners and plans 4 urgent patients per hour while locating both scanners outside of the trauma room. The best 3-scanner scenario distributes urgent and regular patients over all 3 scanners and trauma patients on only 1 scanner and locates all CT scanners outside of the trauma room. The ATW concept reduces waiting times and overtime, while increasing idle time. Conclusion: Choosing the optimal planning and distribution strategies depends on the number and location of available CT scanners, along with number of trauma, urgent and regular patients. The Amsterdam Trauma Workflow concept could provide institutions with the ability of early CT scanning in trauma patients without influencing regular and urgent CT scanning.

  3. Modeling and Simulation of A Novel Autonomous Underwater Vehicle with Glider and Flapping-Foil Propulsion Capabilities

    Institute of Scientific and Technical Information of China (English)

    TIAN Wen-long; SONG Bao-wei; DU Xiao-xu; MAO Zhao-yong; DING Hao

    2012-01-01

    HAISHEN is a long-ranged and highly maneuverable AUV which has two operating modes:glider mode and flapping-foil propulsion mode.As part of the vehicle development,a three-dimensional mathematical model of the conceptual vehicle was developed on the assumption that HAISHEN has a rigid body with two independently controlled oscillating hydrofoils.A flapping-foil model was developed based on the work done by Georgiades et al.(2009).Effect of controllable hydrofoils on the vehicle stable motion performance was studied theoretically.Finally,a dynamics simulation of the vehicle in both operating modes is created in this paper.The simulation demonstrates that:(1) in the glider mode,owing to the independent control of the pitch angle of each hydrofoil,HAISHEN travels faster and more efficiently and has a smaller turning radius than conventional fix-winged gliders; (2) in the flapping-foil propulsion mode,HAISHEN has a high maneuverability with a turning radius smaller than 15 m and a forward motion velocity about 1.8 m/s; (3) the vehicle is stable under all expected operating conditions.

  4. Fully Coupled Aero-Thermochemical-Elastic Simulations of an Eroding Graphite Nozzle

    Science.gov (United States)

    Blades, E. L.; Reveles, N. D.; Nucci, M.; Maclean, M.

    2017-01-01

    A multiphysics simulation capability has been developed that incorporates mutual interactions between aerodynamics, structural response from aero/thermal loading, ablation/pyrolysis, heating, and surface-to-surface radiation to perform high-fidelity, fully coupled aerothermoelastic ablation simulations, which to date had been unattainable. The multiphysics framework couples CHAR (a 3-D implicit charring ablator solver), Loci/CHEM (a computational fluid dynamics solver for high-speed chemically reacting flows), and Abaqus (a nonlinear structural dynamics solver) to create a fully coupled aerothermoelastic charring ablative solver. The solvers are tightly coupled in a fully integrated fashion to resolve the effects of the ablation pyrolysis and charring process and chemistry products upon the flow field, the changes in surface geometry due to recession upon the flow field, and thermal-structural analysis of the body from the induced aerodynamic heating from the flow field. The multiphysics framework was successfully demonstrated on a solid rocket motor graphite nozzle erosion application. Comparisons were made with available experimental data that measured the throat erosion during the motor firing. The erosion data is well characterized, as the test rig was equipped with a windowed nozzle section for real-time X-ray radiography diagnostics of the instantaneous throat variations for deducing the instantaneous erosion rates. The nozzle initially undergoes a nozzle contraction due to thermal expansion before ablation effects are able to widen the throat. A series of parameters studies were conducted using the coupled simulation capability to determine the sensitivity of the nozzle erosion to different parameters. The parameter studies included the shape of the nozzle throat (flat versus rounded), the material properties, the effect of the choice of turbulence model, and the inclusion or exclusion of the mechanical thermal expansion. Overall, the predicted results match

  5. Numerical simulation of the role of the utriculo-endolymphatic valve in the rotation-sensing capabilities of semicircular canals.

    Science.gov (United States)

    Shen, Shuang; Sun, Xiuzhen; Yu, Shen; Liu, Yingxi; Su, Yingfeng; Zhao, Wei; Liu, Wenlong

    2016-06-14

    The utriculo-endolymphatic valve (UEV) has an uncertain function, but its opening and closure have been predicted to maintain a constant endolymphatic pressure within the semicircular canals (SCCs) and the utricle of the inner ear. Here, the study׳s aim was to examine the role of the UEV in regulating the capabilities of the 3 SCCs in sensing angular acceleration by using the finite element method. The results of the developed model showed endolymphatic flow and cupula displacement patterns in good agreement with previous experiments. Moreover, the open valve was predicted to permit endolymph exchange between the 2 parts of the membranous labyrinth during head rotation and, in comparison to the closed valve, to result in a reinforced endolymph flow in the utricle and an enhanced or weakened cupula deflection. Further, the model predicted an increase in the size of the orifice would result in greater endolymph exchange and thereby to a greater impact on cupula deflection. The model findings suggest the UEV plays a crucial role in the preservation of inner ear sensory function.

  6. Dynamic capabilities

    DEFF Research Database (Denmark)

    Grünbaum, Niels Nolsøe; Stenger, Marianne

    2013-01-01

    it was dominated by a lack of systematism, assessment, monitoring, marketing speculations and feasibility calculation. Furthermore, the sphere was dictated by asymmetric supplier-customer relationships and negotiation power leading, among other possible factors, to meager profitability.......The consequences of dynamic capabilities (i.e. innovation performance and profitability) is an under researched area in the growing body of literature on dynamic capabilities and innovation management. This study aims to examine the relationship between dynamic capabilities, innovation performance...... and profitability of small and medium sized manufacturing enterprises operating in volatile environments. A multi-case study design was adopted as research strategy. The findings reveal a positive relationship between dynamic capabilities and innovation performance in the case companies, as we would expect. It was...

  7. Simulations of the x-ray imaging capabilities of the silicon drift detectors (SDD) for the LOFT wide-field monitor

    DEFF Research Database (Denmark)

    Evangelista, Y.; Campana, R.; Del Monte, E.

    2012-01-01

    Detector (LAD), carrying an unprecedented effective area of 10 m^2, is complemented by a coded-mask Wide Field Monitor, in charge of monitoring a large fraction of the sky potentially accessible to the LAD, to provide the history and context for the sources observed by LAD and to trigger its observations...... on their most interesting and extreme states. In this paper we present detailed simulations of the imaging capabilities of the Silicon Drift Detectors developed for the LOFT Wide Field Monitor detection plane. The simulations explore a large parameter space for both the detector design and the environmental...... conditions, allowing us to optimize the detector characteristics and demonstrating the X-ray imaging performance of the large-area SDDs in the 2-50 keV energy band....

  8. Three-dimensional multi-physics analysis and commissioning frequency tuning strategy of a radio-frequency quadrupole accelerator

    Science.gov (United States)

    Ma, Wei; Lu, Liang; Liu, Ting; Xu, Xianbo; Sun, Liepeng; Li, Chenxing; Shi, Longbo; Wang, Wenbin; He, Yuan; Zhao, Hongwei

    2017-09-01

    The resonant frequency stability of the radio frequency quadrupole (RFQ) is an important concern during commissioning. The power dissipated on the RFQ internal surface will heat the cavity and lead to a temperature rise and a structural deformation, especially in the continuous wave (CW) RFQs, which will cause the resonant frequency shifts. It is important to simulate the temperature rise, the deformation and the frequency shift of the RFQ cavity. The cooling water takes away the power to maintain the frequency stability. Meanwhile, the RFQ resonant frequency can be tuned by adjusting the water temperature. In this paper, a detailed three-dimensional multi-physics analysis of the Low Energy Accelerator Facility (LEAF) RFQ will be presented and a commissioning frequency tuning strategy will be studied.

  9. Multiphysical modelling of fluid transport through osteo-articular media

    Directory of Open Access Journals (Sweden)

    Thibault Lemaire

    2010-03-01

    Full Text Available In this study, a multiphysical description of fluid transport through osteo-articular porous media is presented. Adapted from the model of Moyne and Murad, which is intended to describe clayey materials behaviour, this multiscale modelling allows for the derivation of the macroscopic response of the tissue from microscopical information. First the model is described. At the pore scale, electrohydrodynamics equations governing the electrolyte movement are coupled with local electrostatics (Gauss-Poisson equation, and ionic transport equations. Using a change of variables and an asymptotic expansion method, the macroscopic description is carried out. Results of this model are used to show the importance of couplings effects on the mechanotransduction of compact bone remodelling.Neste estudo uma descrição multifísica do transporte de fluidos em meios porosos osteo articulares é apresentada. Adaptado a partir do modelo de Moyne e Murad proposto para descrever o comportamento de materiais argilosos a modelagem multiescala permite a derivação da resposta macroscópica do tecido a partir da informação microscópica. Na primeira parte o modelo é apresentado. Na escala do poro as equações da eletro-hidrodinâmica governantes do movimento dos eletrolitos são acopladas com a eletrostática local (equação de Gauss-Poisson e as equações de transporte iônico. Usando uma mudança de variáveis e o método de expansão assintótica a derivação macroscópica é conduzida. Resultados do modelo proposto são usados para salientar a importância dos efeitos de acoplamento sobre a transdução mecânica da remodelagem de ossos compactados.

  10. Lightweighting Automotive Materials for Increased Fuel Efficiency and Delivering Advanced Modeling and Simulation Capabilities to U.S. Manufacturers

    Energy Technology Data Exchange (ETDEWEB)

    Hale, Steve

    2013-09-11

    Abstract The National Center for Manufacturing Sciences (NCMS) worked with the U.S. Department of Energy (DOE), National Energy Technology Laboratory (NETL), to bring together research and development (R&D) collaborations to develop and accelerate the knowledgebase and infrastructure for lightweighting materials and manufacturing processes for their use in structural and applications in the automotive sector. The purpose/importance of this DOE program: • 2016 CAFÉ standards. • Automotive industry technology that shall adopt the insertion of lightweighting material concepts towards manufacturing of production vehicles. • Development and manufacture of advanced research tools for modeling and simulation (M&S) applications to reduce manufacturing and material costs. • U.S. competitiveness that will help drive the development and manufacture of the next generation of materials. NCMS established a focused portfolio of applied R&D projects utilizing lightweighting materials for manufacture into automotive structures and components. Areas that were targeted in this program: • Functionality of new lightweighting materials to meet present safety requirements. • Manufacturability using new lightweighting materials. • Cost reduction for the development and use of new lightweighting materials. The automotive industry’s future continuously evolves through innovation, and lightweight materials are key in achieving a new era of lighter, more efficient vehicles. Lightweight materials are among the technical advances needed to achieve fuel/energy efficiency and reduce carbon dioxide (CO2) emissions: • Establish design criteria methodology to identify the best materials for lightweighting. • Employ state-of-the-art design tools for optimum material development for their specific applications. • Match new manufacturing technology to production volume. • Address new process variability with new production-ready processes.

  11. Performance of multi-physics ensembles in convective precipitation events over northeastern Spain

    Science.gov (United States)

    García-Ortega, E.; Lorenzana, J.; Merino, A.; Fernández-González, S.; López, L.; Sánchez, J. L.

    2017-07-01

    Convective precipitation with hail greatly affects southwestern Europe, causing major economic losses. The local character of this meteorological phenomenon is a serious obstacle to forecasting. Therefore, the development of reliable short-term forecasts constitutes an essential challenge to minimizing and managing risks. However, deterministic outcomes are affected by different uncertainty sources, such as physics parameterizations. This study examines the performance of different combinations of physics schemes of the Weather Research and Forecasting model to describe the spatial distribution of precipitation in convective environments with hail falls. Two 30-member multi-physics ensembles, with two and three domains of maximum resolution 9 and 3km each, were designed using various combinations of cumulus, microphysics and radiation schemes. The experiment was evaluated for 10 convective precipitation days with hail over 2005-2010 in northeastern Spain. Different indexes were used to evaluate the ability of each ensemble member to capture the precipitation patterns, which were compared with observations of a rain-gauge network. A standardized metric was constructed to identify optimal performers. Results show interesting differences between the two ensembles. In two domain simulations, the selection of cumulus parameterizations was crucial, with the Betts-Miller-Janjic scheme the best. In contrast, the Kain-Fristch cumulus scheme gave the poorest results, suggesting that it should not be used in the study area. Nevertheless, in three domain simulations, the cumulus schemes used in coarser domains were not critical and the best results depended mainly on microphysics schemes. The best performance was shown by Morrison, New Thomson and Goddard microphysics.

  12. Multiphysical Modeling of Transport Phenomena During Laser Welding of Dissimilar Steels

    Science.gov (United States)

    Métais, A.; Matteï, S.; Tomashchuk, I.; Gaied, S.

    The success of new high-strength steels allows attaining equivalent performances with lower thicknesses and significant weight reduction. The welding of new couples of steel grades requires development and control of joining processes. Thanks to high precision and good flexibility, laser welding became one of the most used processes for joining of dissimilar welded blanks. The prediction of the local chemical composition in the weld formed between dissimilar steels in function of the welding parameters is essential because the dilution rate and the distribution of alloying elements in the melted zone determines the final tensile strength of the weld. The goal of the present study is to create and to validate a multiphysical numerical model studying the mixing of dissimilar steels in laser weld pool. A 3D modelling of heat transfer, turbulent flow and transport of species provides a better understanding of diffusion and convective mixing in laser weld pool. The present model allows predicting the weld geometry and element distribution. The model has been developed based on steady keyhole approximation and solved in quasi-stationary form in order to reduce the computation time. Turbulent flow formulation was applied to calculate velocity field. Fick law for diluted species was used to simulate the transport of alloying elements in the weld pool. To validate the model, a number of experiments have been performed: tests using pure 100 μm thick Ni foils like tracer and weld between a rich and poor manganese steels. SEM-EDX analysis of chemical composition has been carried out to obtain quantitative mapping of Ni and Mn distributions in the melted zone. The results of simulations have been found in good agreement with experimental data.

  13. Applying multi-physics requirements and loads in FEM analysis and testing—The JET KL11 endoscope design verification process

    Energy Technology Data Exchange (ETDEWEB)

    Zauner, C., E-mail: zauner@krp-m.de [KRP-Mechatec Engineering GbR, D-85748 Garching (Germany); Klammer, J. [KRP-Mechatec Engineering GbR, D-85748 Garching (Germany); Hartl, M.; Kampf, D. [Kayser-Threde GmbH, D-81379 Munich (Germany); Huber, A.; Mertens, Ph.; Schweer, B.; Terra, A. [Institute of Energy and Climate Research – Plasma Physics, Forschungszentrum Jülich, EURATOM Association, Trilateral Euregio Cluster, D-52425 Jülich (Germany); Balshaw, N. [Euratom-CCFE Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom)

    2013-10-15

    Considering multi-physics requirements and loads in the early design phase as well as during the later experimental verification is especially important for the design of fusion devices due to the extreme environmental conditions and loads. Typical disciplines in design of fusion devices are thermodynamics, structural-mechanics, electro-magnetics, and optics. The interaction of these disciplines as well as an efficient approach to implement this interaction in numerical and experimental simulations is presented as applied at the new JET KL11 divertor endoscope design and verification process. The endoscope's first pictures already showed the very good performance of the instrument.

  14. Capability approach

    DEFF Research Database (Denmark)

    Jensen, Niels Rosendal; Kjeldsen, Christian Christrup

    Lærebogen er den første samlede danske præsentation af den af Amartya Sen og Martha Nussbaum udviklede Capability Approach. Bogen indeholder en præsentation og diskussion af Sen og Nussbaums teoretiske platform. I bogen indgår eksempler fra såvel uddannelse/uddannelsespolitik, pædagogik og omsorg....

  15. ENTREPRENEURIAL CAPABILITIES

    DEFF Research Database (Denmark)

    Rasmussen, Lauge Baungaard; Nielsen, Thorkild

    2003-01-01

    The aim of this article is to analyse entrepreneurship from an action research perspective. What is entrepreneurship about? Which are the fundamental capabilities and processes of entrepreneurship? To answer these questions the article includes a case study of a Danish entrepreneur and his networks...

  16. The atmospheric component of the Mediterranean Sea water budget in a WRF multi-physics ensemble and observations

    Science.gov (United States)

    Di Luca, Alejandro; Flaounas, Emmanouil; Drobinski, Philippe; Brossier, Cindy Lebeaupin

    2014-11-01

    The use of high resolution atmosphere-ocean coupled regional climate models to study possible future climate changes in the Mediterranean Sea requires an accurate simulation of the atmospheric component of the water budget (i.e., evaporation, precipitation and runoff). A specific configuration of the version 3.1 of the weather research and forecasting (WRF) regional climate model was shown to systematically overestimate the Mediterranean Sea water budget mainly due to an excess of evaporation (~1,450 mm yr-1) compared with observed estimations (~1,150 mm yr-1). In this article, a 70-member multi-physics ensemble is used to try to understand the relative importance of various sub-grid scale processes in the Mediterranean Sea water budget and to evaluate its representation by comparing simulated results with observed-based estimates. The physics ensemble was constructed by performing 70 1-year long simulations using version 3.3 of the WRF model by combining six cumulus, four surface/planetary boundary layer and three radiation schemes. Results show that evaporation variability across the multi-physics ensemble (˜10 % of the mean evaporation) is dominated by the choice of the surface layer scheme that explains more than ˜70 % of the total variance and that the overestimation of evaporation in WRF simulations is generally related with an overestimation of surface exchange coefficients due to too large values of the surface roughness parameter and/or the simulation of too unstable surface conditions. Although the influence of radiation schemes on evaporation variability is small (˜13 % of the total variance), radiation schemes strongly influence exchange coefficients and vertical humidity gradients near the surface due to modifications of temperature lapse rates. The precipitation variability across the physics ensemble (˜35 % of the mean precipitation) is dominated by the choice of both cumulus (˜55 % of the total variance) and planetary boundary layer (˜32 % of

  17. Dynamic capabilities

    DEFF Research Database (Denmark)

    Grünbaum, Niels Nolsøe; Stenger, Marianne

    2013-01-01

    and profitability of small and medium sized manufacturing enterprises operating in volatile environments. A multi-case study design was adopted as research strategy. The findings reveal a positive relationship between dynamic capabilities and innovation performance in the case companies, as we would expect. It was...... it was dominated by a lack of systematism, assessment, monitoring, marketing speculations and feasibility calculation. Furthermore, the sphere was dictated by asymmetric supplier-customer relationships and negotiation power leading, among other possible factors, to meager profitability....

  18. Development of high-fidelity multiphysics system for light water reactor analysis

    Science.gov (United States)

    Magedanz, Jeffrey W.

    There has been a tendency in recent years toward greater heterogeneity in reactor cores, due to the use of mixed-oxide (MOX) fuel, burnable absorbers, and longer cycles with consequently higher fuel burnup. The resulting asymmetry of the neutron flux and energy spectrum between regions with different compositions causes a need to account for the directional dependence of the neutron flux, instead of the traditional diffusion approximation. Furthermore, the presence of both MOX and high-burnup fuel in the core increases the complexity of the heat conduction. The heat transfer properties of the fuel pellet change with irradiation, and the thermal and mechanical expansion of the pellet and cladding strongly affect the size of the gap between them, and its consequent thermal resistance. These operational tendencies require higher fidelity multi-physics modeling capabilities, and this need is addressed by the developments performed within this PhD research. The dissertation describes the development of a High-Fidelity Multi-Physics System for Light Water Reactor Analysis. It consists of three coupled codes -- CTF for Thermal Hydraulics, TORT-TD for Neutron Kinetics, and FRAPTRAN for Fuel Performance. It is meant to address these modeling challenges in three ways: (1) by resolving the state of the system at the level of each fuel pin, rather than homogenizing entire fuel assemblies, (2) by using the multi-group Discrete Ordinates method to account for the directional dependence of the neutron flux, and (3) by using a fuel-performance code, rather than a Thermal Hydraulics code's simplified fuel model, to account for the material behavior of the fuel and its feedback to the hydraulic and neutronic behavior of the system. While the first two are improvements, the third, the use of a fuel-performance code for feedback, constitutes an innovation in this PhD project. Also important to this work is the manner in which such coupling is written. While coupling involves combining

  19. 3D COMSOL Simulations for Thermal Deflection of HFIR Fuel Plate in the "Cheverton-Kelley" Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Prashant K [ORNL; Freels, James D [ORNL; Cook, David Howard [ORNL

    2012-08-01

    Three dimensional simulation capabilities are currently being developed at Oak Ridge National Laboratory using COMSOL Multiphysics, a finite element modeling software, to investigate thermal expansion of High Flux Isotope Reactor (HFIR) s low enriched uranium fuel plates. To validate simulations, 3D models have also been developed for the experimental setup used by Cheverton and Kelley in 1968 to investigate the buckling and thermal deflections of HFIR s highly enriched uranium fuel plates. Results for several simulations are presented in this report, and comparisons with the experimental data are provided when data are available. A close agreement between the simulation results and experimental findings demonstrates that the COMSOL simulations are able to capture the thermal expansion physics accurately and that COMSOL could be deployed as a predictive tool for more advanced computations at realistic HFIR conditions to study temperature-induced fuel plate deflection behavior.

  20. Multiphysics modeling of two-phase film boiling within porous corrosion deposits

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Miaomiao, E-mail: mmjin@mit.edu; Short, Michael, E-mail: hereiam@mit.edu

    2016-07-01

    Porous corrosion deposits on nuclear fuel cladding, known as CRUD, can cause multiple operational problems in light water reactors (LWRs). CRUD can cause accelerated corrosion of the fuel cladding, increase radiation fields and hence greater exposure risk to plant workers once activated, and induce a downward axial power shift causing an imbalance in core power distribution. In order to facilitate a better understanding of CRUD's effects, such as localized high cladding surface temperatures related to accelerated corrosion rates, we describe an improved, fully-coupled, multiphysics model to simulate heat transfer, chemical reactions and transport, and two-phase fluid flow within these deposits. Our new model features a reformed assumption of 2D, two-phase film boiling within the CRUD, correcting earlier models' assumptions of single-phase coolant flow with wick boiling under high heat fluxes. This model helps to better explain observed experimental values of the effective CRUD thermal conductivity. Finally, we propose a more complete set of boiling regimes, or a more detailed mechanism, to explain recent CRUD deposition experiments by suggesting the new concept of double dryout specifically in thick porous media with boiling chimneys. - Highlights: • A two-phase model of CRUD's effects on fuel cladding is developed and improved. • This model eliminates the formerly erroneous assumption of wick boiling. • Higher fuel cladding temperatures are predicted when accounting for two-phase flow. • Double-peaks in thermal conductivity vs. heat flux in experiments are explained. • A “double dryout” mechanism in CRUD is proposed based on the model and experiments.

  1. A Multiphysics Framework to Learn and Predict in Presence of Multiple Scales

    Science.gov (United States)

    Tomin, P.; Lunati, I.

    2015-12-01

    Modeling complex phenomena in the subsurface remains challenging due to the presence of multiple interacting scales, which can make it impossible to focus on purely macroscopic phenomena (relevant in most applications) and neglect the processes at the micro-scale. We present and discuss a general framework that allows us to deal with the situation in which the lack of scale separation requires the combined use of different descriptions at different scale (for instance, a pore-scale description at the micro-scale and a Darcy-like description at the macro-scale) [1,2]. The method is based on conservation principles and constructs the macro-scale problem by numerical averaging of micro-scale balance equations. By employing spatiotemporal adaptive strategies, this approach can efficiently solve large-scale problems [2,3]. In addition, being based on a numerical volume-averaging paradigm, it offers a tool to illuminate how macroscopic equations emerge from microscopic processes, to better understand the meaning of microscopic quantities, and to investigate the validity of the assumptions routinely used to construct the macro-scale problems. [1] Tomin, P., and I. Lunati, A Hybrid Multiscale Method for Two-Phase Flow in Porous Media, Journal of Computational Physics, 250, 293-307, 2013 [2] Tomin, P., and I. Lunati, Local-global splitting and spatiotemporal-adaptive Multiscale Finite Volume Method, Journal of Computational Physics, 280, 214-231, 2015 [3] Tomin, P., and I. Lunati, Spatiotemporal adaptive multiphysics simulations of drainage-imbibition cycles, Computational Geosciences, 2015 (under review)

  2. Electromagnetic Simulation Seminar and Opera/Tosca update Seminar

    CERN Multimedia

    IT Department

    2012-01-01

    9 May 2012 Kjell Johnsen Auditorium – Room 30-7-018 Electromagnetic Simulation Seminar & Opera/Tosca update Seminar By Cobham Technical Services – Vector Fields Software Virtual prototyping using electromagnetic simulation software plays an important role in the design stage of many devices and the Opera software has been in use for this purpose at CERN for over a decade. A technical seminar will take place concerning the latest developments in electromagnetic design, analysis and multi-physics applications for large scientific experiments.  Information will be presented on applications such as superconducting magnets and ion-beam sources. The seminar will be presented by engineers/physicists from Cobham Technical Services – Vector Fields Software who develop the Opera program.  It is FREE to attend and is open to both current Opera software users and also those who wish to expand their knowledge and understand better the capabilities on offer. Prog...

  3. The capability of trapping gaseous microemboli of two pediatric arterial filters with pulsatile and nonpulsatile flow in a simulated infant CPB model.

    Science.gov (United States)

    Wang, Shigang; Win, Khin N; Kunselman, Allen R; Woitas, Karl; Myers, John L; Undar, Akif

    2008-01-01

    The study objective was to test the capability of Medtronic Affinity and Terumo Capiox pediatric arterial filters to trap gaseous microemboli in a simulated infant cardiopulmonary bypass (CPB) model. The filters were used in parallel pattern. The circuit was primed with lactated ringer's solution (700 ml) and postfilter pressure was maintained at 100 mm Hg using a Hoffman clamp. Trials were conducted at flow rates ranging from 500 to 1,250 ml/min. After introducing 20 ml air into the venous line via an 18-G needle, 2-minute segments of data were recorded. This entire process was repeated 6 times for each unique combination of arterial filter, flow rate and perfusion mode, yielding a total of 96 experiments. More than 80% of gaseous microemboli were trapped by the two pediatric arterial filters. With increased flow rates and pulsatile mode, more gaseous microemboli passed through the arterial filters. There were no differences in terms of the percentage of gaseous microemboli trapped and pressure drops between Medtronic Affinity and Terumo Capiox pediatric arterial filters. Results demonstrated that Medtronic Affinity and Terumo Capiox pediatric arterial filters could trap the majority of gaseous microemboli in this particular setting of an open arterial filter purge line in a simulated infant CPB circuit with pulsatile and nonpulsatile flow.

  4. Capability of a regional climate model to simulate climate variables requested for water balance computation: a case study over northeastern France

    Science.gov (United States)

    Boulard, Damien; Castel, Thierry; Camberlin, Pierre; Sergent, Anne-Sophie; Bréda, Nathalie; Badeau, Vincent; Rossi, Aurélien; Pohl, Benjamin

    2016-05-01

    This paper documents the capability of the ARW/WRF regional climate model to regionalize near-surface atmospheric variables at high resolution (8 km) over Burgundy (northeastern France) from daily to interannual timescales. To that purpose, a 20-year continuous simulation (1989-2008) was carried out. The WRF model driven by ERA-Interim reanalyses was compared to in situ observations and a mesoscale atmospheric analyses system (SAFRAN) for five near-surface variables: precipitation, air temperature, wind speed, relative humidity and solar radiation, the last four variables being used for the calculation of potential evapotranspiration (ET0). Results show a significant improvement upon ERA-Interim. This is due to a good skill of the model to reproduce the spatial distribution for all weather variables, in spite of a slight over-estimation of precipitation amounts mostly during the summer convective season, and wind speed during winter. As compared to the Météo-France observations, WRF also improves upon SAFRAN analyses, which partly fail at showing realistic spatial distributions for wind speed, relative humidity and solar radiation—the latter being strongly underestimated. The SAFRAN ET0 is thus highly under-estimated too. WRF ET0 is in better agreement with observations. In order to evaluate WRF's capability to simulate a reliable ET0, the water balance of thirty Douglas-fir stands was computed using a process-based model. Three soil water deficit indexes corresponding to the sum of the daily deviations between the relative extractible water and a critical value of 40 % below which the low soil water content affects tree growth, were calculated using the nearest weather station, SAFRAN analyses weather data, or by merging observation and WRF weather variables. Correlations between Douglas-fir growth and the three estimated soil water deficit indexes show similar results. These results showed through the ET0 estimation and the relation between mean annual SWDI

  5. Adjoint sensitivity in PDE constrained least squares problems as a multiphysics problem

    NARCIS (Netherlands)

    Lahaye, D.; Mulckhuyse, W.F.W.

