WorldWideScience

Sample records for advanced hydraulic studies

  1. Advanced Hydraulic Studies on Enhancing Particle Removal

    DEFF Research Database (Denmark)

    He, Cheng

    The removal of suspended solids and attached pollutants is one of the main treatment processes in wastewater treatment. This thesis presents studies on the hydraulic conditions of various particle removal facilities for possible ways to increase their treatment capacity and performance by utilizing...... and improving hydraulic conditions. Unlike most traditional theses which usually focus only on one particular subject of study, this thesis contains four relatively independent studies which cover the following topics: a newly proposed particle settling enhancement plate, the redesign of the inlet zone...... of a high-flow rate clarifier, identify the hydraulic problems of an old partially functioned CSO facility and investigate possible ways to entirely eliminate untreated CSO by improving its hydraulic capacity and performance. In order to be easily understood, each part includes its own abstract...

  2. Advanced Performance Hydraulic Wind Energy

    Science.gov (United States)

    Jones, Jack A.; Bruce, Allan; Lam, Adrienne S.

    2013-01-01

    The Jet Propulsion Laboratory, California Institute of Technology, has developed a novel advanced hydraulic wind energy design, which has up to 23% performance improvement over conventional wind turbine and conventional hydraulic wind energy systems with 5 m/sec winds. It also has significant cost advantages with levelized costs equal to coal (after carbon tax rebate). The design is equally applicable to tidal energy systems and has passed preliminary laboratory proof-of-performance tests, as funded by the Department of Energy.

  3. Thermal-hydraulic studies of the Advanced Neutron Source cold source

    International Nuclear Information System (INIS)

    The Advanced Neutron Source (ANS), in its conceptual design phase at Oak Ridge National Laboratory, was to be a user-oriented neutron research facility producing the most intense steady-state flux of thermal and cold neutrons in the world. Among its many scientific applications, the production of cold neutrons was a significant research mission for the ANS. The cold neutrons come from two independent cold sources positioned near the reactor core. Contained by an aluminum alloy vessel, each cold source is a 410-mm-diam sphere of liquid deuterium that functions both as a neutron moderator and a cryogenic coolant. With nuclear heating of the containment vessel and internal baffling, steady-state operation requires close control of the liquid deuterium flow near the vessel's inner surface. Preliminary thermal-hydraulic analyses supporting the cold source design were performed with heat conduction simulations of the vessel walls and multidimensional computational fluid dynamics simulations of the liquid deuterium flow and heat transfer. This report presents the starting phase of a challenging program and describes the cold source conceptual design, the thermal-hydraulic feasibility studies of the containment vessel, and the future computational and experimental studies that were planned to verify the final design

  4. Development study on hydraulic three-dimensional seismic isolation system applied to advanced nuclear power plant. Development study on hydraulic rocking suppression system

    International Nuclear Information System (INIS)

    Three-dimensional (3D) seismic isolation devices have been developed for the base isolation system of the Fast Breeder Reactor (FBR) that is an advanced nuclear reactor power plant building. The developed seismic isolation system consists of the hydraulic type vertical springs with rocking suppression mechanism and the laminated rubber bearings for horizontal direction. The isolation performances, i.e. natural period, damping, and rocking-suppression, have already been evaluated by the technical feasibility study and performance tests on a system which consists of down-sized devices on the shaking table, but in the seismic simulation on the real size building with this system, high hydraulic pressure was generated by rocking-suppression device under an extremely large seismic motion. In this paper, it is reported the frictional characteristics on high hydraulic pressure condition from the experiments on the 1/2 size of real device. To improve the damping performance of rocking-suppression, the orifice was added to the cylinder. At first the linear seismic simulation model of the real size system was constructed and damping coefficient was optimized by using that linear model. Finally, the detailed nonlinear simulation model was constructed, and time history analysis under simultaneous horizontal and vertical seismic motion was carried out, and the damping performance of rocking-suppression device was verified. (author)

  5. Advanced Thermal Hydraulics Design of Commercial SFRs

    International Nuclear Information System (INIS)

    Prototype Fast Breeder Reactor (PFBR) is a 500 MWe pool type sodium cooled fast reactor, which is in an advanced stage of construction in India. As a follow-up to PFBR, six commercial sodium cooled fast reactors (Commercial SFR) of similar capacity are to be constructed, wherein the focus is improved economy and enhanced safety. These reactors are envisaged to have twin-unit concept. Design and construction experiences from PFBR provided the motivation to achieve an optimum design for the Commercial SFR with significant design changes. Some of the changes include, (i) provision of four primary pipes per primary sodium pump, (ii) inner vessel with single torus, (iii) dome shaped roof slab supported on reactor vault, (iv) machined thick plate rotating plugs, (v) reduced main vessel diameter with narrow-gap cooling baffles and (vi) safety vessel integrated with reactor vault. Advanced computational fluid dynamic studies have been performed towards thermal hydraulic design of these components. This paper covers thermal hydraulic design validation of the chosen options, including hot pool thermal hydraulics, influence of control plug shape on pool hydraulics, flow requirement for main vessel cooling, safety analysis of primary pipe rupture event and thermal management top shield and reactor vault. (author)

  6. Fundamental study on thermo-hydraulic phenomena concerning passive safety of advanced marine reactor

    International Nuclear Information System (INIS)

    The objective of this study is to investigate the thermo-hydraulic behavior of a fluid region confined in a rectangular parallelepiped cavity equipped with a heater and a cooler. The motivation of this study is to clarify a thermal buffer effect for an innovative marine nuclear reactor to realize passive safety. In the present study, experiments were carried out with conditions of laminar convection. Temperature and flow behavior was visualized by the liquid-crystal suspension method, by which the temperature distribution in liquid can be observed as a colored map. Thermal plumes from the heater and the cooler, global natural circulation in the cavity and thermal stratification were observed as elements of the complicated phenomena. Using a code which solves the Navier-Stokes and energy equations, numerical simulations under steady and unsteady condition were carried out to predict the experimental results for two-dimensional, laminar situations, and a good agreement was obtained. (author)

  7. Advances of study on thermal-hydraulic performance in tight-lattice rod bundles for reduced-moderation water reactors

    International Nuclear Information System (INIS)

    R and D project to investigate thermal-hydraulic performance in tight-lattice rod bundles for Reduced-Moderation Water Reactor (RMWR) is started at Japan Atomic Energy Research Institute in collaboration with power company, reactor vendors, universities since 2002. The RMWR can attain the favorable characteristics such as effective utilization of uranium resources, multiple recycling of plutonium, high burn-up and long operation cycle, based on matured LWR technologies. MOX fuel assemblies with tight lattice arrangement are used to increase the conversion ratio by reducing the moderation of neutron. Increasing the in-core void fraction also contributes to the reduction of neutron moderation. The confirmation of thermal-hydraulic feasibility is one of the most important R and D items for the RMWR because of the tight-lattice configuration. In this paper, we will show the R and D plan and describe some advances on experimental and analytical studies. The experimental study is performed mainly using large-scale (37-rod bundle) test facility and the analytical one aims to develop a predictable technology for geometry effects such as gap between rods, grid spacer configuration etc. using advanced 3-D two-phase flow simulation methods. Steady-state and transient critical power experiments are conducted with the test facility (Gap width between rods: 1.0 mm) and the experimental data reveal the feasibility of RMWR. (authors)

  8. Thermal hydraulic studies for passive heat transport systems relevant to advanced reactors

    International Nuclear Information System (INIS)

    Nuclear is the only non-green house gas generating power source that can replace fossil fuels and can be commercially deployed in large scale. However, the enormous developmental efforts and safety upgrades during the past six decades have somewhat eroded the economic competitiveness of water-cooled reactors which form the mainstay of the current nuclear power programme. Further, the introduction of the supercritical Rankine cycle and the gas turbine based advanced fuel cycles have enhanced the efficiency of fossil fired power plants (FPP) thereby reducing its greenhouse gas emissions. The ongoing development of ultra-supercritical and advanced ultra-supercritical turbines aims to further reduce the greenhouse gas emissions and economic competitiveness of FPPs. In the backdrop of these developments, the nuclear industry also initiated development of advanced nuclear power plants (NPP) with improved efficiency, sustainability and enhanced safety as the main goals. A review of the advanced reactor concepts being investigated currently reveals that excepting the SCWR, all other concepts use coolants other than water. The coolants used are lead, lead bismuth eutectic, liquid sodium, molten salts, helium and supercritical water. Besides, some of these are employing passive systems to transport heat from the core under normal operating conditions. In view of this, a study is in progress at BARC to examine the performance of simple passive systems using SC CO2, SCW, LBE and molten salts as the coolant. This paper deals with some of the recent results of these studies. The study focuses on the steady state, transient and stability behaviour of the passive systems with these coolants. (author)

  9. Nonelastomeric Rod Seals for Advanced Hydraulic Systems

    Science.gov (United States)

    Hady, W. F.; Waterman, A. W.

    1976-01-01

    Advanced high temperature hydraulic system rod sealing requirements can be met by using seals made of nonelastomeric (plastic) materials in applications where elastomers do not have adequate life. Exploratory seal designs were optimized for advanced applications using machinable polyimide materials. These seals demonstrated equivalent flight hour lives of 12,500 at 350 F and 9,875 at 400 F in advanced hydraulic system simulation. Successful operation was also attained under simulated space shuttle applications; 96 reentry thermal cycles and 1,438 hours of vacuum storage. Tests of less expensive molded plastic seals indicated a need for improved materials to provide equivalent performance to the machined seals.

  10. Thermal-Hydraulic Experiments and Modelling for Advanced Nuclear Reactor Systems

    International Nuclear Information System (INIS)

    The objectives of the project are to study thermal hydraulic characteristics of advanced nuclear reactor system for evaluating key thermal-hydraulic phenomena relevant to new safety concepts. To meet the research goal, several thermal hydraulic experiments were performed and related thermal hydraulic models were developed with the experimental data which were produced through the thermal hydraulic experiments. The Followings are main research topics: - Multi-dimensional Phenomena in a Reactor Vessel Downcomer - Condensation-induced Thermal Mixing in a Pool - Development of Thermal-Hydraulic Models for Two-Phase Flow - Construction of T-H Data Base

  11. International benchmark study of advanced thermal hydraulic safety analysis codes against measurements on IEA-R1 research reactor

    International Nuclear Information System (INIS)

    Highlights: • A set of advanced system thermal hydraulic codes are benchmarked against IFA of IEA-R1. • Comparative safety analysis of IEA-R1 reactor during LOFA by 7 working teams. • This work covers both experimental and calculation effort and presents new out findings on TH of RR that have not been reported before. • LOFA results discrepancies from 7% to 20% for coolant and peak clad temperatures are predicted conservatively. - Abstract: In the framework of the IAEA Coordination Research Project on “Innovative methods in research reactor analysis: Benchmark against experimental data on neutronics and thermal hydraulic computational methods and tools for operation and safety analysis of research reactors” the Brazilian research reactor IEA-R1 has been selected as reference facility to perform benchmark calculations for a set of thermal hydraulic codes being widely used by international teams in the field of research reactor (RR) deterministic safety analysis. The goal of the conducted benchmark is to demonstrate the application of innovative reactor analysis tools in the research reactor community, validation of the applied codes and application of the validated codes to perform comprehensive safety analysis of RR. The IEA-R1 is equipped with an Instrumented Fuel Assembly (IFA) which provided measurements for normal operation and loss of flow transient. The measurements comprised coolant and cladding temperatures, reactor power and flow rate. Temperatures are measured at three different radial and axial positions of IFA summing up to 12 measuring points in addition to the coolant inlet and outlet temperatures. The considered benchmark deals with the loss of reactor flow and the subsequent flow reversal from downward forced to upward natural circulation and presents therefore relevant phenomena for the RR safety analysis. The benchmark calculations were performed independently by the participating teams using different thermal hydraulic and safety

  12. International benchmark study of advanced thermal hydraulic safety analysis codes against measurements on IEA-R1 research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Hainoun, A., E-mail: pscientific2@aec.org.sy [Atomic Energy Commission of Syria (AECS), Nuclear Engineering Department, P.O. Box 6091, Damascus (Syrian Arab Republic); Doval, A. [Nuclear Engineering Department, Av. Cmdt. Luis Piedrabuena 4950, C.P. 8400 S.C de Bariloche, Rio Negro (Argentina); Umbehaun, P. [Centro de Engenharia Nuclear – CEN, IPEN-CNEN/SP, Av. Lineu Prestes 2242-Cidade Universitaria, CEP-05508-000 São Paulo, SP (Brazil); Chatzidakis, S. [School of Nuclear Engineering, Purdue University, West Lafayette, IN 47907 (United States); Ghazi, N. [Atomic Energy Commission of Syria (AECS), Nuclear Engineering Department, P.O. Box 6091, Damascus (Syrian Arab Republic); Park, S. [Research Reactor Design and Engineering Division, Basic Science Project Operation Dept., Korea Atomic Energy Research Institute (Korea, Republic of); Mladin, M. [Institute for Nuclear Research, Campului Street No. 1, P.O. Box 78, 115400 Mioveni, Arges (Romania); Shokr, A. [Division of Nuclear Installation Safety, Research Reactor Safety Section, International Atomic Energy Agency, A-1400 Vienna (Austria)

    2014-12-15

    Highlights: • A set of advanced system thermal hydraulic codes are benchmarked against IFA of IEA-R1. • Comparative safety analysis of IEA-R1 reactor during LOFA by 7 working teams. • This work covers both experimental and calculation effort and presents new out findings on TH of RR that have not been reported before. • LOFA results discrepancies from 7% to 20% for coolant and peak clad temperatures are predicted conservatively. - Abstract: In the framework of the IAEA Coordination Research Project on “Innovative methods in research reactor analysis: Benchmark against experimental data on neutronics and thermal hydraulic computational methods and tools for operation and safety analysis of research reactors” the Brazilian research reactor IEA-R1 has been selected as reference facility to perform benchmark calculations for a set of thermal hydraulic codes being widely used by international teams in the field of research reactor (RR) deterministic safety analysis. The goal of the conducted benchmark is to demonstrate the application of innovative reactor analysis tools in the research reactor community, validation of the applied codes and application of the validated codes to perform comprehensive safety analysis of RR. The IEA-R1 is equipped with an Instrumented Fuel Assembly (IFA) which provided measurements for normal operation and loss of flow transient. The measurements comprised coolant and cladding temperatures, reactor power and flow rate. Temperatures are measured at three different radial and axial positions of IFA summing up to 12 measuring points in addition to the coolant inlet and outlet temperatures. The considered benchmark deals with the loss of reactor flow and the subsequent flow reversal from downward forced to upward natural circulation and presents therefore relevant phenomena for the RR safety analysis. The benchmark calculations were performed independently by the participating teams using different thermal hydraulic and safety

  13. Advanced Control Strategies for Mobile Hydraulic Applications

    OpenAIRE

    Cristofori, Davide

    2013-01-01

    Mobile hydraulic machines are affected by numerous undesired dynamics, mainly discontinuous motion and vibrations. Over the years, many methods have been developed to limit the extent of those undesired dynamics and improve controllability and safety of operation of the machine. However, in most of the cases, today's methods do not significantly differ from those developed in a time when electronic controllers were slower and less reliable than they are today. This dissertation addresses t...

  14. Thermal-Hydraulic Experiments and Modelling for Advanced Nuclear Reactor Systems

    Energy Technology Data Exchange (ETDEWEB)

    Song, C. H.; Chung, M. K.; Park, C. K. and others

    2005-04-15

    The objectives of the project are to study thermal hydraulic characteristics of reactor primary system for the verification of the reactor safety and to evaluate new safety concepts of new safety design features. To meet the research goal, several thermal hydraulic experiments were performed and related thermal hydraulic models were developed with the experimental data which were produced through the thermal hydraulic experiments. Followings are main research topics; - Multi-dimensional Phenomena in a Reactor Vessel Downcomer - Condensation Load and Thermal Mixing in the IRWST - Development of Thermal-Hydraulic Models for Two-Phase Flow - Development of Measurement Techniques for Two-Phase Flow - Supercritical Reactor T/H Characteristics Analysis From the above experimental and analytical studies, new safety design features of the advanced power reactors were verified and lots of the safety issues were also resolved.

  15. Thermal hydraulic R and D of Chinese advanced reactors

    International Nuclear Information System (INIS)

    The Chinese government sponsors a program of research, development, and demonstration related to advanced reactors, both small modular reactors and larger systems. These advanced reactors encompass innovative reactor concepts, such as CAP1400 - Chinese large advanced passive pressurized water reactor, Hualong one - Chinese large advanced active and passive pressurized water reactor, ACP100 - Chinese small modular reactor, SCWR- R and D of super critical water-cooled reactor in China, CLEAR - Chinese lead-cooled fast reactor, TMSR - Chinese Thorium molten-salt reactor. The thermal hydraulic R and D of those reactors are summarised. (J.P.N.)