    2012-01-01

    Purpose - The purpose of this paper is to provide a framework for the implementation of an adjoint sensitivity formulation for least-squares partial differential equations constrained optimization problems exploiting a multiphysics finite elements package. The estimation of the diffusion coefficient

  6. ACME algorithms for contact in a multiphysics environment API version 2.2.

    Energy Technology Data Exchange (ETDEWEB)

    Heinstein, Martin Wilhelm; Glass, Micheal W.; Gullerud, Arne S.; Brown, Kevin H.; Voth, Thomas Eugene; Jones, Reese E.

    2004-07-01

    An effort is underway at Sandia National Laboratories to develop a library of algorithms to search for potential interactions between surfaces represented by analytic and discretized topological entities. This effort is also developing algorithms to determine forces due to these interactions for transient dynamics applications. This document describes the Application Programming Interface (API) for the ACME (Algorithms for Contact in a Multiphysics Environment) library.

  7. Multiphysics Modeling of a Novel Photoelastic Modulator for Ultra-High Performance FT Spectrometry

    Science.gov (United States)

    2008-12-01

    1 MULTIPHYSICS MODELING OF A NOVEL PHOTOELASTIC MODULATOR FOR ULTRA-HIGH PERFORMANCE FT SPECTROMETRY Tudor N. Buican* Semiotic Engineering...NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Semiotic

  8. Multiphysics Analysis of the 2.5 MeV BNCT RFQ Accelerator

    CERN Document Server

    Xiaowen, Zhu; Kun, Zhu

    2016-01-01

    Boron Neutron Capture Therapy (BNCT), is an advanced cancer therapy that destroys the cancer tumors using the well-known Li(p,n)Be . Because of the highly selectively reaction between a boron and a neutron, BNCT is effective for rapidly spreading cancer, invasive carcinoma, such as head and neck cancer, melanoma, malignant brain tumors and so on. The PKU RFQ group proposes an RFQ based neutron source for BNCT application. The 162.5 MHz four-vane RFQ will accelerate 20-mA H+ from 35.0 keV to 2.50 MeV in CW mode, and delivers a neutron yield of 1.73*10^13 n/sec/cm^2. The thermal management will become the most important issues. The detailed multiphysics analysis of the BNCT RFQ will be studied, and the RFQ frequency shift during nominal operating condition is also predicted. The multiphysics analysis is performed by using the CST Multiphysics Model and verified with ANSYS Multiphysics.

  9. Three Dimensional Thermal Modeling of Li-Ion Battery Pack Based on Multiphysics and Calorimetric Measurement

    DEFF Research Database (Denmark)

    Khan, Mohammad Rezwan; Kær, Søren Knudsen

    2016-01-01

    A three-dimensional multiphysics-based thermal model of a battery pack is presented. The model is intended to demonstrate the cooling mechanism inside the battery pack. Heat transfer (HT) and computational fluid dynamics (CFD) physics are coupled for both time-dependent and steady-state simulatio...

  10. Design of an Experimental Setup for Testing Multiphysical Effects on High Speed Mini Rotors

    NARCIS (Netherlands)

    Dikmen, Emre; Hoogt, van der Peter J.M.; Boer, de André; Aarts, Ronald G.K.M.; Jonker, Ben

    2011-01-01

    Recently, there have been numerous research projects on the development of minirotating machines. These machines mostly operate at speeds above the first critical speed and have special levitation systems. Besides, the multiphysical effects become significant in small scale. Therefore, advanced mode

  11. Influence of Multiphysical Effects on the Dynamics of High Speed Minirotors—Part I: Theory

    NARCIS (Netherlands)

    Dikmen, Emre; Hoogt, van der Peter J.M.; Boer, de André; Aarts, Ronald G.K.M.

    2010-01-01

    In this study, a modeling approach has been developed to take multiphysical effects into account in the prediction of the rotordynamic behavior of high speed minirotating machinery with a moderate flow confinement. The temperature increase in the confinement and the flow induced forces resulting fro

  12. Assessment of a Hybrid Continuous/Discontinuous Galerkin Finite Element Code for Geothermal Reservoir Simulations

    Science.gov (United States)

    Xia, Yidong; Podgorney, Robert; Huang, Hai

    2017-03-01

    FALCON (Fracturing And Liquid CONvection) is a hybrid continuous/discontinuous Galerkin finite element geothermal reservoir simulation code based on the MOOSE (Multiphysics Object-Oriented Simulation Environment) framework being developed and used for multiphysics applications. In the present work, a suite of verification and validation (V&V) test problems for FALCON was defined to meet the design requirements, and solved to the interests of enhanced geothermal system modeling and simulation. The intent for this test problem suite is to provide baseline comparison data that demonstrates the performance of FALCON solution methods. The test problems vary in complexity from a single mechanical or thermal process, to coupled thermo-hydro-mechanical processes in geological porous medium. Numerical results obtained by FALCON agreed well with either the available analytical solutions or experimental data, indicating the verified and validated implementation of these capabilities in FALCON. Whenever possible, some form of solution verification has been attempted to identify sensitivities in the solution methods, and suggest best practices when using the FALCON code.

  13. Updates to the Generation of Physics Data Inputs for MAMMOTH Simulations of the Transient Reactor Test Facility - FY2016

    Energy Technology Data Exchange (ETDEWEB)

    Ortensi, Javier [Idaho National Lab. (INL), Idaho Falls, ID (United States); Baker, Benjamin Allen [Idaho National Lab. (INL), Idaho Falls, ID (United States); Schunert, Sebastian [Idaho National Lab. (INL), Idaho Falls, ID (United States); Wang, Yaqi [Idaho National Lab. (INL), Idaho Falls, ID (United States); Gleicher, Frederick Nathan [Idaho National Lab. (INL), Idaho Falls, ID (United States); DeHart, Mark David [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-06-01

    The INL is currently evolving the modeling and simulation (M&S) capability that will enable improved core operation as well as design and analysis of TREAT experiments. This M&S capability primarily uses MAMMOTH, a reactor physics application being developed under Multi-physics Object Oriented Simulation Environment (MOOSE) framework. MAMMOTH allows the coupling of a number of other MOOSE-based applications. This second year of work has been devoted to the generation of a deterministic reference solution for the full core, the preparation of anisotropic diffusion coefficients, the testing of the SPH equivalence method, and the improvement of the control rod modeling. In addition, this report includes the progress made in the modeling of the M8 core configuration and experiment vehicle since January of this year.

  14. Design and Analysis of a New Hair Sensor for Multi-Physical Signal Measurement.

    Science.gov (United States)

    Yang, Bo; Hu, Di; Wu, Lei

    2016-07-08

    A new hair sensor for multi-physical signal measurements, including acceleration, angular velocity and air flow, is presented in this paper. The entire structure consists of a hair post, a torsional frame and a resonant signal transducer. The hair post is utilized to sense and deliver the physical signals of the acceleration and the air flow rate. The physical signals are converted into frequency signals by the resonant transducer. The structure is optimized through finite element analysis. The simulation results demonstrate that the hair sensor has a frequency of 240 Hz in the first mode for the acceleration or the air flow sense, 3115 Hz in the third and fourth modes for the resonant conversion, and 3467 Hz in the fifth and sixth modes for the angular velocity transformation, respectively. All the above frequencies present in a reasonable modal distribution and are separated from interference modes. The input-output analysis of the new hair sensor demonstrates that the scale factor of the acceleration is 12.35 Hz/g, the scale factor of the angular velocity is 0.404 nm/deg/s and the sensitivity of the air flow is 1.075 Hz/(m/s)², which verifies the multifunction sensitive characteristics of the hair sensor. Besides, the structural optimization of the hair post is used to improve the sensitivity of the air flow rate and the acceleration. The analysis results illustrate that the hollow circular hair post can increase the sensitivity of the air flow and the II-shape hair post can increase the sensitivity of the acceleration. Moreover, the thermal analysis confirms the scheme of the frequency difference for the resonant transducer can prominently eliminate the temperature influences on the measurement accuracy. The air flow analysis indicates that the surface area increase of hair post is significantly beneficial for the efficiency improvement of the signal transmission. In summary, the structure of the new hair sensor is proved to be feasible by comprehensive

  15. Design and Analysis of a New Hair Sensor for Multi-Physical Signal Measurement

    Directory of Open Access Journals (Sweden)

    Bo Yang

    2016-07-01

    Full Text Available A new hair sensor for multi-physical signal measurements, including acceleration, angular velocity and air flow, is presented in this paper. The entire structure consists of a hair post, a torsional frame and a resonant signal transducer. The hair post is utilized to sense and deliver the physical signals of the acceleration and the air flow rate. The physical signals are converted into frequency signals by the resonant transducer. The structure is optimized through finite element analysis. The simulation results demonstrate that the hair sensor has a frequency of 240 Hz in the first mode for the acceleration or the air flow sense, 3115 Hz in the third and fourth modes for the resonant conversion, and 3467 Hz in the fifth and sixth modes for the angular velocity transformation, respectively. All the above frequencies present in a reasonable modal distribution and are separated from interference modes. The input-output analysis of the new hair sensor demonstrates that the scale factor of the acceleration is 12.35 Hz/g, the scale factor of the angular velocity is 0.404 nm/deg/s and the sensitivity of the air flow is 1.075 Hz/(m/s2, which verifies the multifunction sensitive characteristics of the hair sensor. Besides, the structural optimization of the hair post is used to improve the sensitivity of the air flow rate and the acceleration. The analysis results illustrate that the hollow circular hair post can increase the sensitivity of the air flow and the II-shape hair post can increase the sensitivity of the acceleration. Moreover, the thermal analysis confirms the scheme of the frequency difference for the resonant transducer can prominently eliminate the temperature influences on the measurement accuracy. The air flow analysis indicates that the surface area increase of hair post is significantly beneficial for the efficiency improvement of the signal transmission. In summary, the structure of the new hair sensor is proved to be feasible by

  16. Multiscale time-splitting strategy for multiscale multiphysics processes of two-phase flow in fractured media

    KAUST Repository

    Sun, S.

    2011-01-01

    The temporal discretization scheme is one important ingredient of efficient simulator for two-phase flow in the fractured porous media. The application of single-scale temporal scheme is restricted by the rapid changes of the pressure and saturation in the fractured system with capillarity. In this paper, we propose a multi-scale time splitting strategy to simulate multi-scale multi-physics processes of two-phase flow in fractured porous media. We use the multi-scale time schemes for both the pressure and saturation equations; that is, a large time-step size is employed for the matrix domain, along with a small time-step size being applied in the fractures. The total time interval is partitioned into four temporal levels: the first level is used for the pressure in the entire domain, the second level matching rapid changes of the pressure in the fractures, the third level treating the response gap between the pressure and the saturation, and the fourth level applied for the saturation in the fractures. This method can reduce the computational cost arisen from the implicit solution of the pressure equation. Numerical examples are provided to demonstrate the efficiency of the proposed method.

  17. Numerical Stability and Accuracy of Temporally Coupled Multi-Physics Modules in Wind-Turbine CAE Tools

    Energy Technology Data Exchange (ETDEWEB)

    Gasmi, A.; Sprague, M. A.; Jonkman, J. M.; Jones, W. B.

    2013-02-01

    In this paper we examine the stability and accuracy of numerical algorithms for coupling time-dependent multi-physics modules relevant to computer-aided engineering (CAE) of wind turbines. This work is motivated by an in-progress major revision of FAST, the National Renewable Energy Laboratory's (NREL's) premier aero-elastic CAE simulation tool. We employ two simple examples as test systems, while algorithm descriptions are kept general. Coupled-system governing equations are framed in monolithic and partitioned representations as differential-algebraic equations. Explicit and implicit loose partition coupling is examined. In explicit coupling, partitions are advanced in time from known information. In implicit coupling, there is dependence on other-partition data at the next time step; coupling is accomplished through a predictor-corrector (PC) approach. Numerical time integration of coupled ordinary-differential equations (ODEs) is accomplished with one of three, fourth-order fixed-time-increment methods: Runge-Kutta (RK), Adams-Bashforth (AB), and Adams-Bashforth-Moulton (ABM). Through numerical experiments it is shown that explicit coupling can be dramatically less stable and less accurate than simulations performed with the monolithic system. However, PC implicit coupling restored stability and fourth-order accuracy for ABM; only second-order accuracy was achieved with RK integration. For systems without constraints, explicit time integration with AB and explicit loose coupling exhibited desired accuracy and stability.

  18. Multiscale Time-Splitting Strategy for Multiscale Multiphysics Processes of Two-Phase Flow in Fractured Media

    Directory of Open Access Journals (Sweden)

    Jisheng Kou

    2011-01-01

    Full Text Available The temporal discretization scheme is one important ingredient of efficient simulator for two-phase flow in the fractured porous media. The application of single-scale temporal scheme is restricted by the rapid changes of the pressure and saturation in the fractured system with capillarity. In this paper, we propose a multi-scale time splitting strategy to simulate multi-scale multi-physics processes of two-phase flow in fractured porous media. We use the multi-scale time schemes for both the pressure and saturation equations; that is, a large time-step size is employed for the matrix domain, along with a small time-step size being applied in the fractures. The total time interval is partitioned into four temporal levels: the first level is used for the pressure in the entire domain, the second level matching rapid changes of the pressure in the fractures, the third level treating the response gap between the pressure and the saturation, and the fourth level applied for the saturation in the fractures. This method can reduce the computational cost arisen from the implicit solution of the pressure equation. Numerical examples are provided to demonstrate the efficiency of the proposed method.

  19. Goos-Hänchen shifts at a resonance angle of a two-prism structure using COMSOL multiphysics

    Science.gov (United States)

    Zhang, Wenjing; Zhang, Zhiwei; Yang, Peng; Zhu, Xiang; Dai, Yifan

    2016-10-01

    We simulated and analyzed Goos-Hänchen (GH) shifts of 633 nm polarized light through a two-prism structure, consisting of a right triangle prism and an isosceles triangle prism with Kretschmann-Raether configuration, by comparing the results from COMSOL Multiphysics (CM) simulation software with that of a stationary-phase analysis (SPA). For this two-prism structure, using a gold film that of thickness 45 nm, the maximum positive GH shift, obtained using SPA at the resonance angle of 44.1°, was 354 μm. Using CM at an incident angle of 43.8°, we found the maximum positive GH shift of 9.45 μm. The results obtained using CM are in agreement with those obtained by the SPA around the resonance angle, although the enhancement effect from CM is much less than that of SPA. This is because SPA depends on the differentiation of the phase shift with respect to the incident angle, while a drastic phase shift occurs at the resonance angle. These results are useful for designing high-sensitivity SPR sensors based on GH shift measurement and for application in waveguide-type SPR devices, with sizes in the order of micro millimeter.

  20. Parallel Monte Carlo transport modeling in the context of a time-dependent, three-dimensional multi-physics code

    Energy Technology Data Exchange (ETDEWEB)

    Procassini, R.J. [Lawrence Livermore National lab., CA (United States)

    1997-12-31

    The fine-scale, multi-space resolution that is envisioned for accurate simulations of complex weapons systems in three spatial dimensions implies flop-rate and memory-storage requirements that will only be obtained in the near future through the use of parallel computational techniques. Since the Monte Carlo transport models in these simulations usually stress both of these computational resources, they are prime candidates for parallelization. The MONACO Monte Carlo transport package, which is currently under development at LLNL, will utilize two types of parallelism within the context of a multi-physics design code: decomposition of the spatial domain across processors (spatial parallelism) and distribution of particles in a given spatial subdomain across additional processors (particle parallelism). This implementation of the package will utilize explicit data communication between domains (message passing). Such a parallel implementation of a Monte Carlo transport model will result in non-deterministic communication patterns. The communication of particles between subdomains during a Monte Carlo time step may require a significant level of effort to achieve a high parallel efficiency.

  1. Multi-physics modelling of a compliant humanoid robot

    Energy Technology Data Exchange (ETDEWEB)

    Zobova, Alexandra A., E-mail: azobova@mech.math.msu.su [Lomonosov Moscow State University, Faculty of Mechanics and Mathematics (Russian Federation); Habra, Timothée, E-mail: timothee.habra@uclouvain.be [Université catholique de Louvain (UCL), Center for Research in Mechatronics, Institute of Mechanics, Materials, and Civil Engineering (Belgium); Van der Noot, Nicolas, E-mail: nicolas.vandernoot@uclouvain.be, E-mail: nicolas.vandernoot@epfl.ch [EPFL STI IBI BIOROB, Biorobotics Laboratory, Institute of Bioengineering, École polytechnique fédérale de Lausanne (EPFL) (Switzerland); Dallali, Houman, E-mail: houman.dallali@iit.it; Tsagarakis, Nikolaos G., E-mail: nikos.tsagarakis@iit.it [Istituto Italiano di Tecnologia, Department of Advanced Robotics (Italy); Fisette, Paul, E-mail: paul.fisette@uclouvain.be; Ronsse, Renaud, E-mail: renaud.ronsse@uclouvain.be [Université catholique de Louvain (UCL), Center for Research in Mechatronics, Institute of Mechanics, Materials, and Civil Engineering (Belgium)

    2017-01-15

    We present a multibody simulator being used for compliant humanoid robot modelling and report our reasoning for choosing the settings of the simulator’s key features. First, we provide a study on how the numerical integration speed and accuracy depend on the coordinate representation of the multibody system. This choice is particularly critical for mechanisms with long serial chains (e.g. legs and arms). Our second contribution is a full electromechanical model of the inner dynamics of the compliant actuators embedded in the COMAN robot, since joints’ compliance is needed for the robot safety and energy efficiency. Third, we discuss the different approaches for modelling contacts and selecting an appropriate contact library. The recommended solution is to couple our simulator with an open-source contact library offering both accurate and fast contact modelling. The simulator performances are assessed by two different tasks involving contacts: a bimanual manipulation task and a squatting tasks. The former shows reliability of the simulator. For the latter, we report a comparison between the robot behaviour as predicted by our simulation environment, and the real one.

  2. Integration of the DRAGON5/DONJON5 codes in the SALOME platform for performing multi-physics calculations in nuclear engineering

    Science.gov (United States)

    Hébert, Alain

    2014-06-01

    We are presenting the computer science techniques involved in the integration of codes DRAGON5 and DONJON5 in the SALOME platform. This integration brings new capabilities in designing multi-physics computational schemes, with the possibility to couple our reactor physics codes with thermal-hydraulics or thermo-mechanics codes from other organizations. A demonstration is presented where two code components are coupled using the YACS module of SALOME, based on the CORBA protocol. The first component is a full-core 3D steady-state neuronic calculation in a PWR performed using DONJON5. The second component implement a set of 1D thermal-hydraulics calculations, each performed over a single assembly.

  3. The cell method for electrical engineering and multiphysics problems an introduction

    CERN Document Server

    Alotto, Piergiorgio; Repetto, Maurizio; Rosso, Carlo

    2013-01-01

    This book presents a numerical scheme for the solution of field problems governed by partial differential equations: the cell method. The technique lends itself naturally to the solution of multiphysics problems with several interacting phenomena. The Cell Method, based on a space-time tessellation, is intimately related to the work of Tonti and to his ideas of classification diagrams or, as they are nowadays called, Tonti diagrams: a graphical representation of the problem's equations made possible by a suitable selection of a space-time framework relating physical variables to each other. The main features of the cell method are presented and links with many other discrete numerical methods (finite integration techniques, finite difference time domain, finite volumes, mimetic finite differences, etc.) are discussed. After outlining the theoretical basis of the method, a set of physical problems which have been solved with the cell method is described. These single and multiphysics problems stem from the aut...

  4. A multiscale-multiphysics strategy for numerical modeling of thin piezoelectric sheets

    CERN Document Server

    Maruccio, Claudio; Persano, Luana; Pisignano, Dario

    2014-01-01

    Flexible piezoelectric devices made of polymeric materials are widely used for micro- and nano-electro-mechanical systems. In particular, numerous recent applications concern energy harvesting. Due to the importance of computational modeling to understand the influence that microscale geometry and constitutive variables exert on the macroscopic behavior, a numerical approach is developed here for multiscale and multiphysics modeling of piezoelectric materials made of aligned arrays of polymeric nanofibers. At the microscale, the representative volume element consists in piezoelectric polymeric nanofibers, assumed to feature a linear piezoelastic constitutive behavior and subjected to electromechanical contact constraints using the penalty method. To avoid the drawbacks associated with the non-smooth discretization of the master surface, a contact smoothing approach based on B\\'ezier patches is extended to the multiphysics framework providing an improved continuity of the parameterization. The contact element ...

  5. Multiphysics Analysis of Frequency Detuning in Superconducting RF Cavities for Proton Particle Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Awida, M. H. [Fermilab; Gonin, I. [Fermilab; Passarelli, D. [Fermilab; Sukanov, A. [Fermilab; Khabiboulline, T. [Fermilab; Yakovlev, V. [Fermilab

    2016-01-22

    Multiphysics analyses for superconducting cavities are essential in the course of cavity design to meet stringent requirements on cavity frequency detuning. Superconducting RF cavities are the core accelerating elements in modern particle accelerators whether it is proton or electron machine, as they offer extremely high quality factors thus reducing the RF losses per cavity. However, the superior quality factor comes with the challenge of controlling the resonance frequency of the cavity within few tens of hertz bandwidth. In this paper, we investigate how the multiphysics analysis plays a major role in proactively minimizing sources of frequency detuning, specifically; microphonics and Lorentz Force Detuning (LFD) in the stage of RF design of the cavity and mechanical design of the niobium shell and the helium vessel.

  6. Probabilistic Design and Management of Sustainable Concrete Infrastructure Using Multi-Physics Service Life Models

    DEFF Research Database (Denmark)

    Lepech, Michael; Geiker, Mette; Michel, Alexander

    cycles in the broader architecture, engineering, construction (AEC) industry. Specifically, a probabilistic design framework for sustainable concrete infrastructure and a multi-physics service life model for reinforced concrete are presented as important points of integration for innovation between...... design, consists of concrete service life models and life cycle assessment (LCA) models. Both types of models (service life and LCA) are formulated stochastically so that the service life and time(s) to repair, as well as total sustainability impact, are described by a probability distribution. A central...... component of this framework is a newly developed multi-physics service life model of reinforced concrete members subjected to chloride-induced corrosion. The corrosion model is based on stringent physical laws describing thermodynamics and kinetics of electrochemical processes including various...

  7. Multiphysics design optimization for aerospace applications: Case study on helicopter loading hanger

    Science.gov (United States)

    Xue, Hui; Khawaja, H.; Moatamedi, M.

    2014-12-01

    This paper presents the Multiphysics technique applied in the design optimization of a loading hanger for an aerial crane. In this study, design optimization is applied on the geometric modelling of a part being used in an aerial crane operation. A set of dimensional and loading requirements are provided. Various geometric models are built using SolidWorks® Computer Aided Design (CAD) Package. In addition, Finite Element Method (FEM) is applied to study these geometric models using ANSYS® Multiphysics package. Appropriate material is chosen based on the strength to weight ratio. Efforts are made to optimize the geometry to reduce the weight of the part. Based on the achieved results, conclusions are drawn.

  8. A multi-physical model of actuation response in dielectric gels

    Science.gov (United States)

    Li, Bo; Chang, LongFei; Asaka, Kinji; Chen, Hualing; Li, Dichen

    2016-12-01

    Actuation deformation of a dielectric gel is attributed to: the solvent diffusion, the electrical polarization and material hyperelasticity. A multi-physical model, coupling electrical and mechanical quantities, is established, based on the thermodynamics. A set of constitutive relations is derived as an equation of state for characterization. The model is applied to specific cases as effective validations. Physical and chemical parameters affect the performance of the gel, showing nonlinear deformation and instability. This model offers guidance for engineering application.

  9. State-of-the-Art Multi-Objective Optimisation of Manufacturing Processes Based on Thermo-Mechanical Simulations

    DEFF Research Database (Denmark)

    Tutum, Cem Celal; Hattel, Jesper Henri

    2011-01-01

    competition between manufacturers of products in combination with the possibility of doing these highly complex simulations. Thus, there is a crucial need for combining advanced simulation tools for manufacturing processes with systematic optimisation algorithms which are capable of searching for single......During the last couple of decades the possibility of modelling multi-physics phenomena has increased dramatically, thus making simulation of very complex manufacturing processes possible and in some fields even an everyday event. A consequence of this has been improved products with respect....... These limitations eventually determine what is in fact possible today and hence define what the “state-of-the-art” is. So, seen from that perspective the very definition of the state-of-the-art itself in the field of optimisation of manufacturing processes constitutes an important discussion. Moreover, in the major...

  10. Design and simulation of superconducting Lorentz Force Electrical Impedance Tomography (LFEIT)

    Science.gov (United States)

    Shen, Boyang; Fu, Lin; Geng, Jianzhao; Zhang, Xiuchang; Zhang, Heng; Dong, Qihuan; Li, Chao; Li, Jing; Coombs, T. A.

    2016-05-01

    Lorentz Force Electrical Impedance Tomography (LFEIT) is a hybrid diagnostic scanner with strong capability for biological imaging, particularly in cancer and haemorrhages detection. This paper presents the design and simulation of a novel combination: a superconducting magnet together with LFEIT system. Superconducting magnets can generate magnetic field with high intensity and homogeneity, which could significantly enhance the imaging performance. The modelling of superconducting magnets was carried out using Finite Element Method (FEM) package, COMSOL Multiphysics, which was based on Partial Differential Equation (PDE) model with H-formulation coupling B-dependent critical current density and bulk approximation. The mathematical model for LFEIT system was built based on the theory of magneto-acoustic effect. The magnetic field properties from magnet design were imported into the LFEIT model. The basic imaging of electrical signal was developed using MATLAB codes. The LFEIT model simulated two samples located in three different magnetic fields with varying magnetic strength and homogeneity.

  11. Multi-physics Coupling of Hydraulic System%液压系统多场耦合

    Institute of Scientific and Technical Information of China (English)

    张健; 罗念宁; 姜继海

    2013-01-01

    概述了液压系统多物理场耦合问题,介绍了各种耦合关系的分类方法以及液压系统中所涉及的主要物理场,并介绍了液压系统多场耦合问题的国内外研究现状.针对液压系统中常见的热、气穴、压力与流量脉动问题,分析了这些常见问题主要受到了哪些物理场的影响,并简要介绍了这些问题中存在的多物理场耦合现象,对这些问题的研究趋势进行了预测,指出在日后的研究工作中应建立多场耦合问题数学模型.最后提出了针对液压系统多场耦合特性的研究方法.%In this paper,a summary of multi-physics coupling of hydraulic system is given.The paper introduces the taxonomy of various coupling relationship and the mainly physics fields in the hydraulic system.And this paper introduces a summary of multi-physics coupling of hydraulic system both within China and abroad.According to some common problems of thermal,cavitation,pressure ripple and flow ripple on hydraulic system,this paper analyzes which fields influence on these problems,and briefly introduces the existing multi-physics coupling phenomena of problems.This paper predicts the research trend of these problems,and points out that the mathematical model of multi-physics coupling needs to be established in the future research work.studies on the mainly physics fields are involved in hydraulic system when these problems influence hydraulic system.Finally,this paper puts forward the research method of multi-physics coupling of hydraulic system.

  12. Multiphysics Numerical Modeling of a Fin and Tube Heat Exchanger

    DEFF Research Database (Denmark)

    Singh, Shobhana; Sørensen, Kim; Condra, Thomas Joseph

    2015-01-01

    ). For the purposes here, only gas flowing over the fin side is simulated assuming constant inner tube wall temperature. The study couples conjugate heat transfer mechanism with turbulent flow in order to describe the temperature and velocity profile. In addition, performance characteristics of the heat exchanger...... design in terms of heat transfer and pressure loss are determined by parameters such as overall heat transfer coefficient, Colburn j-factor, flow resistance factor, and efficiency index. The model provides useful insights necessary for optimization of heat exchanger design....