  16. Advanced thermal hydraulic method using 3x3 pin modeling

    International Nuclear Information System (INIS)

    Advanced thermal hydraulic methods are being developed as part of the US DOE sponsored Nuclear Hub program called CASL (Consortium for Advanced Simulation of LWRs). One of the key objectives of the Hub program is to develop a multi-physics tool which evaluates neutronic, thermal hydraulic, structural mechanics and nuclear fuel rod performance in rod bundles to support power uprates, increased burnup/cycle length and life extension for US nuclear plants. Current design analysis tools are separate and applied in series using simplistic models and conservatisms in the analysis. In order to achieve key Nuclear Hub objectives a higher fidelity, multi-physics tool is needed to address the challenge problems that limit current reactor performance. This paper summarizes the preliminary development of a multi-physics tool by performing 3x3 pin modeling and making comparisons to available data. (author)

  17. Kuala Kemaman hydraulic model study

    International Nuclear Information System (INIS)

    There The problems facing the area of Kuala Kemaman are siltation and erosion at shoreline. The objectives of study are to assess the best alignment of the groyne alignment, to ascertain the most stable shoreline regime and to investigate structural measures to overcome the erosion. The scope of study are data collection, wave analysis, hydrodynamic simulation and sediment transport simulation. Numerical models MIKE 21 are used - MIKE 21 NSW, for wind-wave model, which describes the growth, decay and transformation of wind-generated waves and swell in nearshore areas. The study takes into account effects of refraction and shoaling due to varying depth, energy dissipation due to bottom friction and wave breaking, MIKE 21 HD - modelling system for 2D free-surface flow which to stimulate the hydraulics phenomena in estuaries, coastal areas and seas. Predicted tidal elevation and waves (radiation stresses) are considered into study while wind is not considered. MIKE 21 ST - the system that calculates the rates of non-cohesive (sand) sediment transport for both pure content and combined waves and current situation

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

    International Nuclear Information System (INIS)

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

  19. Advanced modelling and numerical strategies in nuclear thermal-hydraulics

    International Nuclear Information System (INIS)

    The first part of the lecture gives a brief review of the current status of nuclear thermal hydraulics as it forms the basis of established system codes like TRAC, RELAP5, CATHARE or ATHLET. Specific emphasis is given to the capabilities and limitations of the underlying physical modelling and numerical solution strategies with regard to the description of complex transient two-phase flow and heat transfer conditions as expected to occur in PWR reactors during off-normal and accident conditions. The second part of the lecture focuses on new challenges and future needs in nuclear thermal-hydraulics which might arise with regard to re-licensing of old plants using bestestimate methodologies or the design and safety analysis of Advanced Light Water Reactors relying largely on passive safety systems. In order to meet these new requirements various advanced modelling and numerical techniques will be discussed including extended wellposed (hyperbolic) two-fluid models, explicit modelling of interfacial area transport or higher order numerical schemes allowing a high resolution of local multi-dimensional flow processes.(author)

  20. Advancement of experimentation for measuring hydraulic conductivity of bentonite using high-pressure consolidation test apparatus

    International Nuclear Information System (INIS)

    In the geological disposal facility of high-level radioactive wastes, it is important to grasp the hydraulic conductivity characteristic of bentonite. The purpose of this study is the advancement of the examination method for the measurement of a more reliable hydraulic conductivity using high-pressure consolidation test apparatus (maximum consolidation pressure 10MPa). Consequently, it succeeded in improving the reliability of data by raising the resolution of displacement used for an examination, increasing to 80 the number of measurement data for 2 minutes after making each consolidation pressure act on the occasion of measurement and adopting the data of a high consolidation pressure (more than 5.88MPa) stage. (author)

  1. Thermal hydraulic analysis of advanced Pb-Bi cooled NPP using natural circulation

    Science.gov (United States)

    Novitrian, Su'ud, Zaki; Waris, Abdul

    2012-06-01

    We present thermal hydraulic analysis for a low power advanced nuclear reactor cooled by lead-bismuth eutectic. In this work is to study the thermal hydraulic analysis of a low power SPINNOR (Small Power Reactor, Indonesia, No On-site Refuelling) reactor with 125 MWth which a design a core with very small volume and fuel column height, resulting in a negative coolant temperature coefficient and very low channel pressure drop. And also at full power the heat can be completely removed by natural circulation in the primary circuit, thus eliminating the needs for pumps.

  2. MAAP thermal-hydraulic qualification studies

    International Nuclear Information System (INIS)

    The MAAP Thermal-Hydraulic Qualification and Application Project has as its objective to identify those thermal-hydraulic phenomena modeled in MAAP which are important in predicting severe accident sequences and to qualify those models. This report discusses sensitivity studies performed with MAAP to determine the sensitivity of the code to important input and modeling parameters and comparison of MAAP predictions to test data and independent predictions by other computer programs

  3. Hydraulics.

    Science.gov (United States)

    Decker, Robert L.; Kirby, Klane

    This curriculum guide contains a course in hydraulics to train entry-level workers for automotive mechanics and other fields that utilize hydraulics. The module contains 14 instructional units that cover the following topics: (1) introduction to hydraulics; (2) fundamentals of hydraulics; (3) reservoirs; (4) lines, fittings, and couplers; (5)…

  4. Thermal hydraulic evaluation of advanced wire-wrapped assemblies

    International Nuclear Information System (INIS)

    The thermal-hydraulic analyses presented in this report are based on application of the subchannel concept in association with the use of bulk parameters for coolant velocity and coolant temperature within a subchannel. The interactions between subchannels are due to turbulent interchange, pressure-induced diversion crossflow, directed sweeping crossflow induced by the helical wire wrap, and transverse thermal conduction. The FULMIX-II computer program was successfully developed to perform the steady-state temperature predictions for LMFBR fuel assemblies with the reference straight-start design and the advanced wire-wrap designs. Predicted steady-state temperature profiles are presented for a typical CRBRP 217-rod wire-wrapped assembly with the selected wire-wrap designs

  5. Fort St. Vrain hydraulic power system study

    International Nuclear Information System (INIS)

    This report prepared for the United States Department of Energy under Contract Number DEAC03-80SF11440, contains the results of the Fort St. Vrain Hydraulic Power System (System 91) engineering study. The major objectives of this study were to evaluate, analyze, and recommend corrective actions to resolve HTGR (High Temperature Gas Cooled Reactor) operational problems and equipment performance problems in the hydraulic power system at the Fort St. Vrain Nuclear Generating Station. The recommended corrective actions for each subject are subdivided where appropriate, into two categories: modifications suggested for implementation at Fort St. Vrain and modifications suggested for consideration in the design of future HTGRs

  6. Advanced Hydraulic Fracturing Technology for Unconventional Tight Gas Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Stephen Holditch; A. Daniel Hill; D. Zhu

    2007-06-19

    The objectives of this project are to develop and test new techniques for creating extensive, conductive hydraulic fractures in unconventional tight gas reservoirs by statistically assessing the productivity achieved in hundreds of field treatments with a variety of current fracturing practices ranging from 'water fracs' to conventional gel fracture treatments; by laboratory measurements of the conductivity created with high rate proppant fracturing using an entirely new conductivity test - the 'dynamic fracture conductivity test'; and by developing design models to implement the optimal fracture treatments determined from the field assessment and the laboratory measurements. One of the tasks of this project is to create an 'advisor' or expert system for completion, production and stimulation of tight gas reservoirs. A central part of this study is an extensive survey of the productivity of hundreds of tight gas wells that have been hydraulically fractured. We have been doing an extensive literature search of the SPE eLibrary, DOE, Gas Technology Institute (GTI), Bureau of Economic Geology and IHS Energy, for publicly available technical reports about procedures of drilling, completion and production of the tight gas wells. We have downloaded numerous papers and read and summarized the information to build a database that will contain field treatment data, organized by geographic location, and hydraulic fracture treatment design data, organized by the treatment type. We have conducted experimental study on 'dynamic fracture conductivity' created when proppant slurries are pumped into hydraulic fractures in tight gas sands. Unlike conventional fracture conductivity tests in which proppant is loaded into the fracture artificially; we pump proppant/frac fluid slurries into a fracture cell, dynamically placing the proppant just as it occurs in the field. From such tests, we expect to gain new insights into some of the critical

  7. Advanced model structures applied to system identification of a servo- hydraulic test rig

    Directory of Open Access Journals (Sweden)

    P. Czop

    2010-07-01

    Full Text Available Purpose: This paper deals with a method for the parametric system identification of a nonlinear system to obtain its parametric representation using a linear transfer function. Such representation is applicable in off-line profile correction methods minimizing the error between a reference input signal and a signal performed by the test rig. In turn, a test signal can be perfectly tracked by a servo-hydraulic test rig. This is the requirement in massive production where short test sequences are repeated to validate the products.Design/methodology/approach: A numerical and experimental case studies are presented in the paper. The numerical study presents a system identification process of a nonlinear system consisting of a linear transfer function and a nonlinear output component, being a static function. The experimental study presents a system identification process of a nonlinear system which is a servo-hydraulic test rig. The simulation data has been used to illustrate the feasibility study of the proposed approach, while the experimental data have been used to validate advanced model structures under operational conditions.Findings: The advanced model structures confirmed their better performance by means of the model fit in the time domain.Research limitations/implications: The method applies to analysis of such mechanical and hydraulic systems for which measurements are corrupted by residual harmonic disturbances resulting from system nonlinearities.Practical implications: The advanced model structures are intended to be used as inverse models in off-line signal profile correction.Originality/value: The results state the foundation for the off-line parametric error cancellation method which aims in improving tracking of load signals on servo-hydraulic test rigs.

  8. NEPTUNE: A new software platform for advanced nuclear thermal hydraulics

    International Nuclear Information System (INIS)

    The NEPTUNE project constitutes the thermal-hydraulic part of the long-term Electricite de France and Commissariat a l'Energie Atomique joint research and development program for the next generation of nuclear reactor simulation tools. This program is also financially supported by the Institut de Radioprotection et Surete Nucleaire and AREVA NP. The project aims at developing a new software platform for advanced two-phase flow thermal hydraulics covering the whole range of modeling scales and allowing easy multi-scale and multidisciplinary calculations. NEPTUNE is a fully integrated project that covers the following fields: software development, research in physical modeling and numerical methods, development of advanced instrumentation techniques, and performance of new experimental programs. The analysis of the industrial needs points out that three main simulation scales are involved. The system scale is dedicated to the overall description of the reactor. The component or subchannel scale allows three-dimensional computations of the main components of the reactors: cores, steam generators, condensers, and heat exchangers. The current generation of system and component codes has reached a very high level of maturity for industrial applications. The third scale, computational fluid dynamics (CFD) in open medium, allows one to go beyond the limits of the component scale for a finer description of the flows. This scale opens promising perspectives for industrial simulations, and the development and validation of the NEPTUNE CFD module have been a priority since the beginning of the project. It is based on advanced physical models (two-fluid or multi field model combined with interfacial area transport and two-phase turbulence) and modern numerical methods (fully unstructured finite volume solvers). For the system and component scales, prototype developments have also started, including new physical models and numerical methods. In addition to scale

  9. Hydraulics Studies In Port Conception

    OpenAIRE

    Hermite, Sophie

    2015-01-01

    In the Maritime Works Engineering department of Saipem, studies have been carried out to design an extension to an existing LNG export facility. The scope of work comprises the design of a jetty on piles. For this purpose, wave propagation and ship mooring computations have been performed, as well as shore protection and abutment studies. These studies were preceded by meteocean site data and bathymetry analysis.

  10. Study on Characteristics of Hydraulic Servo System for Force Control of Hydraulic Robots

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyo-gon; Han, Changsoo [Hanyang University, Seoul (Korea, Republic of); Lee, Jong-won [Korea University of Science and Technology, Seoul (Korea, Republic of); Park, Sangdeok [Korea Institute of Industrial Technology, Seoul (Korea, Republic of)

    2015-02-15

    Because a hydraulic actuator has high power and force densities, this allows the weight of the robot's limbs to be reduced. This allows for good dynamic characteristics and high energy efficiency. Thus, hydraulic actuators are used in some exoskeleton robots and quadrupedal robots that require high torque. Force control is useful for robot compliance with a user or environment. However, force control of a hydraulic robot is difficult because a hydraulic servo system is highly nonlinear from a control perspective. In this study, a nonlinear model was used to develop a simulation program for a hydraulic servo system consisting of a servo valve, transmission lines, and a cylinder. The problems and considerations with regard to the force control performance for a hydraulic servo system were investigated. A force control method using the nonlinear model was proposed, and its effect was evaluated with the simulation program.

  11. Study on Characteristics of Hydraulic Servo System for Force Control of Hydraulic Robots

    International Nuclear Information System (INIS)

    Because a hydraulic actuator has high power and force densities, this allows the weight of the robot's limbs to be reduced. This allows for good dynamic characteristics and high energy efficiency. Thus, hydraulic actuators are used in some exoskeleton robots and quadrupedal robots that require high torque. Force control is useful for robot compliance with a user or environment. However, force control of a hydraulic robot is difficult because a hydraulic servo system is highly nonlinear from a control perspective. In this study, a nonlinear model was used to develop a simulation program for a hydraulic servo system consisting of a servo valve, transmission lines, and a cylinder. The problems and considerations with regard to the force control performance for a hydraulic servo system were investigated. A force control method using the nonlinear model was proposed, and its effect was evaluated with the simulation program

  12. Advanced drilling systems study.

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, Kenneth G.; Livesay, Billy Joe; Finger, John Travis (Livesay Consultants, Encintas, CA)

    1996-05-01

    This report documents the results of a study of advanced drilling concepts conducted jointly for the Natural Gas Technology Branch and the Geothermal Division of the U.S. Department of Energy. A number of alternative rock cutting concepts and drilling systems are examined. The systems cover the range from current technology, through ongoing efforts in drilling research, to highly speculative concepts. Cutting mechanisms that induce stress mechanically, hydraulically, and thermally are included. All functions necessary to drill and case a well are considered. Capital and operating costs are estimated and performance requirements, based on comparisons of the costs for alternative systems to conventional drilling technology, are developed. A number of problems common to several alternatives and to current technology are identified and discussed.

  13. 23 CFR 650.111 - Location hydraulic studies.

    Science.gov (United States)

    2010-04-01

    ... § 650.111 (c) and (d) shall be summarized in environmental review documents prepared pursuant to 23 CFR... 23 Highways 1 2010-04-01 2010-04-01 false Location hydraulic studies. 650.111 Section 650.111... BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains §...

  14. Advanced hydraulic fracturing methods to create in situ reactive barriers

    International Nuclear Information System (INIS)

    This article describes the use of hydraulic fracturing to increase permeability in geologic formations where in-situ remedial action of contaminant plumes will be performed. Several in-situ treatment strategies are discussed including the use of hydraulic fracturing to create in situ redox zones for treatment of organics and inorganics. Hydraulic fracturing methods offer a mechanism for the in-situ treatment of gently dipping layers of reactive compounds. Specialized methods using real-time monitoring and a high-energy jet during fracturing allow the form of the fracture to be influenced, such as creation of assymmetric fractures beneath potential sources (i.e. tanks, pits, buildings) that should not be penetrated by boring. Some examples of field applications of this technique such as creating fractures filled with zero-valent iron to reductively dechlorinate halogenated hydrocarbons, and the use of granular activated carbon to adsorb compounds are discussed

  15. Hydraulic fracture model comparison study: Complete results

    Energy Technology Data Exchange (ETDEWEB)

    Warpinski, N.R. [Sandia National Labs., Albuquerque, NM (United States); Abou-Sayed, I.S. [Mobil Exploration and Production Services (United States); Moschovidis, Z. [Amoco Production Co. (US); Parker, C. [CONOCO (US)

    1993-02-01

    Large quantities of natural gas exist in low permeability reservoirs throughout the US. Characteristics of these reservoirs, however, make production difficult and often economic and stimulation is required. Because of the diversity of application, hydraulic fracture design models must be able to account for widely varying rock properties, reservoir properties, in situ stresses, fracturing fluids, and proppant loads. As a result, fracture simulation has emerged as a highly complex endeavor that must be able to describe many different physical processes. The objective of this study was to develop a comparative study of hydraulic-fracture simulators in order to provide stimulation engineers with the necessary information to make rational decisions on the type of models most suited for their needs. This report compares the fracture modeling results of twelve different simulators, some of them run in different modes for eight separate design cases. Comparisons of length, width, height, net pressure, maximum width at the wellbore, average width at the wellbore, and average width in the fracture have been made, both for the final geometry and as a function of time. For the models in this study, differences in fracture length, height and width are often greater than a factor of two. In addition, several comparisons of the same model with different options show a large variability in model output depending upon the options chosen. Two comparisons were made of the same model run by different companies; in both cases the agreement was good. 41 refs., 54 figs., 83 tabs.