  13. Computational physics and applied mathematics capability review June 8-10, 2010

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Stephen R [Los Alamos National Laboratory

    2010-01-01

    Los Alamos National Laboratory will review its Computational Physics and Applied Mathematics (CPAM) capabilities in 2010. The goals of capability reviews are to assess the quality of science, technology, and engineering (STE) performed by the capability, evaluate the integration of this capability across the Laboratory and within the scientific community, examine the relevance of this capability to the Laboratory's programs, and provide advice on the current and future directions of this capability. This is the first such review for CPAM, which has a long and unique history at the Laboratory, starting from the inception of the Laboratory in 1943. The CPAM capability covers an extremely broad technical area at Los Alamos, encompassing a wide array of disciplines, research topics, and organizations. A vast array of technical disciplines and activities are included in this capability, from general numerical modeling, to coupled multi-physics simulations, to detailed domain science activities in mathematics, methods, and algorithms. The CPAM capability involves over 12 different technical divisions and a majority of our programmatic and scientific activities. To make this large scope tractable, the CPAM capability is broken into the following six technical 'themes.' These themes represent technical slices through the CPAM capability and collect critical core competencies of the Laboratory, each of which contributes to the capability (and each of which is divided into multiple additional elements in the detailed descriptions of the themes in subsequent sections), as follows. Theme 1: Computational Fluid Dynamics - This theme speaks to the vast array of scientific capabilities for the simulation of fluids under shocks, low-speed flow, and turbulent conditions - which are key, historical, and fundamental strengths of the Laboratory. Theme 2: Partial Differential Equations - The technical scope of this theme is the applied mathematics and numerical solution

  14. Computational Approaches for Modeling the Multiphysics in Pultrusion Process

    DEFF Research Database (Denmark)

    Carlone, P.; Baran, Ismet; Hattel, Jesper Henri;

    2013-01-01

    Pultrusion is a continuousmanufacturing process used to produce high strength composite profiles with constant cross section.The mutual interactions between heat transfer, resin flow and cure reaction, variation in the material properties, and stress/distortion evolutions strongly affect...... the process dynamics together with the mechanical properties and the geometrical precision of the final product. In the present work, pultrusion process simulations are performed for a unidirectional (UD) graphite/epoxy composite rod including several processing physics, such as fluid flow, heat transfer......, chemical reaction, and solid mechanics. The pressure increase and the resin flow at the tapered inlet of the die are calculated by means of a computational fluid dynamics (CFD) finite volume model. Several models, based on different homogenization levels and solution schemes, are proposed and compared...

  15. Concurrent, parallel, multiphysics coupling in the FACETS project

    Science.gov (United States)

    Cary, J. R.; Candy, J.; Cobb, J.; Cohen, R. H.; Epperly, T.; Estep, D. J.; Krasheninnikov, S.; Malony, A. D.; McCune, D. C.; McInnes, L.; Pankin, A.; Balay, S.; Carlsson, J. A.; Fahey, M. R.; Groebner, R. J.; Hakim, A. H.; Kruger, S. E.; Miah, M.; Pletzer, A.; Shasharina, S.; Vadlamani, S.; Wade-Stein, D.; Rognlien, T. D.; Morris, A.; Shende, S.; Hammett, G. W.; Indireshkumar, K.; Pigarov, A. Yu; Zhang, H.

    2009-07-01

    FACETS (Framework Application for Core-Edge Transport Simulations), is now in its third year. The FACETS team has developed a framework for concurrent coupling of parallel computational physics for use on Leadership Class Facilities (LCFs). In the course of the last year, FACETS has tackled many of the difficult problems of moving to parallel, integrated modeling by developing algorithms for coupled systems, extracting legacy applications as components, modifying them to run on LCFs, and improving the performance of all components. The development of FACETS abides by rigorous engineering standards, including cross platform build and test systems, with the latter covering regression, performance, and visualization. In addition, FACETS has demonstrated the ability to incorporate full turbulence computations for the highest fidelity transport computations. Early indications are that the framework, using such computations, scales to multiple tens of thousands of processors. These accomplishments were a result of an interdisciplinary collaboration among computational physics, computer scientists and applied mathematicians on the team.

  16. Design Of Piezoelectric Microcantilever Chemical Sensors In COMSOL Multiphysics Area

    Directory of Open Access Journals (Sweden)

    Maziar Norouzi

    2009-05-01

    Full Text Available This paper offers an analytical modeling ofthin-filmed, multi-layer piezoelectric microcantileversthat are used as MEMS sensors. These sensors arechemical kind and use piezoelectric microcantilever.These types of microcantilevers are covered withvariety of unique probe coating. The sensor has highsensitivity with external voltage measured in mV anduses PSD1 system to indentify chemical ingredients ofmaterials. The identification of the chemical ingredientof materials is based on change in angle of microcantilever in the liquid or gas environment. Thedeflection of microcantilever results in varying voltagethat can be used to analyze materials. Analyticalsimulation using Cosmol software and theoreticalcomputations using equations will be offered in orderto determine the parameters for optimal design setting.The analytical simulation includes design of mems andCosmol software model development. The analyticalmodel of the cantilever will be analyzed and theprocess of its construction will be discussed.

  17. Multi-physics design and analyses of long life reactors for lunar outposts

    Science.gov (United States)

    Schriener, Timothy M.

    event of a launch abort accident. Increasing the amount of fuel in the reactor core, and hence its operational life, would be possible by launching the reactor unfueled and fueling it on the Moon. Such a reactor would, thus, not be subject to launch criticality safety requirements. However, loading the reactor with fuel on the Moon presents a challenge, requiring special designs of the core and the fuel elements, which lend themselves to fueling on the lunar surface. This research investigates examples of both a solid core reactor that would be fueled at launch as well as an advanced concept which could be fueled on the Moon. Increasing the operational life of a reactor fueled at launch is exercised for the NaK-78 cooled Sectored Compact Reactor (SCoRe). A multi-physics design and analyses methodology is developed which iteratively couples together detailed Monte Carlo neutronics simulations with 3-D Computational Fluid Dynamics (CFD) and thermal-hydraulics analyses. Using this methodology the operational life of this compact, fast spectrum reactor is increased by reconfiguring the core geometry to reduce neutron leakage and parasitic absorption, for the same amount of HEU in the core, and meeting launch safety requirements. The multi-physics analyses determine the impacts of the various design changes on the reactor's neutronics and thermal-hydraulics performance. The option of increasing the operational life of a reactor by loading it on the Moon is exercised for the Pellet Bed Reactor (PeBR). The PeBR uses spherical fuel pellets and is cooled by He-Xe gas, allowing the reactor core to be loaded with fuel pellets and charged with working fluid on the lunar surface. The performed neutronics analyses ensure the PeBR design achieves a long operational life, and develops safe launch canister designs to transport the spherical fuel pellets to the lunar surface. The research also investigates loading the PeBR core with fuel pellets on the Moon using a transient Discrete

  18. Simulation based analysis of laser beam brazing

    Science.gov (United States)

    Dobler, Michael; Wiethop, Philipp; Schmid, Daniel; Schmidt, Michael

    2016-03-01

    Laser beam brazing is a well-established joining technology in car body manufacturing with main applications in the joining of divided tailgates and the joining of roof and side panels. A key advantage of laser brazed joints is the seam's visual quality which satisfies highest requirements. However, the laser beam brazing process is very complex and process dynamics are only partially understood. In order to gain deeper knowledge of the laser beam brazing process, to determine optimal process parameters and to test process variants, a transient three-dimensional simulation model of laser beam brazing is developed. This model takes into account energy input, heat transfer as well as fluid and wetting dynamics that lead to the formation of the brazing seam. A validation of the simulation model is performed by metallographic analysis and thermocouple measurements for different parameter sets of the brazing process. These results show that the multi-physical simulation model not only can be used to gain insight into the laser brazing process but also offers the possibility of process optimization in industrial applications. The model's capabilities in determining optimal process parameters are exemplarily shown for the laser power. Small deviations in the energy input can affect the brazing results significantly. Therefore, the simulation model is used to analyze the effect of the lateral laser beam position on the energy input and the resulting brazing seam.

  19. A high-fidelity multiphysics model for the new solid oxide iron-air redox battery part I: Bridging mass transport and charge transfer with redox cycle kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Jin, XF; Zhao, X; Huang, K

    2015-04-15

    A high-fidelity two-dimensional axial symmetrical multi-physics model is described in this paper as an effort to simulate the cycle performance of a recently discovered solid oxide metal-air redox battery (SOMARB). The model collectively considers mass transport, charge transfer and chemical redox cycle kinetics occurring across the components of the battery, and is validated by experimental data obtained from independent research. In particular, the redox kinetics at the energy storage unit is well represented by Johnson-Mehl-Avrami-Kolmogorov (JIVIAK) and Shrinking Core models. The results explicitly show that the reduction of Fe3O4 during the charging cycle limits the overall performance. Distributions of electrode potential, overpotential, Nernst potential, and H-2/H2O-concentration across various components of the battery are also systematically investigated. (C) 2015 Elsevier B.V. All rights reserved.

  20. Multiphysics modeling of porous CRUD deposits in nuclear reactors

    Science.gov (United States)

    Short, M. P.; Hussey, D.; Kendrick, B. K.; Besmann, T. M.; Stanek, C. R.; Yip, S.

    2013-11-01

    The formation of porous CRUD deposits on nuclear reactor fuel rods, a longstanding problem in the operation of pressurized water reactors (PWRs), is a significant challenge to science-based multiscale modeling and simulation. While existing, published studies have focused on individual or loosely coupled processes, such as heat transfer, fluid flow, and compound dissolution/precipitation, none have addressed their coupled effects sufficiently to enable a comprehensive, scientific understanding of CRUD. Here we present the formulation and results of a model, MAMBA-BDM, which begins to incorporate mechanistic details in describing CRUD in PWRs. CRUD is treated as a chemical deposition process in an environment of variable concentration, an arbitrary level of heating, and a complex fractal-based flow geometry. We present results on spatial distributions of temperature, pressure, velocity, and concentration that give insight into the interplay between these physical properties and geometrical parameters. We show the role of heat convection which has not been discussed previously. Furthermore, we suggest that the assumption of liquid saturation in the CRUD deserves scrutiny, as a result of our attempt to determine an effective CRUD thermal conductivity.

  1. Deliverable 6.2 - Software: upgraded MC simulation tools capable of simulating a complete in-beam ET experiment, from the beam to the detected events. Report with the description of one (or few) reference clinical case(s), including the complete patient model and beam characteristics

    CERN Document Server

    The ENVISION Collaboration

    2014-01-01

    Deliverable 6.2 - Software: upgraded MC simulation tools capable of simulating a complete in-beam ET experiment, from the beam to the detected events. Report with the description of one (or few) reference clinical case(s), including the complete patient model and beam characteristics

  2. Optimization of coupled multiphysics methodology for safety analysis of pebble bed modular reactor

    Science.gov (United States)

    Mkhabela, Peter Tshepo

    The research conducted within the framework of this PhD thesis is devoted to the high-fidelity multi-physics (based on neutronics/thermal-hydraulics coupling) analysis of Pebble Bed Modular Reactor (PBMR), which is a High Temperature Reactor (HTR). The Next Generation Nuclear Plant (NGNP) will be a HTR design. The core design and safety analysis methods are considerably less developed and mature for HTR analysis than those currently used for Light Water Reactors (LWRs). Compared to LWRs, the HTR transient analysis is more demanding since it requires proper treatment of both slower and much longer transients (of time scale in hours and days) and fast and short transients (of time scale in minutes and seconds). There is limited operation and experimental data available for HTRs for validation of coupled multi-physics methodologies. This PhD work developed and verified reliable high fidelity coupled multi-physics models subsequently implemented in robust, efficient, and accurate computational tools to analyse the neutronics and thermal-hydraulic behaviour for design optimization and safety evaluation of PBMR concept The study provided a contribution to a greater accuracy of neutronics calculations by including the feedback from thermal hydraulics driven temperature calculation and various multi-physics effects that can influence it. Consideration of the feedback due to the influence of leakage was taken into account by development and implementation of improved buckling feedback models. Modifications were made in the calculation procedure to ensure that the xenon depletion models were accurate for proper interpolation from cross section tables. To achieve this, the NEM/THERMIX coupled code system was developed to create the system that is efficient and stable over the duration of transient calculations that last over several tens of hours. Another achievement of the PhD thesis was development and demonstration of full-physics, three-dimensional safety analysis

  3. Musculoskeletal modelling of the lumbar spine to explore functional interactions between back muscle loads and intervertebral disc multiphysics

    Directory of Open Access Journals (Sweden)

    Themis eToumanidou

    2015-08-01

    Full Text Available During daily activities, complex biomechanical interactions influence the biophysical regulation of intervertebral discs (IVDs, and transfers of mechanical loads are largely controlled by the stabilizing action of spine muscles. Muscle and other internal forces cannot be easily measured directly in the lumbar spine. Hence, biomechanical models are important tools for the evaluation of the loads in those tissues involved in low back disorders. Muscle force estimations in most musculoskeletal models mainly rely, however, on inverse calculations and static optimizations that limit the predictive power of the numerical calculations. In order to contribute to the development of predictive systems, we coupled a predictive muscle model with the passive resistance of the spine tissues, in a L3-S1 musculoskeletal finite element model with osmo-poromechanical IVD descriptions. The model included 46 fascicles of the major back muscles that act on the lower spine. The muscle model interacted with activity-related loads imposed to the osteoligamentous structure, as standing position and night rest were simulated through distributed upper body mass and free IVD swelling, respectively. Calculations led to intradiscal pressure values within ranges of values measured in vivo. Disc swelling led to muscle activation and muscle force distributions that seemed particularly appropriate to counterbalance the anterior body mass effect in standing. Our simulations pointed out a likely existence of a functional balance between stretch-induced muscle activation and IVD multiphysics towards improved mechanical stability of the lumbar spine under standing. This balance suggests that proper night rest contributes to mechanically strengthen the spine during day activity.

  4. Multiphysics modeling of selective laser sintering/melting

    Science.gov (United States)

    Ganeriwala, Rishi Kumar

    A significant percentage of total global employment is due to the manufacturing industry. However, manufacturing also accounts for nearly 20% of total energy usage in the United States according to the EIA. In fact, manufacturing accounted for 90% of industrial energy consumption and 84% of industry carbon dioxide emissions in 2002. Clearly, advances in manufacturing technology and efficiency are necessary to curb emissions and help society as a whole. Additive manufacturing (AM) refers to a relatively recent group of manufacturing technologies whereby one can 3D print parts, which has the potential to significantly reduce waste, reconfigure the supply chain, and generally disrupt the whole manufacturing industry. Selective laser sintering/melting (SLS/SLM) is one type of AM technology with the distinct advantage of being able to 3D print metals and rapidly produce net shape parts with complicated geometries. In SLS/SLM parts are built up layer-by-layer out of powder particles, which are selectively sintered/melted via a laser. However, in order to produce defect-free parts of sufficient strength, the process parameters (laser power, scan speed, layer thickness, powder size, etc.) must be carefully optimized. Obviously, these process parameters will vary depending on material, part geometry, and desired final part characteristics. Running experiments to optimize these parameters is costly, energy intensive, and extremely material specific. Thus a computational model of this process would be highly valuable. In this work a three dimensional, reduced order, coupled discrete element - finite difference model is presented for simulating the deposition and subsequent laser heating of a layer of powder particles sitting on top of a substrate. Validation is provided and parameter studies are conducted showing the ability of this model to help determine appropriate process parameters and an optimal powder size distribution for a given material. Next, thermal stresses upon

  5. Multi-Physics and Multi-Scale Deterioration Modelling of Reinforced Concrete

    DEFF Research Database (Denmark)

    Michel, Alexander; Stang, Henrik; Lepech, M.;

    2016-01-01

    , methods and tools for modelling decades-long deterioration and maintenance are much less developed. In this paper, a multi-physics and multi-scale modelling approach for structural deterioration of reinforced concrete components due to reinforcement corrosion is presented. The multi-disciplinary modelling......Deterioration of reinforced concrete infrastructure such as bridges, tunnels, and buildings represents one of the major challenges currently facing developed countries. While engineering tools and methods for structural modelling and design of new reinforced concrete infrastructure are mature...

  6. Multi-physics approach to the analysis of molten salt reactors

    Energy Technology Data Exchange (ETDEWEB)

    Nicolino, Claudio; Dulla, Sandra; Ravetto, Piero [Politecnico di Torino, DENER, Corso Duca degli Abruzzi, 24 - 10129 Torino (Italy); Lapenta, Giovanni [Departement Wiskunde, Katholieke Universiteit Leuven, Celestijnenlaan 200B, Heverlee, B-3001 (Belgium)

    2008-07-01

    A fully-coupled multi-physics non-linear model for the dynamic description of liquid-fuel multiplying fast systems is presented. Different physical variables are considered in the model, such as neutron flux, precursor concentration, velocity field and temperature. The corresponding set of equations is implemented in a code solved by a Jacobian-Free Newton-Krylov algorithm. The results presented enlighten the presence of unusual connections among the different aspects of the problem treated. A particular accent is posed on the description of those special features that need to be taken into account when dealing with a realistic analysis of a molten salt fast reactor. (authors)

  7. A Reduced Basis Framework: Application to large scale non-linear multi-physics problems

    Directory of Open Access Journals (Sweden)

    Daversin C.

    2013-12-01

    Full Text Available In this paper we present applications of the reduced basis method (RBM to large-scale non-linear multi-physics problems. We first describe the mathematical framework in place and in particular the Empirical Interpolation Method (EIM to recover an affine decomposition and then we propose an implementation using the open-source library Feel++ which provides both the reduced basis and finite element layers. Large scale numerical examples are shown and are connected to real industrial applications arising from the High Field Resistive Magnets development at the Laboratoire National des Champs Magnétiques Intenses.

  8. Study of stability of dc glow discharges with the use of Comsol Multiphysics software

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, P G C; Benilov, M S; Faria, M J [Departamento de Fisica, Universidade da Madeira, Largo do Municipio, 9000 Funchal (Portugal)

    2011-10-19

    Stability of different axially symmetric modes of current transfer in dc glow discharges is investigated in the framework of the linear stability theory with the use of Comsol Multiphysics software. Conditions of current-controlled microdischarges in xenon are treated as an example. Both real and complex eigenvalues have been detected, meaning that perturbations can vary with time both monotonically and with oscillations. In general, results given by the linear stability theory confirm intuitive concepts developed in the literature and conform to the experiment. On the other hand, suggestions are provided for further experimental and theoretical work.

  9. Multiphysics simulation of thermal phenomena in direct laser metal powder deposition

    CSIR Research Space (South Africa)

    Pityana, SL

    2016-11-01

    Full Text Available The direct laser metal deposition (DLMD) is a recently developed technique for manufacturing solid parts, layer by layer, directly from powder. The process uses a high power laser beam focused onto a metallic substrate to generate a molten pool...

  10. High-order Spatio-temporal Schemes for Coupled, Multi-physics Reactor Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Mr. Vijay S. Mahadevan; Dr. Jean C. Ragusa

    2008-09-01

    This report summarizes the work done in the summer of 08 by the Ph.D. student Vijay Mahadevan. The main focus of the work was to coupled 3-D neutron difusion to 3-D heat conduction in parallel with accuracy greater than or equal to 2nd order in space and time. Results show that the goal was attained.

  11. RELAP-7 Level 2 Milestone Report: Demonstration of a Steady State Single Phase PWR Simulation with RELAP-7

    Energy Technology Data Exchange (ETDEWEB)

    David Andrs; Ray Berry; Derek Gaston; Richard Martineau; John Peterson; Hongbin Zhang; Haihua Zhao; Ling Zou

    2012-05-01

    evolve with time. RELAP-7 is a MOOSE-based application. MOOSE (Multiphysics Object-Oriented Simulation Environment) is a framework for solving computational engineering problems in a well-planned, managed, and coordinated way. By leveraging millions of lines of open source software packages, such as PETSC (a nonlinear solver developed at Argonne National Laboratory) and LibMesh (a Finite Element Analysis package developed at University of Texas), MOOSE significantly reduces the expense and time required to develop new applications. Numerical integration methods and mesh management for parallel computation are provided by MOOSE. Therefore RELAP-7 code developers only need to focus on physics and user experiences. By using the MOOSE development environment, RELAP-7 code is developed by following the same modern software design paradigms used for other MOOSE development efforts. There are currently over 20 different MOOSE based applications ranging from 3-D transient neutron transport, detailed 3-D transient fuel performance analysis, to long-term material aging. Multi-physics and multiple dimensional analyses capabilities can be obtained by coupling RELAP-7 and other MOOSE based applications and by leveraging with capabilities developed by other DOE programs. This allows restricting the focus of RELAP-7 to systems analysis-type simulations and gives priority to retain and significantly extend RELAP5's capabilities.

  12. Advanced Multiphysics Thermal-Hydraulics Models for the High Flux Isotope Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Prashant K [ORNL; Freels, James D [ORNL

    2015-01-01

    Engineering design studies to determine the feasibility of converting the High Flux Isotope Reactor (HFIR) from using highly enriched uranium (HEU) to low-enriched uranium (LEU) fuel are ongoing at Oak Ridge National Laboratory (ORNL). This work is part of an effort sponsored by the US Department of Energy (DOE) Reactor Conversion Program. HFIR is a very high flux pressurized light-water-cooled and moderated flux-trap type research reactor. HFIR s current missions are to support neutron scattering experiments, isotope production, and materials irradiation, including neutron activation analysis. Advanced three-dimensional multiphysics models of HFIR fuel were developed in COMSOL software for safety basis (worst case) operating conditions. Several types of physics including multilayer heat conduction, conjugate heat transfer, turbulent flows (RANS model) and structural mechanics were combined and solved for HFIR s inner and outer fuel elements. Alternate design features of the new LEU fuel were evaluated using these multiphysics models. This work led to a new, preliminary reference LEU design that combines a permanent absorber in the lower unfueled region of all of the fuel plates, a burnable absorber in the inner element side plates, and a relocated and reshaped (but still radially contoured) fuel zone. Preliminary results of estimated thermal safety margins are presented. Fuel design studies and model enhancement continue.

  13. Multiphysics modelling, quantum chemistry and risk analysis for corrosion inhibitor design and lifetime prediction.

    Science.gov (United States)

    Taylor, C D; Chandra, A; Vera, J; Sridhar, N

    2015-01-01

    Organic corrosion inhibitors can provide an effective means to extend the life of equipment in aggressive environments, decrease the environmental, economic, health and safety risks associated with corrosion failures and enable the use of low cost steels in place of corrosion resistant alloys. To guide the construction of advanced models for the design and optimization of the chemical composition of organic inhibitors, and to develop predictive tools for inhibitor performance as a function of alloy and environment, a multiphysics model has been constructed following Staehle's principles of "domains and microprocesses". The multiphysics framework provides a way for science-based modelling of the various phenomena that impact inhibitor efficiency, including chemical thermodynamics and speciation, oil/water partitioning, effect of the inhibitor on multiphase flow, surface adsorption and self-assembled monolayer formation, and the effect of the inhibitor on cathodic and anodic reaction pathways. The fundamental tools required to solve the resulting modelling from a first-principles perspective are also described. Quantification of uncertainty is significant to the development of lifetime prediction models, due to their application for risk management. We therefore also discuss how uncertainty analysis can be coupled with the first-principles approach laid out in this paper.

  14. A novel phenomenological multi-physics model of Li-ion battery cells

    Science.gov (United States)

    Oh, Ki-Yong; Samad, Nassim A.; Kim, Youngki; Siegel, Jason B.; Stefanopoulou, Anna G.; Epureanu, Bogdan I.

    2016-09-01

    A novel phenomenological multi-physics model of Lithium-ion battery cells is developed for control and state estimation purposes. The model can capture electrical, thermal, and mechanical behaviors of battery cells under constrained conditions, e.g., battery pack conditions. Specifically, the proposed model predicts the core and surface temperatures and reaction force induced from the volume change of battery cells because of electrochemically- and thermally-induced swelling. Moreover, the model incorporates the influences of changes in preload and ambient temperature on the force considering severe environmental conditions electrified vehicles face. Intensive experimental validation demonstrates that the proposed multi-physics model accurately predicts the surface temperature and reaction force for a wide operational range of preload and ambient temperature. This high fidelity model can be useful for more accurate and robust state of charge estimation considering the complex dynamic behaviors of the battery cell. Furthermore, the inherent simplicity of the mechanical measurements offers distinct advantages to improve the existing power and thermal management strategies for battery management.

  15. ALE-AMR: A new 3D multi-physics code for modeling laser/target effects

    Science.gov (United States)

    Koniges, A. E.; Masters, N. D.; Fisher, A. C.; Anderson, R. W.; Eder, D. C.; Kaiser, T. B.; Bailey, D. S.; Gunney, B.; Wang, P.; Brown, B.; Fisher, K.; Hansen, F.; Maddox, B. R.; Benson, D. J.; Meyers, M.; Geille, A.

    2010-08-01

    We have developed a new 3D multi-physics multi-material code, ALE-AMR, for modeling laser/target effects including debris/shrapnel generation. The code combines Arbitrary Lagrangian Eulerian (ALE) hydrodynamics with Adaptive Mesh Refinement (AMR) to connect the continuum to microstructural regimes. The code is unique in its ability to model hot radiating plasmas and cold fragmenting solids. New numerical techniques were developed for many of the physics packages to work efficiency on a dynamically moving and adapting mesh. A flexible strength/failure framework allows for pluggable material models. Material history arrays are used to store persistent data required by the material models, for instance, the level of accumulated damage or the evolving yield stress in J2 plasticity models. We model ductile metals as well as brittle materials such as Si, Be, and B4C. We use interface reconstruction based on volume fractions of the material components within mixed zones and reconstruct interfaces as needed. This interface reconstruction model is also used for void coalescence and fragmentation. The AMR framework allows for hierarchical material modeling (HMM) with different material models at different levels of refinement. Laser rays are propagated through a virtual composite mesh consisting of the finest resolution representation of the modeled space. A new 2nd order accurate diffusion solver has been implemented for the thermal conduction and radiation transport packages. The code is validated using laser and x-ray driven spall experiments in the US and France. We present an overview of the code and simulation results.

  16. Simulating the Thermal Response of High Explosives on Time Scales of Days to Microseconds

    Energy Technology Data Exchange (ETDEWEB)

    Yoh, J J; McClelland, M A

    2003-07-16

    We present an overview of computational techniques for simulating the thermal cookoff of high explosives using a multi-physics hydrodynamics code, ALE3D. Recent improvements to the code have aided our computational capability in modeling the response of energetic materials systems exposed to extreme thermal environments, such as fires. We consider an idealized model process for a confined explosive involving the transition from slow heating to rapid deflagration in which the time scale changes from days to hundreds of microseconds. The heating stage involves thermal expansion and decomposition according to an Arrhenius kinetics model while a pressure-dependent burn model is employed during the explosive phase. We describe and demonstrate the numerical strategies employed to make the transition from slow to fast dynamics.

  17. Computational physics and applied mathematics capability review June 8-10, 2010 (Advance materials to committee members)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Stephen R [Los Alamos National Laboratory

    2010-01-01

    Los Alamos National Laboratory will review its Computational Physics and Applied Mathematics (CPAM) capabilities in 2010. The goals of capability reviews are to assess the quality of science, technology, and engineering (STE) performed by the capability, evaluate the integration of this capability across the Laboratory and within the scientific community, examine the relevance of this capability to the Laboratory's programs, and provide advice on the current and future directions of this capability. This is the first such review for CPAM, which has a long and unique history at the laboratory, starting from the inception of the Laboratory in 1943. The CPAM capability covers an extremely broad technical area at Los Alamos, encompassing a wide array of disciplines, research topics, and organizations. A vast array of technical disciplines and activities are included in this capability, from general numerical modeling, to coupled mUlti-physics simulations, to detailed domain science activities in mathematics, methods, and algorithms. The CPAM capability involves over 12 different technical divisions and a majority of our programmatic and scientific activities. To make this large scope tractable, the CPAM capability is broken into the following six technical 'themes.' These themes represent technical slices through the CP AM capability and collect critical core competencies of the Laboratory, each of which contributes to the capability (and each of which is divided into multiple additional elements in the detailed descriptions of the themes in subsequent sections): (1) Computational Fluid Dynamics - This theme speaks to the vast array of scientific capabilities for the simulation of fluids under shocks, low-speed flow, and turbulent conditions - which are key, historical, and fundamental strengths of the laboratory; (2) Partial Differential Equations - The technical scope of this theme is the applied mathematics and numerical solution of partial

  18. Improving wheat simulation capabilities in Australia from a cropping systems perspective: Water and nitrogen effects on spring wheat in a semi-arid environment.

    NARCIS (Netherlands)

    Meinke, H.; Hammer, G.L.; Keulen, van H.; Rabbinge, R.; Keating, B.A.

    1997-01-01

    Systems approaches can help to evaluate and improve the agronomic and economic viability of nitrogen application in the frequently water-limited environments. This requires a sound understanding of crop physiological processes and well tested simulation models. Thus, this experiment on spring wheat

  19. 我国汽车企业创新能力动态模拟的研究%A Study on the Dynamic Simulation on the Innovation Capability of Chinese Automotive Enterprises

    Institute of Scientific and Technical Information of China (English)

    张峥; 刘晓静; 何园

    2012-01-01

    将系统动力学和战略地图方法相结合,从财务、客户、内部运营流程和学习与发展4个层面分析影响创新能力的因素,构建创新能力模型,并对重要影响因素进行模拟.结果表明,我国汽车企业应进一步完善创新能力体系;汽车产业政策的制定应以提高创新能力作为企业发展的导向;自主品牌销售份额与生产企业的创新能力具有相互促进作用;政府扶持力度对提升汽车企业创新能力具有重要作用,但宜控制在合理范围内.%By combining system dynamics and strategic map method and analyzing the factors affecting innovation capability from the four aspects of finance, customers, internal operational process and learning & development , the innovation capability model is constructed and its important influencing factors are simulated. The results indicate that Chinese automotive industry should further perfect innovation capability system; in formulating industrial policies of Chinese automotive industry, the enhancement of innovation capability should be taken as a guide for the development of enterprises; the sales share of vehicles with autonomous brand and the innovation capability of manufacturers can effectively promote each other; and government's support efforts within a reasonable degree will play an important role in raising innovation capability of automotive enterprises.

  20. Off-gas Adsorption Model and Simulation - OSPREY

    Energy Technology Data Exchange (ETDEWEB)

    Veronica J Rutledge

    2013-10-01

    The absence of industrial scale nuclear fuel reprocessing in the U.S. has precluded the necessary driver for developing the advanced simulation capability now prevalent in so many other countries. Thus, it is essential to model complex series of unit operations to simulate, understand, and predict inherent transient behavior. A capability of accurately simulating the dynamic behavior of advanced fuel cycle separation processes is expected to provide substantial cost savings and many technical benefits. To support this capability, a modeling effort focused on the off-gas treatment system of a used nuclear fuel recycling facility is in progress. The off-gas separation consists of a series of scrubbers and adsorption beds to capture constituents of interest. Dynamic models are being developed to simulate each unit operation involved so each unit operation can be used as a stand-alone model and in series with multiple others. Currently, an adsorption model has been developed within Multi-physics Object Oriented Simulation Environment (MOOSE) developed at the Idaho National Laboratory (INL). Off-gas Separation and REcoverY (OSPREY) models the adsorption of offgas constituents for dispersed plug flow in a packed bed under non-isothermal and non-isobaric conditions. Inputs to the model include gas composition, sorbent and column properties, equilibrium and kinetic data, and inlet conditions. The simulation outputs component concentrations along the column length as a function of time from which breakthrough data can be obtained. The breakthrough data can be used to determine bed capacity, which in turn can be used to size columns. In addition to concentration data, the model predicts temperature along the column length as a function of time and pressure drop along the column length. A description of the OSPREY model, results from krypton adsorption modeling and plans for modeling the behavior of iodine, xenon, and tritium will be discussed.

  1. Mobile Test Capabilities

    Data.gov (United States)

    Federal Laboratory Consortium — The Electrical Power Mobile Test capabilities are utilized to conduct electrical power quality testing on aircraft and helicopters. This capability allows that the...

  2. IAC - INTEGRATED ANALYSIS CAPABILITY

    Science.gov (United States)

    Frisch, H. P.

    1994-01-01

    Integration via Mesh Interpolation Coefficients), which transforms field values from one model to another; LINK, which simplifies incorporation of user specific modules into IAC modules; and DATAPAC, the National Bureau of Standards statistical analysis package. The IAC database contains structured files which provide a common basis for communication between modules and the executive system, and can contain unstructured files such as NASTRAN checkpoint files, DISCOS plot files, object code, etc. The user can define groups of data and relations between them. A full data manipulation and query system operates with the database. The current interface modules comprise five groups: 1) Structural analysis - IAC contains a NASTRAN interface for standalone analysis or certain structural/control/thermal combinations. IAC provides enhanced structural capabilities for normal modes and static deformation analysis via special DMAP sequences. IAC 2.5 contains several specialized interfaces from NASTRAN in support of multidisciplinary analysis. 2) Thermal analysis - IAC supports finite element and finite difference techniques for steady state or transient analysis. There are interfaces for the NASTRAN thermal analyzer, SINDA/SINFLO, and TRASYS II. FEMNET, which converts finite element structural analysis models to finite difference thermal analysis models, is also interfaced with the IAC database. 3) System dynamics - The DISCOS simulation program which allows for either nonlinear time domain analysis or linear frequency domain analysis, is fully interfaced to the IAC database management capability. 4) Control analysis - Interfaces for the ORACLS, SAMSAN, NBOD2, and INCA programs allow a wide range of control system analyses and synthesis techniques. Level 2.5 includes EIGEN, which provides tools for large order system eigenanalysis, and BOPACE, which allows for geometric capabilities and finite element analysis with nonlinear material. Also included in IAC level 2.5 is SAMSAN 3.1, an

  3. An Alternative Optimization Model and Robust Experimental Design for the Assignment Scheduling Capability for Unmanned Aerial Vehicles (ASC-U) Simulation

    Science.gov (United States)

    2007-06-01

    1 Paul L. Francis, “The Army’s Future Combat Systems’ Features, Risks and Alternatives,” Congressional Testimony...Systems’ Features, Risks and Alternatives,” Congressional Testimony, United States General Accounting Office, GAO-04-635T, 1 April 2004, p. 4. 3 Ibid...arbitrary “hit-or-miss” techniques that simply use a large number of unsystematic runs.59 Although simulation experiments can be viewed as a subset of

  4. Adding Complex Terrain and Stable Atmospheric Condition Capability to the OpenFOAM-based Flow Solver of the Simulator for On/Offshore Wind Farm Applications (SOWFA): Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Churchfield, M. J.; Sang, L.; Moriarty, P. J.

    2013-09-01

    This paper describes changes made to NREL's OpenFOAM-based wind plant aerodynamics solver such that it can compute the stably stratified atmospheric boundary layer and flow over terrain. Background about the flow solver, the Simulator for Off/Onshore Wind Farm Applications (SOWFA) is given, followed by details of the stable stratification/complex terrain modifications to SOWFA, along with somepreliminary results calculations of a stable atmospheric boundary layer and flow over a simply set of hills.

  5. Adding complex terrain and stable atmospheric condition capability to the OpenFOAM-based flow solver of the simulator for on/offshore wind farm applications (SOWFA

    Directory of Open Access Journals (Sweden)

    Churchfield Matthew J.

    2014-01-01

    Full Text Available The National Renewable Energy Laboratory's Simulator for On/Offshore Wind Farm Applications contains an OpenFOAM-based flow solver for performing large-eddy simulation of flow through wind plants. The solver computes the atmospheric boundary layer flow and models turbines with actuator lines. Until recently, the solver was limited to flows over flat terrain and could only use the standard Smagorinsky subgrid-scale model. In this work, we present our improvements to the flow solver that enable us to 1 use any OpenFOAM-standard subgrid-scale model and 2 simulate flow over complex terrain. We used the flow solver to compute a stably stratified atmospheric boundary layer using both the standard and the Lagrangian-averaged scale-independent dynamic Smagorinsky models. Surprisingly, the results using the standard Smagorinsky model compare well to other researchers' results of the same case, although it is often said that the standard Smagorinsky model is too dissipative for accurate stable stratification calculations. The scale-independent dynamic subgrid-scale model produced poor results, probably due to the spikes in model constant with values as high as 4.6. We applied a simple bounding of the model constant to remove these spikes, which caused the model to produce results much more in line with other researchers' results. We also computed flow over a simple hilly terrain and performed some basic qualitative analysis to verify the proper operation of the terrain-local surface stress model we employed.

  6. Sensitivity and Uncertainty Analysis of Coupled Reactor Physics Problems: Method Development for Multi-Physics in Reactors

    NARCIS (Netherlands)

    Perkó, Z.

    2015-01-01

    This thesis presents novel adjoint and spectral methods for the sensitivity and uncertainty (S&U) analysis of multi-physics problems encountered in the field of reactor physics. The first part focuses on the steady state of reactors and extends the adjoint sensitivity analysis methods well establish

  7. Sensitivity and Uncertainty Analysis of Coupled Reactor Physics Problems: Method Development for Multi-Physics in Reactors

    NARCIS (Netherlands)

    Perkó, Z.

    2015-01-01

    This thesis presents novel adjoint and spectral methods for the sensitivity and uncertainty (S&U) analysis of multi-physics problems encountered in the field of reactor physics. The first part focuses on the steady state of reactors and extends the adjoint sensitivity analysis methods well

  8. University Research in Support of TREAT Modeling and Simulation, FY 2016

    Energy Technology Data Exchange (ETDEWEB)

    DeHart, Mark David [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    Idaho National Laboratory is currently evolving the modeling and simulation (M&S) capability that will enable improved core operation as well as design and analysis of TREAT experiments. This M&S capability primarily uses MAMMOTH, a reactor physics application being developed under the Multi-physics Object Oriented Simulation Environment (MOOSE) framework. MAMMOTH allows the coupling of a number of other MOOSE-based applications. In support of this research, INL is working with four universities to explore advanced solution methods that will complement or augment capabilities in MAMMOTH. This report consists of a collection of year end summaries of research from the universities performed in support of TREAT modeling and simulation. This research was led by Prof. Sedat Goluoglu at the University of Florida, Profs. Jim Morel and Jean Ragusa at Texas A&M University, Profs. Benoit Forget and Kord Smith at Massachusetts Institute of Technology, Prof. Leslie Kerby of Idaho State University and Prof. Barry Ganapol of University of Arizona. A significant number of students were supported at various levels though the projects and, for some, also as interns at INL.

  9. Characterization of a 6 kW high-flux solar simulator with an array of xenon arc lamps capable of concentrations of nearly 5000 suns

    Energy Technology Data Exchange (ETDEWEB)

    Gill, Robert; Bush, Evan; Loutzenhiser, Peter, E-mail: peter.loutzenhiser@me.gatech.edu [George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0405 (United States); Haueter, Philipp [Haueter Engineering Gmbh, Rombach 5022 (Switzerland)

    2015-12-15

    A systematic methodology for characterizing a novel and newly fabricated high-flux solar simulator is presented. The high-flux solar simulator consists of seven xenon short-arc lamps mounted in truncated ellipsoidal reflectors. Characterization of spatial radiative heat flux distribution was performed using calorimetric measurements of heat flow coupled with CCD camera imaging of a Lambertian target mounted in the focal plane. The calorimetric measurements and images of the Lambertian target were obtained in two separate runs under identical conditions. Detailed modeling in the high-flux solar simulator was accomplished using Monte Carlo ray tracing to capture radiative heat transport. A least-squares regression model was used on the Monte Carlo radiative heat transfer analysis with the experimental data to account for manufacturing defects. The Monte Carlo ray tracing was calibrated by regressing modeled radiative heat flux as a function of specular error and electric power to radiation conversion onto measured radiative heat flux from experimental results. Specular error and electric power to radiation conversion efficiency were 5.92 ± 0.05 mrad and 0.537 ± 0.004, respectively. An average radiative heat flux with 95% errors bounds of 4880 ± 223 kW ⋅ m{sup −2} was measured over a 40 mm diameter with a cavity-type calorimeter with an apparent absorptivity of 0.994. The Monte Carlo ray-tracing resulted in an average radiative heat flux of 893.3 kW ⋅ m{sup −2} for a single lamp, comparable to the measured radiative heat fluxes with 95% error bounds of 892.5 ± 105.3 kW ⋅ m{sup −2} from calorimetry.

  10. Multi-physics optimization of three-dimensional microvascular polymeric components

    Science.gov (United States)

    Aragón, Alejandro M.; Saksena, Rajat; Kozola, Brian D.; Geubelle, Philippe H.; Christensen, Kenneth T.; White, Scott R.

    2013-01-01

    This work discusses the computational design of microvascular polymeric materials, which aim at mimicking the behavior found in some living organisms that contain a vascular system. The optimization of the topology of the embedded three-dimensional microvascular network is carried out by coupling a multi-objective constrained genetic algorithm with a finite-element based physics solver, the latter validated through experiments. The optimization is carried out on multiple conflicting objective functions, namely the void volume fraction left by the network, the energy required to drive the fluid through the network and the maximum temperature when the material is subjected to thermal loads. The methodology presented in this work results in a viable alternative for the multi-physics optimization of these materials for active-cooling applications.

  11. Numerical methods for reliability and safety assessment multiscale and multiphysics systems

    CERN Document Server

    Hami, Abdelkhalak

    2015-01-01

    This book offers unique insight on structural safety and reliability by combining computational methods that address multiphysics problems, involving multiple equations describing different physical phenomena, and multiscale problems, involving discrete sub-problems that together  describe important aspects of a system at multiple scales. The book examines a range of engineering domains and problems using dynamic analysis, nonlinear methods, error estimation, finite element analysis, and other computational techniques. This book also: ·       Introduces novel numerical methods ·       Illustrates new practical applications ·       Examines recent engineering applications ·       Presents up-to-date theoretical results ·       Offers perspective relevant to a wide audience, including teaching faculty/graduate students, researchers, and practicing engineers

  12. Design and Optimization of Gearless Drives using Multi-Physics Approach

    DEFF Research Database (Denmark)

    Andersen, Søren Bøgh

    . The optimization resulted in a mass reduction of 4.0% and a decrease of losses of 9.9% compared to the original drive design. The thesis also opens new research fronts and highlights three new necessary research aspects for further development of the design processes of large gearless drives based on a multi......Many different technical areas are involved in the design process of large gearless drives for the mining industry, aiming at correctly describing the electrical-mechanical-thermal behavior of the drive. So far, these various technical areas are being treated more or less separately......, and no descriptions or references are found concerning the modeling of these large drives using coupled multi-physics models, which allow an overall optimization of this kind of machinery. In this framework, the goal of this thesis is to create reliable and coherent interdisciplinary mathematical models based...

  13. On the multi-physics of mass-transfer across fluid interfaces

    CERN Document Server

    Bothe, Dieter

    2015-01-01

    Mass transfer of gaseous components from rising bubbles to the ambient liquid can be described based on continuum mechanical sharp-interface balances of mass, momentum and species mass. In this context, the standard model consists of the two-phase Navier-Stokes equations for incompressible fluids with constant surface tension, complemented by reaction-advection-diffusion equations for all constituents, employing Fick's law. This standard model is inconsistent with the continuity equation, the momentum balance and the second law of thermodynamics. The present paper reports on the details of these severe shortcomings and provides thermodynamically consistent model extensions which are required to capture various phenomena which occur due to the multi-physics of interfacial mass transfer. In particular, we provide a simple derivation of the interface Maxwell-Stefan equations which does not require a time scale separation, while the main contribution is to show how interface concentrations and interface chemical ...

  14. Multiphysics Modeling of an Annular Linear Induction Pump With Applications to Space Nuclear Power Systems

    Science.gov (United States)

    Kilbane, J.; Polzin, K. A.

    2014-01-01

    An annular linear induction pump (ALIP) that could be used for circulating liquid-metal coolant in a fission surface power reactor system is modeled in the present work using the computational COMSOL Multiphysics package. The pump is modeled using a two-dimensional, axisymmetric geometry and solved under conditions similar to those used during experimental pump testing. Real, nonlinear, temperature-dependent material properties can be incorporated into the model for both the electrically-conducting working fluid in the pump (NaK-78) and structural components of the pump. The intricate three-phase coil configuration of the pump is implemented in the model to produce an axially-traveling magnetic wave that is qualitatively similar to the measured magnetic wave. The model qualitatively captures the expected feature of a peak in efficiency as a function of flow rate.

  15. Multi-physics analysis of permanent magnet tubular linear motors under severe volumetric and thermal constraints

    Institute of Scientific and Technical Information of China (English)

    李方; 叶佩青; 张辉

    2016-01-01

    Permanent magnet tubular linear motors (TLMs) arranged in multiple rows and multiple columns used for a radiotherapy machine were studied. Due to severe volumetric and thermal constraints, the TLMs were at high risk of overheating. To predict the performance of the TLMs accurately, a multi-physics analysis approach was proposed. Specifically, it considered the coupling effects amongst the electromagnetic and the thermal models of the TLMs, as well as the fluid model of the surrounding air. To reduce computation cost, both the electromagnetic and the thermal models were based on lumped-parameter methods. Only a minimum set of numerical computation (computational fluid dynamics, CFD) was performed to model the complex fluid behavior. With the proposed approach, both steady state and transient state temperature distributions, thermal rating and permissible load can be predicted. The validity of this approach is verified through the experiment.

  16. Multi-physics coupling field finite element analysis on giant magnetostrictive materials smart component

    Institute of Scientific and Technical Information of China (English)

    Zhang-rong ZHAO; Yi-jie WU; Xin-jian GU; Lei ZHANG; Ji-feng YANG

    2009-01-01

    This study presents a new method to solve the difficult problem of precise machining a non-cylinder pinhole of a piston using embedded giant magnetostrictive material(GMM)in the component.We propose the finite element model of GMM smart component in electric,magnetic,and mechanical fields by step computation to optimize the design of GMM smart component.The proposed model is implemented by using COMSOL multi-physics V3.2a.The effects of the smart component on the deformation and the system resonance frequencies are studied.The results calculated by the model are in excellent agreement (relative errors are below 10%)with the experimental values.

  17. TerraFERMA: The Transparent Finite Element Rapid Model Assembler for multiphysics problems in Earth sciences

    Science.gov (United States)

    Wilson, Cian R.; Spiegelman, Marc; van Keken, Peter E.

    2017-02-01

    We introduce and describe a new software infrastructure TerraFERMA, the Transparent Finite Element Rapid Model Assembler, for the rapid and reproducible description and solution of coupled multiphysics problems. The design of TerraFERMA is driven by two computational needs in Earth sciences. The first is the need for increased flexibility in both problem description and solution strategies for coupled problems where small changes in model assumptions can lead to dramatic changes in physical behavior. The second is the need for software and models that are more transparent so that results can be verified, reproduced, and modified in a manner such that the best ideas in computation and Earth science can be more easily shared and reused. TerraFERMA leverages three advanced open-source libraries for scientific computation that provide high-level problem description (FEniCS), composable solvers for coupled multiphysics problems (PETSc), and an options handling system (SPuD) that allows the hierarchical management of all model options. TerraFERMA integrates these libraries into an interface that organizes the scientific and computational choices required in a model into a single options file from which a custom compiled application is generated and run. Because all models share the same infrastructure, models become more reusable and reproducible, while still permitting the individual researcher considerable latitude in model construction. TerraFERMA solves partial differential equations using the finite element method. It is particularly well suited for nonlinear problems with complex coupling between components. TerraFERMA is open-source and available at http://terraferma.github.io, which includes links to documentation and example input files.

  18. Selection of High Performance Alloy for Gas Turbine Blade Using Multiphysics Analysis

    Directory of Open Access Journals (Sweden)

    H Khawaja

    2016-09-01

    Full Text Available With the extensive increase in the utilization of energy resources in the modern era, the need of energy extraction from various resources has pronounced in recent years. Thus comprehensive efforts have been made around the globe in the technological development of turbo machines where means of energy extraction is energized fluids. This development led the aviation industry to power boost due to better performing engines. Meanwhile, the structural conformability requirements relative to the functional requirements have also increased with the advent of newer, better performing materials. Thus there is a need to study the material behavior and its usage with the idea of selecting the best possible material for its application. In this work a gas turbine blade of a small turbofan engine, where geometry and aerodynamic data was available, was analyzed for its structural behavior in the proposed mission envelope, where the engine turbine is subjected to high thermal, inertial and aerodynamic loads. Multiphysics Finite Element (FE linear stress analysis was carried out on the turbine blade. The results revealed the upper limit of Ultimate Tensile Strength (UTS for the blade. Based on the limiting factor, high performance alloys were selected from the literature. The two most recommended alloy categories for gas turbine blades are NIMONIC and INCONEL from where total of 21 types of INCONEL alloys and 12 of NIMONIC alloys, available on commercial bases, were analyzed individually to meet the structural requirements. After applying selection criteria, four alloys were finalized from NIMONIC and INCONEL alloys for further analysis. On the basis of stress-strain behavior of finalized alloys, the Multiphysics FE nonlinear stress analysis was then carried out for the selection of the individual alloy by imposing a restriction of Ultimate Factor of Safety (UFOS of 1.33 and yield strength. Final selection is made keeping in view other factors

  19. The cell method for electrical engineering and multiphysics problems. An introduction

    Energy Technology Data Exchange (ETDEWEB)

    Alotto, Piergiorgio [Padova Univ. (Italy). Dipt. di Ingegneria Industriale; Freschi, Fabio; Repetto, Maurizio [Politecnico di Torino (Italy). Dipt. Energia; Rosso, Carlo [Politecnico di Torino (Italy). Dipt. di Ingegneria Meccanica e Aerospaziale

    2013-03-01

    Introduction to the Cell Method, a numerical method for the solution of a large class of physical problems as an alternative to the classical Finite Element techniques. Presents important implementation aspects of the technique as well as a complete fully working computer code for the solution of three-dimensional stationary thermal problem. All chapters include extensive bibliographic references. This book presents a numerical scheme for the solution of field problems governed by partial differential equations: the cell method. The technique lends itself naturally to the solution of multiphysics problems with several interacting phenomena. The Cell Method, based on a space-time tessellation, is intimately related to the work of Tonti and to his ideas of classification diagrams or, as they are nowadays called, Tonti diagrams: a graphical representation of the problem's equations made possible by a suitable selection of a space-time framework relating physical variables to each other. The main features of the cell method are presented and links with many other discrete numerical methods (finite integration techniques, finite difference time domain, finite volumes, mimetic finite differences, etc.) are discussed. After outlining the theoretical basis of the method, a set of physical problems which have been solved with the cell method is described. These single and multiphysics problems stem from the authors' research experience in the fields of electromagnetism, elasticity, thermo-elasticity and others. Finally, the implementation of the numerical technique is described in all its main components: space-time discretization, problem formulation, solution and representation of the resulting physical fields.

  20. Dynamic capabilities, Marketing Capability and Organizational Performance

    Directory of Open Access Journals (Sweden)

    Adriana Roseli Wünsch Takahashi

    2017-01-01

    Full Text Available The goal of the study is to investigate the influence of dynamic capabilities on organizational performance and the role of marketing capabilities as a mediator in this relationship in the context of private HEIs in Brazil. As a research method we carried out a survey with 316 IES and data analysis was operationalized with the technique of structural equation modeling. The results indicate that the dynamic capabilities have influence on organizational performance only when mediated by marketing ability. The marketing capability has an important role in the survival, growth and renewal on educational services offerings for HEIs in private sector, and consequently in organizational performance. It is also demonstrated that mediated relationship is more intense for HEI with up to 3,000 students and other organizational profile variables such as amount of courses, the constitution, the type of institution and type of education do not significantly alter the results.

  1. UVB in solar-simulated light causes formation of BaP-photoproducts capable of generating phosphorylated histone H2AX.

    Science.gov (United States)

    Ohnuki, Go; Toyooka, Tatsushi; Ibuki, Yuko

    2010-09-30

    Polycyclic aromatic hydrocarbons (PAHs), wide-spread mutagenic and carcinogenic environmental pollutants, are consistently exposed to sunlight in the environment. Our previous paper showed that benzo[a]pyrene (BaP) exposed to solar-simulated light (SSL) induced phosphorylation of histone H2AX (γ-H2AX) [T. Toyooka, G. Ohnuki, Y. Ibuki, Solar-simulated light-exposed benzo[a]pyrene induces phosphorylation of histone H2AX, Mutat. Res. 650 (2008) 132-139], a marker of DNA double strand breaks. In this study, we found the ultraviolet B (UVB) region of SSL to produce photomodified BaP with high cytotoxicity and the ability to generate γ-H2AX. Degradation of BaP by SSL, resulting in an increase in cytotoxicity and the generation of γ-H2AX, was decreased by UVB-masking using a glass plate. Exposure to UVB itself increased the cytotoxicity of BaP and amount of γ-H2AX generated. Other PAHs, 1,2-benzoanthracene and 1,2:5,6-dibenzoanthracene, which absorb UVB, also showed enhanced cytotoxicity and the promoted the generation of γ-H2AX after exposure to SSL, whereas naphthalene and chrysene, which have low absorption in the UVB region, did not. These findings suggested that UVB is important for the degradation of PAHs having absorbance in this region, but that the production of genotoxic intermediates during the degradation process needs to be considered. UVB is a two-edged blade in environments, effectively degrading toxic chemicals but also producing genotoxic compounds as reactive intermediates.

  2. IAC - INTEGRATED ANALYSIS CAPABILITY

    Science.gov (United States)

    Frisch, H. P.

    1994-01-01

    Integration via Mesh Interpolation Coefficients), which transforms field values from one model to another; LINK, which simplifies incorporation of user specific modules into IAC modules; and DATAPAC, the National Bureau of Standards statistical analysis package. The IAC database contains structured files which provide a common basis for communication between modules and the executive system, and can contain unstructured files such as NASTRAN checkpoint files, DISCOS plot files, object code, etc. The user can define groups of data and relations between them. A full data manipulation and query system operates with the database. The current interface modules comprise five groups: 1) Structural analysis - IAC contains a NASTRAN interface for standalone analysis or certain structural/control/thermal combinations. IAC provides enhanced structural capabilities for normal modes and static deformation analysis via special DMAP sequences. IAC 2.5 contains several specialized interfaces from NASTRAN in support of multidisciplinary analysis. 2) Thermal analysis - IAC supports finite element and finite difference techniques for steady state or transient analysis. There are interfaces for the NASTRAN thermal analyzer, SINDA/SINFLO, and TRASYS II. FEMNET, which converts finite element structural analysis models to finite difference thermal analysis models, is also interfaced with the IAC database. 3) System dynamics - The DISCOS simulation program which allows for either nonlinear time domain analysis or linear frequency domain analysis, is fully interfaced to the IAC database management capability. 4) Control analysis - Interfaces for the ORACLS, SAMSAN, NBOD2, and INCA programs allow a wide range of control system analyses and synthesis techniques. Level 2.5 includes EIGEN, which provides tools for large order system eigenanalysis, and BOPACE, which allows for geometric capabilities and finite element analysis with nonlinear material. Also included in IAC level 2.5 is SAMSAN 3.1, an

  3. 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.

  4. Use of RSM modeling for optimizing decolorization of simulated textile wastewater by Pseudomonas aeruginosa strain ZM130 capable of simultaneous removal of reactive dyes and hexavalent chromium.

    Science.gov (United States)

    Maqbool, Zahid; Hussain, Sabir; Ahmad, Tanvir; Nadeem, Habibullah; Imran, Muhammad; Khalid, Azeem; Abid, Muhammad; Martin-Laurent, Fabrice

    2016-06-01

    Remediation of colored wastewater loaded with dyes and metal ions is a matter of interest nowadays. In this study, 220 bacteria isolated from textile wastewater were tested for their potential to decolorize each of the four reactive dyes (reactive red-120, reactive black-5, reactive yellow-2, and reactive orange-16) in the presence of a mixture of four different heavy metals (Cr, Zn, Pb, Cd) commonly found in textile effluents. Among the tested bacteria, the isolate ZM130 was found to be the most efficient in decolorizing reactive dyes in the presence of the mixture of heavy metals and was identified as Pseudomonas aeruginosa strain ZM130 by 16S rRNA gene analysis. The strain ZM130 was highly effective in simultaneously removing hexavalent chromium (25 mg L(-1)) and the azo dyes (100 mg L(-1)) from the simulated wastewater even in the presence of other three heavy metals (Zn, Pb, Cd). Simultaneous removal of chromium and azo dyes ranged as 76.6-98.7 % and 51.9-91.1 %, respectively, after 180 h incubation. On the basis of quadratic polynomial equation and response surfaces given by the response surface methodology (RSM), optimal salt content, pH, carbon co-substrate content, and level of multi-metal mixtures for decolorization of reactive red-120 in a simulated textile wastewater by the strain ZM130 were predicted to be 19.8, 7.8, and 6.33 g L(-1) and a multi-metal mixture (Cr 13.10 mg L(-1), Pb 26.21 mg L(-1), Cd 13.10 mg L(-1), Zn 26.21 mg L(-1)), respectively. Moreover, the strain ZM130 also exhibited laccase and nicotinamide adenine dinucleotide (reduced)-dichlorophenolindophenol reductase (NADH-DCIP reductase) activity during the decolorization of reactive red-120. However, the laccase activity was found to be maximum in the presence of 300 mg L(-1) of the dye as compared to other concentrations. Hence, the isolation of this strain might serve as a potential bio-resource required for developing the strategies aiming at bioremediation of the

  5. Simulations

    CERN Document Server

    Ngada, N M

    2015-01-01

    The complexity and cost of building and running high-power electrical systems make the use of simulations unavoidable. The simulations available today provide great understanding about how systems really operate. This paper helps the reader to gain an insight into simulation in the field of power converters for particle accelerators. Starting with the definition and basic principles of simulation, two simulation types, as well as their leading tools, are presented: analog and numerical simulations. Some practical applications of each simulation type are also considered. The final conclusion then summarizes the main important items to keep in mind before opting for a simulation tool or before performing a simulation.