  16. Hydraulic fracturing: insights from field, lab, and numerical studies

    Science.gov (United States)

    Walsh, S. D.; Johnson, S.; Fu, P.; Settgast, R. R.

    2011-12-01

    Hydraulic fracturing has become an increasingly important technique in stimulating reservoirs for gas, oil, and geothermal energy production. In use commercially since the 1950's, the technique has been widely lauded, when combined with other techniques, for enabling the development of shale gas resources in the United States, providing a valuable and extensive source of domestic energy. However, the technique has also drawn a degree of notoriety from high-profile incidents involving contamination of drinking water associated with gas extraction operations in the Marcellus shale region. This work highlights some of the insights on the behavior of subsurface hydraulic fracturing operations that have been derived from field and laboratory observations as well as from numerical simulations. The sensitivity of fracture extent and orientation to parameters such as matrix material heterogeneity, presence and distribution of discontinuities, and stress orientation is of particular interest, and we discuss this in the context of knowledge derived from both observation and simulation. The limitations of these studies will also be addressed in terms of resolution, uncertainty, and assumptions as well as the balance of fidelity to cost, both in computation time (for numerical studies) and equipment / operation cost (for observational studies). We also identify a number of current knowledge gaps and propose alternatives for addressing those gaps. We especially focus on the role of numerical studies for elucidating key concepts and system sensitivities. The problem is inherently multi-scale in both space and time as well as highly coupled hydromechanically, and, in several applications, thermally as well. We will summarize the developments to date in analyzing these systems and present an approach for advancing the capabilities of our models in the short- to long-term and how these advances can help provide solutions to reduce risk and improve efficiency of hydraulic fracturing

  17. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Stefan Miska; Troy Reed; Ergun Kuru

    2004-09-30

    The Advanced Cuttings Transport Study (ACTS) was a 5-year JIP project undertaken at the University of Tulsa (TU). The project was sponsored by the U.S. Department of Energy (DOE) and JIP member companies. The objectives of the project were: (1) to develop and construct a new research facility that would allow three-phase (gas, liquid and cuttings) flow experiments under ambient and EPET (elevated pressure and temperature) conditions, and at different angle of inclinations and drill pipe rotation speeds; (2) to conduct experiments and develop a data base for the industry and academia; and (3) to develop mechanistic models for optimization of drilling hydraulics and cuttings transport. This project consisted of research studies, flow loop construction and instrumentation development. Following a one-year period for basic flow loop construction, a proposal was submitted by TU to the DOE for a five-year project that was organized in such a manner as to provide a logical progression of research experiments as well as additions to the basic flow loop. The flow loop additions and improvements included: (1) elevated temperature capability; (2) two-phase (gas and liquid, foam etc.) capability; (3) cuttings injection and removal system; (4) drill pipe rotation system; and (5) drilling section elevation system. In parallel with the flow loop construction, hydraulics and cuttings transport studies were preformed using drilling foams and aerated muds. In addition, hydraulics and rheology of synthetic drilling fluids were investigated. The studies were performed under ambient and EPET conditions. The effects of temperature and pressure on the hydraulics and cuttings transport were investigated. Mechanistic models were developed to predict frictional pressure loss and cuttings transport in horizontal and near-horizontal configurations. Model predictions were compared with the measured data. Predominantly, model predictions show satisfactory agreements with the measured data. As a

  18. The hydraulic bulge tester in fracture studies

    International Nuclear Information System (INIS)

    In this work the behavior of different metals under biaxial hydraulic bulging was studied in terms of fracture mechanics. Three different materials, namely: SIC aluminium, mild steel and copper were examined and their fracture behavior was assessed by introducing starter cracks in the test pieces in different ways before bulging. The pressure-volume relationships were obtained and the crack growth rates were measured during bulging at different elliptical die ratios (1,1.5,2 and 3). It was found that increasing the die ratio, with everything else remaining as before, resulted in a remarkable reduction to the volume and increase in the pressure and subsequently an increase in the crack growth rates of all materials. Double Edge Notched (DEN) specimen experiments were also conducted on the three materials to measure their fracture toughness and the results compared with those obtained from bulging experiments. (author)

  19. Study on buffering characteristics of hydraulic absorber

    International Nuclear Information System (INIS)

    Control rod hydraulic drive mechanism (CRHDM) is a new type of in-vessel control rod drive technology. Hydraulic absorber is one of the key parts of control rod hydraulic drive line. It is used to buffer control rod when the rod scrams to prevent the cross-blades of control rod from deformation and damage. Based on the working process of the hydraulic absorber, a theoretical model of the buffering process was established. Calculation results of the theoretical model agree well with the experiment results. The trend of pressure change in absorber cylinder, the displacement and velocity of the piston and buffering force during the buffering process were obtained from the calculation results of the theoretical model. Then influence parameters about cushioning characteristics were analyzed, which laid foundation for optimal design of the hydraulic absorber. (authors)

  20. Relevant thermal hydraulic aspects of advanced reactors design: status report

    International Nuclear Information System (INIS)

    This status report provides an overview on the relevant thermalhydraulic aspects of advanced reactor designs (e.g. ABWR, AP600, SBWR, EPR, ABB 80+, PIUS, etc.). Since all of the advanced reactor concepts are at the design stage, the information and data available in the open literature are still very limited. Some characteristics of advanced reactor designs are provided together with selected phenomena identification and ranking tables. Specific needs for thermalhydraulic codes together with the list of relevant and important thermalhydraulic phenomena for advanced reactor designs are summarized with the purpose of providing some guidance in development of research plans for considering further code development and assessment needs and for the planning of experimental programs

  1. Thermal-hydraulics numerical analyses of Pebble Bed Advanced High Temperature Reactor hot channel

    International Nuclear Information System (INIS)

    Background: The thermal hydraulics behavior of the Pebble Bed Advanced High Temperature Reactor (PB-AHTR) hot channel was studied. Purpose: We aim to analyze the thermal-hydraulics behavior of the PB-AHTR, such as pressure drop, temperature distribution of coolant and pebble bed as well as thermal removal capacity in the condition of loss of partial coolant. Methods: We used a modified FLUENT code which was coupled with a local non-equilibrium porous media model by introducing a User Defined Scalar (UDS) in the calculation domain of the reactor core and subjoining different resistance terms (Ergun and KTA) to calculate the temperature of coolant, solid phase of pebble bed and pebble center in the core. Results: Computational results showed that the resistance factor has great influence on pressure drop and velocity distribution, but less impact on the temperature of coolant, solid phase of pebble bed and pebble center. We also confirmed the heat removal capacity of the PB-AHTR in the condition of nominal and loss of partial coolant conditions. Conclusion: The numerical analyses results can provide a useful proposal to optimize the design of PB-AHTR. (authors)

  2. Development of a steady thermal-hydraulic analysis code for the China Advanced Research Reactor

    Institute of Scientific and Technical Information of China (English)

    TIAN Wenxi; QIU Suizheng; GUO Yun; SU Guanghui; JIA Dounan; LIU Tiancai; ZHANG Jianwei

    2007-01-01

    A multi-channel model steady-state thermalhydraulic analysis code was developed for the China Advanced Research Reactor (CARR). By simulating the whole reactor core, the detailed mass flow distribution in the core was obtained. The result shows that structure size plays the most important role in mass flow distribution, and the influence of core power could be neglected under singlephase flow. The temperature field of the fuel element under unsymmetrical cooling condition was also obtained, which is necessary for further study such as stress analysis, etc. Of the fuel element. At the same time, considering the hot channel effect including engineering factor and nuclear factor, calculation of the mean and hot channel was carried out and it is proved that all thermal-hydraulic parameters satisfy the "Safety design regulation of CARR".

  3. Thermal hydraulic studies of high temperature reactors

    International Nuclear Information System (INIS)

    The development of High Temperature Nuclear Reactors capable of supplying process heat at a temperature around 1273 K, is in Progress at BARC. These nuclear reactors are being developed with the objective of providing energy to facilitate combined production of hydrogen, electricity, and drinking water. The reject and waste heat in the overall energy scheme are utilised for electricity generation and desalination, respectively. Presently, technology development for a small power (100 kWth) Compact High Temperature Reactor (CHTR) capable of supplying high temperature process heat at 1273 K is being carried out. In addition conceptual details of a 10 MWth reactor supplying heat at 1273 K for commercial hydrogen production, are also being worked out. 3D CFD analysis of the CHTR reactor core has been carried out to estimate the core heat removal capability by natural circulation during normal operating conditions. PHOENICS, a generalized CFD code is used for the analysis. The full-scale core, including fuel tube, coolant channel, plenums, down comer, heat sink, moderator and reflector has been modeled and analysed in PHOENICS. Steady state analysis is carried out to find flow distribution in the coolant circuit and temperature distribution in the whole core. Analyses have also been carried out to simulate various operational transients and accidental conditions of the reactor. This paper deals with the detailed CFD analysis. The details on the selection of the appropriate turbulence model, turbulent Prandtl number and mesh distribution for the CFD analysis are described in the paper. The results of the steady state and transient analyses are also presented in the paper. Paper shows one of the results of 3D CFD analysis for CHTR core. This paper also deals with the core thermal hydraulic analysis of the conceptual design of the 10MWth High Temperature Pebble Bed Reactor. Preliminary thermal hydraulic analysis is carried out with FLiBe as the primary coolants. The

  4. Advanced hydraulic fracturing methods to create in situ reactive barriers

    Energy Technology Data Exchange (ETDEWEB)

    Murdoch, L. [FRx Inc., Cincinnati, OH (United States)]|[Clemson Univ., SC (United States); Siegrist, B. [Oak Ridge National Lab., TN (United States); Vesper, S. [Univ. of Cincinnati, OH (United States)] [and others

    1997-12-31

    Many contaminated areas consist of a source area and a plume. In the source area, the contaminant moves vertically downward from a release point through the vadose zone to an underlying saturated region. Where contaminants are organic liquids, NAPL may accumulate on the water table, or it may continue to migrate downward through the saturated region. Early developments of permeable barrier technology have focused on intercepting horizontally moving plumes with vertical structures, such as trenches, filled with reactive material capable of immobilizing or degrading dissolved contaminants. This focus resulted in part from a need to economically treat the potentially large volumes of contaminated water in a plume, and in part from the availability of construction technology to create the vertical structures that could house reactive compounds. Contaminant source areas, however, have thus far remained largely excluded from the application of permeable barrier technology. One reason for this is the lack of conventional construction methods for creating suitable horizontal structures that would place reactive materials in the path of downward-moving contaminants. Methods of hydraulic fracturing have been widely used to create flat-lying to gently dipping layers of granular material in unconsolidated sediments. Most applications thus far have involved filling fractures with coarse-grained sand to create permeable layers that will increase the discharge of wells recovering contaminated water or vapor. However, it is possible to fill fractures with other compounds that alter the chemical composition of the subsurface. One early application involved development and field testing micro-encapsulated sodium percarbonate, a solid compound that releases oxygen and can create aerobic conditions suitable for biodegradation in the subsurface for several months.

  5. Advanced hydraulic fracturing methods to create in situ reactive barriers

    International Nuclear Information System (INIS)

    Many contaminated areas consist of a source area and a plume. In the source area, the contaminant moves vertically downward from a release point through the vadose zone to an underlying saturated region. Where contaminants are organic liquids, NAPL may accumulate on the water table, or it may continue to migrate downward through the saturated region. Early developments of permeable barrier technology have focused on intercepting horizontally moving plumes with vertical structures, such as trenches, filled with reactive material capable of immobilizing or degrading dissolved contaminants. This focus resulted in part from a need to economically treat the potentially large volumes of contaminated water in a plume, and in part from the availability of construction technology to create the vertical structures that could house reactive compounds. Contaminant source areas, however, have thus far remained largely excluded from the application of permeable barrier technology. One reason for this is the lack of conventional construction methods for creating suitable horizontal structures that would place reactive materials in the path of downward-moving contaminants. Methods of hydraulic fracturing have been widely used to create flat-lying to gently dipping layers of granular material in unconsolidated sediments. Most applications thus far have involved filling fractures with coarse-grained sand to create permeable layers that will increase the discharge of wells recovering contaminated water or vapor. However, it is possible to fill fractures with other compounds that alter the chemical composition of the subsurface. One early application involved development and field testing micro-encapsulated sodium percarbonate, a solid compound that releases oxygen and can create aerobic conditions suitable for biodegradation in the subsurface for several months

  6. Hydraulic works study of Golfech cooling towers

    International Nuclear Information System (INIS)

    The GOLFECH Nuclear Power Plant cooling towers (PWR 2 x 1300 MWe), built by SCAM for EDF (French National Electricity Authority), have certain characteristics, including: tower height - 178.50 metres; shell support - made up of a profiled lintel resting on piles; cooled water recovery system installed immediately below the fill; and cold water basin built outside the cooling tower. This paper deals only with the hydraulic circuit design (warm water inlet, cooled water recovery, cooled water return) with particular emphasis on the limitations of conventional methods of hydraulic sizing and, the necessity to carry out tests using models in order to dimension such works

  7. Final design of a free-piston hydraulic advanced Stirling conversion system

    Science.gov (United States)

    Wallace, D. A.; Noble, J. E.; Emigh, S. G.; Ross, B. A.; Lehmann, G. A.

    1991-01-01

    Under the US Department of Energy's (DOEs) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for solar distributed receiver systems. The final design is described of an engineering prototype advanced Stirling conversion system (ASCS) with a free-piston hydraulic engine output capable of delivering about 25 kW of electric power to a utility grid. The free-piston Stirling engine has the potential for a highly reliable engine with long life because it has only a few moving parts, has noncontacting bearings, and can be hermetically sealed. The ASCS is designed to deliver maximum power per year over a range of solar input with a design life of 30 years (60,000 h). The system includes a liquid Nak pool boiler heat transport system and a free-piston Stirling engine with high-pressure hydraulic output, coupled with a bent axis variable displacement hydraulic motor and a rotary induction generator.

  8. Final design of a free-piston hydraulic advanced Stirling conversion system

    Science.gov (United States)

    Wallace, D. A.; Noble, J. E.; Emigh, S. G.; Ross, B. A.; Lehmann, G. A.

    Under the US Department of Energy's (DOEs) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for solar distributed receiver systems. The final design is described of an engineering prototype advanced Stirling conversion system (ASCS) with a free-piston hydraulic engine output capable of delivering about 25 kW of electric power to a utility grid. The free-piston Stirling engine has the potential for a highly reliable engine with long life because it has only a few moving parts, has noncontacting bearings, and can be hermetically sealed. The ASCS is designed to deliver maximum power per year over a range of solar input with a design life of 30 years (60,000 h). The system includes a liquid Nak pool boiler heat transport system and a free-piston Stirling engine with high-pressure hydraulic output, coupled with a bent axis variable displacement hydraulic motor and a rotary induction generator.

  9. EPA Study of Hydraulic Fracturing and Drinking Water Resources

    Science.gov (United States)

    In its FY2010 Appropriations Committee Conference Report, Congress directed EPA to study the relationship between hydraulic fracturing and drinking water, using: • Best available science • Independent sources of information • Transparent, peer-reviewed process • Consultatio...

  10. Study on thermal-hydraulics during a PWR reflood phase

    Energy Technology Data Exchange (ETDEWEB)

    Iguchi, Tadashi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-10-01

    In-core thermal-hydraulics during a PWR reflood phase following a large-break LOCA are quite unique in comparison with two-phase flow which has been studied widely in previous researches, because the geometry of the flow path is complicated (bundle geometry) and water is at extremely low superficial velocity and almost under stagnant condition. Hence, some phenomena realized during a PWR reflood phase are not understood enough and appropriate analytical models have not been developed, although they are important in a viewpoint of reactor safety evaluation. Therefore, author investigated some phenomena specified as important issues for quantitative prediction, i.e. (1) void fraction in a bundle during a PWR reflood phase, (2) effect of radial core power profile on reflood behavior, (3) effect of combined emergency core coolant injection on reflood behavior, and (4) the core separation into two thermal-hydraulically different regions and the in-core flow circulation behavior observed during a combined injection PWR reflood phase. Further, author made analytical models for these specified issues, and succeeded to predict reflood behaviors at representative types of PWRs, i.e.cold leg injection PWRs and Combined injection PWRs, in good accuracy. Above results were incorporated into REFLA code which is developed at JAERI, and they improved accuracy in prediction and enlarged applicability of the code. In the present study, models were intended to be utilized in a practical use, and hence these models are simplified ones. However, physical understanding on the specified issues in the present study is basic and principal for reflood behavior, and then it is considered to be used in a future advanced code development and improvement. (author). 110 refs.