  6. Pediatric residents experience a significant decline in their response capabilities to simulated life-threatening events as their training frequency in cardiopulmonary resuscitation decreases.

    Science.gov (United States)

    Roy, Kevin M; Miller, Michael P; Schmidt, Kathleen; Sagy, Mayer

    2011-05-01

    To determine the frequency of cardiopulmonary resuscitation education using high-fidelity patient simulators during pediatric residency training. Randomized controlled trial. Suburban tertiary care children's hospital residency training program. Twenty-four second year pediatric residents. Twenty-four second year pediatric residents were randomized into two study groups, 12 residents in each. Both groups completed a formal resuscitation training course utilizing lectures, skill stations, and six scenarios on high-fidelity patient stimulators. Group A was retested on three scenarios 4 months after training and group B was similarly retested 8 months after training. Time intervals from induction of a clinical problem to its definitive management were recorded for each resident. Residents were also asked to complete surveys following each episode of training and testing. The mean time intervals, for group A, to start effective bag mask ventilation and chest compressions in response to apnea and cardiac arrest were 17.75 secs (± 3.39 secs) and 23.42 secs (± 9.33 secs), respectively. These were significantly shorter than 32.7 secs (± 18.6 secs) and 81.2 secs (± 74.9 secs), for group B, respectively (p training, when compared to 4 months after training. These results may indicate that residents require more frequent training than currently recommended.

  7. Are cranial biomechanical simulation data linked to known diets in extant taxa? A method for applying diet-biomechanics linkage models to infer feeding capability of extinct species.

    Science.gov (United States)

    Tseng, Zhijie Jack; Flynn, John J

    2015-01-01

    Performance of the masticatory system directly influences feeding and survival, so adaptive hypotheses often are proposed to explain craniodental evolution via functional morphology changes. However, the prevalence of "many-to-one" association of cranial forms and functions in vertebrates suggests a complex interplay of ecological and evolutionary histories, resulting in redundant morphology-diet linkages. Here we examine the link between cranial biomechanical properties for taxa with different dietary preferences in crown clade Carnivora, the most diverse clade of carnivorous mammals. We test whether hypercarnivores and generalists can be distinguished based on cranial mechanical simulation models, and how such diet-biomechanics linkages relate to morphology. Comparative finite element and geometric morphometrics analyses document that predicted bite force is positively allometric relative to skull strain energy; this is achieved in part by increased stiffness in larger skull models and shape changes that resist deformation and displacement. Size-standardized strain energy levels do not reflect feeding preferences; instead, caniform models have higher strain energy than feliform models. This caniform-feliform split is reinforced by a sensitivity analysis using published models for six additional taxa. Nevertheless, combined bite force-strain energy curves distinguish hypercarnivorous versus generalist feeders. These findings indicate that the link between cranial biomechanical properties and carnivoran feeding preference can be clearly defined and characterized, despite phylogenetic and allometric effects. Application of this diet-biomechanics linkage model to an analysis of an extinct stem carnivoramorphan and an outgroup creodont species provides biomechanical evidence for the evolution of taxa into distinct hypercarnivorous and generalist feeding styles prior to the appearance of crown carnivoran clades with similar feeding preferences.

  8. Are cranial biomechanical simulation data linked to known diets in extant taxa? A method for applying diet-biomechanics linkage models to infer feeding capability of extinct species.

    Directory of Open Access Journals (Sweden)

    Zhijie Jack Tseng

    Full Text Available Performance of the masticatory system directly influences feeding and survival, so adaptive hypotheses often are proposed to explain craniodental evolution via functional morphology changes. However, the prevalence of "many-to-one" association of cranial forms and functions in vertebrates suggests a complex interplay of ecological and evolutionary histories, resulting in redundant morphology-diet linkages. Here we examine the link between cranial biomechanical properties for taxa with different dietary preferences in crown clade Carnivora, the most diverse clade of carnivorous mammals. We test whether hypercarnivores and generalists can be distinguished based on cranial mechanical simulation models, and how such diet-biomechanics linkages relate to morphology. Comparative finite element and geometric morphometrics analyses document that predicted bite force is positively allometric relative to skull strain energy; this is achieved in part by increased stiffness in larger skull models and shape changes that resist deformation and displacement. Size-standardized strain energy levels do not reflect feeding preferences; instead, caniform models have higher strain energy than feliform models. This caniform-feliform split is reinforced by a sensitivity analysis using published models for six additional taxa. Nevertheless, combined bite force-strain energy curves distinguish hypercarnivorous versus generalist feeders. These findings indicate that the link between cranial biomechanical properties and carnivoran feeding preference can be clearly defined and characterized, despite phylogenetic and allometric effects. Application of this diet-biomechanics linkage model to an analysis of an extinct stem carnivoramorphan and an outgroup creodont species provides biomechanical evidence for the evolution of taxa into distinct hypercarnivorous and generalist feeding styles prior to the appearance of crown carnivoran clades with similar feeding preferences.

  9. Capabilities for Strategic Adaptation

    DEFF Research Database (Denmark)

    Distel, Andreas Philipp

    This dissertation explores capabilities that enable firms to strategically adapt to environmental changes and preserve competitiveness over time – often referred to as dynamic capabilities. While dynamic capabilities being a popular research domain, too little is known about what these capabilities...... empirical studies through the dynamic capabilities lens and develops propositions for future research. The second paper is an empirical study on the origins of firm-level absorptive capacity; it explores how organization-level antecedents, through their impact on individual-level antecedents, influence...... firms’ ability to absorb and leverage new knowledge. The third paper is an empirical study which conceptualizes top managers’ resource cognition as a managerial capability underlying firms’ resource adaptation; it empirically examines the performance implications of this capability and organizational...

  10. Optical and thermal simulation chain for LED package

    NARCIS (Netherlands)

    Tapaninen, O.; Myohanen, P.; Majanen, M.; Sitomaniemi, A.; Olkkonen, J.; Hildenbrand, V.; Gielen, A.W.J.; Mackenzie, F.V.; Barink, M.; Smilauer, V.; Patzak, B.

    2016-01-01

    This paper presents a test case for coupling two physical aspects of an LED, optical and thermal, using specific simulation models coupled through an open source platform for distributed multi-physics modelling. The glue code for coupling is written with Python programming language including routine

  11. Multi-physics corrosion modeling for sustainability assessment of steel reinforced high performance fiber reinforced cementitious composites

    DEFF Research Database (Denmark)

    Lepech, M.; Michel, Alexander; Geiker, Mette

    2016-01-01

    Using a newly developed multi-physics transport, corrosion, and cracking model, which models these phenomena as a coupled physiochemical processes, the role of HPFRCC crack control and formation in regulating steel reinforcement corrosion is investigated. This model describes transport of water...... tension-softening cementitious composites. Finally, these results are extended to provide greater insight into the assessment and design of more sustainable steel reinforced HPFRCC structures....

  12. Simulación numérica en Ingeniería y Ciencias con MATLAB + COMSOL Multiphysics

    OpenAIRE

    Ivorra, Benjamin

    2015-01-01

    En este seminario se tratan las posibles interacciones entre el entorno de programación matricial MATLAB y el software COMSOL Multiphysics, que permite resolver de forma intuitiva sistemas de ecuaciones en derivadas parciales con diversas implementaciones del método de los elementos finitos. Este tipo de ecuaciones modelan los fenómenos correspondientes a los problemas de mecánica de fluidos, transferencia de calor, electromagnetismo, etc. La posibilidad del uso combinado es importante, en pa...

  13. Advances in HYDRA and its application to simulations of Inertial Confinement Fusion targets

    Science.gov (United States)

    Marinak, M. M.; Kerbel, G. D.; Koning, J. M.; Patel, M. V.; Sepke, S. M.; Brown, P. N.; Chang, B.; Procassini, R.; Veitzer, S. A.

    2008-11-01

    We will outline new capabilities added to the HYDRA 2D/3D multiphysics ICF simulation code. These include a new SN multigroup radiation transport package (1D), constitutive models for elastic-plastic (strength) effects, and a mix model. A Monte Carlo burn package is being incorporated to model diagnostic signatures of neutrons, gamma rays and charged particles. A 3D MHD package that treats resistive MHD is available. Improvements to HYDRA's implicit Monte Carlo photonics package, including the addition of angular biasing, now enable integrated hohlraum simulations to complete in substantially shorter time. The heavy ion beam deposition package now includes a new model for ion stopping power developed by the Tech-X Corporation, with improved accuracy below the Bragg peak. Examples will illustrate HYDRA's enhanced capabilities to simulate various aspects of inertial confinement fusion targets.This work was performed under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under Contract No. DE-AC52-07NA27344. The work of Tech-X personnel was funded by the Department of Energy under Small Business Innovation Research Contract No. DE-FG02-03ER83797.

  14. Simulation of photoconductive antennas for terahertz radiation

    Directory of Open Access Journals (Sweden)

    C. A. Criollo

    2015-04-01

    Full Text Available Simulation of terahertz (THz emission based on PC antennas imposes a challenge to couple the semiconductor carrier phenomena, optical transport and the THz energy transport. In this paper a Multi-physics simulation for coupling these phenomena using COMSOL Multi-physics 4.3b is introduced. The main parameters of THz photoconductive (PC antenna as THz emitter have been reviewed and discussed. The results indicate the role of each parameter in the resulting photocurrent waveform and THz frequency: The radiated THz photocurrent waveform is determined by the photoconductive gap (the separation between the metallic electrodes, the incident laser illumination and the DC excitation voltage; while the THz frequency depends on the dipole length. The optimization of these parameters could enhance the emission. The simulations extend the advance of compact and cost-effective THz emitters.

  15. An evaluation of the performance of a WRF multi-physics ensemble for heatwave events over the city of Melbourne in southeast Australia

    Science.gov (United States)

    Imran, H. M.; Kala, J.; Ng, A. W. M.; Muthukumaran, S.

    2017-06-01

    Appropriate choice of physics options among many physics parameterizations is important when using the Weather Research and Forecasting (WRF) model. The responses of different physics parameterizations of the WRF model may vary due to geographical locations, the application of interest, and the temporal and spatial scales being investigated. Several studies have evaluated the performance of the WRF model in simulating the mean climate and extreme rainfall events for various regions in Australia. However, no study has explicitly evaluated the sensitivity of the WRF model in simulating heatwaves. Therefore, this study evaluates the performance of a WRF multi-physics ensemble that comprises 27 model configurations for a series of heatwave events in Melbourne, Australia. Unlike most previous studies, we not only evaluate temperature, but also wind speed and relative humidity, which are key factors influencing heatwave dynamics. No specific ensemble member for all events explicitly showed the best performance, for all the variables, considering all evaluation metrics. This study also found that the choice of planetary boundary layer (PBL) scheme had largest influence, the radiation scheme had moderate influence, and the microphysics scheme had the least influence on temperature simulations. The PBL and microphysics schemes were found to be more sensitive than the radiation scheme for wind speed and relative humidity. Additionally, the study tested the role of Urban Canopy Model (UCM) and three Land Surface Models (LSMs). Although the UCM did not play significant role, the Noah-LSM showed better performance than the CLM4 and NOAH-MP LSMs in simulating the heatwave events. The study finally identifies an optimal configuration of WRF that will be a useful modelling tool for further investigations of heatwaves in Melbourne. Although our results are invariably region-specific, our results will be useful to WRF users investigating heatwave dynamics elsewhere.

  16. Building Service Provider Capabilities

    DEFF Research Database (Denmark)

    Brandl, Kristin; Jaura, Manya; Ørberg Jensen, Peter D.

    In this paper we study whether and how the interaction between clients and the service providers contributes to the development of capabilities in service provider firms. In situations where such a contribution occurs, we analyze how different types of activities in the production process...... of the services, such as sequential or reciprocal task activities, influence the development of different types of capabilities. We study five cases of offshore-outsourced knowledge-intensive business services that are distinguished according to their reciprocal or sequential task activities in their production...... process. We find that clients influence the development of human capital capabilities and management capabilities in reciprocally produced services. While in sequential produced services clients influence the development of organizational capital capabilities and management capital capabilities....

  17. Developing Alliance Capabilities

    DEFF Research Database (Denmark)

    Heimeriks, Koen H.; Duysters, Geert; Vanhaverbeke, Wim

    capability. However, empirical testing in this field is scarce and little is known as to what extent different learning mechanisms are indeed useful in advancing a firm's alliance capability. This paper analyzes to what extent intra-firm learning mechanisms help firms develop their alliance capability......This paper assesses the differential performance effects of learning mechanisms on the development of alliance capabilities. Prior research has suggested that different capability levels could be identified in which specific intra-firm learning mechanisms are used to enhance a firm's alliance....... Differential learning may explain in what way firms yield superior returns from their alliances in comparison to competitors. The empirical results show that different learning mechanisms have different performance effects at different stages of the alliance capability development process. The main lesson from...

  18. 基于“模拟公司”的高职学生职业能力培养研究%Higher Vocational Capability Training Based on Simulation Company

    Institute of Scientific and Technical Information of China (English)

    穆学君; 李良敏

    2011-01-01

    Higher vocational talents training target is training high skills,high quality professional talents,while the cultivation of the students' vocational ability is the top priority in the work of the students.This article focuses on constructing the"professional simulation company teaching mode".From clearing theoretical basis of"simulation company training mode",design ideas and construction of"simulation company training mode",training mode practice of"Double Parallels,Three Levels Progression"of which students' skills training implements"elementary,middle,high"3 levels progression and students' professional quality cultivation implements"1,2,3"3 levels progression,the article positively discusses the Automobile Testing and Maintenance Technology Specialty based on"simulation company"vocational capability training mode,in practice the behavior orientation teaching idea,and on the basis of the higher vocational students' vocational capability of innovation ideas,professional education training talents training target has been achieved.%高职高专人才培养目标是培养高技能、高素质的专职人才,学生职业能力的培养是整个学生培养工作的重中之重,本论文侧重于提出构建"职业模拟公司教学模式",从明晰"模拟公司培养模式"的理论基础;"模拟公司培养模式"的设计思路与构建;践行"双线并行、三级递进"的培养模式,即:学生专业技能培养实行"初中高"三级递进和学生职业素养培养实行"一二三"三级递进等几个方面着手,积极探讨汽车检测与维修技术专业基于"模拟公司"的职业能力培养模式,在践行了行为导向教学理念的基础上,创新了高职学生职业能力培养思路,实现职业教育人才培养目标。

  19. Dynamic Capabilities and Performance

    DEFF Research Database (Denmark)

    Wilden, Ralf; Gudergan, Siegfried P.; Nielsen, Bo Bernhard

    2013-01-01

    Dynamic capabilities are widely considered to incorporate those processes that enable organizations to sustain superior performance over time. In this paper, we argue theoretically and demonstrate empirically that these effects are contingent on organizational structure and the competitive...... are contingent on the competitive intensity faced by firms. Our findings demonstrate the performance effects of internal alignment between organizational structure and dynamic capabilities, as well as the external fit of dynamic capabilities with competitive intensity. We outline the advantages of PLS...

  20. Small rover exploration capabilities

    Science.gov (United States)

    Salotti, Jean-Marc; Laithier, Corentin; Machut, Benoit; Marie, Aurélien; Bruneau, Audrey; Grömer, Gernot; Foing, Bernard H.

    2015-05-01

    For a human mission to the Moon or Mars, an important question is to determine the best strategy for the choice of surface vehicles. Recent studies suggest that the first missions to Mars will be strongly constrained and that only small unpressurized vehicles will be available. We analyze the exploration capabilities and limitations of small surface vehicles from the user perspective. Following the “human centered design” paradigm, the team focused on human systems interactions and conducted the following experiments: - Another member of our team participated in the ILEWG EuroMoonMars 2013 simulation at the Mars Desert Research Station in Utah during the same period of time. Although the possible traverses were restricted, a similar study with analog space suits and quads has been carried out. - Other experiments have been conducted in an old rock quarry close to Bordeaux, France. An expert in the use of quads for all types of terrains performed a demonstration and helped us to characterize the difficulties, the risks and advantages and drawbacks of different vehicles and tools. The vehicles that will be used on the surface of Mars have not been defined yet. Nevertheless, the results of our project already show that using a light and unpressurized vehicle (in the order of 150 kg) for the mobility on the Martian surface can be a true advantage. Part of the study was dedicated to the search for appropriate tools that could be used to make the vehicles easier to handle, safer to use and more efficient in the field to cross an obstacle. The final recommendation is to use winches and ramps, which already are widely used by quad drivers. We report on the extension of the reachable areas if such tools were available. This work has been supported by ILEWG, EuroMoonMars and the Austrian Space Forum (OEWF).

  1. Flex: RSRE's capability computer

    Science.gov (United States)

    Foster, J. M.

    The Flex capability based computer architecture is described. It supports a multilanguage environment, and compilers for ALGOL 168 and PASCAL exist; an Ada compiler is being completed. The idea of capabilities is used on backing store as well as main store, so that all kinds of structured object which can be held in main store can also be held on any of the packing stores with the same degree of protection. Capabilities are used across a network of Flex computers, so that capabilities for data in one machine may be passed to and held in another. Flex uses true procedure values in the sense of Landin (1964).

  2. Integrated Process Capability Analysis

    Institute of Scientific and Technical Information of China (English)

    Chen; H; T; Huang; M; L; Hung; Y; H; Chen; K; S

    2002-01-01

    Process Capability Analysis (PCA) is a powerful too l to assess the ability of a process for manufacturing product that meets specific ations. The larger process capability index implies the higher process yield, a nd the larger process capability index also indicates the lower process expected loss. Chen et al. (2001) has applied indices C pu, C pl, and C pk for evaluating the process capability for a multi-process product wi th smaller-the-better, larger-the-better, and nominal-the-best spec...

  3. Simulation of the impact of 3-D porosity distribution in metallic U-10Zr fuels

    Science.gov (United States)

    Yun, Di; Yacout, Abdellatif M.; Stan, Marius; Bauer, Theodore H.; Wright, Arthur E.

    2014-05-01

    Evolution of porosity generated in metallic U-Zr fuel irradiated in fast spectrum reactors leads to changes in fuel properties and impacts important phenomena such as heat transport and constituent redistribution. The porosity is generated as a result of the accumulation of fission gases and is affected by the possible bond sodium infiltration into the fuel. Typically, the impact of porosity development on properties, such as thermal conductivity, is accounted for through empirical correlations that are dependent on porosity and infiltrated sodium fractions. Currently available simulation tools make it possible to take into account fuel 3-D porosity distributions, potentially eliminating the need for such correlations. This development allows for a more realistic representation of the porosity evolution in metallic fuel and creates a framework for truly mechanistic fuel development models. In this work, COMSOL multi-physics simulation platform is used to model 3-D porosity distributions and simulate heat transport in metallic U-10Zr fuel. Available experimental data regarding microstructural evolution of fuel that was irradiated in EBR-II and associated phase stability information are used to guide the simulation. The impact of changes in porosity characteristics on material properties is estimated and the results are compared with calculated temperature distributions. The simulations demonstrate the developed capability and importance of accounting for detailed porosity distribution features for accurate fuel performance evaluation.

  4. Simulations of Interdigitated Electrode Interactions with Gold Nanoparticles for Impedance-Based Biosensing Applications

    Directory of Open Access Journals (Sweden)

    Scott MacKay

    2015-09-01

    Full Text Available In this paper, we describe a point-of-care biosensor design. The uniqueness of our design is in its capability for detecting a wide variety of target biomolecules and the simplicity of nanoparticle enhanced electrical detection. The electrical properties of interdigitated electrodes (IDEs and the mechanism for gold nanoparticle-enhanced impedance-based biosensor systems based on these electrodes are simulated using COMSOL Multiphysics software. Understanding these properties and how they can be affected is vital in designing effective biosensor devices. Simulations were used to show electrical screening develop over time for IDEs in a salt solution, as well as the electric field between individual digits of electrodes. Using these simulations, it was observed that gold nanoparticles bound closely to IDEs can lower the electric field magnitude between the digits of the electrode. The simulations are also shown to be a useful design tool in optimizing sensor function. Various different conditions, such as electrode dimensions and background ion concentrations, are shown to have a significant impact on the simulations.

  5. Simulations of Interdigitated Electrode Interactions with Gold Nanoparticles for Impedance-Based Biosensing Applications.

    Science.gov (United States)

    MacKay, Scott; Hermansen, Peter; Wishart, David; Chen, Jie

    2015-09-02

    In this paper, we describe a point-of-care biosensor design. The uniqueness of our design is in its capability for detecting a wide variety of target biomolecules and the simplicity of nanoparticle enhanced electrical detection. The electrical properties of interdigitated electrodes (IDEs) and the mechanism for gold nanoparticle-enhanced impedance-based biosensor systems based on these electrodes are simulated using COMSOL Multiphysics software. Understanding these properties and how they can be affected is vital in designing effective biosensor devices. Simulations were used to show electrical screening develop over time for IDEs in a salt solution, as well as the electric field between individual digits of electrodes. Using these simulations, it was observed that gold nanoparticles bound closely to IDEs can lower the electric field magnitude between the digits of the electrode. The simulations are also shown to be a useful design tool in optimizing sensor function. Various different conditions, such as electrode dimensions and background ion concentrations, are shown to have a significant impact on the simulations.

  6. Solution of the KdV Equation Based on COMSOL Multiphysics%基于COMSOL Multiphysics求解KdV方程

    Institute of Scientific and Technical Information of China (English)

    糜凯华

    2014-01-01

    In order to obtain numerical solutions of the KdV equation,COMSOL Multiphysics software based on finite element method established a finite element model and solved the distribution of solitary waves at various points in time. The results can study the propagation of solitary waves. Simulation results indicate that the soli-tary wave does not occur in isolation. Solitary waves can be found within a certain space where collisions occur as well as reproduced by representing as a three dimensional map distribution. Two different speed and ampli-tude solitons collided and did not affect each other.%为了得到KdV方程的数值解,基于有限单元法的COMSOL Multiphysics软件建立有限元模型并求解孤立波在各个时间点的分布情况,以研究孤立波的传播特性。数值模拟结果表明:孤立波不会发生消散,以三维图的分布形式表示,可以发现孤立子在一定的空间内会发生碰撞以及发生重现,也即两个不同速度和振幅的孤子相互碰撞、相互穿过,互相之间没有影响。

  7. Multi-physical model of cation and water transport in ionic polymer-metal composite sensors

    Science.gov (United States)

    Zhu, Zicai; Chang, Longfei; Horiuchi, Tetsuya; Takagi, Kentaro; Aabloo, Alvo; Asaka, Kinji

    2016-03-01

    Ion-migration based electrical potential widely exists not only in natural systems but also in ionic polymer materials. We presented a multi-physical model and investigated the transport process of cation and water of ionic polymer-metal composites based on our thorough understanding on the ionic sensing mechanisms in this paper. The whole transport process was depicted by transport equations concerning convection flux under the total pressure gradient, electrical migration by the built-in electrical field, and the inter-coupling effect between cation and water. With numerical analysis, the influence of critical material parameters, the elastic modulus Ewet, the hydraulic permeability coefficient K, the diffusion coefficient of cation dII and water dWW, and the drag coefficient of water ndW, on the distribution of cation and water was investigated. It was obtained how these parameters correlate to the voltage characteristics (both magnitude and response speed) under a step bending. Additionally, it was found that the effective relative dielectric constant ɛr has little influence on the voltage but is positively correlated to the current. With a series of optimized parameters, the predicted voltage agreed with the experimental results well, which validated our model. Based on our physical model, it was suggested that an ionic polymer sensor can benefit from a higher modulus Ewet, a higher coefficient K and a lower coefficient dII, and a higher constant ɛr.

  8. Research on Structural Safety of the Stratospheric Airship Based on Multi-Physics Coupling Calculation

    Science.gov (United States)

    Ma, Z.; Hou, Z.; Zang, X.

    2015-09-01

    As a large-scale flexible inflatable structure by a huge inner lifting gas volume of several hundred thousand cubic meters, the stratospheric airship's thermal characteristic of inner gas plays an important role in its structural performance. During the floating flight, the day-night variation of the combined thermal condition leads to the fluctuation of the flow field inside the airship, which will remarkably affect the pressure acted on the skin and the structural safety of the stratospheric airship. According to the multi-physics coupling mechanism mentioned above, a numerical procedure of structural safety analysis of stratospheric airships is developed and the thermal model, CFD model, finite element code and criterion of structural strength are integrated. Based on the computation models, the distributions of the deformations and stresses of the skin are calculated with the variation of day-night time. The effects of loads conditions and structural configurations on the structural safety of stratospheric airships in the floating condition are evaluated. The numerical results can be referenced for the structural design of stratospheric airships.

  9. Investigation on stresses of superconductors under pulsed magnetic fields based on multiphysics model

    Science.gov (United States)

    Yang, Xiaobin; Li, Xiuhong; He, Yafeng; Wang, Xiaojun; Xu, Bo

    2017-04-01

    A multiphysics model for the numerical computation of stresses, trapped field and temperature distribution of a infinite long superconducting cylinder is proposed, based on which the stresses, including the thermal stresses and mechanical stresses due to Lorentz force, and trapped fields in the superconductor subjected to pulsed magnetic fields are analyzed. By comparing the results under pulsed magnetic fields with different pulse durations, it is found that the both the mechanical stress due to the electromagnetic force and the thermal stress due to temperature gradient contribute to the total stress level in the superconductor. For pulsed magnetic field with short durations, the thermal stress is the dominant contribution to the total stress, because the heat generated by AC-loss builds up significant temperature gradient in such short durations. However, for a pulsed field with a long duration the gradient of temperature and flux, as well as the maximal tensile stress, are much smaller. And the results of this paper is meaningful for the design and manufacture of superconducting permanent magnets.

  10. Investigation on stresses of superconductors under pulsed magnetic fields based on multiphysics model

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiaobin, E-mail: yangxb@lzu.edu.cn; Li, Xiuhong; He, Yafeng; Wang, Xiaojun; Xu, Bo

    2017-04-15

    Highlights: • The differential equation including temperature and magnetic field was derived for a long cylindrical superconductor. • Thermal stress and electromagnetic stress were studied at the same time under pulse field magnetizing. • The distributions of the magnetic field, the temperature and stresses are studied and compared for two pulse fields of the different duration. • The Role thermal stress and electromagnetic stress play in the process of pulse field magnetizing is discussed. - Abstract: A multiphysics model for the numerical computation of stresses, trapped field and temperature distribution of a infinite long superconducting cylinder is proposed, based on which the stresses, including the thermal stresses and mechanical stresses due to Lorentz force, and trapped fields in the superconductor subjected to pulsed magnetic fields are analyzed. By comparing the results under pulsed magnetic fields with different pulse durations, it is found that the both the mechanical stress due to the electromagnetic force and the thermal stress due to temperature gradient contribute to the total stress level in the superconductor. For pulsed magnetic field with short durations, the thermal stress is the dominant contribution to the total stress, because the heat generated by AC-loss builds up significant temperature gradient in such short durations. However, for a pulsed field with a long duration the gradient of temperature and flux, as well as the maximal tensile stress, are much smaller. And the results of this paper is meaningful for the design and manufacture of superconducting permanent magnets.

  11. A liquid metal-based structurally embedded vascular antenna: I. Concept and multiphysical modeling

    Science.gov (United States)

    Hartl, D. J.; Frank, G. J.; Huff, G. H.; Baur, J. W.

    2017-02-01

    This work proposes a new concept for a reconfigurable structurally embedded vascular antenna (SEVA). The work builds on ongoing research of structurally embedded microvascular systems in laminated structures for thermal transport and self-healing and on studies of non-toxic liquid metals for reconfigurable electronics. In the example design, liquid metal-filled channels in a laminated composite act as radiating elements for a high-power planar zig-zag wire log periodic dipole antenna. Flow of liquid metal through the channels is used to limit the temperature of the composite in which the antenna is embedded. A multiphysics engineering model of the transmitting antenna is formulated that couples the electromagnetic, fluid, thermal, and mechanical responses. In part 1 of this two-part work, it is shown that the liquid metal antenna is highly reconfigurable in terms of its electromagnetic response and that dissipated thermal energy generated during high power operation can be offset by the action of circulating or cyclically replacing the liquid metal such that heat is continuously removed from the system. In fact, the SEVA can potentially outperform traditional copper-based antennas in high-power operational configurations. The coupled engineering model is implemented in an automated framework and a design of experiment study is performed to quantify first-order design trade-offs in this multifunctional structure. More rigorous design optimization is addressed in part 2.