  11. Hydraulic fracking sustainability assesment : case of study Luena (Cantabria, Spain)

    OpenAIRE

    Fernández Ferreras, Jose Antonio

    2014-01-01

    ABSTRACT: The opposition to Hydraulic fracturing in Cantabria, has led the Regional Government to enact a law that prohibits their use in the region, which has been suspended by the Central Government. The objective of this work is to Identify impacts on the environment, and the main economic and social factors (sustainability) in a case of study Luena research permit (with an estimated shale gas reserves of 10.34*109 Nm3), establishing a guide for assessing the activity of hydraulic fracturi...

  12. Strategic Need for Multi-Purpose Thermal Hydraulic Loop for Support of Advanced Reactor Technologies

    Energy Technology Data Exchange (ETDEWEB)

    James E. O' Brien; Piyush Sabharwall; Su-Jong Yoon; Gregory K. Housley

    2014-09-01

    This report presents a conceptual design for a new high-temperature multi fluid, multi loop test facility for the INL to support thermal hydraulic, materials, and thermal energy storage research for nuclear and nuclear-hybrid applications. In its initial configuration, the facility will include a high-temperature helium loop, a liquid salt loop, and a hot water/steam loop. The three loops will be thermally coupled through an intermediate heat exchanger (IHX) and a secondary heat exchanger (SHX). Research topics to be addressed with this facility include the characterization and performance evaluation of candidate compact heat exchangers such as printed circuit heat exchangers (PCHEs) at prototypical operating conditions, flow and heat transfer issues related to core thermal hydraulics in advanced helium-cooled and salt-cooled reactors, and evaluation of corrosion behavior of new cladding materials and accident-tolerant fuels for LWRs at prototypical conditions. Based on its relevance to advanced reactor systems, the new facility has been named the Advanced Reactor Technology Integral System Test (ARTIST) facility. Research performed in this facility will advance the state of the art and technology readiness level of high temperature intermediate heat exchangers (IHXs) for nuclear applications while establishing the INL as a center of excellence for the development and certification of this technology. The thermal energy storage capability will support research and demonstration activities related to process heat delivery for a variety of hybrid energy systems and grid stabilization strategies. Experimental results obtained from this research will assist in development of reliable predictive models for thermal hydraulic design and safety codes over the range of expected advanced reactor operating conditions. Proposed/existing IHX heat transfer and friction correlations and criteria will be assessed with information on materials compatibility and instrumentation

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

    International Nuclear Information System (INIS)

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

  14. Studies investigate effects of hydraulic fracturing

    Science.gov (United States)

    Balcerak, Ernie

    2012-11-01

    The use of hydraulic fracturing, also known as fracking, to enhance the retrieval of natural gas from shale has been increasing dramatically—the number of natural gas wells rose about 50% since 2000. Shale gas has been hailed as a relatively low-cost, abundant energy source that is cleaner than coal. However, fracking involves injecting large volumes of water, sand, and chemicals into deep shale gas reservoirs under high pressure to open fractures through which the gas can travel, and the process has generated much controversy. The popular press, advocacy organizations, and the documentary film Gasland by Josh Fox have helped bring this issue to a broad audience. Many have suggested that fracking has resulted in contaminated drinking water supplies, enhanced seismic activity, demands for large quantities of water that compete with other uses, and challenges in managing large volumes of resulting wastewater. As demand for expanded domestic energy production intensifies, there is potential for substantially increased use of fracking together with other recovery techniques for "unconventional gas resources," like extended horizontal drilling.

  15. Steady-state thermal-hydraulic design analysis of the Advanced Neutron Source reactor

    International Nuclear Information System (INIS)

    The Advanced Neutron Source (ANS) is a research reactor that is planned for construction at Oak Ridge National Laboratory. This reactor will be a user facility with the major objective of providing the highest continuous neutron beam intensities of any reactor in the world. Additional objectives for the facility include providing materials irradiation facilities and isotope production facilities as good as, or better than, those in the High Flux Isotope Reactor. To achieve these objectives, the reactor design uses highly subcooled heavy water as both coolant and moderator. Two separate core halves of 67.6-L total volume operate at an average power density of 4.5 MW(t)/L, and the coolant flows upward through the core at 25 m/s. Operating pressure is 3.1 MPa at the core inlet with a 1.4-MPa pressure drop through the core region. Finally, in order to make the resources available for experimentation, the fuel is designed to provide a 17-d fuel cycle with an additional 4 d planned in each cycle for the refueling process. This report examines the codes and models used to develop the thermal-hydraulic design for ANS, as well as the correlations and physical data; evaluates thermal-hydraulic uncertainties; reports on thermal-hydraulic design and safety analysis; describes experimentation in support of the ANS reactor design and safety analysis; and provides an overview of the experimental plan

  16. Selected thermal and hydraulic experimentation in support of the advanced neutron source reactor

    International Nuclear Information System (INIS)

    The ANS Reactor has unique thermal-hydraulic characteristics in comparison to other research and commercial reactors: Heavy water coolant, Parallel Rectangular channels (involute), Very small channel gap (1.27 mm), Very high velocity (25 m/s), Very high exit subcooling, Moderately high heat flux, High average power density. The objective was to determine experimentally the appropriate core thermal hydraulic limits at ANS conditions. Advanced Neutron Source (ANS) Thermal Hydraulic Test Loop (THTL) was designed to operate in 'Stiff', 'Soft' and 'Modified Stiff' Modes.Summary of Thermal Hydraulic Limit Testing and Analysis shows: FE data has been acquired at ANS typical flow velocities; An extensive OSV/OFI data base has been developed with a very broad parameter range, A modification of the Saha-Zuber correlation was proposed to account for reduced subcooling effects; Closeout activities include continued investigation of wider span test channels; Some testing for HFIR will be performed to evaluate the effect of reduced channel gap; Future plans called for additional testing at 3-core conditions, hot spot testing, etc. The Objective of Fuel Plate Stability Testing was to experimentally evaluate the structural response of ANS fuel plates to hydraulic loads. Summary of Fuel Plate Stability Testing shows: A Method Has Been Developed to Predict Structural Response of Fuel Plates to Hydraulic Loading Prediction of AP across plates Determine deflection/stress levels using structural analysis; ANS, Specific Conclusions are: no evidence of potential plate collapse in the coolant velocity range from 050 m/s, no evidence of plate flutter with coolant velocities below 33 m/s, local stress levels appear to dictate plate limits as opposed to plate deflection. The objective of Flow Blockage Testing was to experimentally determine local thermal and fluid. Summary of Flow Blockage Testing and Analysis showed: CFD code has been benchmarked against prototypic ANS flow conditions and

  17. Study of thermal - hydraulic sensors signal fluctuations in PWR

    International Nuclear Information System (INIS)

    This thesis deals with signal fluctuations of thermal-hydraulic sensors in the main coolant primary of a pressurized water reactor. The aim of this work is to give a first response about the potentiality of use of these noise signals for the functionning monitoring. Two aspects have been studied: - the modelisation of temperature fluctuations of core thermocouples, by a Monte-Carlo method, gives the main characteristics of these signals and their domain of application. - the determination of eigenfrequency in the primary by an acoustic representation could permit the monitoring of local and global thermo-hydraulic conditions

  18. Advanced thermal-hydraulic and neutronic codes: current and future applications. Summary and conclusions

    International Nuclear Information System (INIS)

    An OECD Workshop on Advanced Thermal-Hydraulic and Neutronic Codes Applications was held from 10 to 13 April 2000, in Barcelona, Spain, sponsored by the Committee on the Safety of Nuclear Installations (CSNI) of the OECD Nuclear Energy Agency (NEA). It was organised in collaboration with the Spanish Nuclear Safety Council (CSN) and hosted by CSN and the Polytechnic University of Catalonia (UPC) in collaboration with the Spanish Electricity Association (UNESA). The objectives of the Workshop were to review the developments since the previous CSNI Workshop held in Annapolis [NEA/CSNI/ R(97)4; NUREG/CP-0159], to analyse the present status of maturity and remnant needs of thermal-hydraulic (TH) and neutronic system codes and methods, and finally to evaluate the role of these tools in the evolving regulatory environment. The Technical Sessions and Discussion Sessions covered the following topics: - Regulatory requirements for Best-Estimate (BE) code assessment; - Application of TH and neutronic codes for current safety issues; - Uncertainty analysis; - Needs for integral plant transient and accident analysis; - Simulators and fast running codes; - Advances in next generation TH and neutronic codes; - Future trends in physical modeling; - Long term plans for development of advanced codes. The focus of the Workshop was on system codes. An incursion was made, however, in the new field of applying Computational Fluid Dynamic (CFD) codes to nuclear safety analysis. As a general conclusion, the Barcelona Workshop can be considered representative of the progress towards the targets marked at Annapolis almost four years ago. The Annapolis Workshop had identified areas where further development and specific improvements were needed, among them: multi-field models, transport of interfacial area, 2D and 3D thermal-hydraulics, 3-D neutronics consistent with level of details of thermal-hydraulics. Recommendations issued at Annapolis included: developing small pilot/test codes for

  19. Proceedings of the workshop on advanced thermal-hydraulic and neutronic codes: current and future applications

    International Nuclear Information System (INIS)

    An OECD Workshop on Advanced Thermal-Hydraulic and Neutronic Codes Applications was held from 10 to 13 April 2000, in Barcelona, Spain, sponsored by the Committee on the Safety of Nuclear Installations (CSNI) of the OECD Nuclear Energy Agency (NEA). It was organised in collaboration with the Spanish Nuclear Safety Council (CSN) and hosted by CSN and the Polytechnic University of Catalonia (UPC) in collaboration with the Spanish Electricity Association (UNESA). The objectives of the Workshop were to review the developments since the previous CSNI Workshop held in Annapolis [NEA/CSNI/ R(97)4; NUREG/CP-0159], to analyse the present status of maturity and remnant needs of thermal-hydraulic (TH) and neutronic system codes and methods, and finally to evaluate the role of these tools in the evolving regulatory environment. The Technical Sessions and Discussion Sessions covered the following topics: - Regulatory requirements for Best-Estimate (BE) code assessment; - Application of TH and neutronic codes for current safety issues; - Uncertainty analysis; - Needs for integral plant transient and accident analysis; - Simulators and fast running codes; - Advances in next generation TH and neutronic codes; - Future trends in physical modeling; - Long term plans for development of advanced codes. The focus of the Workshop was on system codes. An incursion was made, however, in the new field of applying Computational Fluid Dynamic (CFD) codes to nuclear safety analysis. As a general conclusion, the Barcelona Workshop can be considered representative of the progress towards the targets marked at Annapolis almost four years ago. The Annapolis Workshop had identified areas where further development and specific improvements were needed, among them: multi-field models, transport of interfacial area, 2D and 3D thermal-hydraulics, 3-D neutronics consistent with level of details of thermal-hydraulics. Recommendations issued at Annapolis included: developing small pilot/test codes for

  20. Update to advanced neutron source steady-state thermal-hydraulic report

    International Nuclear Information System (INIS)

    This report is intended to be a supplement to ORNL/TM-12398, Steady-State Thermal-Hydraulic Design Analysis of the Advanced Neutron Source Reactor. It updates the core thermal-hydrualic design to the latest three-element configuration and also provides the most recent information on the thermal-hydraulic statistical uncertainty analysis. In addition, it includes calculations of beam tube cooling and control rod lift forces, which were not addressed in the initial report. This report describes work that is a snapshot in time as it stood at the end of the project. The three-element core calculations include a description of changes made to the overall coolant system; however, most of the analysis is focused on fuel loading thermal-hydraulic calculations. This analysis uses updated uncertainty values and indicates that a two-dimensional fuel grading in the three-element core would still be necessary to meet the desired operating and safety criteria. Analysis of cooling in the reflector tank examines various cooling options for the reflector tank components. This work investigated multiple forced convection designs as well as natural convection cooling requirements. Lift forces on the inner control rods caused by the upward coolant flow were also examined. Initial control rod designs were such that a sheared control rod would tend to lift because of flow forces. Design changes were recommended that would eliminate this issue. They included geometry changes to the inner control rod cooling channels, changes to the orificing in the central hole region, and reduction of inner control rod coolant velocity

  1. The hydraulic bulge tester in fracture studies

    International Nuclear Information System (INIS)

    The theory and practice of hydrostatic bulge testing of thin diaphragms is reviewed. Circular, elliptical and rectangular orifices are considered in terms of pressure vs height of dome plots, strain-distributions etc. Differences in modes of failure (location of necks, existence or not of pressure peaks) between circular and rectangular diaphragms are highlighted both for metals and polymers. The use of the bulger to construct forming limit diagrams (FLD) and fracture forming limit diagrams (FFLD) is described. How bulging is used for both fracture initiating and propagation studies is indicated, particularly as it may relate to the prospect for results from a 'giant' bulger of 1 m diameter orifice to be used for investigating thick plate. (author)

  2. Tap Water Hydraulic Control Systems - Design and Industrial Applications. Chapter 7 in Advances in Hydraulic Control Systems

    DEFF Research Database (Denmark)

    Conrad, Finn

    Deals with development and design of modern tap water hydraulic components and systems, in particalar the Danfoss Nessie-family of components and systems working with pure tap water without any kind of additives. Typical industrial applications are presented and the perspectives of new industrial...... applications and the environmental benefits are in focus, in particular in the food processing industry and in fire-fighting systems....

  3. Experimental Study on Hydraulic Rotation Device for Neutron Transmutation Doping

    International Nuclear Information System (INIS)

    The conceptual design of the hydraulic-driven rotation system and experimental apparatus was proposed to make up for the weakness of the former motor-driven rotation system which is needed to enhance the reliability of an NTD system. Through the proposed design, the potential for application to a new NTD rotation system will be verified. It is necessary to conduct a further study to establish this new method completely. As the commercial needs for NTD in a research reactor are increasing, all research reactors constructed recently or under the design stage have an NTD irradiation facility. For uniform irradiation, the most important factor for the production of NTD-silicon, it is necessary to rotate the silicon ingot at a uniform speed at a certain position in the NTD irradiation holes. In this study, a new NTD hydraulic rotation device to rotate the silicon ingot with a uniform speed was developed for the purpose of application to the KJRR research reactor

  4. Study on an Axial Flow Hydraulic Turbine with Collection Device

    OpenAIRE

    Yasuyuki Nishi; Terumi Inagaki; Kaoru Okubo; Norio Kikuchi

    2014-01-01

    We propose a new type of portable hydraulic turbine that uses the kinetic energy of flow in open channels. The turbine comprises a runner with an appended collection device that includes a diffuser section in an attempt to improve the output by catching and accelerating the flow. With such turbines, the performance of the collection device, and a composite body comprising the runner and collection device were studied using numerical analysis. Among four stand-alone collection devices, the inl...

  5. 75 FR 35023 - Informational Public Meetings for Hydraulic Fracturing Research Study

    Science.gov (United States)

    2010-06-21

    ... AGENCY Informational Public Meetings for Hydraulic Fracturing Research Study AGENCY: Environmental... between hydraulic fracturing and drinking water. The meetings are open to all interested parties and will... Hydraulic Fracturing Study informational meetings are as follows: July 8, 2010, from 6 p.m. to 10 p.m.,...

  6. Hydraulic Shuttle Irradiation System (HSIS) Recently Installed in the Advanced Test Reactor (ATR)

    International Nuclear Information System (INIS)

    Most test reactors are equipped with shuttle facilities (sometimes called rabbit tubes) whereby small capsules can be inserted into the reactor and retrieved during power operations. With the installation of Hydraulic Shuttle Irradiation System (HSIS) this capability has been restored to the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). The general design and operating principles of this system were patterned after the hydraulic rabbit at Oak Ridge National Laboratory's (ORNL) High Flux Isotope Reactor (HFIR), which has operated successfully for many years. Using primary coolant as the motive medium the HSIS system is designed to simultaneously transport fourteen shuttle capsules, each 16 mm OD x 57 mm long, to and from the B-7 position of the reactor. The B-7 position is one of the higher flux positions in the reactor with typical thermal and fast (>1 Mev) fluxes of 2.8E+14 n/cm2/sec and 1.9E+14 n/cm2/sec respectively. The available space inside each shuttle is approximately 14 mm diameter x 50 mm long. The shuttle containers are made from titanium which was selected for its low neutron activation properties and durability. Shuttles can be irradiated for time periods ranging from a few minutes to several months. The Send and Receive Station (SRS) for the HSIS is located 2.5 m deep in the ATR canal which allows irradiated shuttles to be easily moved from the SRS to a wet loaded cask, or transport pig. The HSIS system first irradiated (empty) shuttles in September 2009 and has since completed a Readiness Assessment in November 2009. The HSIS is a key component of the ATR National Scientific User Facility (NSUF) operated by Battelle Energy Alliance, LLC and is available to a wide variety of university researchers for nuclear fuels and materials experiments as well as medical isotope research and production.