  12. Propagation of neutron-reaction uncertainties through multi-physics models of novel LWR's

    Directory of Open Access Journals (Sweden)

    Hernandez-Solis Augusto

    2017-01-01

    Full Text Available The novel design of the renewable boiling water reactor (RBWR allows a breeding ratio greater than unity and thus, it aims at providing for a self-sustained fuel cycle. The neutron reactions that compose the different microscopic cross-sections and angular distributions are uncertain, so when they are employed in the determination of the spatial distribution of the neutron flux in a nuclear reactor, a methodology should be employed to account for these associated uncertainties. In this work, the Total Monte Carlo (TMC method is used to propagate the different neutron-reactions (as well as angular distributions covariances that are part of the TENDL-2014 nuclear data (ND library. The main objective is to propagate them through coupled neutronic and thermal-hydraulic models in order to assess the uncertainty of important safety parameters related to multi-physics, such as peak cladding temperature along the axial direction of an RBWR fuel assembly. The objective of this study is to quantify the impact that ND covariances of important nuclides such as U-235, U-238, Pu-239 and the thermal scattering of hydrogen in H2O have in the deterministic safety analysis of novel nuclear reactors designs.

  13. Multiobject Reliability Analysis of Turbine Blisk with Multidiscipline under Multiphysical Field Interaction

    Directory of Open Access Journals (Sweden)

    Chun-Yi Zhang

    2015-01-01

    Full Text Available To study accurately the influence of the deformation, stress, and strain of turbine blisk on the performance of aeroengine, the comprehensive reliability analysis of turbine blisk with multiple disciplines and multiple objects was performed based on multiple response surface method (MRSM and fluid-thermal-solid coupling technique. Firstly, the basic thought of MRSM was introduced. And then the mathematical model of MRSM was established with quadratic polynomial. Finally, the multiple reliability analyses of deformation, stress, and strain of turbine blisk were completed under multiphysical field coupling by the MRSM, and the comprehensive performance of turbine blisk was evaluated. From the reliability analysis, it is demonstrated that the reliability degrees of the deformation, stress, and strain for turbine blisk are 0.9942, 0.9935, 0.9954, and 0.9919, respectively, when the allowable deformation, stress, and strain are 3.7 × 10−3 m, 1.07 × 109 Pa, and 1.12 × 10−2 m/m, respectively; besides, the comprehensive reliability degree of turbine blisk is 0.9919, which basically satisfies the engineering requirement of aeroengine. The efforts of this paper provide a promising approach method for multidiscipline multiobject reliability analysis.

  14. Coupling between a multi-physics workflow engine and an optimization framework

    Science.gov (United States)

    Di Gallo, L.; Reux, C.; Imbeaux, F.; Artaud, J.-F.; Owsiak, M.; Saoutic, B.; Aiello, G.; Bernardi, P.; Ciraolo, G.; Bucalossi, J.; Duchateau, J.-L.; Fausser, C.; Galassi, D.; Hertout, P.; Jaboulay, J.-C.; Li-Puma, A.; Zani, L.

    2016-03-01

    A generic coupling method between a multi-physics workflow engine and an optimization framework is presented in this paper. The coupling architecture has been developed in order to preserve the integrity of the two frameworks. The objective is to provide the possibility to replace a framework, a workflow or an optimizer by another one without changing the whole coupling procedure or modifying the main content in each framework. The coupling is achieved by using a socket-based communication library for exchanging data between the two frameworks. Among a number of algorithms provided by optimization frameworks, Genetic Algorithms (GAs) have demonstrated their efficiency on single and multiple criteria optimization. Additionally to their robustness, GAs can handle non-valid data which may appear during the optimization. Consequently GAs work on most general cases. A parallelized framework has been developed to reduce the time spent for optimizations and evaluation of large samples. A test has shown a good scaling efficiency of this parallelized framework. This coupling method has been applied to the case of SYCOMORE (SYstem COde for MOdeling tokamak REactor) which is a system code developed in form of a modular workflow for designing magnetic fusion reactors. The coupling of SYCOMORE with the optimization platform URANIE enables design optimization along various figures of merit and constraints.

  15. Specification of requirements for the virtual environment for reactor applications simulation environment

    Energy Technology Data Exchange (ETDEWEB)

    Hess, S. M. [Electric Power Research Inst., 300 Baywood Road, West Chester, PA 19382 (United States); Pytel, M. [Electric Power Research Inst., 3420 Hillview Avenue, Palo Alto, CA 94304 (United States)

    2012-07-01

    In 2010, the United States Dept. of Energy initiated a research and development effort to develop modern modeling and simulation methods that could utilize high performance computing capabilities to address issues important to nuclear power plant operation, safety and sustainability. To respond to this need, a consortium of national laboratories, academic institutions and industry partners (the Consortium for Advanced Simulation of Light Water Reactors - CASL) was formed to develop an integrated Virtual Environment for Reactor Applications (VERA) modeling and simulation capability. A critical element for the success of the CASL research and development effort was the development of an integrated set of overarching requirements that provides guidance in the planning, development, and management of the VERA modeling and simulation software. These requirements also provide a mechanism from which the needs of a broad array of external CASL stakeholders (e.g. reactor / fuel vendors, plant owner / operators, regulatory personnel, etc.) can be identified and integrated into the VERA development plans. This paper presents an overview of the initial set of requirements contained within the VERA Requirements Document (VRD) that currently is being used to govern development of the VERA software within the CASL program. The complex interdisciplinary nature of these requirements together with a multi-physics coupling approach to realize a core simulator capability pose a challenge to how the VRD should be derived and subsequently revised to accommodate the needs of different stakeholders. Thus, the VRD is viewed as an evolving document that will be updated periodically to reflect the changing needs of identified CASL stakeholders and lessons learned during the progress of the CASL modeling and simulation program. (authors)

  16. Telematics Options and Capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Hodge, Cabell [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-05

    This presentation describes the data tracking and analytical capabilities of telematics devices. Federal fleet managers can use the systems to keep their drivers safe, maintain a fuel efficient fleet, ease their reporting burden, and save money. The presentation includes an example of how much these capabilities can save fleets.

  17. Simulation of A Main Steam Line Break Accident Using the Coupled 'System Thermal-Hydraulics, 3D reactor Kinetics, and Hot Channel' Analysis Capability of MARS 3.0

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Jae Jun; Chung, Bub Dong

    2005-09-15

    For realistic analysis of thermal-hydraulics (T-H) transients in light water reactors, KAERI has developed the best-estimate T-H system code, MARS. The code has been improved from the consolidated version of the RELAP5/MOD3 and COBRA-TF codes. Then, the MARS code was coupled with a three-dimensional (3-D) reactor kinetics code, MASTER. This coupled calculation feature, in conjunction with the existing hot channel analysis capabilities of the MARS and MASTER codes, allows for more realistic simulations of nuclear system transients. In this work, a main steam line break (MSLB) accident is simulated using the coupled 'system T-H, 3-D reactor kinetics, and hot channel analysis' feature of the MARS code. Two coupled calculations are performed for demonstration. First, a coupled calculation of the 'system T-H and 3-D reactor kinetics' with a refined core T-H nodalization is carried out to obtain global core power and local departure from nucleate boiling (DNB) ratio (DNBR) behaviors. Next, for a more accurate DNBR prediction, another coupled calculation with subchannel meshes for the hot channels is performed. The results of the coupled calculations are very reasonable and consistent so that these can be used to remove the excessive conservatism in the conventional safety analysis.

  18. Overview of ASC Capability Computing System Governance Model

    Energy Technology Data Exchange (ETDEWEB)

    Doebling, Scott W. [Los Alamos National Laboratory

    2012-07-11

    This document contains a description of the Advanced Simulation and Computing Program's Capability Computing System Governance Model. Objectives of the Governance Model are to ensure that the capability system resources are allocated on a priority-driven basis according to the Program requirements; and to utilize ASC Capability Systems for the large capability jobs for which they were designed and procured.

  19. RF Wave Simulation Using the MFEM Open Source FEM Package

    Science.gov (United States)

    Stillerman, J.; Shiraiwa, S.; Bonoli, P. T.; Wright, J. C.; Green, D. L.; Kolev, T.

    2016-10-01

    A new plasma wave simulation environment based on the finite element method is presented. MFEM, a scalable open-source FEM library, is used as the basis for this capability. MFEM allows for assembling an FEM matrix of arbitrarily high order in a parallel computing environment. A 3D frequency domain RF physics layer was implemented using a python wrapper for MFEM and a cold collisional plasma model was ported. This physics layer allows for defining the plasma RF wave simulation model without user knowledge of the FEM weak-form formulation. A graphical user interface is built on πScope, a python-based scientific workbench, such that a user can build a model definition file interactively. Benchmark cases have been ported to this new environment, with results being consistent with those obtained using COMSOL multiphysics, GENRAY, and TORIC/TORLH spectral solvers. This work is a first step in bringing to bear the sophisticated computational tool suite that MFEM provides (e.g., adaptive mesh refinement, solver suite, element types) to the linear plasma-wave interaction problem, and within more complicated integrated workflows, such as coupling with core spectral solver, or incorporating additional physics such as an RF sheath potential model or kinetic effects. USDoE Awards DE-FC02-99ER54512, DE-FC02-01ER54648.

  20. Design and Simulation of an Electrothermal Actuator Based Rotational Drive

    Science.gov (United States)

    Beeson, Sterling; Dallas, Tim

    2008-10-01

    As a participant in the Micro and Nano Device Engineering (MANDE) Research Experience for Undergraduates program at Texas Tech University, I learned how MEMS devices operate and the limits of their operation. Using specialized AutoCAD-based design software and the ANSYS simulation program, I learned the MEMS fabrication process used at Sandia National Labs, the design limitations of this process, the abilities and drawbacks of micro devices, and finally, I redesigned a MEMS device called the Chevron Torsional Ratcheting Actuator (CTRA). Motion is achieved through electrothermal actuation. The chevron (bent-beam) actuators cause a ratcheting motion on top of a hub-less gear so that as voltage is applied the CTRA spins. The voltage applied needs to be pulsed and the frequency of the pulses determine the angular frequency of the device. The main objective was to design electromechanical structures capable of transforming the electrical signals into mechanical motion without overheating. The design was optimized using finite element analysis in ANSYS allowing multi-physics simulations of our model system.

  1. Alya: Towards Exascale for Engineering Simulation Codes

    CERN Document Server

    Vazquez, Mariano; Koric, Seid; Artigues, Antoni; Aguado-Sierra, Jazmin; Aris, Ruth; Mira, Daniel; Calmet, Hadrien; Cucchietti, Fernando; Owen, Herbert; Taha, Ahmed; Cela, Jose Maria

    2014-01-01

    Alya is the BSC in-house HPC-based multi-physics simulation code. It is designed from scratch to run efficiently in parallel supercomputers, solving coupled problems. The target domain is engineering, with all its particular features: complex geome- tries and unstructured meshes, coupled multi-physics with exotic coupling schemes and Physical models, ill-posed problems, flexibility needs for rapidly including new models, etc. Since its conception in 2004, Alya has shown scaling behaviour in an increasing number of cores. In this paper, we present its performance up to 100.000 cores in Blue Waters, the NCSA supercomputer. The selected tests are representative of the engineering world, all the problematic features included: incompressible flow in a hu- man respiratory system, low Mach combustion problem in a kiln furnace and coupled electro-mechanical problem in a heart. We show scalability plots for all cases, discussing all the aspects of such kind of simulations, including solvers convergence.

  2. Capabilities for Strategic Adaptation

    DEFF Research Database (Denmark)

    Distel, Andreas Philipp

    organizational conditions, such as organizational design, support the emergence and performance of such capabilities. In detail, the dissertation consists of three self-contained research papers. The first paper is a systematic, multilevel review of the innovation literature; it reinterprets evidence from prior...... firms’ ability to absorb and leverage new knowledge. The third paper is an empirical study which conceptualizes top managers’ resource cognition as a managerial capability underlying firms’ resource adaptation; it empirically examines the performance implications of this capability and organizational...... empirical studies through the dynamic capabilities lens and develops propositions for future research. The second paper is an empirical study on the origins of firm-level absorptive capacity; it explores how organization-level antecedents, through their impact on individual-level antecedents, influence...

  3. Defence Capability Plan 2009

    Science.gov (United States)

    2009-01-01

    financed lease , or elements of both. Background Initially, an improved rotary wing training capability was to be provided under two projects – Phase 7A...Destroyer (AWD), Super Hornet and New Air Combat Capability (NACC). Through-life Support The Commonwealth seeks a ‘ turnkey ’ service providing aerial...combination: > Commercial- and/or Military-off-the-Shelf; or > open tender for ADF ownership or lease . Through-life Support Depending on the procurement (ADF

  4. A self-taught artificial agent for multi-physics computational model personalization.

    Science.gov (United States)

    Neumann, Dominik; Mansi, Tommaso; Itu, Lucian; Georgescu, Bogdan; Kayvanpour, Elham; Sedaghat-Hamedani, Farbod; Amr, Ali; Haas, Jan; Katus, Hugo; Meder, Benjamin; Steidl, Stefan; Hornegger, Joachim; Comaniciu, Dorin

    2016-12-01

    Personalization is the process of fitting a model to patient data, a critical step towards application of multi-physics computational models in clinical practice. Designing robust personalization algorithms is often a tedious, time-consuming, model- and data-specific process. We propose to use artificial intelligence concepts to learn this task, inspired by how human experts manually perform it. The problem is reformulated in terms of reinforcement learning. In an off-line phase, Vito, our self-taught artificial agent, learns a representative decision process model through exploration of the computational model: it learns how the model behaves under change of parameters. The agent then automatically learns an optimal strategy for on-line personalization. The algorithm is model-independent; applying it to a new model requires only adjusting few hyper-parameters of the agent and defining the observations to match. The full knowledge of the model itself is not required. Vito was tested in a synthetic scenario, showing that it could learn how to optimize cost functions generically. Then Vito was applied to the inverse problem of cardiac electrophysiology and the personalization of a whole-body circulation model. The obtained results suggested that Vito could achieve equivalent, if not better goodness of fit than standard methods, while being more robust (up to 11% higher success rates) and with faster (up to seven times) convergence rate. Our artificial intelligence approach could thus make personalization algorithms generalizable and self-adaptable to any patient and any model. Copyright © 2016. Published by Elsevier B.V.

  5. Coupled multiphysics, barrier localization, and critical radius effects in embedded nanowire superlattices

    Science.gov (United States)

    Prabhakar, Sanjay; Melnik, Roderick; Bonilla, Luis L.

    2013-06-01

    The new contribution of this paper is to develop a cylindrical representation of an already known multiphysics model for embedded nanowire superlattices (NWSLs) of wurtzite structure that includes a coupled, strain dependent 8-band k .p Hamiltonian in cylindrical coordinates and investigate the influence of coupled piezo-electromechanical effects on the barrier localization and critical radius in such NWSLs. The coupled piezo-electromechanical model for semiconductor materials takes into account the strain, piezoelectric effects, and spontaneous polarization. Based on the developed 3D model, the band structures of electrons (holes) obtained from results of modeling in Cartesian coordinates are in good agreement with those values obtained from our earlier developed 2D model in cylindrical coordinates. Several parameters such as lattice mismatch, piezo-electric fields, valence, and conduction band offsets at the heterojunction of AlxGa1-xN/GaN superlattice can be varied as a function of the Al mole fraction. When the band offsets at the heterojunction of AlxGa1-xN/GaN are very small and the influence of the piezo-electromechanical effects can be minimized, then the barrier material can no longer be treated as an infinite potential well. In this situation, it is possible to visualize the penetration of the Bloch wave function into the barrier material that provides an estimation of critical radii of NWSLs. In this case, the NWSLs can act as inversion layers. Finally, we investigate the influence of symmetry of the square and cylindrical NWSLs on the band structures of electrons in the conduction band.

  6. Flexible Implementation of Multiphysics and Discretizations in PyLith Crustal Deformation Modeling Software

    Science.gov (United States)

    Aagaard, B.; Knepley, M.; Williams, C. A.

    2016-12-01

    We are creating a flexible implementation of multiphysics and finite-element discretizations in PyLith, a community, open-source code (http://geodynamics.org/cig/software/pylith/) for modeling quasi-static and dynamic crustal deformation with an emphasis on earthquake faulting. The goals include expanding the current suite of elastic, viscoelastic, and elastoplastic bulk rheologies to include poroelasticity, thermoelasticity, and incompressible elasticity. We cast the governing equations in a form that involves the product of the finite-element basis function or its derivatives with pointwise functions that look very much like the strong form of the governing equation. This allows the finite-element integration to be decomposed into a routine for the numerical integration over cells and boundaries of the finite-element mesh and simple routines implementing the physics (pointwise functions). The finite-element integration routine works in any spatial dimension with an arbitrary number of physical fields (e.g., displacement, temperature, and fluid pressure). It also makes it much easier optimize the finite-element integrations for proper vectorization, tiling, and other traversal optimization on multiple architectures (e.g., CUDA and OpenCL) independent of the pointwise functions. Users can easily extend the code by adding new routines for the pointwise functions to implement different rheologies and/or governing equations. Tight integration with the Portable, Extensible Toolkit for Scientific Computation (PETSc) provides support for a wide range of linear and nonlinear solvers and time-stepping algorithms so that a wide variety of governing equations can be solved efficiently.

  7. Design of a Resistively Heated Thermal Hydraulic Simulator for Nuclear Rocket Reactor Cores

    Science.gov (United States)

    Litchford, Ron J.; Foote, John P.; Ramachandran, Narayanan; Wang, Ten-See; Anghaie, Samim

    2007-01-01

    A preliminary design study is presented for a non-nuclear test facility which uses ohmic heating to replicate the thermal hydraulic characteristics of solid core nuclear reactor fuel element passages. The basis for this testing capability is a recently commissioned nuclear thermal rocket environments simulator, which uses a high-power, multi-gas, wall-stabilized constricted arc-heater to produce high-temperature pressurized hydrogen flows representative of reactor core environments, excepting radiation effects. Initially, the baseline test fixture for this non-nuclear environments simulator was configured for long duration hot hydrogen exposure of small cylindrical material specimens as a low cost means of evaluating material compatibility. It became evident, however, that additional functionality enhancements were needed to permit a critical examination of thermal hydraulic effects in fuel element passages. Thus, a design configuration was conceived whereby a short tubular material specimen, representing a fuel element passage segment, is surrounded by a backside resistive tungsten heater element and mounted within a self-contained module that inserts directly into the baseline test fixture assembly. With this configuration, it becomes possible to create an inward directed radial thermal gradient within the tubular material specimen such that the wall-to-gas heat flux characteristics of a typical fuel element passage are effectively simulated. The results of a preliminary engineering study for this innovative concept are fully summarized, including high-fidelity multi-physics thermal hydraulic simulations and detailed design features.

  8. Structural Capability of an Organization toward Innovation Capability

    DEFF Research Database (Denmark)

    Nielsen, Susanne Balslev; Momeni, Mostafa

    2016-01-01

    competitive advantage in the organizations is the innovation capability. The innovation capability is associated with other organizational capabilities, and many organizations have focused on the need to identify innovation capabilities.This research focuses on recognition of the structural aspect...... of innovation capability and proposes a conceptual framework based on a Qualitative Meta Synthesis of academic literature on organizations innovation capability. This is proposed for the development of the concept of innovation capability in the organizations and this paper includes an expert based validation...... Capability and Structural Capability. Also, it offers the most important components and indices which directly influence and are related to the structural capability of innovation capability....

  9. Dynamic Fracture Simulations of Explosively Loaded Cylinders

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, Carly W. [Univ. of California, Davis, CA (United States). Dept. of Civil and Environmental Engineering; Goto, D. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-11-30

    This report documents the modeling results of high explosive experiments investigating dynamic fracture of steel (AerMet® 100 alloy) cylinders. The experiments were conducted at Lawrence Livermore National Laboratory (LLNL) during 2007 to 2008 [10]. A principal objective of this study was to gain an understanding of dynamic material failure through the analysis of hydrodynamic computer code simulations. Two-dimensional and three-dimensional computational cylinder models were analyzed using the ALE3D multi-physics computer code.

  10. 基于COMSOL Multiphysics超声波电机的谐振特性分析%The Resonant Feature Analysis of Ultrasonic Motor Based on COMSOL Multiphysics

    Institute of Scientific and Technical Information of China (English)

    吕琼莹; 杨艳; 焦海坤; 张志杰

    2012-01-01

    基于COMSOL Multiphysics对超声波电机压电振子谐振特性进行了理论分析,建立了超声波电机压电振子的实体模型,仿真计算出了压电振子的谐振频率,确定超声波电动机的最佳工作频段,提出了电机与驱动电路匹配方法.试验结果表明:当对压电振子施加幅值为100 V的激励电压后,软件分析和数学计算基本一致,可见仿真分析方法的可行性,为研究超声波电机谐振特性提供了一种简便的计算方法.%The resonant feature of the piezoelectric resonator of ultrasonic motor is analyzed based on the COMSOL Multiphysics in this paper. The entity model of the piezoelectric resonator of ultrasonic motor has been established. The resonant frequency of the piezoelectric resonator was calculated by the simulation and the best operating frequency range of ultrasonic motor was determined. The matching method between the motor and the driving circuit was proposed. The test results showed that when an exciting voltage with the amplitude of 100 V was applied to the piezoelectric resonator, the software analysis results were basically consistent with the mathematical calculation thus indicated that the method of simulation analysis was feasible. This provides a simple calculation method for the study of the resonant feature of ultrasonic motor.

  11. Final Report for Project "Framework Application for Core-Edge Transport Simulations (FACETS)"

    Energy Technology Data Exchange (ETDEWEB)

    Estep, Donald [Colorado State University

    2014-01-17

    This is the final report for the Colorado State University Component of the FACETS Project. FACETS was focused on the development of a multiphysics, parallel framework application that could provide the capability to enable whole-device fusion reactor modeling and, in the process, the development of the modeling infrastructure and computational understanding needed for ITER. It was intended that FACETS be highly flexible, through the use of modern computational methods, including component technology and object oriented design, to facilitate switching from one model to another for a given aspect of the physics, and making it possible to use simplified models for rapid turnaround or high-fidelity models that will take advantage of the largest supercomputer hardware. FACETS was designed in a heterogeneous parallel context, where different parts of the application can take advantage through parallelism based on task farming, domain decomposition, and/or pipelining as needed and applicable. As with all fusion simulations, an integral part of the FACETS project was treatment of the coupling of different physical processes at different scales interacting closely. A primary example for the FACETS project is the coupling of existing core and edge simulations, with the transport and wall interactions described by reduced models. However, core and edge simulations themselves involve significant coupling of different processes with large scale differences. Numerical treatment of coupling is impacted by a number of factors including, scale differences, form of information transferred between processes, implementation of solvers for different codes, and high performance computing concerns. Operator decomposition involving the computation of the individual processes individually using appropriate simulation codes and then linking/synchronizing the component simulations at regular points in space and time, is the defacto approach to high performance simulation of multiphysics

  12. Experimental Characterisation and Multi-Physic Modelling of Direct Bonding Mechanical Behaviour: Application to Spatial Optical Systems

    Science.gov (United States)

    Cocheteau, N.; Maurel-Pantel, A.; Lebon, F.; Rosu, I.; Ait-Zaid, S.; Savin de Larclause, I.; Salaun, Y.

    2014-06-01

    Direct bonding is a well-known process. However in order to use this process in spatial instrument fabrication the mechanical resistance needs to be quantified precisely. In order to improve bonded strength, optimal parameters of the process are found by studying the influence of annealing time, temperature and roughness which are studied using three experimental methods: double shear, cleavage and wedge tests. Those parameters are chosen thanks to the appearance of time/temperature equivalence. All results brought out the implementation of a multi-physic model to predict the mechanical behavior of direct bonding interface.

  13. Kokkos? Task DAG Capabilities.

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, Harold C.; Ibanez, Daniel Alejandro

    2017-09-01

    This report documents the ASC/ATDM Kokkos deliverable "Production Portable Dy- namic Task DAG Capability." This capability enables applications to create and execute a dynamic task DAG ; a collection of heterogeneous computational tasks with a directed acyclic graph (DAG) of "execute after" dependencies where tasks and their dependencies are dynamically created and destroyed as tasks execute. The Kokkos task scheduler executes the dynamic task DAG on the target execution resource; e.g. a multicore CPU, a manycore CPU such as Intel's Knights Landing (KNL), or an NVIDIA GPU. Several major technical challenges had to be addressed during development of Kokkos' Task DAG capability: (1) portability to a GPU with it's simplified hardware and micro- runtime, (2) thread-scalable memory allocation and deallocation from a bounded pool of memory, (3) thread-scalable scheduler for dynamic task DAG, (4) usability by applications.

  14. Campus Capability Plan

    Energy Technology Data Exchange (ETDEWEB)

    Adams, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Arsenlis, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bailey, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bergman, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brase, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brenner, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Camara, L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Carlton, H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Cheng, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Chrzanowski, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Colson, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); East, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Farrell, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ferranti, L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gursahani, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hansen, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Helms, L. L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hernandez, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Jeffries, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Larson, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Lu, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McNabb, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mercer, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Skeate, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sueksdorf, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zucca, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Le, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ancria, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Scott, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Leininger, L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gagliardi, F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gash, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bronson, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Chung, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hobson, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Meeker, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sanchez, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zagar, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Quivey, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sommer, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Atherton, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-06-06

    Lawrence Livermore National Laboratory Campus Capability Plan for 2018-2028. Lawrence Livermore National Laboratory (LLNL) is one of three national laboratories that are part of the National Nuclear Security Administration. LLNL provides critical expertise to strengthen U.S. security through development and application of world-class science and technology that: Ensures the safety, reliability, and performance of the U.S. nuclear weapons stockpile; Promotes international nuclear safety and nonproliferation; Reduces global danger from weapons of mass destruction; Supports U.S. leadership in science and technology. Essential to the execution and continued advancement of these mission areas are responsive infrastructure capabilities. This report showcases each LLNL capability area and describes the mission, science, and technology efforts enabled by LLNL infrastructure, as well as future infrastructure plans.

  15. Power index method for operational capability evaluation of weapon equipment based on ANP and simulation%基于ANP和仿真的武器装备作战能力幂指数评估方法

    Institute of Scientific and Technical Information of China (English)

    石福丽; 杨峰; 许永平; 吴国栋

    2011-01-01

    针对武器装备作战能力幂指数评估模型中评估指标之间存在相互依赖或影响关系,以及评估过程主观性较强的情况,提出了基于ANP和仿真的武器装备作战能力幂指数评估框架.研究了该框架中涉及的两项关键技术,即网络化评估指标体系设计与优化方法及基于专家和仿真数据的ANP超矩阵构建方法.以潜艇反舰作战能力评估为例,构建了相应的网络化评估指标体系,得到了基于ANP和仿真的潜艇反舰作战能力幂指数评估模型,并将评估结果与传统的基于AHP方法的幂指数评估模型的结果比较分析,验证了方法的合理性和有效性.%In order to cope with the interdependence and interrelationship between evaluation metrica in conventional power index model, and eliminate the subjectivity of expert's preference in the evaluation process, this paper proposes a framework that aupports to create power index model for operational capability evaluation of weapon equipments based on the analytic network process (ANP) and simulation experiment. Then it discusses two essential techniques, the method to design and optimize of networked evaluation index system and the approach to construct ANP supermatrix based on expert's knowledge and simulation, of the proposed framework in detail. Finally, taking an anti-ship operations scenario of submarine as example, it builds corresponding networked index system and ANP based evaluation model with applying above-mentioned methods, and verifies the reasonability and effectiveness of proposed framework and techniques by comparing and analyzing the simulation results.

  16. Management Innovation Capabilities

    DEFF Research Database (Denmark)

    Harder, Mie

    Management innovation is the implementation of a new management practice, process, technique or structure that significantly alters the way the work of management is performed. This paper presents a typology categorizing management innovation along two dimensions; radicalness and complexity. Then......, the paper introduces the concept of management innovation capabilities which refers to the ability of a firm to purposefully create, extend and modify its managerial resource base to address rapidly changing environments. Drawing upon behavioral theory of the firm and the dynamic capabilities framework......, the paper proposes a model of the foundations of management innovation. Propositions and implications for future research are discussed....

  17. Sandia QIS Capabilities.

    Energy Technology Data Exchange (ETDEWEB)

    Muller, Richard P. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-07-01

    Sandia National Laboratories has developed a broad set of capabilities in quantum information science (QIS), including elements of quantum computing, quantum communications, and quantum sensing. The Sandia QIS program is built atop unique DOE investments at the laboratories, including the MESA microelectronics fabrication facility, the Center for Integrated Nanotechnologies (CINT) facilities (joint with LANL), the Ion Beam Laboratory, and ASC High Performance Computing (HPC) facilities. Sandia has invested $75 M of LDRD funding over 12 years to develop unique, differentiating capabilities that leverage these DOE infrastructure investments.