  7. Fusion advanced studies Torus

    International Nuclear Information System (INIS)

    The successful development of ITER and DEMO scenarios requires preparatory activities on devices that are smaller than ITER, sufficiently flexible and capable of investigating the peculiar physics of burning plasma conditions. The aim of the Fusion Advanced Studies Torus (FAST) proposal [2.1] (formerly FT3 [2.2]) is to show that the preparation of ITER scenarios and the development of new expertise for the DEMO design and RD can be effectively implemented on a new facility. FAST will a) operate with deuterium plasmas, thereby avoiding problems associated with tritium, and allow investigation of nonlinear dynamics (which are important for understanding alpha particle behaviour in burning plasmas) by using fast ions accelerated by heating and current drive systems; b) work in a dimensionless parameter range close to that of ITER; c) test technical innovative solutions, such as full-tungsten plasma-facing components and an advanced liquid metal divertor target for the first wall/divertor, directly relevant for ITER and DEMO; d) exploit advanced regimes with a much longer pulse duration than the current diffusion time; e) provide a test bed for ITER and DEMO diagnostics; f) provide an ideal framework for model and numerical code benchmarks, their verification and validation in ITER/ DEMO-relevant plasma conditions

  8. HYDRAULIC STUDIES AND CLEANING EVALUATIONS OF ULTRAVIOLET DISINFECTION UNITS

    Science.gov (United States)

    Various types of operating ultraviolet disinfection reactor designs were evaluated for hydraulic characteristics and cleaning requirements. The fluorocarbon polymer tube designs promote plug-flow behavior because of their relatively high length-to-diameter ratio. Hydraulic evalua...

  9. An experimental study of hydraulic fracture and erosion

    OpenAIRE

    Mhach, H.K.

    1991-01-01

    This thesis concerns an experimental investigation of hydraulic fracturing when the water pressure is increased rapidly in a borehole and development of a possible simple method for identifying erodible clayey soils. Case histories of hydraulic fracturing in embankment dams and boreholes are reviewed. It is found that hydraulic fracturing in dams is often associated with rapid reservoir filling and zones of low stresses. Previously proposed criteria for hydraulic fracturing are outlined. It i...

  10. Study on Knowledge -based Intelligent Fault Diagnosis of Hydraulic System

    Directory of Open Access Journals (Sweden)

    Xuexia Liu

    2012-12-01

    Full Text Available A general framework of hydraulic fault diagnosis system was studied. It consisted of equipment knowledge bases, real-time databases, fusion reasoning module, knowledge acquisition module and so on. A tree-structure model of fault knowledge was established. Fault nodes knowledge was encapsulated by object-oriented technique. Complete knowledge bases were made including fault bases and diagnosis bases. It could describe the fault positions, the structure of fault, cause-symptom relationships, diagnosis principles and other knowledge. Taking the fault of left and right lifting oil cylinder out of sync for example, the diagnostic results show that the methods were effective.

  11. Hydraulic Fracturing and Drinking Water Resources: Update on EPA Hydraulic Fracturing Study

    Science.gov (United States)

    Natural gas plays a key role in our nation's energy future and the process known as hydraulic fracturing (HF) is one way of accessing that resource. Over the past few years, several key technical, economic, and energy developments have spurred increased use of HF for gas extracti...

  12. A review of modern advances in analyses and applications of single-phase natural circulation loop in nuclear thermal hydraulics

    International Nuclear Information System (INIS)

    Highlights: • Comprehensive review of state-of-the-art on single-phase natural circulation loops. • Detailed discussion on growth in solar thermal system and nuclear thermal hydraulics. • Systematic development in scaling methodologies for fabrication of test facilities. • Importance of numerical modeling schemes for stability assessment using 1-D codes. • Appraisal of current trend of research and possible future directions. - Abstract: A comprehensive review of single-phase natural circulation loop (NCL) is presented here. Relevant literature reported since the later part of 1980s has been meticulously surveyed, with occasional obligatory reference to a few pioneering studies originating prior to that period, summarizing the key observations and the present trend of research. Development in the concept of buoyancy-induced flow is discussed, with introduction to flow initiation in an NCL due to instability. Detailed discussion on modern advancement in important application areas like solar thermal systems and nuclear thermal hydraulics are presented, with separate analysis for various reactor designs working on natural circulation. Identification of scaling criteria for designing lab-scale experimental facilities has gone through a series of modification. A systematic analysis of the same is presented, considering the state-of-the-art knowledge base. Different approaches have been followed for modeling single-phase NCLs, including simplified Lorenz system mostly for toroidal loops, 1-D computational modeling for both steady-state and stability characterization and 3-D commercial system codes to have a better flow visualization. Methodical review of the relevant studies is presented following a systematic approach, to assess the gradual progression in understanding of the practical system. Brief appraisal of current research interest is reported, including the use of nanofluids for fluid property augmentation, marine reactors subjected to rolling waves

  13. Thermal hydraulic test apparatus to develop advanced BWR fuel bundles with spectral shift rods (SSR)

    International Nuclear Information System (INIS)

    An advanced water rod (WR) called the spectral shift rod (SSR), which replaces a conventional WR in a BWR fuel bundle, enhances the BWR's merit of uranium saving through the spectral shift operation. The SSR consists of an inlet hole, a wide ascending path, a narrow descending path and an outlet hole. The inlet hole locates below a lower tie plate (LTP) and the outlet hole is set above it. In the SSR, water boils by neutron and gamma-ray heating and water level is formed in the ascending path. This SSR water level can be controlled by core flow rate, which amplifies core void fraction change, resulting in the amplified spectral shift effect. Steady state and transient tests were conducted to evaluate SSR thermal-hydraulic characteristics under BWR operation condition. The several types of SSR configuration were tested, which covers SSR design in both next generation and conventional BWRs. In this paper, the test apparatus overview and measurement systems especially two phase water level measures in the SSR are presented. (author)

  14. Korean development of advanced thermal-hydraulic codes for water reactors and HTGRS: space and gamma

    International Nuclear Information System (INIS)

    Korea has been developing SPACE(Safety and Performance Analysis CodE) and GAMMA(GAs Multicomponent Mixture Analysis) codes for safety analysis of PWRs and HTGRs, respectively. SPACE is being developed by the Korea nuclear industry, which is a thermal-hydraulic analysis code for safety analysis of a PWR. It will replace outdated vendor supplied codes and will be used for the safety analysis of operating PWR and the design of an advanced PWR. It consists of the up-to-date physical models of two-phase flow dealing with multi-dimensional two-fluid, three-field flow. The GAMMA code consists of the multi-dimensional governing equations consisting of the basic equations for continuity, momentum conservation, energy conservation of the gas mixture, and mass conservation of n species. GAMMA is based on a porous media model so that we can deal with the thermo-fluid and chemical reaction behaviors in a multicomponent mixture system as well as heat transfer within the solid components, free and forced convection between a solid and a fluid, and radiative heat transfer between the solid surfaces. GAMMA has a model for helium turbines for HTGRs based on the throughflow calculation. We performed extensive code assessment for the V&V of SPACE and GAMMA. (author)

  15. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Evren Ozbayoglu; Lei Zhou

    2002-04-30

    This is the third quarterly progress report for Year 3 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between Jan. 1, 2002 and Mar. 31, 2002. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 3: Addition of a Cuttings Injection/Separation System), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 9b): ''Study of Foam Flow Behavior Under EPET Conditions'', (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b); (f) Development of a Safety program for the ACTS Flow Loop, progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S); and (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  16. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Affonso Lourenco; Evren Ozbayoglu; Lei Zhou

    2002-01-30

    This is the second quarterly progress report for Year 3 of the ACTS project. It includes a review of progress made in: (1) Flow Loop development and (2) research tasks during the period of time between Oct 1, 2001 and Dec. 31, 2001. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 3: Addition of a Cuttings Injection/Collection System), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (e) Research on instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), and Foam properties while transporting cuttings. (Task 12), (f) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  17. Development of Design Technology on Thermal-Hydraulic Performance in Tight-Lattice Rod Bundles: III - Numerical Evaluation of Fluid Mixing Phenomena using Advanced Interface-Tracking Method -

    Science.gov (United States)

    Yoshida, Hiroyuki; Nagayoshi, Takuji; Takase, Kazuyuki; Akimoto, Hajime

    Thermal-hydraulic design of the current boiling water reactor (BWR) is performed by correlations with empirical results of actual-size tests. However, for the Innovative Water Reactor for Flexible Fuel Cycle (FLWR) core, an actual size test of an embodiment of its design is required to confirm or modify such correlations. Development of a method that enables the thermal-hydraulic design of nuclear reactors without these actual size tests is desired, because these tests take a long time and entail great cost. For this reason we developed an advanced thermal-hydraulic design method for FLWRs using innovative two-phase flow simulation technology. In this study, detailed Two-Phase Flow simulation code using advanced Interface Tracking method: TPFIT is developed to calculate the detailed information of the two-phase flow. We tried to verify the TPFIT code by comparing it with the 2-channel air-water and steam-water mixing experimental results. The predicted result agrees well the observed results and bubble dynamics through the gap and cross flow behavior could be effectively predicted by the TPFIT code, and pressure difference between fluid channels is responsible for the fluid mixing.

  18. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira; Lei Zhou

    2000-01-30

    This is the second quarterly progress report for Year 2 of the ACTS project. It includes a review of progress made in Flow Loop development and research during the period of time between Oct 1, 2000 and December 31, 2000. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 2: Addition of a foam generation and breaker system), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 7): ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (d) Research project (Task 8): ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (e) Research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (g) Research on instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), and Foam properties while transporting cuttings. (Task 12), (h) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (i) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members. The tasks Completed During This Quarter are Task 7 and Task 8.

  19. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira

    2000-10-30

    This is the first quarterly progress report for Year 2 of the ACTS project. It includes a review of progress made in Flow Loop development and research during the period of time between July 14, 2000 and September 30, 2000. This report presents information on the following specific tasks: (a) Progress in Advanced Cuttings Transport Facility design and development (Task 2), (b) Progress on research project (Task 8): ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (c) Progress on research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (d) Progress on research project (Task 7): ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (e) Progress on research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Initiate research on project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (g) Progress on instrumentation tasks to measure: Cuttings concentration and distribution (Tasks 11), and Foam properties (Task 12), (h) Initiate a comprehensive safety review of all flow-loop components and operational procedures. Since the previous Task 1 has been completed, we will now designate this new task as: (Task 1S). (i) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  20. Thermal-hydraulics analysis for advanced fuel to be used in Candu 600 nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Catana, Alexandru [RAAN, Institute for Nuclear Research, Str. Campului Nr. 1, Pitesti, Arges (Romania); Danila, Nicolae; Prisecaru, Ilie; Dupleac, Daniel [University POLITEHNICA of Bucharest (Romania)

    2008-07-01

    Two Candu 600 pressure tube nuclear reactors cover about 17% of Romania's electricity demand. These nuclear reactors are moderated/cooled with D{sub 2}O, fuelled on-power with Natural Uranium (NU) dioxide encapsulated in a standard (STD37) fuel bundle. High neutron economy is achieved using D{sub 2}O as moderator and coolant in separated systems. To reduce fuel cycle costs, programs were initiated in Canada, S.Korea, Argentina and Romania for the design and build new fuel bundles able to accommodate different fuel compositions. Candu core structure and modular fuel bundles, permits flexible fuel cycles. The main expected achievements are: reduced fuel cycle costs, increased discharge burn-up, plutonium and minor actinides management, thorium cycle, use of recycled PWR and in the same time waste minimization and operating cost reduction. These new fuel bundles are to be used in already operated Candu reactors. Advanced fuel bundle were proposed: CANFLEX bundle (Canada, S-Korea); the Romanian 'SEU43' bundle (Fig 1). In this paper thermal-hydraulic analysis in sub-channel approach is presented for SEU43. Comparisons with standard (STD37) fuel bundles are made using SEU-NU for NU fuel composition and SEU-0.96, for recycled uranium (RU) fuel with 0.96% U-235. Extended and comprehensive analysis must be made in order to assess the TH behaviour of SEU43. In this paper, considering STD37, SEU43-NU and SEU43-0.96 fuel bundles, main TH parameters were analysed: pressure drop, fuel highest temperatures, coolant density, critical heat flux. Differences between these fuel types are outlined. Benefits are: fuel costs reduction, spent fuel waste minimization, increase in competitiveness of nuclear power. Safety margins must be, at least, conserved. (authors)

  1. Triaxial coreflood study of the hydraulic fracturing of Utica Shale

    Science.gov (United States)

    Carey, J. W.; Frash, L.; Viswanathan, H. S.

    2015-12-01

    One of the central questions in unconventional oil and gas production research is the cause of limited recovery of hydrocarbon. There are many hypotheses including: 1) inadequate penetration of fractures within the stimulated volume; 2) limited proppant delivery; 3) multiphase flow phenomena that blocks hydrocarbon migration; etc. Underlying any solution to this problem must be an understanding of the hydrologic properties of hydraulically fractured shale. In this study, we conduct triaxial coreflood experiments using a gasket sealing mechanism to characterize hydraulic fracture development and permeability of Utica Shale samples. Our approach also includes fracture propagation with proppants. The triaxial coreflood experiments were conducted with an integrated x-ray tomography system that allows direct observation of fracture development using x-ray video radiography and x-ray computed tomography at elevated pressure. A semi-circular, fracture initiation notch was cut into an end-face of the cylindrical samples (1"-diameter with lengths from 0.375 to 1"). The notch was aligned parallel with the x-ray beam to allow video radiography of fracture growth as a function of injection pressure. The proppants included tungsten powder that provided good x-ray contrast for tracing proppant delivery and distribution within the fracture system. Fractures were propagated at injection pressures in excess of the confining pressure and permeability measurements were made in samples where the fractures propagated through the length of the sample, ideally without penetrating the sample sides. Following fracture development, permeability was characterized as a function of hydrostatic pressure and injection pressure. X-ray video radioadiography was used to study changes in fracture aperture in relation to permeability and proppant embedment. X-ray tomography was collected at steady-state conditions to fully characterize fracture geometry and proppant distribution.

  2. Sensitivity study on hydraulic well testing inversion using simulated annealing

    International Nuclear Information System (INIS)

    For environmental remediation, management of nuclear waste disposal, or geothermal reservoir engineering, it is very important to evaluate the permeabilities, spacing, and sizes of the subsurface fractures which control ground water flow. Cluster variable aperture (CVA) simulated annealing has been used as an inversion technique to construct fluid flow models of fractured formations based on transient pressure data from hydraulic tests. A two-dimensional fracture network system is represented as a filled regular lattice of fracture elements. The algorithm iteratively changes an aperture of cluster of fracture elements, which are chosen randomly from a list of discrete apertures, to improve the match to observed pressure transients. The size of the clusters is held constant throughout the iterations. Sensitivity studies using simple fracture models with eight wells show that, in general, it is necessary to conduct interference tests using at least three different wells as pumping well in order to reconstruct the fracture network with a transmissivity contrast of one order of magnitude, particularly when the cluster size is not known a priori. Because hydraulic inversion is inherently non-unique, it is important to utilize additional information. The authors investigated the relationship between the scale of heterogeneity and the optimum cluster size (and its shape) to enhance the reliability and convergence of the inversion. It appears that the cluster size corresponding to about 20--40 % of the practical range of the spatial correlation is optimal. Inversion results of the Raymond test site data are also presented and the practical range of spatial correlation is evaluated to be about 5--10 m from the optimal cluster size in the inversion

  3. Study of the Process of Hydraulic Mixing in Anaerobic Digester of Biogas Plant

    Directory of Open Access Journals (Sweden)

    Karaeva Julia V.

    2015-03-01

    Full Text Available Two systems of hydraulic mixing in a vertical cylindrical anaerobic digester: standard and modernised are discussed in the paper. Numerical investigations that were carried out are focused on a study of hydrodynamic processes in an aerobic digester using two various systems of hydraulic mixing as well as on analysis of the efficiency of methane fermentation process accomplished under different geometric parameters of an anaerobic digester and systems of hydraulic mixing.

  4. The dynamic running law study on driving system of hydraulic winder

    Institute of Scientific and Technical Information of China (English)

    彭佑多; 刘德顺; 郭迎福; 张永忠; 文西芹

    2002-01-01

    Dynamic running law of the hydraulic driving system decides the hoisting cage velocity curve in a hoisting cycle and is decided by the characteristic of the hydraulic driving system and by the operating speed of hoist driver. The paper studies the dynamic running law of hydraulic driving system, analyses the influence of driver operating speed on the dynamic running characteristic, and points out the reasonable driver operating speed to control the dynamic stress in rope and to reduce the oscillation of rope system.