  18. Capability Handbook- offline metrology

    DEFF Research Database (Denmark)

    Islam, Aminul; Marhöfer, David Maximilian; Tosello, Guido

    This offline metrological capability handbook has been made in relation to HiMicro Task 3.3. The purpose of this document is to assess the metrological capability of the HiMicro partners and to gather the information of all available metrological instruments in the one single document. It provides...... a quick overview of what is possible today by the state of the art, what the HiMicro consortium can do and what metrological requirements we have concerning the HiMicro industrial demonstrators....

  19. Coupling Magnetic Fields and ALE Hydrodynamics for 3D Simulations of MFCG's

    Energy Technology Data Exchange (ETDEWEB)

    White, D; Rieben, R; Wallin, B

    2006-09-20

    We review the development of a full 3D multiphysics code for the simulation of explosively driven Magnetic Flux Compression Generators (MFCG) and related pulse power devices. In a typical MFCG the device is seeded with an initial electric current and the device is then detonated. The detonation compresses the magnetic field and amplifies the current. This is a multiphysics problem in that detonation kinetics, electromagnetic diffusion and induction, material deformation, and thermal effects are all important. This is a tightly coupled problem in that the different physical quantities have comparable spatial and temporal variation, and hence should be solved simultaneously on the same computational mesh.

  20. A Multi-Code Analysis Toolkit for Astrophysical Simulation Data

    OpenAIRE

    Turk, Matthew J.; Smith., Britton D.; Oishi, Jeffrey S.; Skory, Stephen; Skillman, Samuel W.; Abel, Tom; Norman, Michael L.

    2010-01-01

    The analysis of complex multiphysics astrophysical simulations presents a unique and rapidly growing set of challenges: reproducibility, parallelization, and vast increases in data size and complexity chief among them. In order to meet these challenges, and in order to open up new avenues for collaboration between users of multiple simulation platforms, we present yt (available at http://yt.enzotools.org/), an open source, community-developed astrophysical analysis and visualization toolkit. ...

  1. Algorithms for Model Calibration of Ground Water Simulators

    Science.gov (United States)

    2014-11-20

    cobian, and Jacobian-vector products are computed with a Monte Carlo simulation. This situation differs from the textbook case [5] in that one does not...Anderson acceleration is a natural method for multi-physics coupling (for example subsurface flow, chemistry , and heat transfer) when the individual physics...Online publication 7/12/2014. [11] J. Nance and C. T. Kelley, A sparse interpolation algorithm for dynamical simulations in compu- tational chemistry

  2. Capabilities Composition (Briefing Charts)

    Science.gov (United States)

    2009-04-22

    and support , , processes (including ITIL v3) • Understanding of Governance is still evolving Engineering Acquisition and Operational Governance...L – Logistics • NC – Net-Centric • CPM – Capability Portfolio Management • ITIL v3 – Information Technology • ONR – Office of Naval Research

  3. Building server capabilities

    DEFF Research Database (Denmark)

    Adeyemi, Oluseyi

    -only”, exporting parts and components back to headquarter for sales in the home country. In the course of time, the role of offshore subsidiaries in a company’s operations network tends to change and, with that, the capabilities, of the subsidiaries. Focusing on Danish subsidiaries in China, the objective...

  4. Building Server Capabilities

    DEFF Research Database (Denmark)

    Adeyemi, Oluseyi

    2013-01-01

    -only”, exporting parts and components back to headquarter for sales in the home country. In the course of time, the role of offshore subsidiaries in a company’s operations network tends to change and, with that, the capabilities, of the subsidiaries. Focusing on Danish subsidiaries in China, the objective...

  5. Capabilities Report 2012

    Science.gov (United States)

    2012-01-01

    74 Biosurveillance - Rapid Identification of Unknown Microorganisms...RSI is dedicated to the effort and capabilities of enabling biosurveillance through coordinated and integrated national and international systems...natural, accidental, or deliberate in nature. These initiatives include: biosurveillance , outbreak recognition and avoidance, pathogen characterization

  6. Capabilities for Intercultural Dialogue

    Science.gov (United States)

    Crosbie, Veronica

    2014-01-01

    The capabilities approach offers a valuable analytical lens for exploring the challenge and complexity of intercultural dialogue in contemporary settings. The central tenets of the approach, developed by Amartya Sen and Martha Nussbaum, involve a set of humanistic goals including the recognition that development is a process whereby people's…

  7. Metrology Measurement Capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Glen E. Gronniger

    2007-10-02

    This document contains descriptions of Federal Manufacturing & Technologies (FM&T) Metrology capabilities, traceability flow charts, and the measurement uncertainty of each measurement capability. Metrology provides NIST traceable precision measurements or equipment calibration for a wide variety of parameters, ranges, and state-of-the-art uncertainties. Metrology laboratories conform to the requirements of the Department of Energy Development and Production Manual Chapter 13.2, ANSI/ISO/IEC ANSI/ISO/IEC 17025:2005, and ANSI/NCSL Z540-1. FM&T Metrology laboratories are accredited by NVLAP for the parameters, ranges, and uncertainties listed in the specific scope of accreditation under NVLAP Lab code 200108-0. See the Internet at http://ts.nist.gov/Standards/scopes/2001080.pdf. These parameters are summarized. The Honeywell Federal Manufacturing & Technologies (FM&T) Metrology Department has developed measurement technology and calibration capability in four major fields of measurement: (1) Mechanical; (2) Environmental, Gas, Liquid; (3) Electrical (DC, AC, RF/Microwave); and (4) Optical and Radiation. Metrology Engineering provides the expertise to develop measurement capabilities for virtually any type of measurement in the fields listed above. A strong audit function has been developed to provide a means to evaluate the calibration programs of our suppliers and internal calibration organizations. Evaluation includes measurement audits and technical surveys.

  8. ISOPHOT - Capabilities and performance

    DEFF Research Database (Denmark)

    Lemke, D.; Klaas, U.; Abolins, J.

    1996-01-01

    ISOPHOT covers the largest wavelength range on ISO from 2.5 to 240 mu m. Its scientific capabilities include multi filter and multi-aperture photometry, polarimetry, imaging and spectrophotometry. All modes can optionally include a focal plane chopper. The backbone of the photometric calibration...

  9. Capabilities for Intercultural Dialogue

    Science.gov (United States)

    Crosbie, Veronica

    2014-01-01

    The capabilities approach offers a valuable analytical lens for exploring the challenge and complexity of intercultural dialogue in contemporary settings. The central tenets of the approach, developed by Amartya Sen and Martha Nussbaum, involve a set of humanistic goals including the recognition that development is a process whereby people's…

  10. The Capability Approach

    NARCIS (Netherlands)

    I.A.M. Robeyns (Ingrid)

    2011-01-01

    textabstract In its most general description, the capability approach is a flexible and multi-purpose normative framework, rather than a precise theory of well-being, freedom or justice. At its core are two normative claims: first, the claim that the freedom to achieve well-being is of primary mora

  11. Simulation

    DEFF Research Database (Denmark)

    Gould, Derek A; Chalmers, Nicholas; Johnson, Sheena J

    2012-01-01

    Recognition of the many limitations of traditional apprenticeship training is driving new approaches to learning medical procedural skills. Among simulation technologies and methods available today, computer-based systems are topical and bring the benefits of automated, repeatable, and reliable p...... performance assessments. Human factors research is central to simulator model development that is relevant to real-world imaging-guided interventional tasks and to the credentialing programs in which it would be used.......Recognition of the many limitations of traditional apprenticeship training is driving new approaches to learning medical procedural skills. Among simulation technologies and methods available today, computer-based systems are topical and bring the benefits of automated, repeatable, and reliable...

  12. Capitalizing on capabilities.

    Science.gov (United States)

    Ulrich, Dave; Smallwood, Norm

    2004-06-01

    By making the most of organizational capabilities--employees' collective skills and fields of expertise--you can dramatically improve your company's market value. Although there is no magic list of proficiencies that every organization needs in order to succeed, the authors identify 11 intangible assets that well-managed companies tend to have: talent, speed, shared mind-set and coherent brand identity, accountability, collaboration, learning, leadership, customer connectivity, strategic unity, innovation, and efficiency. Such companies typically excel in only three of these capabilities while maintaining industry parity in the other areas. Organizations that fall below the norm in any of the 11 are likely candidates for dysfunction and competitive disadvantage. So you can determine how your company fares in these categories (or others, if the generic list doesn't suit your needs), the authors explain how to conduct a "capabilities audit," describing in particular the experiences and findings of two companies that recently performed such audits. In addition to highlighting which intangible assets are most important given the organization's history and strategy, this exercise will gauge how well your company delivers on its capabilities and will guide you in developing an action plan for improvement. A capabilities audit can work for an entire organization, a business unit, or a region--indeed, for any part of a company that has a strategy to generate financial or customer-related results. It enables executives to assess overall company strengths and weaknesses, senior leaders to define strategy, midlevel managers to execute strategy, and frontline leaders to achieve tactical results. In short, it helps turn intangible assets into concrete strengths.

  13. Simulation

    CERN Document Server

    Ross, Sheldon

    2006-01-01

    Ross's Simulation, Fourth Edition introduces aspiring and practicing actuaries, engineers, computer scientists and others to the practical aspects of constructing computerized simulation studies to analyze and interpret real phenomena. Readers learn to apply results of these analyses to problems in a wide variety of fields to obtain effective, accurate solutions and make predictions about future outcomes. This text explains how a computer can be used to generate random numbers, and how to use these random numbers to generate the behavior of a stochastic model over time. It presents the statist

  14. The New MCNP6 Depletion Capability

    Energy Technology Data Exchange (ETDEWEB)

    Fensin, Michael Lorne [Los Alamos National Laboratory; James, Michael R. [Los Alamos National Laboratory; Hendricks, John S. [Los Alamos National Laboratory; Goorley, John T. [Los Alamos National Laboratory

    2012-06-19

    The first MCNP based inline Monte Carlo depletion capability was officially released from the Radiation Safety Information and Computational Center as MCNPX 2.6.0. Both the MCNP5 and MCNPX codes have historically provided a successful combinatorial geometry based, continuous energy, Monte Carlo radiation transport solution for advanced reactor modeling and simulation. However, due to separate development pathways, useful simulation capabilities were dispersed between both codes and not unified in a single technology. MCNP6, the next evolution in the MCNP suite of codes, now combines the capability of both simulation tools, as well as providing new advanced technology, in a single radiation transport code. We describe here the new capabilities of the MCNP6 depletion code dating from the official RSICC release MCNPX 2.6.0, reported previously, to the now current state of MCNP6. NEA/OECD benchmark results are also reported. The MCNP6 depletion capability enhancements beyond MCNPX 2.6.0 reported here include: (1) new performance enhancing parallel architecture that implements both shared and distributed memory constructs; (2) enhanced memory management that maximizes calculation fidelity; and (3) improved burnup physics for better nuclide prediction. MCNP6 depletion enables complete, relatively easy-to-use depletion calculations in a single Monte Carlo code. The enhancements described here help provide a powerful capability as well as dictate a path forward for future development to improve the usefulness of the technology.

  15. Multiphysics Thermal-Fluid Design Analysis of a Non-Nuclear Tester for Hot-Hydrogen Materials and Component Development

    Science.gov (United States)

    Wang, Ten-See; Foote, John; Litchford, Ron

    2006-01-01

    The objective of this effort is to perform design analyses for a non-nuclear hot-hydrogen materials tester, as a first step towards developing efficient and accurate multiphysics, thermo-fluid computational methodology to predict environments for hypothetical solid-core, nuclear thermal engine thrust chamber design and analysis. The computational methodology is based on a multidimensional, finite-volume, turbulent, chemically reacting, thermally radiating, unstructured-grid, and pressure-based formulation. The multiphysics invoked in this study include hydrogen dissociation kinetics and thermodynamics, turbulent flow, convective, and thermal radiative heat transfers. The goals of the design analyses are to maintain maximum hot-hydrogen jet impingement energy and to minimize chamber wall heating. The results of analyses on three test fixture configurations and the rationale for final selection are presented. The interrogation of physics revealed that reactions of hydrogen dissociation and recombination are highly correlated with local temperature and are necessary for accurate prediction of the hot-hydrogen jet temperature.

  16. Capturing the complex behavior of hydraulic fracture stimulation through multi-physics modeling, field-based constraints, and model reduction

    Science.gov (United States)

    Johnson, S.; Chiaramonte, L.; Cruz, L.; Izadi, G.

    2016-12-01

    Advances in the accuracy and fidelity of numerical methods have significantly improved our understanding of coupled processes in unconventional reservoirs. However, such multi-physics models are typically characterized by many parameters and require exceptional computational resources to evaluate systems of practical importance, making these models difficult to use for field analyses or uncertainty quantification. One approach to remove these limitations is through targeted complexity reduction and field data constrained parameterization. For the latter, a variety of field data streams may be available to engineers and asset teams, including micro-seismicity from proximate sites, well logs, and 3D surveys, which can constrain possible states of the reservoir as well as the distributions of parameters. We describe one such workflow, using the Argos multi-physics code and requisite geomechanical analysis to parameterize the underlying models. We illustrate with a field study involving a constraint analysis of various field data and details of the numerical optimizations and model reduction to demonstrate how complex models can be applied to operation design in hydraulic fracturing operations, including selection of controllable completion and fluid injection design properties. The implication of this work is that numerical methods are mature and computationally tractable enough to enable complex engineering analysis and deterministic field estimates and to advance research into stochastic analyses for uncertainty quantification and value of information applications.

  17. Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC) verification and validation plan. version 1.

    Energy Technology Data Exchange (ETDEWEB)

    Bartlett, Roscoe Ainsworth; Arguello, Jose Guadalupe, Jr.; Urbina, Angel; Bouchard, Julie F.; Edwards, Harold Carter; Freeze, Geoffrey A.; Knupp, Patrick Michael; Wang, Yifeng; Schultz, Peter Andrew; Howard, Robert (Oak Ridge National Laboratory, Oak Ridge, TN); McCornack, Marjorie Turner

    2011-01-01

    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. To meet this objective, NEAMS Waste IPSC M&S capabilities will be applied to challenging spatial domains, temporal domains, multiphysics couplings, and multiscale couplings. A strategic verification and validation (V&V) goal is to establish evidence-based metrics for the level of confidence in M&S codes and capabilities. Because it is economically impractical to apply the maximum V&V rigor to each and every M&S capability, M&S capabilities will be ranked for their impact on the performance assessments of various components of the repository systems. Those M&S capabilities with greater impact will require a greater level of confidence and a correspondingly greater investment in V&V. This report includes five major components: (1) a background summary of the NEAMS Waste IPSC to emphasize M&S challenges; (2) the conceptual foundation for verification, validation, and confidence assessment of NEAMS Waste IPSC M&S capabilities; (3) specifications for the planned verification, validation, and confidence-assessment practices; (4) specifications for the planned evidence information management system; and (5) a path forward for the incremental implementation of this V&V plan.

  18. High-resolution 3D simulations of NIF ignition targets performed on Sequoia with HYDRA

    Science.gov (United States)

    Marinak, M. M.; Clark, D. S.; Jones, O. S.; Kerbel, G. D.; Sepke, S.; Patel, M. V.; Koning, J. M.; Schroeder, C. R.

    2015-11-01

    Developments in the multiphysics ICF code HYDRA enable it to perform large-scale simulations on the Sequoia machine at LLNL. With an aggregate computing power of 20 Petaflops, Sequoia offers an unprecedented capability to resolve the physical processes in NIF ignition targets for a more complete, consistent treatment of the sources of asymmetry. We describe modifications to HYDRA that enable it to scale to over one million processes on Sequoia. These include new options for replicating parts of the mesh over a subset of the processes, to avoid strong scaling limits. We consider results from a 3D full ignition capsule-only simulation performed using over one billion zones run on 262,000 processors which resolves surface perturbations through modes l = 200. We also report progress towards a high-resolution 3D integrated hohlraum simulation performed using 262,000 processors which resolves surface perturbations on the ignition capsule through modes l = 70. These aim for the most complete calculations yet of the interactions and overall impact of the various sources of asymmetry for NIF ignition targets. This work was performed under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under Contract No. DE-AC52-07NA27344.

  19. Design and simulation of superconducting Lorentz Force Electrical Impedance Tomography (LFEIT)

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Boyang, E-mail: bs506@cam.ac.uk; Fu, Lin, E-mail: lf359@cam.ac.uk; Geng, Jianzhao, E-mail: jg717@cam.ac.uk; Zhang, Xiuchang, E-mail: xz326@cam.ac.uk; Zhang, Heng, E-mail: hz301@cam.ac.uk; Dong, Qihuan, E-mail: qd210@cam.ac.uk; Li, Chao, E-mail: cl644@cam.ac.uk; Li, Jing, E-mail: jl908@cam.ac.uk; Coombs, T.A., E-mail: tac1000@cam.ac.uk

    2016-05-15

    Highlights: • Design of superconducting magnets using Halbach Array configuration. • Combination of superconducting magnets together with Lorentz Force Electrical Impedance Tomography (LFEIT) system. • Simulation of superconducting LFEIT system based on the theory of magneto-acoustic effect. - Abstract: Lorentz Force Electrical Impedance Tomography (LFEIT) is a hybrid diagnostic scanner with strong capability for biological imaging, particularly in cancer and haemorrhages detection. This paper presents the design and simulation of a novel combination: a superconducting magnet together with LFEIT system. Superconducting magnets can generate magnetic field with high intensity and homogeneity, which could significantly enhance the imaging performance. The modelling of superconducting magnets was carried out using Finite Element Method (FEM) package, COMSOL Multiphysics, which was based on Partial Differential Equation (PDE) model with H-formulation coupling B-dependent critical current density and bulk approximation. The mathematical model for LFEIT system was built based on the theory of magneto-acoustic effect. The magnetic field properties from magnet design were imported into the LFEIT model. The basic imaging of electrical signal was developed using MATLAB codes. The LFEIT model simulated two samples located in three different magnetic fields with varying magnetic strength and homogeneity.

  20. Superheating and melting within aluminum core-oxide shell nanoparticles for a broad range of heating rates: multiphysics phase field modeling.

    Science.gov (United States)

    Hwang, Yong Seok; Levitas, Valery I

    2016-10-19

    The external surface of metallic particles is usually covered by a thin and strong oxide shell, which significantly affects superheating and melting of particles. The effects of geometric parameters and heating rate on characteristic melting and superheating temperatures and melting behavior of aluminum nanoparticles covered by an oxide shell were studied numerically. For this purpose, the multiphysics model that includes the phase field model for surface melting, a dynamic equation of motion, a mechanical model for stress and strain simulations, interface and surface stresses, and the thermal conduction model including thermoelastic and thermo-phase transformation coupling as well as transformation dissipation rate was formulated. Several nontrivial phenomena were revealed. In comparison with a bare particle, the pressure generated in a core due to different thermal expansions of the core and shell and transformation volumetric expansion during melting, increases melting temperatures with the Clausius-Clapeyron factor of 60 K GPa(-1). For the heating rates Q ≤ 10(9) K s(-1), melting temperatures (surface and bulk start and finish melting temperatures, and maximum superheating temperature) are independent of Q. For Q ≥ 10(12) K s(-1), increasing Q generally increases melting temperatures and temperature for the shell fracture. Unconventional effects start for Q ≥ 10(12) K s(-1) due to kinetic superheating combined with heterogeneous melting and geometry. The obtained results are applied to shed light on the initial stage of the melt-dispersion-mechanism of the reaction of Al nanoparticles. Various physical phenomena that promote or suppress melting and affect melting temperatures and temperature of the shell fracture for different heating-rate ranges are summarized in the corresponding schemes.

  1. Multi-initial-conditions and Multi-physics Ensembles in the Weather Research and Forecasting Model to Improve Coastal Stratocumulus Forecasts for Solar Power Integration

    Science.gov (United States)

    Yang, H.

    2015-12-01

    In coastal Southern California, variation in solar energy production is predominantly due to the presence of stratocumulus clouds (Sc), as they greatly attenuate surface solar irradiance and cover most distributed photovoltaic systems on summer mornings. Correct prediction of the spatial coverage and lifetime of coastal Sc is therefore vital to the accuracy of solar energy forecasts in California. In Weather Research and Forecasting (WRF) model simulations, underprediction of Sc inherent in the initial conditions directly leads to an underprediction of Sc in the resulting forecasts. Hence, preprocessing methods were developed to create initial conditions more consistent with observational data and reduce spin-up time requirements. Mathiesen et al. (2014) previously developed a cloud data assimilation system to force WRF initial conditions to contain cloud liquid water based on CIMSS GOES Sounder cloud cover. The Well-mixed Preprocessor and Cloud Data Assimilation (WEMPPDA) package merges an initial guess of cloud liquid water content obtained from mixed-layer theory with assimilated CIMSS GOES Sounder cloud cover to more accurately represent the spatial coverage of Sc at initialization. The extent of Sc inland penetration is often constrained topographically; therefore, the low inversion base height (IBH) bias in NAM initial conditions decreases Sc inland penetration. The Inversion Base Height (IBH) package perturbs the initial IBH by the difference between model IBH and the 12Z radiosonde measurement. The performance of these multi-initial-condition configurations was evaluated over June, 2013 against SolarAnywhere satellite-derived surface irradiance data. Four configurations were run: 1) NAM initial conditions, 2) RAP initial conditions, 3) WEMPPDA applied to NAM, and 4) IBH applied to NAM. Both preprocessing methods showed significant improvement in the prediction of both spatial coverage and lifetime of coastal Sc. The best performing configuration was then

  2. Numerical simulations of coupled problems in engineering

    CERN Document Server

    2014-01-01

    This book presents and discusses mathematical models, numerical methods and computational techniques used for solving coupled problems in science and engineering. It takes a step forward in the formulation and solution of real-life problems with a multidisciplinary vision, accounting for all of the complex couplings involved in the physical description. Simulation of multifaceted physics problems is a common task in applied research and industry. Often a suitable solver is built by connecting together several single-aspect solvers into a network. In this book, research in various fields was selected for consideration: adaptive methodology for multi-physics solvers, multi-physics phenomena and coupled-field solutions, leading to computationally intensive structural analysis. The strategies which are used to keep these problems computationally affordable are of special interest, and make this an essential book.

  3. Metrology Measurement Capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, L.M.

    2000-03-23

    This document contains descriptions of Federal Manufacturing and Technologies (FM and T) Metrology capabilities, traceability flow charts, and the measurement uncertainty of each measurement capability. Metrology provides NIST traceable precision measurements or equipment calibration for a wide variety of parameters, ranges, and state-of-the-art uncertainties in laboratories that conform to the requirements of the Department of Energy Development and Production Manual Chapter 8.4, and ANSI/NCSL Z540-1 (equivalent to ISO Guide 25). FM and T Metrology laboratories are accredited by NVLAP for the parameters, ranges, and uncertainties listed in the specific scope of accreditation under NVLAP Lab code 200108-0. These parameters are summarized.

  4. Metrology Measurement Capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, L.M.

    2003-11-12

    This document contains descriptions of Federal Manufacturing & Technologies (FM&T) Metrology capabilities, traceability flow charts, and the measurement uncertainty of each measurement capability. Metrology provides NIST traceable precision measurements or equipment calibration for a wide variety of parameters, ranges, and state-of-the-art uncertainties. Metrology laboratories conform to the requirements of the Department of Energy Development and Production Manual Chapter 8.4, ANSI/ISO/IEC ANSI/ISO/IEC 17025:2000, and ANSI/NCSL Z540-1 (equivalent to ISO Guide 25). FM&T Metrology laboratories are accredited by NVLAP for the parameters, ranges, and uncertainties listed in the specific scope of accreditation under NVLAP Lab code 200108-0. See the Internet at http://ts.nist.gov/ts/htdocs/210/214/scopes/2001080.pdf. These parameters are summarized in the table at the bottom of this introduction.

  5. Capabilities and Special Needs

    DEFF Research Database (Denmark)

    Kjeldsen, Christian Christrup

    thesis deals with a new Danish innovative policy (Act. no. 564 of 2007), a social work and educational intervention for mentally challenged Young people and other young people with special needs, the so-called individually arranged youth education (STU). The investigated area has lately been taken......The author, Christian Christrup Kjeldsen, presents a comprehensive capability-oriented study of high excellence. For this work he has recieved the doctor titel Dr.phil (Doktor der Philosophie) from Bielefeld University, Germany 2013 with the highest possible grade "ausgezeichnet". The doctoral...... into international consideration in relation to the implementation of the UN convention on the rights of persons with disabilities. As for the theoretical basis, the research makes use of the sociological open-ended and relational concepts of Pierre Bourdieu and the normative yardstick of the Capability Approach...

  6. Capabilities and Special Needs

    DEFF Research Database (Denmark)

    Kjeldsen, Christian Christrup

    The author, Christian Christrup Kjeldsen, presents a comprehensive capability-oriented study of high excellence. For this work he has recieved the doctor titel Dr.phil (Doktor der Philosophie) from Bielefeld University, Germany 2013 with the highest possible grade "ausgezeichnet". The doctoral...... thesis deals with a new Danish innovative policy (Act. no. 564 of 2007), a social work and educational intervention for mentally challenged Young people and other young people with special needs, the so-called individually arranged youth education (STU). The investigated area has lately been taken...... into international consideration in relation to the implementation of the UN convention on the rights of persons with disabilities. As for the theoretical basis, the research makes use of the sociological open-ended and relational concepts of Pierre Bourdieu and the normative yardstick of the Capability Approach...

  7. Joint Forces Capabilities

    Science.gov (United States)

    2007-11-02

    for countering the proliferation of weapons of mass destruction (WMD) in space. The Space Operations Center ( SPOC ), USSPACECOM is the single point...of contact for assessing space capabilities. Combatant commanders, subordinate JFCs, and Services can access this information from the SPOC via the...special operations forces SPOC Space Operations Center SSBN fleet ballistic missile submarine SST space support team UJTL Universal Joint Task List UN

  8. Capabilities for innovation

    DEFF Research Database (Denmark)

    Nielsen, Peter; Nielsen, René Nesgaard; Bamberger, Simon Grandjean

    2012-01-01

    is a survey that collected information from 601 firms belonging to the private urban sector in Denmark. The survey was carried out in late 2010. Keywords: dynamic capabilities/innovation/globalization/employee/employer cooperation/Nordic model Acknowledgment: The GOPA study was financed by grant 20080053113....../12-2008-09 from the Foundation for Research of Work Environment, Denmark. The funders played no part in the conduct or reporting of the research....

  9. Model biases in high-burnup fast reactor simulations

    Energy Technology Data Exchange (ETDEWEB)

    Touran, N.; Cheatham, J.; Petroski, R. [TerraPower LLC, 11235 S.E. 6th St, Bellevue, WA 98004 (United States)

    2012-07-01

    A new code system called the Advanced Reactor Modeling Interface (ARMI) has been developed that loosely couples multiscale, multiphysics nuclear reactor simulations to provide rapid, user-friendly, high-fidelity full systems analysis. Incorporating neutronic, thermal-hydraulic, safety/transient, fuel performance, core mechanical, and economic analyses, ARMI provides 'one-click' assessments of many multi-disciplined performance metrics and constraints that historically require iterations between many diverse experts. The capabilities of ARMI are implemented in this study to quantify neutronic biases of various modeling approximations typically made in fast reactor analysis at an equilibrium condition, after many repetitive shuffles. Sensitivities at equilibrium that result in very high discharge burnup are considered ( and >20% FIMA), as motivated by the development of the Traveling Wave Reactor. Model approximations discussed include homogenization, neutronic and depletion mesh resolution, thermal-hydraulic coupling, explicit control rod insertion, burnup-dependent cross sections, fission product model, burn chain truncation, and dynamic fuel performance. The sensitivities of these approximations on equilibrium discharge burnup, k{sub eff}, power density, delayed neutron fraction, and coolant temperature coefficient are discussed. (authors)

  10. Community Petascale Project for Accelerator Science and Simulation: Advancing Computational Science for Future Accelerators and Accelerator Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Spentzouris, P.; /Fermilab; Cary, J.; /Tech-X, Boulder; McInnes, L.C.; /Argonne; Mori, W.; /UCLA; Ng, C.; /SLAC; Ng, E.; Ryne, R.; /LBL, Berkeley

    2011-11-14

    The design and performance optimization of particle accelerators are essential for the success of the DOE scientific program in the next decade. Particle accelerators are very complex systems whose accurate description involves a large number of degrees of freedom and requires the inclusion of many physics processes. Building on the success of the SciDAC-1 Accelerator Science and Technology project, the SciDAC-2 Community Petascale Project for Accelerator Science and Simulation (ComPASS) is developing a comprehensive set of interoperable components for beam dynamics, electromagnetics, electron cooling, and laser/plasma acceleration modelling. ComPASS is providing accelerator scientists the tools required to enable the necessary accelerator simulation paradigm shift from high-fidelity single physics process modeling (covered under SciDAC1) to high-fidelity multiphysics modeling. Our computational frameworks have been used to model the behavior of a large number of accelerators and accelerator R&D experiments, assisting both their design and performance optimization. As parallel computational applications, the ComPASS codes have been shown to make effective use of thousands of processors. ComPASS is in the first year of executing its plan to develop the next-generation HPC accelerator modeling tools. ComPASS aims to develop an integrated simulation environment that will utilize existing and new accelerator physics modules with petascale capabilities, by employing modern computing and solver technologies. The ComPASS vision is to deliver to accelerator scientists a virtual accelerator and virtual prototyping modeling environment, with the necessary multiphysics, multiscale capabilities. The plan for this development includes delivering accelerator modeling applications appropriate for each stage of the ComPASS software evolution. Such applications are already being used to address challenging problems in accelerator design and optimization. The ComPASS organization

  11. Multiphysics Modeling and Simulations of Mil A46100 Armor-Grade Martensitic Steel Gas Metal Arc Welding Process

    Science.gov (United States)

    2013-05-23

    Technology Laboratory, Watertown, MA, 1992 2. J.G. Holmes and B.J. Resnick, Flexible Robot Arc Welding System, Soc. Manuf. Eng., 1979, MS (79) 3. U.S...Process, Proceedings of the IEEE International Conference on Robotics and Automation, Detroit, Vol. 4, p 3059–3064 19. Z. Bingul and G.E. Cook, A Real-Time...Prediction Model of Electrode Extension for GMAW, IEEE/ASME Trans. Mechatron ., 2006, 11, p 47–54 20. T.P. Quinn, R.B. Madigan, and T.A. Siewert, An

  12. Finite element simulation of the healthy and degenerated lumbar spine : interplay between muscle activity and intervertebral disc multiphysics

    OpenAIRE

    Toumanidou, Themis

    2016-01-01

    The human spine provides mechanical support to the trunk while it protects the spinal cord and nerves from the external loads transferred during daily activities. Such loads are largely controlled by the spine muscles and influence the biophysical regulation of the intervertebral discs (IVD). Numerical models have been important tools for the translation of the external forces into internal loads that otherwise cannot be easily measured directly. This PhD thesis used the predictive ability of...