  5. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Ergun Kuru; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira; Neelima Godugu

    2000-07-30

    ACTS flow loop is now operational under elevated pressure and temperature. Currently, experiments with synthetic based drilling fluids under pressure and temperature are being conducted. Based on the analysis of Fann 70 data, empirical correlations defining the shear stress as a function of temperature, pressure and the shear rate have been developed for Petrobras synthetic drilling fluids. PVT equipment has been modified for testing Synthetic oil base drilling fluids. PVT tests with Petrobras Synthetic base mud have been conducted and results are being analyzed Foam flow experiments have been conducted and the analysis of the data has been carried out to characterize the rheology of the foam. Comparison of pressure loss prediction from the available foam hydraulic models and the test results has been made. Cuttings transport experiments in horizontal annulus section have been conducted using air, water and cuttings. Currently, cuttings transport tests in inclined test section are being conducted. Foam PVT analysis tests have been conducted. Foam stability experiments have also been conducted. Effects of salt and oil concentration on the foam stability have been investigated. Design of ACTS flow loop modification for foam and aerated mud flow has been completed. A flow loop operation procedure for conducting foam flow experiments under EPET conditions has been prepared Design of the lab-scale flow loop for dynamic foam characterization and cuttings monitoring instrumentation tests has been completed. The construction of the test loop is underway. As part of the technology transport efforts, Advisory Board Meeting with ACTS-JIP industry members has been organized on May 13, 2000.

  6. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mengjiao Yu; Ramadan Ahmed; Mark Pickell; Len Volk; Lei Zhou; Zhu Chen; Aimee Washington; Crystal Redden

    2003-09-30

    The Quarter began with installing the new drill pipe, hooking up the new hydraulic power unit, completing the pipe rotation system (Task 4 has been completed), and making the SWACO choke operational. Detailed design and procurement work is proceeding on a system to elevate the drill-string section. The prototype Foam Generator Cell has been completed by Temco and delivered. Work is currently underway to calibrate the system. Literature review and preliminary model development for cuttings transportation with polymer foam under EPET conditions are in progress. Preparations for preliminary cuttings transport experiments with polymer foam have been completed. Two nuclear densitometers were re-calibrated. Drill pipe rotation system was tested up to 250 RPM. Water flow tests were conducted while rotating the drill pipe up to 100 RPM. The accuracy of weight measurements for cuttings in the annulus was evaluated. Additional modifications of the cuttings collection system are being considered in order to obtain the desired accurate measurement of cuttings weight in the annular test section. Cutting transport experiments with aerated fluids are being conducted at EPET, and analyses of the collected data are in progress. The printed circuit board is functioning with acceptable noise level to measure cuttings concentration at static condition using ultrasonic method. We were able to conduct several tests using a standard low pass filter to eliminate high frequency noise. We tested to verify that we can distinguish between different depths of sand in a static bed of sand. We tested with water, air and a mix of the two mediums. Major modifications to the DTF have almost been completed. A stop-flow cell is being designed for the DTF, the ACTF and Foam Generator/Viscometer which will allow us to capture bubble images without the need for ultra fast shutter speeds or microsecond flash system.

  7. AREVA NP's advanced Thermal Hydraulic Methods for Reactor Core and Fuel Assembly Design

    International Nuclear Information System (INIS)

    The main objective of the Thermal Hydraulic (TH) analysis of reactor core and fuel assembly design is the determination of pressure loss and critical heat flux (CHF). Especially the description of the latter effect requires the modeling of a large variety of physical phenomena starting with single phase quantities like turbulence or fluid-wall friction, two phase quantities like void distributions, heat transfer between fuel rod and fluid and ultimately the CHF mechanism itself. Additional complexity is added by the fact that the relevant geometric scales which have to be resolved, cover a wide range from the length of the fuel assembly (∼ 4000 mm), over the typical dimensions of sub-channel cross sections and the vanes on the spacer grids (∼ 10 mm) down to the microscopic scales set by bubble sizes and boundary layers (mm to sub mm). Due to the above described situation the necessary TH quantities are often determined by measurements. The main advantage of this technique is that measurements are widely accepted and trusted if the geometry and flow conditions are sufficiently close to real reactor conditions. The main disadvantage of experiments is that they are expensive both with respect to time and money; especially in high pressure tests they give only limited access to the test object. Consequently there is a strong interest to develop computer codes with the goal of minimizing the need of experiments, and hence, speeding up and reducing costs of fuel assembly and core design. Today most of the design work is based on sub-channel codes, originally developed in the 70's; they provide an effective description of the TH in fuel assemblies by regarding the fuel assembly as a system of communicating channels (the volume enclosed by four fuel rods = one sub-channel). Further development of these codes is one main focus of AREVA NP's Thermal Hydraulic method and code development strategy. To focus the know-how and resources existing in the different regions of

  8. 75 FR 36387 - Informational Public Meetings for Hydraulic Fracturing Research Study; Correction

    Science.gov (United States)

    2010-06-25

    ..., 2010, in FR doc. 2010-14897, on page 35023, in the third Column, correct the Web site addresses shown... AGENCY Informational Public Meetings for Hydraulic Fracturing Research Study; Correction AGENCY... Hydraulic Fracturing Research Study. The document contained an incorrect EPA Web site address in two...

  9. Final Plan to Study the Potential Impacts of Hydraulic Fracturing on Drinking Water Resources

    Science.gov (United States)

    The overall purpose of this study is to elucidate the relationship, if any, between hydraulic fracturing and drinking water resources. More specifically, the study has been designed to assess the potential impacts of hydraulic fracturing on drinking water resources and to identif...

  10. Study on the thermal-hydraulic stability of high burn up STEP III fuel in Japan

    International Nuclear Information System (INIS)

    Japanese BWR utilities have performed a joint study of the Thermal Hydraulic Stability of High Burn up STEP III Fuel. In this study, the parametric dependency of thermal hydraulic stability threshold was obtained. It was confirmed through experiments that the STEP III Fuel has sufficient stability characteristics. (author)

  11. FLICA-OVAP: Elements of validation for LWRs thermal-hydraulic studies

    International Nuclear Information System (INIS)

    FLICA-OVAP is an advanced two-phase flow thermal-hydraulics code based on a full 3-Dimensional subchannel approach. It is designed to analyze flows in Light Water Reactors (LWRs) cores such as PWRs, BWRs and experimental reactors. Therefore its applicability covers all ranges of operating conditions for water-cooled reactors. The FLICA-OVAP code includes several models, to adapt to the needs associated to different core concepts and multiple industrial and research applications. The set of models includes a Homogeneous Equilibrium Model (HEM), a four-equation drift flux model, a two-fluid model and a more general multi-field model. Several correlations are available to account for momentum, heat and mass transfer phenomena, as well as turbulence effects. This paper presents an overview of FLICA-OVAP modelling capabilities for applications in nuclear reactors design and safety analysis. A validation matrix is proposed and its results are presented. The matrix covers a wide range of selected phenomena, which are relevant for thermal-hydraulics studies. Therefore the different FLICA-OVAP physical correlations addressed in the current study include single phase and two-phase friction factors, single phase and boiling heat transfer, turbulence and critical heat flux. Results of the FLICA-OVAP validation studies highlight the capabilities of the code to well-predict two-phase flows in Light Water Reactors for both normal operation and under accidental circumstances. Future developments as well as validation activities are also summarized. (authors)

  12. Preliminary research on RTDP methodology for advanced LPP thermal-hydraulic design

    International Nuclear Information System (INIS)

    Departure from nucleate boiling (DNB) design basis is one of the most important basis for reactor core thermal-hydraulic design. In order to evaluate whether the DNB design basis meets the demand of thermal-hydraulic design, the departure from nucleate boiling ratio (DNBR) design limit should be determined first. The RTDP methodology was described detailedly, in which the uncertainties of operating parameters and nuclear design parameters were statistically combined. Then the RTDP methodology and a reactor subchannel code were applied to calculate the DNBR design limit and quality limit for LPP. The conclusions were presented to provide the key acceptable criterion for DNBR design basis. (authors)

  13. Experimental Study on Abrasive Waterjet Polishing of Hydraulic Turbine Blades

    International Nuclear Information System (INIS)

    In this paper, an experimental investigation is implemented on the abrasive waterjet polishing technique to evaluate its capability in polishing of surfaces and edges of hydraulic turbine blades. For this, the properties of this method are studied and the main parameters affecting its performance are determined. Then, an experimental test-rig is designed, manufactured and tested to be used in this study. This test-rig can be used to polish linear and planar areas on the surface of the desired workpieces. Considering the number of parameters and their levels, the Taguchi method is used to design the preliminary experiments. All experiments are then implemented according to the Taguchi L18 orthogonal array. The signal-to-noise ratios obtained from the results of these experiments are used to determine the importance of the controlled polishing parameters on the final quality of the polished surface. The evaluations on these ratios reveal that the nozzle angle and the nozzle diameter have the most important impact on the results. The outcomes of these experiments can be used as a basis to design a more precise set of experiments in which the optimal values of each parameter can be estimated

  14. Plan to Study the Potential Impacts of Hydraulic Fracturing on Drinking Water Resources (Monterey, CA)

    Science.gov (United States)

    A summary of EPA's research relating to potential impacts of hydraulic fracturing on drinking water resources will be presented. Background about the study plan development will be presented along with an analysis of the water cycle as it relates to hydraulic fracturing processe...

  15. Experimental studies of rock fracture behavior related to hydraulic fracture

    Science.gov (United States)

    Ma, Zifeng

    The objective of this experimental investigation stems from the uncontrollable of the hydraulic fracture shape in the oil and gas production field. A small-scale laboratory investigation of crack propagation in sandstone was first performed with the objective to simulate the field fracture growth. Test results showed that the fracture resistance increased with crack extension, assuming that there was an interaction between crack faces (bridging, interlocking, and friction). An acoustic emission test was conducted to examine the existence of the interaction by locating AE events and analyzing waveform. Furthermore, the effects of confining stress, loading rate, stress field, and strength heterogeneous on the tortuosity of the fracture surface were experimentally investigated in the study. Finally, a test was designed and conducted to investigate the crack propagation in a stratified media with permeability contrast. Crack was observed to arrested in an interface. The phenomenon of delamination along an interface between layers with permeability contrast was observed. The delamination was proposed to be the cause of crack arrest and crack jump in the saturated stratified materials under confinement test.

  16. Study on an Axial Flow Hydraulic Turbine with Collection Device

    Directory of Open Access Journals (Sweden)

    Yasuyuki Nishi

    2014-01-01

    Full Text Available We propose a new type of portable hydraulic turbine that uses the kinetic energy of flow in open channels. The turbine comprises a runner with an appended collection device that includes a diffuser section in an attempt to improve the output by catching and accelerating the flow. With such turbines, the performance of the collection device, and a composite body comprising the runner and collection device were studied using numerical analysis. Among four stand-alone collection devices, the inlet velocity ratio was most improved by the collection device featuring an inlet nozzle and brim. The inlet velocity ratio of the composite body was significantly lower than that of the stand-alone collection device, owing to the resistance of the runner itself, the decreased diffuser pressure recovery coefficient, and the increased backpressure coefficient. However, at the maximum output tip speed ratio, the inlet velocity ratio and the loading coefficient were approximately 31% and 22% higher, respectively, for the composite body than for the isolated runner. In particular, the input power coefficient significantly increased (by approximately 2.76 times owing to the increase in the inlet velocity ratio. Verification tests were also conducted in a real canal to establish the actual effectiveness of the turbine.

  17. Thermal Hydraulic design parameters study for severe accidents using neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Chang Hyun; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of); Chang, Keun Sun [Sunmoon University, Asan (Korea, Republic of)

    1997-12-31

    To provide the information on severe accident progression is very important for advanced or new type of nuclear power plant (NPP) design. A parametric study, therefore, was performed to investigate the effect of thermal hydraulic design parameters on severe accident progression of pressurized water reactors (PWRs). Nine parameters, which are considered important in NPP design or severe accident progression, were selected among the various thermal hydraulic design parameters. The backpropagation neural network (BPN) was used to determine parameters, which might more strongly affect the severe accident progression, among nine parameters. For training, different input patterns were generated by the latin hypercube sampling (LHS) technique and then different target patterns that contain core uncovery time and vessel failure time were obtained for Young Gwang Nuclear (YGN) Units 3 and 4 using modular accident analysis program (MAAP) 3.0B code. Three different severe accident scenarios, such as two loss of coolant accidents (LOCAs) and station blackout (SBO), were considered in this analysis. Results indicated that design parameters related to refueling water storage tank (RWST), accumulator and steam generator (S/G) have more dominant effects on the progression of severe accidents investigated, compared to the other six parameters. 9 refs., 5 tabs. (Author)

  18. Theoretical and experimental studies of heavy liquid metal thermal hydraulics. Proceedings of a technical meeting

    International Nuclear Information System (INIS)

    Through the Nuclear Energy Department's Technical Working Group on Fast Reactors (TWG-FR), the IAEA provides a forum for exchange of information on national programmes, collaborative assessments, knowledge preservation, and cooperative research in areas agreed by the Member States with fast reactor and partitioning and transmutation development programmes (e.g. accelerator driven systems (ADS)). Trends in advanced fast reactor and ADS designs and technology development are periodically summarized in status reports, symposia, and seminar proceedings prepared by the IAEA to provide all interested IAEA Member States with balanced and objective information. The use of heavy liquid metals (HLM) is rapidly diffusing in different research and industrial fields. The detailed knowledge of the basic thermal hydraulics phenomena associated with their use is a necessary step for the development of the numerical codes to be used in the engineering design of HLM components. This is particularly true in the case of lead or lead-bismuth eutectic alloy cooled fast reactors, high power particle beam targets and in the case of the cooling of accelerator driven sub-critical cores where the use of computational fluid dynamic (CFD) design codes is mandatory. Periodic information exchange within the frame of the TWG-FR has lead to the conclusion that the experience in HLM thermal fluid dynamics with regard to both the theoretical/numerical and experimental fields was limited and somehow dispersed. This is the case, e.g. when considering turbulent exchange phenomena, free-surface problems, and two-phase flows. Consequently, Member States representatives participating in the 35th Annual Meeting of the TWG-FR (Karlsruhe, Germany, 22-26 April 2002) recommended holding a technical meeting (TM) on Theoretical and Experimental Studies of Heavy Liquid Metal Thermal Hydraulics. Following this recommendation, the IAEA has convened the Technical Meeting on Theoretical and Experimental Studies of

  19. Application study of magnetic fluid seal in hydraulic turbine

    International Nuclear Information System (INIS)

    The waterpower resources of our country are abundant, and the hydroelectric power is developed, but at present the main shaft sealing device of hydraulic turbine is easy to wear and tear and the leakage is great. The magnetic fluid seal has the advantages of no contact, no wear, self-healing, long life and so on. In this paper, the magnetic fluid seal would be used in the main shaft of hydraulic turbine, the sealing structure was built the model, meshed the geometry, applied loads and solved by using MULTIPHYSICS in ANSYS software, the influence of the various sealing structural parameters such as tooth width, height, slot width, sealing gap on the sealing property were analyzed, the magnetic fluid sealing device suitable for large-diameter shaft and sealing water was designed, the sealing problem of the hydraulic turbine main shaft was solved effectively which will bring huge economic benefits.

  20. Using CFD as a support tool for the initial study of Hydraulic Turbomachinery

    Directory of Open Access Journals (Sweden)

    José Luis Vicéns

    2014-03-01

    Full Text Available The Engineering Education requires that students acquire an appropriate knowledge on a mathematical computational language as well as on a numerical simulation procedure. The computational language of mathematics usually is taught in advanced courses, once that the curriculum mathematical education is mainly completed; in addition, the numerical simulation is usually located late or even in doctoral studies. In this paper, we propose that the Computational Fluid Dynamics (CFD become to be a teaching-learning tool, instead of a strategic resource only. CFD can be regarded as a transversal skill i.e., as a useful educational tool for the Hydraulic Turbomachines learning, which achieves to overcome some epistemological obstacles of students. We develop a teaching-learning method in which the Tutor Facilitator plays an important role.

  1. The status of studies on fast reactor core thermal hydraulics at PNC

    International Nuclear Information System (INIS)

    An outlook was addressed on investigative activities of the fast reactor core thermal-hydraulics at Power Reactor and Nuclear Fuel Development Corporation. Firstly, a computational modeling to predict flow field under natural circulation decay heat removal condition using multi-dimensional codes and its validation were presented. The validation was carried out through calculations of sodium experiments on an inter-subassembly heat transfer, a transient from forced to natural circulation and an inter-wrapper flow. Secondly, experimental and computational studies were expressed on local blockage with porous media in a fuel subassembly. Lastly, information was presented on an advanced computational code based on a subchannel analysis code. The code is under the development and extended to perform whole core simulation. (author)

  2. Field study comparing the effect of hydraulic mixing on septic tank performance and sludge accumulation.

    Science.gov (United States)

    Almomani, Fares

    2016-03-01

    This study investigates the effect of hydraulic mixing on anaerobic digestion and sludge accumulation in a septic tank. The performance of a septic tank equipped with a hydraulic mixer was compared with that of a similar standard septic tank over a period of 10 months. The study was conducted in two phases: Phase-I - from May to November 2013 (6 months); Phase-II - from January to May 2014 (4 months). Hydraulic mixing effectively reduced the effluent biological oxygen demand (BOD) and total suspended solids, and reduced the sludge accumulation rate in the septic tank. The BOD removal efficiencies during Phase-II were 65% and 75% in the standard septic tank and a septic tank equipped with hydraulic mixer (Smart Digester™), respectively. The effect of hydraulic mixing reduced the rate of sludge accumulation from 0.64 cm/day to 0.27 cm/day, and increased the pump-out interval by a factor of 3. PMID:26208182

  3. Advanced core physics and thermal hydraulics analysis of boiling water reactors using innovative fuel concepts

    International Nuclear Information System (INIS)

    The economical operation of a boiling water reactor (BWR) is mainly achieved by the axially uniform utilization of the nuclear fuel in the assemblies which is challenging because the neutron spectrum in the active reactor core varies with the axial position. More precisely, the neutron spectrum becomes harder the higher the position is resulting in a decrease of the fuel utilization because the microscopic fission cross section is smaller by several orders of magnitude. In this work, the use of two fuel concepts based on a mixed oxide (MOX) fuel and an innovative thorium-plutonium (ThPu) fuel is investigated by a developed simulation model encompassing thermal hydraulics, neutronics, and fuel burnup. The main feature of these fuel concepts is the axially varying enrichment in plutonium which is, in this work, recycled from spent nuclear fuel and shows a high fission fraction of the absorption cross section for fast incident neutron energies. The potential of balancing the overall fuel utilization by an increase of the fission rate in the upper part of the active height with a combination of the harder spectrum and the higher fission fraction of the absorption cross section in the BWR core is studied. The three particular calculational models for thermal hydraulics, neutronics, and fuel burnup provide results at fuel assembly and/or at core level. In the former case, the main focus lies on the thermal hydraulics analysis, fuel burnup, and activity evolution after unloading from the core and, in the latter case, special attention is paid to reactivity safety coefficients (feedback effects) and the optimization of the operational behavior. At both levels (assembly and core), the isotopic buildup and depletion rates as a function of the active height are analyzed. In addition, a comparison between the use of conventional fuel types with homogeneous enrichments and the use of the innovative fuel types is made. In the framework of the simulations, the ThPu and the MOX

  4. 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

  5. Experimental thermal hydraulic studies on the enhancement of safety od LWRs

    International Nuclear Information System (INIS)

    The safe use of nuclear power plants (NPPs) requires a deep understanding of the functioning of physical processes and systems involved. Studies on thermal hydraulics have been carried out in various separate effects and integral test facilities at Lappeenranta University of Technology (LUT) either to ensure the functioning of safety systems of light water reactors (LWR) or to produce validation data for the computer codes used in safety analyses of NPPs. Several examples of safety studies on thermal hydraulics of the nuclear power plants are discussed. Studies are related to the physical phenomena existing in different processes in NPPs, such as rewetting of the fuel rods, emergency core cooling (ECC), natural circulation, small break loss-of-coolant accidents (SBLOCA), non-condensable gas release and transport, and passive safety systems. Studies on both VVER and advanced light water reactor (ALWR) systems are included. The set of cases include separate effects tests for understanding and modeling a single physical phenomenon, separate effects tests to study the behavior of a NPP component or a single system, and integral tests to study the behavior of the whole system. In the studies following steps can be found, not necessarily in the same study. Experimental studies as such have provided solutions to existing design problems. Experimental data have been created to validate a single model in a computer code. Validated models are used in various transient analyses of scaled facilities or NPPs. Integral test data are used to validate the computer codes as whole, to see how the implemented models work together in a code. In the final stage test results from the facilities are transferred to the NPP scale using computer codes. Some of the experiments have confirmed the expected behavior of the system or procedure to be studied; in some experiments there have been certain unexpected phenomena that have caused changes to the original design to avoid the recognized

  6. Advanced Clothing Studies

    Science.gov (United States)

    Orndoff, Evelyne; Poritz, Darwin

    2014-01-01

    All human space missions require significant logistical mass and volume that add an unprecedented burden on longduration missions beyond low-Earth orbit. For these missions with limited cleaning resources, a new wardrobe must be developed to reduce this logistical burden by reducing clothing mass and extending clothing wear. The present studies have been undertaken, for the first time, to measure length of wear and to assess the acceptance of such extended wear. Garments in these studies are commercially available exercise T-shirts and shorts, routine-wear T-shirts, and longsleeved pullover shirts. Fabric composition (cotton, polyester, light-weight, superfine Merino wool, modacrylic, cotton/rayon, polyester/Cocona, modacrylic/Xstatic, modacrylic/rayon, modacrylic/lyocell/aramid), construction (open knit, tight knit, open weave, tight weave), and finishing treatment (none, quaternary ammonium salt) are the independent variables. Eleven studies are reported here: five studies of exercise T-shirts, three of exercise shorts, two of routine wear Tshirts, and one of shirts used as sleep-wear. All studies are conducted in a climate-controlled environment, similar to a space vehicle's. For exercise clothing, study participants wear the garments during aerobic exercise. For routine wear clothing, study participants wear the T-shirts daily in an office or laboratory. Daily questionnaires collected data on ordinal preferences of nine sensory elements and on reason for retiring a used garment. Study 1 compares knitted cotton, polyester, and Merino exercise T-shirts (61 participants), study 2, knitted polyester, modacrylic, and polyester/Cocona exercise T-shirts (40 participants), study 3, cotton and polyester exercise shorts, knitted and woven (70 participants), all three using factorial experimental designs with and without a finishing treatment, conducted at the Johnson Space Center, sharing study participants. Study 4 compares knitted polyester and ZQ Merino exercise T

  7. Benchmarking of thermal hydraulic loop models for Lead-Alloy Cooled Advanced Nuclear Energy System (LACANES), phase-I: Isothermal steady state forced convection

    International Nuclear Information System (INIS)

    As highly promising coolant for new generation nuclear reactors, liquid Lead-Bismuth Eutectic has been extensively worldwide investigated. With high expectation about this advanced coolant, a multi-national systematic study on LBE was proposed in 2007, which covers benchmarking of thermal hydraulic prediction models for Lead-Alloy Cooled Advanced Nuclear Energy System (LACANES). This international collaboration has been organized by OECD/NEA, and nine organizations - ENEA, ERSE, GIDROPRESS, IAEA, IPPE, KIT/IKET, KIT/INR, NUTRECK, and RRC KI - contribute their efforts to LACANES benchmarking. To produce experimental data for LACANES benchmarking, thermal-hydraulic tests were conducted by using a 12-m tall LBE integral test facility, named as Heavy Eutectic liquid metal loop for integral test of Operability and Safety of PEACER (HELIOS) which has been constructed in 2005 at the Seoul National University in the Republic of Korea. LACANES benchmark campaigns consist of a forced convection (phase-I) and a natural circulation (phase-II). In the forced convection case, the predictions of pressure losses based on handbook correlations and that obtained by Computational Fluid Dynamics code simulation were compared with the measured data for various components of the HELIOS test facility. Based on comparative analyses of the predictions and the measured data, recommendations for the prediction methods of a pressure loss in LACANES were obtained. In this paper, results for the forced convection case (phase-I) of LACANES benchmarking are described.

  8. Copper River hydraulic study at Million Dollar Bridge, Alaska

    Science.gov (United States)

    Jones, Stanley H.; Barber, William F.

    1980-01-01

    The Copper River hydraulic conditions in the vicinity of the Million-Dollar Bridge, Alaska, at the outlet to Miles Lake are described. The water discharge, lake and river bed profiles, bathymetry, velocity, and direction of flow are presented. (Kosco-USGS)

  9. Experimental study of hydraulic transport of coarse basalt

    Czech Academy of Sciences Publication Activity Database

    Matoušek, Václav; Vlasák, Pavel; Chára, Zdeněk; Konfršt, Jiří

    2015-01-01

    Roč. 148, č. 2 (2015), s. 93-100. ISSN 1741-7597 R&D Projects: GA ČR GAP105/10/1574 Institutional support: RVO:67985874 Keywords : hydraulic s * hydrodynamics * dredging * pipes * pipelines Subject RIV: BK - Fluid Dynamics Impact factor: 0.312, year: 2014

  10. STUDY ON CARRIER PURIFICATION TECHNOLOGY FOR HYDRAULIC OIL

    Institute of Scientific and Technical Information of China (English)

    ZhangXi

    1996-01-01

    The surface feature of contaminative oil is analysed and the theory of carrier purification technology for hydraulic oil is put forward.Experiments have been done in laboratory.The main performance of the purified oil has got to a level of new oil.

  11. Experimental study of hydraulic transport of coarse basalt

    Czech Academy of Sciences Publication Activity Database

    Matoušek, Václav; Vlasák, Pavel; Chára, Zdeněk; Konfršt, Jiří

    2015-01-01

    Roč. 148, č. 2 (2015), s. 93-100. ISSN 1741-7597 R&D Projects: GA ČR GAP105/10/1574 Institutional support: RVO:67985874 Keywords : hydraulics * hydrodynamics * dredging * pipes * pipelines Subject RIV: BK - Fluid Dynamics Impact factor: 0.312, year: 2014

  12. Validation of thermal hydraulic computer codes for advanced light water reactor

    International Nuclear Information System (INIS)

    The Czech Republic operates 4 WWER-440 units, two WWER-1000 units are being finalised (one of them is undergoing commissioning). Thermal-hydraulics Department of the Nuclear Research Institute Rez performs accident analyses for these plants using a number of computer codes. To model the primary and secondary circuits behaviour the system codes ATHLET, CATHARE, RELAP, TRAC are applied. Containment and pressure-suppressure system are modelled with RALOC and MELCOR codes, the reactor power calculations (point and space-neutron kinetics) are made with DYN3D, NESTLE and CDF codes (FLUENT, TRIO) are used for some specific problems. An integral part of the current Czech project 'New Energy Sources' is selection of a new nuclear source. Within this and the preceding projects financed by the Czech Ministry of Industry and Trade and the EU PHARE, the Department carries and has carried out the systematic validation of thermal-hydraulic and reactor physics computer codes applying data obtained on several experimental facilities as well as the real operational data. The paper provides a concise information on these activities of the NRI and its Thermal-hydraulics Department. A detailed example of the system code validation and the consequent utilisation of the results for a real NPP purposes is included. (author)

  13. Electro-hydraulic forming of advanced high-strength steels: Deformation and microstructural characterization

    Energy Technology Data Exchange (ETDEWEB)

    Rohatgi, Aashish; Stephens, Elizabeth V.; Edwards, Danny J.; Smith, Mark T.; Davies, Richard W.

    2012-06-08

    This conference manuscript describes mechanical and microstructural characterization of steel sheets that were deformed via the electro-hydraulic forming technique. The manuscripts shows the importance of the experimental technique developed at PNNL in the sense that the deformation history information enabled by this technique is not obtainable through existing conventional approaches. Additionally, strain-rate effects on texture development during sheet-forming at high-rates are described. Thus, we have demonstrated that it is now possible to correlate deformation history with microstructural development during high-rate forming, a capability that is unique to PNNL.

  14. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington

    2003-04-30

    Experiments on the flow loop are continuing. Improvements to the software for data acquisition are being made as additional experience with three-phase flow is gained. Modifications are being made to the Cuttings Injection System in order to improve control and the precision of cuttings injection. The design details for a drill-pipe Rotation System have been completed. A US Patent was filed on October 28, 2002 for a new design for an instrument that can generate a variety of foams under elevated pressures and temperatures and then transfer the test foam to a viscometer for measurements of viscosity. Theoretical analyses of cuttings transport phenomena based on a layered model is under development. Calibrations of two nuclear densitometers have been completed. Baseline tests have been run to determine wall roughness in the 4 different tests sections (i.e. 2-in, 3-in, 4-in pipes and 5.76-in by 3.5-in annulus) of the flow loop. Tests have also been conducted with aerated fluids at EPET conditions. Preliminary experiments on the two candidate aqueous foam formulations were conducted which included rheological tests of the base fluid and foam stability reports. These were conducted after acceptance of the proposal on the Study of Cuttings Transport with Foam Under Elevated Pressure and Elevated Temperature Conditions. Preparation of a test matrix for cuttings-transport experiments with foam in the ACTF is also under way. A controller for instrumentation to measure cuttings concentration and distribution has been designed that can control four transceivers at a time. A prototype of the control circuit board was built and tested. Tests showed that there was a problem with radiated noise. AN improved circuit board was designed and sent to an external expert to verify the new design. The new board is being fabricated and will first be tested with static water and gravel in an annulus at elevated temperatures. A series of viscometer tests to measure foam properties have

  15. Thermo-hydraulic behaviour of Boom clay using a heating cell: an experimental study

    OpenAIRE

    Lima, A; Romero Morales, Enrique Edgar; Gens Solé, Antonio; Li, X. L.; Vaunat, Jean

    2012-01-01

    Boom clay formation is a potential host rock for geological disposal of high-level nuclear waste in Belgium. Heating pulse tests with controlled power supply and controlled hydraulic boundary conditions were performed under constant volume conditions to study the hydraulic impact of thermal loading on the clay. Selected test result s of intact borehole samples retrieved in horizontal direction are presented a nd discussed. The study focuses on the time evolution of temperature and po...

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

    International Nuclear Information System (INIS)

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

  17. 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.

  18. STUDY OF A FAULT DIAGNOSIS EXPERT SYSTEM FOR SYNTHETIC MINING SYSTEM HYDRAULIC SUPPORT

    Institute of Scientific and Technical Information of China (English)

    Han Yilun

    2000-01-01

    Fault diagnosis expert system for hydraulic support is studied.The system is achieved by Turbo-prolong Language, it summaries the experience of the domain expert and sets up a fault tree, knowledge base is developed by a productive rule.According to the feature of diagnosis, the system selects forward non-determination inferring and limited depth-first search strategy.It can accomplish expert diagnosis of more than 50 kinds faults in hydraulic support.

  19. Advances and future of ship hydraulic propulsion technology%船舶液压推进技术评述

    Institute of Scientific and Technical Information of China (English)

    纪玉龙; 张英; 郭阳; 孙玉清

    2011-01-01

    Ship hydraulic propulsion technology is analyzed and,the development and research status of ship hydraulic propulsion technology is summarized,and the prospect and development trend of the technology is discussed.Results show that the development of hydraulic propulsion technology in china is slow,and the further research should be focused on such aspects as high efficiency dive system design,intelligent and modular components design,noise reduction and strengthening system operating conditions matching performance,etc.With the further study of the technology,hydraulic propulsion technology will play more and more important role in military ships,civil ships and submersible boats,and it is expected to be the first choice for some special ships.%对船舶液压推进技术进行论述,并对其发展过程以及现状进行总结,在此基础上探讨液压推进技术的前景以及研究方向.液压推进技术在我国发展比较缓慢,对其深入研究应集中于高效传动方案设计、元件智能化以及模块化、降低噪声、强化系统工况匹配性能等方面.随着对该技术研究的深入,液压推进技术将在军用船舶、民用作业船舶以及深潜器等领域发挥越来越重要的作用,并有望成为某些特种船舶的首选推进方式.