  13. USE OF AUTODESK SIMULATION MULTIPHYSICS FOR RESEARCH OF TEMPERATURE FIELDS, STRESS AND DEFOMATION IN THE CONSTRUCTION OF GEAR PUMP

    Directory of Open Access Journals (Sweden)

    A. V. Puzanov

    2016-01-01

    Full Text Available Gear pumps are the most common type of hydraulic machines. They are used in various industries: oil and gas processing industry, in machine tools, mobile military, road-building and agricultural machinery. The need to ensure efficiency of hydraulic mobile applications in a wide climatic range requires increasing the accuracy of the calculation methods for the design of their elements. The results of temperature field modeling and caused them stress and strain. The results obtained allowed to justify the design and technological solutions, providing an increase of hydraulic performance at critical ambient temperatures.

  14. Advanced Simulation Center

    Data.gov (United States)

    Federal Laboratory Consortium — The Advanced Simulation Center consists of 10 individual facilities which provide missile and submunition hardware-in-the-loop simulation capabilities. The following...

  15. 非对称行星探测车行走系统的动力学仿真及运动性能分析%Dynamics Simulation and Motion Capability Analysis on the Mobile System for Asymmetric Planetary Rover

    Institute of Scientific and Technical Information of China (English)

    杜建军; 任明俊; 刘暾; 朱建军

    2011-01-01

    为了提高探测车在崎岖路面中的运动性能,提出了一种非对称轮式探测车行走系统.该车具有整体式超静定结构,6个车轮通过悬挂装置与车身相连,非对称分布于车体两侧,悬架结构可以主动控制来提高探测车在崎岖路面中的运动性能.采用牛顿-欧拉法建立了行走系统的动力学模型,给出了几何和速度约束方程,采用有限差分法求解由微分方程和代数方程构成的联合方程组.对非对称构型探测车的运动性能进行了计算机仿真,得出了一些运动规律.原理样机试验表明,该车具有较强的越障和过沟能力.%A kind of asymmetric mobile system for wheeled royers is proposed for enhancing motion performance in rough terrain. The rover has an integral and statically indeterminate structure with six wheels asymmetrically joined at the two sides by suspension mechanism. The suspension configuration can be actively controlled to improve the rover mobility in high challenging terrains. Newton-Euler method is adopted to establish dynamic model for the mobile system, and the geometry and velocity constraint equations are given. The equation system consisting of differential and algebraic equations is solved by finite difference method. Simulations are performed to study the dynamic performance of the asymmetric rover,and some motion laws are obtained. The strong obstacle-overcoming and ditch-passing capabilities of the rover are testified by experiments on the principle prototype.

  16. Adsorption Capability of Ultrafine Fly Ash to Malachite Green in Simulated Wastewater%超细粉煤灰对模拟废水中孔雀石绿的吸附性能

    Institute of Scientific and Technical Information of China (English)

    李北罡; 乔丽萍

    2012-01-01

    The ultrafine fly ash (UFA) prepared by ball-milling was used as adsorption material, and its adsorption capability to malachite green (MG) in the simulated wastewater was studied by shaking adsorption method. The experimental results show that; Under the conditions of UFA dosage 10 g/Lt adsorption temperature 298 K, initial MG mass concentration 500 mg/L, shaking time 120 min and natural pH of wastewater, the equilibrium adsorption capacity can reach 49.97 mg/g and almost all MG is adsorbed on UFA; The adsorption process of MG on UFA fits well with the second-order adsorption kinetic equation with 3.95 kJ/mol of Ea; The adsorption rate is fast and controlled by intra-particle diffusion of MG in UFA; The adsorption process accords with Langmuir isotherm equation, and the saturated adsorption capacity decreases with the increasing of adsorption temperature and can reach 526.32 mg/g at 298 K; The adsorption process is a spontaneous and exothermic reaction process.%以球磨制得的超细粉煤灰为吸附材料,采用振荡吸附法研究了其对模拟废水中孔雀石绿的吸附性能.实验结果表明:在超细粉煤灰加入量为10g/L、吸附温度为298K、初始孔雀石绿质量浓度为500mg/L、振荡时间为120min、孔雀石绿废水自然酸碱度条件下,达到吸附平衡时的吸附量为49.97 mg/g,孔雀石绿几乎全部被超细粉煤灰所吸附;该吸附反应很好地符合二级吸附动力学方程,Ea为3.95kJ/mol,吸附反应速率较快,吸附过程由孔雀石绿在超细粉煤灰颗粒内部的扩散控制;该吸附符合Langmuir吸附等温方程,随吸附温度升高,饱和吸附量下降,298K下的饱和吸附量可达526.32mg/g,是自发进行的放热反应过程.

  17. Multiphysics coupling between periodic gear mesh excitation and input/output fluctuating torques: Application to a roots vacuum pump

    Science.gov (United States)

    Garambois, Pierre; Donnard, Guillaume; Rigaud, Emmanuel; Perret-Liaudet, Joël

    2017-09-01

    This paper presents the analysis of multiphysics coupling between periodic gear mesh excitation and upstream/downstream fluctuating loads using an iterative spectral methodology. This one is based on the resolution of the parametric equations of motion in the spectral domain. Its efficiency makes possible to treat both low and high frequency excitations for systems having a large number of degrees-of-freedom. The different excitation sources, the dynamic coupled equations of motion, the spectral methodology and the iterative resolution principle are described. The dynamic responses of a roots vacuum pump for which the spur gear high mesh frequency parametric excitation is coupled with a low fluidic drag torque frequency. The coupling between excitations generates a frequency enrichment of the dynamic response which is reflected on waterfall plots by emergence of numerous sidebands around harmonics of the mesh frequency.

  18. Knowledge Management Capabilities Rubrics

    Directory of Open Access Journals (Sweden)

    Azizah B.A. Rahman

    2011-01-01

    Full Text Available Problem statement: Recently researchers discerned the vitality and importance of Knowledge Management Capabilities (KMC evaluation in organizations. In fact evaluation of KMC helps to prevent failure in Knowledge Management (KM projects. Approach: One of the most popular methods in the phase of evaluating KMC is Fuzzy method which evaluates seven attributes of KMC. Fuzzy needs KM experts to give their opinion about these attributes as input data. However in some organizations these experts are not available. Results: Therefore in this study a rubric matrix is developed as an assessment tool with ordered rank (very high, medium and very low of descriptive characteristics of criteria (seven attributes that organizations wish to evaluate. Conclusion: This rubric is applicable for members of an organization which are not familiar completely with KMC and also will be maintained by analyzing and surveying many different researches.

  19. PHOBOS physics capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Baker, M.D. [Massachusetts Institute of Technology, Cambridge, MA (United States)

    1995-07-15

    PHOBOS is the name of a detector and of a research program to study systematically the physics of relativistic heavy-ion collisions over a large range of impact parameters and nuclear species. Collisions with a center mass energy of 200 A GeV at RHIC are expected to produce the highest energy densities ever accessible in the laboratory. In this writeup, the authors outline the physics capabilities of the PHOBOS detector and describe the detector design in terms of the general philosophy behind the PHOBOS research program. In order to make the discussion concrete, they then focus on two specific examples of physics measurements that they plan to make at RHIC: dN/d{eta} for charged particles and the mass spectrum from {phi} {yields} K{sup +}K{sup {minus}} decays.

  20. A fully coupled Thermo-Hydro-Mechanical Double Porosity Formulation for Modeling Multiphysics Problems in Geological Media

    Science.gov (United States)

    Sanchez, M. J.; Gens, A.; Jarecki, Z.; Olivella, S.

    2012-12-01

    This work presents a coupled Thermo-Hydro-Mechanical (THM) formulation developed to handle multiphysic problems in porous media with two dominant void levels. The proposed framework assumes the presence of two porous media linked through a mass transfer term between them. In many cases, the use of a double porosity formulation is more realistic because it is possible to take explicitly into account the different physical phenomena that take place in each void level, and also their mutual interactions. The formulation is especially suitable for cases in which the material exhibits a strong coupling between the mechanical and the hydraulic problem in both media. The problem is approached using a multi-phase, multi-species formulation that expresses mathematically the main coupled thermo-hydro-mechanical phenomena in terms of: balance equations, constitutive equations and equilibrium restrictions. In its more general form, the proposed approach allows the consideration of multiphase flow in the two pore levels coupled with the mechanical problem. The formulation presented is quite open and general, and able to incorporate different constitutive laws for each basic structural level considered; for the mechanical, hydraulic and thermal problems. The double structure formulation has been implemented in the finite element program CODE_BRIGHT and it has been used to analyze a variety of engineering problems associated with the design of radioactive waste disposal in deep geological media and petroleum engineering problems. This work presents two case studies; one is related to oil production in a heterogeneous reservoir, and the other case focuses on the analysis of a repository for nuclear waste in a clayed formation. Both cases show the potential of the proposed formation to tackle coupled multiphysics problems in porous media.

  1. Grid Mapping Method of Multi-physics Coupled Modeling for Near Space Vehicle%临近空间飞行器多物理场耦合建模的网格映射方法

    Institute of Scientific and Technical Information of China (English)

    刘璟; 王玲; 胡东飞; 铁鸣; 吴旭生

    2012-01-01

    临近空间飞行器的研制面临许多复杂的问题和挑战,涉及总体、气动、结构、控制、防热、动力等多个学科和专业领域的相互作用、高度耦合的子系统.全系统、全流程的仿真验证与性能评估能够为设计工作提供重要依据,缩短研制周期.而气动、结构、防热等专业的仿真建模和模型解算基于有限体积法或有限元方法,依赖于不同的工具软件,且网格的划分方法不同.本文研究了临近空间高超声速飞行器多物理场耦合建模方法,研究并实现了异构网格耦合界面之间与耦合域之间的信息传递方法,从而实现了临近空间高超声速飞行器的多物理场耦合建模与仿真.%The development of near space vehicle is confronting many complex problems and challenges, involving many different subsystems which are highly interactive and coupled, such as overall design, aerodynamics , structure, thermal protection, control, dynamics and so on. The simulation validation and performance evaluation based on whole system and whole flow can provide important gist for the design, also accelerating the developing cycle. However, the simulation modeling and computation of subjects such as aerodynamics, structure and thermal protection are based on the finite volume method or the finite element method, depending on different software tools, and the partition methods of mesh are different as well. The coupled modeling method of multi-physics in the field of near space hypersonic vehicle is researched by implementing the method of message-passing which involves coupling interfaces of heterogeneous mesh and coupled region. The method of coupling modeling and simulation is implemented, which involves multi-physics in the fields of near space hypersonic vehicle.

  2. Ductile damage prediction in metal forming processes: Advanced modeling and numerical simulation

    Science.gov (United States)

    Saanouni, K.

    2013-05-01

    This paper describes the needs required in modern virtual metal forming including both sheet and bulk metal forming of mechanical components. These concern the advanced modeling of thermo-mechanical behavior including the multiphysical phenomena and their interaction or strong coupling, as well as the associated numerical aspects using fully adaptive simulation strategies. First a survey of advanced constitutive equations accounting for the main thermomechanical phenomena as the thermo-elasto-plastic finite strains with isotropic and kinematic hardenings fully coupled with ductile damage will be presented. Only the macroscopic phenomenological approach with state variables (monoscale approach) will be discussed in the general framework of the rational thermodynamics for generalized micromorphic continua. The micro-macro (multi-scales approach) in the framework of polycrystalline inelasticity is not presented here for the sake of shortness but will be presented during the oral presentation. The main numerical aspects related to the resolution of the associated initial and boundary value problem will be outlined. A fully adaptive numerical methodology will be briefly described and some numerical examples will be given in order to show the high predictive capabilities of this adaptive methodology for virtual metal forming simulations.

  3. CFD Simulation of Melting and Solidification of PCM in Thermal Energy Storage Systems of Different Geometry

    Science.gov (United States)

    Arena, S.; Cau, G.; Palomba, C.

    2015-11-01

    At the Department of Mechanical, Chemical and Materials Engineering of the University of Cagliari an experimental and numerical research project has begun with the aim of developing highly efficient thermal energy storage (TES) systems using phase change materials (PCM) of particular interest in concentrating small-medium scale solar power (CSP) applications. The present work aims to simulate the melting and solidification processes in containing boxes and heat transfer devices of different geometrical features which may constitute the elementary cell of a more complex TES system. Two-dimensional axisymmetric numerical models, developed with COMSOL Multiphysics are considered and used to simulate TES, heat conduction and natural convection. The models are used to determine the temperature profile inside the PCM to identify which configurations are capable of enhancing thermal response between a solid wall and a PCM. The results obtained will be used for comparison with experimental data acquired from a pilot plant under construction in the DIMCM laboratories. At the current stage the laboratory is being brought to completion.

  4. Partnership for Edge Physics Simulation (EPSI)

    Energy Technology Data Exchange (ETDEWEB)

    Schroder, Peter [California Inst. of Technology, Pasadena, CA (United States)

    2015-02-11

    We propose to develop advanced simulation codes, based upon an extreme parallelism, first principles kinetic approach, to address the challenges associated with the edge region of magnetically confined plasmas. This work is relevant to both existing magnetic fusion facilities and essential for next-generation burning plasma experiments, such as ITER where success is critically dependent upon H-mode operation achieving an edge pedestal of sufficient height for good core plasma performance without producing deleterious large scale edge localized instabilities. The plasma edge presents a well-known set of multi-physics, multi-scale problems involving complex 3D magnetic geometry. Perhaps the greatest computational challenge is the lack of scale separation – temporal scales for drift waves, Alfven waves, ELM dynamics for example have strong overlap. Similar overlap occurs on the spatial scales for the ion poloidal gyro-radius, drift wave and pedestal width. The traditional approach of separating fusion problems into weakly interacting spatial or temporal domains clearly breaks down in the edge. A full kinetic model (full-f model) must be solved to understand and predict the edge physics including non-equilibrium thermodynamic issues arising from the magnetic topology (the open field lines producing a spatially sensitive velocity hole), plasma wall interactions, neutral and atomic physics. The plan here is to model these phenomena within a comprehensive first principles set of equations without the need for the insurmountable multiple-codes coupling issues by building on the XGC1 code developed under the SciDAC Proto-FSP Center for Plasma Edge Simulation (CPES). This proposal includes the critical participants in the XGC1 development. We propose enhancing the capability of XGC1 by including all the important turbulence physics contained in kinetic ion and electron electromagnetic dynamics, by extending the PIC technology to incorporate several positive features found

  5. Developing Collaborative Product Development Capabilities

    DEFF Research Database (Denmark)

    Mahnke, Volker; Tran, Yen

    2012-01-01

    Collaborative product development capabilities support a company’s product innovation activities. In the context of the fast fashion sector, this paper examines the development of the product development capabilities (PDC) that align product development capabilities in a dual innovation context, ......-level, simultaneous learning processes and highlight the role of human agency in capability development with partners. Building on our analyses, we advance propositions for future research and managerial practices on developing dynamic collaboration capabilities....

  6. LHC Capabilities for Quarkonia

    CERN Document Server

    Petrushanko, Sergey

    2008-01-01

    The measurement of the charmonium and bottomonium resonances in nucleus-nucleus collisions provides crucial information on high-density QCD matter. First, the suppression of quarkonia production is generally agreed to be one of the most direct probes of quark-gluon plasma formation. The observation of anomalous J/$\\psi$ suppression at the CERN-SPS and at RHIC is well established but the clarification of some important remaining questions requires equivalent studies of the $\\Upsilon$ family, only possible at the LHC energies. Second, the production of heavy-quarks proceeds mainly via gluon-gluon fusion processes and, as such, is sensitive to saturation of the gluon density at low-x in the nucleus. Measured departures from the expected vacuum quarkonia cross-sections in Pb+Pb collisions at the LHC will thus provide valuable information not only on the thermodynamical state of the produced partonic medium, but also on the initial-state modifications of the nuclear parton distribution functions. The capabilities ...

  7. Three Dimensional Thermal Modeling of Li-Ion Battery Pack Based on Multiphysics and Calorimetric Measurement

    DEFF Research Database (Denmark)

    Khan, Mohammad Rezwan; Kær, Søren Knudsen

    2016-01-01

    . Inside the battery cells in the pack a lumped value of heat generation (HG), that works as a volumetric heat source, is used. The measured HG stems from the cell level isothermal calorimeter experiment. The batteries inside the pack stay in the same initial thermal state in the simulation case. The pack...... is simulated to find the temperature gradient over the pack surfaces. Moreover, the temperature evolution results are simulated. It is demonstrated that the developed pack model can provide the thermal spatio-temporal behaviour with great detail. The result helps to understand the thermal behavior of the cells...

  8. An Object Oriented and High Performance Platform for Aerothermodynamics Simulation

    OpenAIRE

    Lani, Andrea

    2008-01-01

    This thesis presents the author's contribution to the design and implementation of COOLFluiD,an object oriented software platform for the high performance simulation of multi-physics phenomena on unstructured grids. In this context, the final goal has been to provide a reliable tool for handling high speed aerothermodynamic applications. To this end, we introduce a number of design techniques that have been developed in order to provide the framework with flexibilityand reusability, allowing ...

  9. Recent simulation results of the magnetic induction tomography forward problem

    Directory of Open Access Journals (Sweden)

    Stawicki Krzysztof

    2016-06-01

    Full Text Available In this paper we present the results of simulations of the Magnetic Induction Tomography (MIT forward problem. Two complementary calculation techniques have been implemented and coupled, namely: the finite element method (applied in commercial software Comsol Multiphysics and the second, algebraic manipulations on basic relationships of electromagnetism in Matlab. The developed combination saves a lot of time and makes a better use of the available computer resources.

  10. ALEGRA-HEDP Multi-Dimensional Simulations of Z-pinch Related Physics

    Science.gov (United States)

    Garasi, Christopher J.

    2003-10-01

    The marriage of experimental diagnostics and computer simulations continues to enhance our understanding of the physics and dynamics associated with current-driven wire arrays. Early models that assumed the formation of an unstable, cylindrical shell of plasma due to wire merger have been replaced with a more complex picture involving wire material ablating non-uniformly along the wires, creating plasma pre-fill interior to the array before the bulk of the array collapses due to magnetic forces. Non-uniform wire ablation leads to wire breakup, which provides a mechanism for some wire material to be left behind as the bulk of the array stagnates onto the pre-fill. Once the bulk of the material has stagnated, electrical current can then shift back to the material left behind and cause it to stagnate onto the already collapsed bulk array mass. These complex effects impact the total radiation output from the wire array which is very important to application of that radiation for inertial confinement fusion. A detailed understanding of the formation and evolution of wire array perturbations is needed, especially for those which are three-dimensional in nature. Sandia National Laboratories has developed a multi-physics research code tailored to simulate high energy density physics (HEDP) environments. ALEGRA-HEDP has begun to simulate the evolution of wire arrays and has produced the highest fidelity, two-dimensional simulations of wire-array precursor ablation to date. Our three-dimensional code capability now provides us with the ability to solve for the magnetic field and current density distribution associated with the wire array and the evolution of three-dimensional effects seen experimentally. The insight obtained from these multi-dimensional simulations of wire arrays will be presented and specific simulations will be compared to experimental data.

  11. Drag &Drop, Multiphysics & Neural Net-based Lab-on-Chip Optimization Software Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall objective of this project is to develop a drag and drop, component library (fluidic lego) based, system simulation and optimization software for entire...

  12. Improved DFIG Capability during Asymmetrical Grid Faults

    DEFF Research Database (Denmark)

    Zhou, Dao; Blaabjerg, Frede

    2015-01-01

    , the capability of a 2 MW DFIG to ride through asymmetrical grid faults can be estimated at the existing design of the power electronics converter. Finally, a control scheme aimed to improve the DFIG capability is proposed and the simulation results validate its feasibility.......In the wind power application, different asymmetrical types of the grid fault can be categorized after the Y/d transformer, and the positive and negative components of a single-phase fault, phase-to-phase fault, and two-phase fault can be summarized. Due to the newly introduced negative and even...

  13. Impact of Personnel Capabilities on Organizational Innovation Capability

    DEFF Research Database (Denmark)

    Nielsen, Susanne Balslev; Momeni, Mostafa

    2016-01-01

    One of the most dynamic capabilities that lead to the strongest competitive advantage in the organizations is the innovation capability. Analysing the development of a firm’s innovation capability is an important research project, and can help organizations to achieve competitive advantage in thi...

  14. 海洋可控源电磁法对油气探测能力的仿真分析%Simulation and analysis on the prospecting capability of marine controlled-source electromagnetic methods to hydrocarbon reservoirs

    Institute of Scientific and Technical Information of China (English)

    刘长胜; 周逢道; 林君

    2012-01-01

    The marine controlled-source electromagnetic method (CSEM) is a new technology to detect subsea hydrocarbon reservoirs by electromagnetic fields of low frequency. Its prospecting capability is studied by numerical modeling in this paper. Based on 1D marine model, the electromagnetic responses on seafloor is calculated for different water depth environments and hydrocarbon reservoirs with various buried depth, thickness and resistivities. The biggest relative anomaly and corre- sponding absolute anomaly (i. e. amplitude difference) of electric fields for each buried depth, thickness and resistivity are plotted and the influence of these param- eters on the electromagnetic anomaly is analyzed. The simulation results show that the marine controlled-source electromagnetic method has great performance in sub- sea hydrocarbon reservoirs exploration. small resistivity difference or large buried Even the reservoirs of small thickness, depth in shallow sea environment can leadto considerable electromagnetic anomalies.' When other factors are same, the verti- cal impedance of oil layer decides the biggest electric anomaly. To achieve the opti- mal performance of marine CSEM, appropriate working frequency and receiver off- set are necessary. The study results will provide useful references for the geophysi- cal scheme design of future subsea hydrocarbon exploration.%海洋可控源电磁法是一种采用低频电磁场探测海底油气的新技术,通过仿真分析,研究了该方法对油气的探测能力。基于一维海洋模型,正演计算了不同水深、油气层埋深、油气层厚度和油气层电阻率时海底表面的电磁响应,绘制了最大相对异常幅度和相应的绝对异常幅度随油气埋深、厚度和电阻率变化的曲线,分析了这几种因素对电磁异常幅度的影响。仿真结果表明:海洋可控源电磁法对海底油气具有较强的探测能力,即使在浅海环境,埋深大、厚度薄或

  15. Effects of Biowastes Released by Mechanically Damaged Muscle Cells on the Propagation of Deep Tissue Injury: A Multiphysics Study.

    Science.gov (United States)

    Yao, Yifei; Da Ong, Lucas Xian; Li, Xiaotong; Wan, Kinlun; Mak, Arthur F T

    2017-03-01

    Deep tissue injuries occur in muscle tissues around bony prominences under mechanical loading leading to severe pressure ulcers. Tissue compression can potentially compromise lymphatic transport and cause accumulation of metabolic biowastes, which may cause further cell damage under continuous mechanical loading. In this study, we hypothesized that biowastes released by mechanically damaged muscle cells could be toxic to the surrounding muscle cells and could compromise the capability of the surrounding muscle cells to withstand further mechanical loadings. In vitro, we applied prolonged low compressive stress (PLCS) and short-term high compressive stress to myoblasts to cause cell damage and collected the biowastes released by the damaged cells under the respective loading scenarios. In silico, we used COMSOL to simulate the compressive stress distribution and the diffusion of biowastes in a semi-3D buttock finite element model. In vitro results showed that biowastes collected from cells damaged under PLCS were more toxic and could compromise the capability of normal myoblasts to resist compressive damage. In silico results showed that higher biowastes diffusion coefficient, higher biowastes release rate, lower biowastes tolerance threshold and earlier timeline of releasing biowastes would cause faster propagation of tissue damage. This study highlighted the importance of biowastes in the development of deep tissue injury to clinical pressure ulcers under prolonged skeletal compression.

  16. The Capability to Hold Property

    NARCIS (Netherlands)

    Claassen, Rutger|info:eu-repo/dai/nl/269266224

    2015-01-01

    This paper discusses the question of whether a capability theory of justice (such as that of Martha Nussbaum) should accept a basic “capability to hold property.” Answering this question is vital for bridging the gap between abstract capability theories of justice and their institutional implication

  17. The development of capability indicators

    NARCIS (Netherlands)

    Anand, Paul; Hunter, Graham; Carter, Ian; Dowding, Keith; Guala, Francesco; Van Hees, Martin

    2009-01-01

    This paper is motivated by sustained interest in the capabilities approach to welfare economics combined with the paucity of economic statistics that measure capabilities at the individual level. Specifically, it takes a much discussed account of the normatively desirable capabilities constitutive o

  18. The Capability to Hold Property

    NARCIS (Netherlands)

    Claassen, Rutger|info:eu-repo/dai/nl/269266224

    2015-01-01

    This paper discusses the question of whether a capability theory of justice (such as that of Martha Nussbaum) should accept a basic “capability to hold property.” Answering this question is vital for bridging the gap between abstract capability theories of justice and their institutional

  19. Solar mechanics thermal response capabilities.

    Energy Technology Data Exchange (ETDEWEB)

    Dobranich, Dean D.

    2009-07-01

    In many applications, the thermal response of structures exposed to solar heat loads is of interest. Solar mechanics governing equations were developed and integrated with the Calore thermal response code via user subroutines to provide this computational simulation capability. Solar heat loads are estimated based on the latitude and day of the year. Vector algebra is used to determine the solar loading on each face of a finite element model based on its orientation relative to the sun as the earth rotates. Atmospheric attenuation is accounted for as the optical path length varies from sunrise to sunset. Both direct and diffuse components of solar flux are calculated. In addition, shadowing of structures by other structures can be accounted for. User subroutines were also developed to provide convective and radiative boundary conditions for the diurnal variations in air temperature and effective sky temperature. These temperature boundary conditions are based on available local weather data and depend on latitude and day of the year, consistent with the solar mechanics formulation. These user subroutines, coupled with the Calore three-dimensional thermal response code, provide a complete package for addressing complex thermal problems involving solar heating. The governing equations are documented in sufficient detail to facilitate implementation into other heat transfer codes. Suggestions for improvements to the approach are offered.

  20. Capability-based computer systems

    CERN Document Server

    Levy, Henry M

    2014-01-01

    Capability-Based Computer Systems focuses on computer programs and their capabilities. The text first elaborates capability- and object-based system concepts, including capability-based systems, object-based approach, and summary. The book then describes early descriptor architectures and explains the Burroughs B5000, Rice University Computer, and Basic Language Machine. The text also focuses on early capability architectures. Dennis and Van Horn's Supervisor; CAL-TSS System; MIT PDP-1 Timesharing System; and Chicago Magic Number Machine are discussed. The book then describes Plessey System 25