  20. Power generation costs and ultimate thermal hydraulic power limits in hypothetical advanced designs with natural circulation

    International Nuclear Information System (INIS)

    Maximum power limits for hypothetical designs of natural circulation plants can be described analytically. The thermal hydraulic design parameters are those which limit the flow, being the elevations, flow areas, and loss coefficients. WE have found some simple ''design'' equations for natural circulation flow to power ratio, and for the stability limit. The analysis of historical and available data for maximum capacity factor estimation shows 80% to be reasonable and achievable. The least cost is obtained by optimizing both hypothetical plant performance for a given output,a nd the plant layout and design. There is also scope to increase output and reduce cost by considering design variations of primary and secondary pressure, and by optimizing component elevations and loss coefficients. The design limits for each are set by stability and maximum flow considerations, which deserve close and careful evaluation

  1. Thermal-hydraulic experiments of an advanced PIUS-type reactor

    International Nuclear Information System (INIS)

    The author constructed a semi-large scale experimental apparatus for simulating thermal-hydraulic behavior of the PIUS-type reactor with keeping the volumetric scaling ratio to the realistic reactor model. Fundamental experiments such as a steady state operation and a pump trip simulation were reported in ICONE-3(1995). In this paper the authors present two main results. One is a feedback control system using the upper density lock, and a start up simulation based on the non-uniform heating for both the primary loop and the poison loop. The other is a control system of small scale sub-loop attached to the poison loop in order to establish PIUS principle on the realistic operation of the PIUS-type reactor

  2. Conceptual study of advanced PWR core design

    International Nuclear Information System (INIS)

    The purpose of this project is for developing and verifying the core design concepts with enhanced safety and economy, and associated methodologies for core analyses. From the study of the sate-of-art of foreign advanced reactor cores, we developed core concepts such as soluble boron free, high convertible and enhanced safety core loaded semi-tight lattice hexagonal fuel assemblies. To analyze this hexagonal core, we have developed and verified some neutronic and T/H analysis methodologies. HELIOS code was adopted as the assembly code and HEXFEM code was developed for hexagonal core analysis. Based on experimental data in hexagonal lattices and the COBRA-IV-I code, we developed a thermal-hydraulic analysis code for hexagonal lattices. Using the core analysis code systems developed in this project, we designed a 600 MWe core and studied the feasibility of the core concepts. Two additional scopes were performed in this project : study on the operational strategies of soluble boron free core and conceptual design of large scale passive core. By using the axial BP zoning concept and suitable design of control rods, this project showed that it was possible to design a soluble boron free core in 600 MWe PWR. The results of large scale core design showed that passive concepts and daily load follow operation could be practiced. (author). 15 refs., 52 tabs., 101 figs

  3. Conceptual study of advanced PWR core design

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Jin; Chang, Moon Hee; Kim, Keung Ku; Joo, Hyung Kuk; Kim, Young Il; Noh, Jae Man; Hwang, Dae Hyun; Kim, Taek Kyum; Yoo, Yon Jong

    1997-09-01

    The purpose of this project is for developing and verifying the core design concepts with enhanced safety and economy, and associated methodologies for core analyses. From the study of the sate-of-art of foreign advanced reactor cores, we developed core concepts such as soluble boron free, high convertible and enhanced safety core loaded semi-tight lattice hexagonal fuel assemblies. To analyze this hexagonal core, we have developed and verified some neutronic and T/H analysis methodologies. HELIOS code was adopted as the assembly code and HEXFEM code was developed for hexagonal core analysis. Based on experimental data in hexagonal lattices and the COBRA-IV-I code, we developed a thermal-hydraulic analysis code for hexagonal lattices. Using the core analysis code systems developed in this project, we designed a 600 MWe core and studied the feasibility of the core concepts. Two additional scopes were performed in this project : study on the operational strategies of soluble boron free core and conceptual design of large scale passive core. By using the axial BP zoning concept and suitable design of control rods, this project showed that it was possible to design a soluble boron free core in 600 MWe PWR. The results of large scale core design showed that passive concepts and daily load follow operation could be practiced. (author). 15 refs., 52 tabs., 101 figs.

  4. Experimental Study For Pizometric Head Distribution Under Hydraulic Structures

    Directory of Open Access Journals (Sweden)

    Dr. Najm Obaid Salim Alghazali

    2015-04-01

    Full Text Available Abstract In this research the experimental method by using Hydraulic modeling used to determination the flow net in order to analyses seepage flow through single- layer soil foundation underneath hydraulic structure. as well as steady the consequence of the cut-off inclination angle on exit gradient factor of safety uplift pressure and quantity of seepage by using seepage tank were designed in the laboratory with proper dimensions with two cutoffs . The physical model seepage tank was designed in two downstream cutoff angles which are 90 and 120 and upstream cutoff angles 90 45 120. After steady state flow the flow line is constructed by dye injection in the soil from the upstream side in front view of the seepage tank and the equipotentials line can be constructed by pizometer fixed to measure the total head. From the result It is concluded that using downstream cut-off inclined towards the downstream side with amp1256 equal 120 that given value of redaction 25 is beneficial in increasing the safety factor against the piping phenomenon. using upstream cut-off inclined towards the downstream side with amp1256 equal 45 that given value of redaction 52 is beneficial in decreasing uplift pressure and quantity of seepage.

  5. Hydraulic study of parallel channels coupled to recirculation loops

    International Nuclear Information System (INIS)

    In this work is integrated a model of recirculation loops that allows to characterize each loop for separate and with which is possible to analyze events as shot of recirculation bombs or its transfer of high to low speed. The recirculation pattern is integrated to a model of 36 channels in parallel that represents the core of a BWR. Because the core reactor is conformed by fuel assemblies physically prepared in a parallel arrangement, it is natural to obtain a parallel application of complete pattern, where are have 36 channels tasks more other two tasks that calculates recirculation and punctual kinetics, respectively. As initial test of system, which even it is found in development, was analyzed a discharge of both recirculation pumps. In this test transitory it is only verified the hydraulic behavior, the power is imposed artificially as frontier condition that is function of flow in the calculated core by the recirculation pattern. The pattern of thermal hydraulics channel and the recirculation loops are programmed in language C, the neutronic pattern is programmed in Fortran 77. For the simulations was used a work station Alpha Station DS20E with operative system Unix and the communication system Parallel Virtual Machine, that allows to a heterogeneous collection of computers in net to work like a virtual computer in parallel. (Author)

  6. Proceedings of the Twenty-First Water Reactor Safety Information Meeting: Volume 1, Plenary session; Advanced reactor research; advanced control system technology; advanced instrumentation and control hardware; human factors research; probabilistic risk assessment topics; thermal hydraulics; thermal hydraulic research for advanced passive LWRs

    International Nuclear Information System (INIS)

    This three-volume report contains 90 papers out of the 102 that were presented at the Twenty-First Water Reactor Safety Information Meeting held at the Bethesda Marriott Hotel, Bethesda, Maryland, during the week of October 25--27, 1993. The papers are printed in the order of their presentation in each session and describe progress and results of programs in nuclear safety research conducted in this country and abroad. Foreign participation in the meeting included papers presented by researchers from France, Germany, Japan, Russia, Switzerland, Taiwan, and United Kingdom. The titles of the papers and the names of the authors have been updated and may differ from those that appeared in the final program of the meeting. Individual papers have been cataloged separately. This document, Volume 1 covers the following topics: Advanced Reactor Research; Advanced Instrumentation and Control Hardware; Advanced Control System Technology; Human Factors Research; Probabilistic Risk Assessment Topics; Thermal Hydraulics; and Thermal Hydraulic Research for Advanced Passive Light Water Reactors

  7. Proceedings of the Twenty-First Water Reactor Safety Information Meeting: Volume 1, Plenary session; Advanced reactor research; advanced control system technology; advanced instrumentation and control hardware; human factors research; probabilistic risk assessment topics; thermal hydraulics; thermal hydraulic research for advanced passive LWRs

    Energy Technology Data Exchange (ETDEWEB)

    Monteleone, S. [Brookhaven National Lab., Upton, NY (United States)] [comp.

    1994-04-01

    This three-volume report contains 90 papers out of the 102 that were presented at the Twenty-First Water Reactor Safety Information Meeting held at the Bethesda Marriott Hotel, Bethesda, Maryland, during the week of October 25--27, 1993. The papers are printed in the order of their presentation in each session and describe progress and results of programs in nuclear safety research conducted in this country and abroad. Foreign participation in the meeting included papers presented by researchers from France, Germany, Japan, Russia, Switzerland, Taiwan, and United Kingdom. The titles of the papers and the names of the authors have been updated and may differ from those that appeared in the final program of the meeting. Individual papers have been cataloged separately. This document, Volume 1 covers the following topics: Advanced Reactor Research; Advanced Instrumentation and Control Hardware; Advanced Control System Technology; Human Factors Research; Probabilistic Risk Assessment Topics; Thermal Hydraulics; and Thermal Hydraulic Research for Advanced Passive Light Water Reactors.

  8. Hydraulic conductivity study of compacted clay soils used as landfill liners for an acidic waste

    International Nuclear Information System (INIS)

    Highlights: ► Examined the hydraulic conductivity evolution as function of dry density of Tunisian clay soil. ► Follow the hydraulic conductivity evolution at long-term of three clay materials using the waste solution (pH=2.7). ► Determined how compaction affects the hydraulic conductivity of clay soils. ► Analyzed the concentration of F and P and examined the retention of each soil. - Abstract: Three natural clayey soils from Tunisia were studied to assess their suitability for use as a liner for an acid waste disposal site. An investigation of the effect of the mineral composition and mechanical compaction on the hydraulic conductivity and fluoride and phosphate removal of three different soils is presented. The hydraulic conductivity of these three natural soils are 8.5 × 10−10, 2.08 × 10−9 and 6.8 × 10−10 m/s for soil-1, soil-2 and soil-3, respectively. Soil specimens were compacted under various compaction strains in order to obtain three wet densities (1850, 1950 and 2050 kg/m3). In this condition, the hydraulic conductivity (k) was reduced with increasing density of sample for all soils. The test results of hydraulic conductivity at long-term (>200 days) using acidic waste solution (pH = 2.7, charged with fluoride and phosphate ions) shows a decrease in k with time only for natural soil-1 and soil-2. However, the specimens of soil-2 compressed to the two highest densities (1950 and 2050 kg/m3) are cracked after 60 and 20 days, respectively, of hydraulic conductivity testing. This damage is the result of a continued increase in the internal stress due to the swelling and to the effect of aggressive wastewater. The analysis of anions shows that the retention of fluoride is higher compared to phosphate and soil-1 has the highest sorption capacity.

  9. Hydraulic test for non-instrumented capsule of advanced PWR fuel pellet

    International Nuclear Information System (INIS)

    This report presents the results of pressure drop test, vibration test and endurance test for Non-instrumented Capsule of Advanced PWR Fuel Pellet which were designed fabricated by KAERI. From the pressure drop test results, it is noted that the flow rate across the Non-instrumented Capsule of Advanced PWR Fuel Pellet corresponding to the pressure drop of 200 kPa is measured to be about 7.45 kg/sec. Vibration frequency for the Non-instrumented Capsule of Advanced PWR Fuel Pellet ranges from 13.0 to 32.3 Hz. RMS(Root Mean Square) displacement for the fuel rig is less than 11.6 μm, and the maximum displacement is less than 30.5 μm. The endurance test was carried out for 103 days and 17 hours

  10. Elements of validation for LWRs thermal hydraulic studies with FLICA-OVAP

    International Nuclear Information System (INIS)

    FLICA-OVAP is an advanced two-phase flow thermal-hydraulics code based on a full 3D subchannel approach. It is designed to analyze flows in Light Water Reactors (LWRs) cores such as PWRs, BWRs and experimental reactors. Therefore its applicability covers all ranges of operating conditions for water-cooled reactors. This paper presents an overview of FLICA-OVAP modeling capabilities for applications in nuclear reactors design and safety analysis. A validation matrix is proposed and its results are presented. The matrix covers a wide range of selected phenomena, which are relevant for thermalhydraulics studies. Therefore the different FLICA-OVAP physical correlations addressed in the current study include single phase and two-phase friction factors, single phase and boiling heat transfer, turbulence and critical heat flux. Results of the FLICA-OVAP validation studies highlight the capabilities of the code to well-predict two-phase flows in Light Water Reactors for both normal operation and under accidental circumstances. Future developments as well as validation activities are also summarized. (author)

  11. Conceptual study on advanced PWR system

    International Nuclear Information System (INIS)

    In this study, the adoptable essential technologies and reference design concept of the advanced reactor were developed and related basic experiments were performed. 1) Once-through Helical Steam Generator: a performance analysis computer code for heli-coiled steam generator was developed for thermal sizing of steam generator and determination of thermal-hydraulic parameters. 2) Self-pressurizing pressurizer : a performance analysis computer code for cold pressurizer was developed. 3) Control rod drive mechanism for fine control : type and function were surveyed. 4) CHF in passive PWR condition : development of the prediction model bundle CHF by introducing the correction factor from the data base. 5) Passive cooling concepts for concrete containment systems: development of the PCCS heat transfer coefficient. 6) Steam injector concepts: analysis and experiment were conducted. 7) Fluidic diode concepts : analysis and experiment were conducted. 8) Wet thermal insulator : tests for thin steel layers and assessment of materials. 9) Passive residual heat removal system : a performance analysis computer code for PRHRS was developed and the conformance to EPRI requirement was checked. (author). 18 refs., 55 tabs., 137 figs

  12. Argonne Liquid-Metal Advanced Burner Reactor : components and in-vessel system thermal-hydraulic research and testing experience - pathway forward.

    Energy Technology Data Exchange (ETDEWEB)

    Kasza, K.; Grandy, C.; Chang, Y.; Khalil, H.; Nuclear Engineering Division

    2007-06-30

    This white paper provides an overview and status report of the thermal-hydraulic nuclear research and development, both experimental and computational, conducted predominantly at Argonne National Laboratory. Argonne from the early 1970s through the early 1990s was the Department of Energy's (DOE's) lead lab for thermal-hydraulic development of Liquid Metal Reactors (LMRs). During the 1970s and into the mid-1980s, Argonne conducted thermal-hydraulic studies and experiments on individual reactor components supporting the Experimental Breeder Reactor-II (EBR-II), Fast Flux Test Facility (FFTF), and the Clinch River Breeder Reactor (CRBR). From the mid-1980s and into the early 1990s, Argonne conducted studies on phenomena related to forced- and natural-convection thermal buoyancy in complete in-vessel models of the General Electric (GE) Prototype Reactor Inherently Safe Module (PRISM) and Rockwell International (RI) Sodium Advanced Fast Reactor (SAFR). These two reactor initiatives involved Argonne working closely with U.S. industry and DOE. This paper describes the very important impact of thermal hydraulics dominated by thermal buoyancy forces on reactor global operation and on the behavior/performance of individual components during postulated off-normal accident events with low flow. Utilizing Argonne's LMR expertise and design knowledge is vital to the further development of safe, reliable, and high-performance LMRs. Argonne believes there remains an important need for continued research and development on thermal-hydraulic design in support of DOE's and the international community's renewed thrust for developing and demonstrating the Global Nuclear Energy Partnership (GNEP) reactor(s) and the associated Argonne Liquid Metal-Advanced Burner Reactor (LM-ABR). This white paper highlights that further understanding is needed regarding reactor design under coolant low-flow events. These safety-related events are associated with the transition

  13. Argonne Liquid-Metal Advanced Burner Reactor : components and in-vessel system thermal-hydraulic research and testing experience - pathway forward

    International Nuclear Information System (INIS)

    This white paper provides an overview and status report of the thermal-hydraulic nuclear research and development, both experimental and computational, conducted predominantly at Argonne National Laboratory. Argonne from the early 1970s through the early 1990s was the Department of Energy's (DOE's) lead lab for thermal-hydraulic development of Liquid Metal Reactors (LMRs). During the 1970s and into the mid-1980s, Argonne conducted thermal-hydraulic studies and experiments on individual reactor components supporting the Experimental Breeder Reactor-II (EBR-II), Fast Flux Test Facility (FFTF), and the Clinch River Breeder Reactor (CRBR). From the mid-1980s and into the early 1990s, Argonne conducted studies on phenomena related to forced- and natural-convection thermal buoyancy in complete in-vessel models of the General Electric (GE) Prototype Reactor Inherently Safe Module (PRISM) and Rockwell International (RI) Sodium Advanced Fast Reactor (SAFR). These two reactor initiatives involved Argonne working closely with U.S. industry and DOE. This paper describes the very important impact of thermal hydraulics dominated by thermal buoyancy forces on reactor global operation and on the behavior/performance of individual components during postulated off-normal accident events with low flow. Utilizing Argonne's LMR expertise and design knowledge is vital to the further development of safe, reliable, and high-performance LMRs. Argonne believes there remains an important need for continued research and development on thermal-hydraulic design in support of DOE's and the international community's renewed thrust for developing and demonstrating the Global Nuclear Energy Partnership (GNEP) reactor(s) and the associated Argonne Liquid Metal-Advanced Burner Reactor (LM-ABR). This white paper highlights that further understanding is needed regarding reactor design under coolant low-flow events. These safety-related events are associated with the transition from normal high

  14. Antiquity versus modern times in hydraulics - a case study

    International Nuclear Information System (INIS)

    Water supply and water management in Antiquity represent more than Modern World can imagine about how people in that period used to think about, and exploit the resources they had, aiming at developing and improving their society and own lives. This paper points out examples of how they handled different situations, and how they managed to cope with the growing number of population in the urban areas, by adapting or by improving their water supply systems. The paper tries to emphasize the engineering contribution of Rome and the Roman Empire, mainly in the capital but also in the provinces, as for instance the today territory of France, by analysing some aqueducts from the point of view of modern Hydraulic Engineering. A third order polynomial regression is proposed to compute the water flow rate, based on the flow cross-sectional area measured in quinaria. This paper also emphasizes on contradictory things between what we thought we knew about Ancient Roman civilization, and what could really be proven, either by a modern engineering approach, a documentary approach, or by commonsense, where none of the above could be used. It is certain that the world we live in is the heritage of the Greco-Roman culture and therefore, we are due to acknowledge their contribution, especially taking into account the lack of knowledge of that time, and the poor resources they had.

  15. Antiquity versus modern times in hydraulics - a case study

    Energy Technology Data Exchange (ETDEWEB)

    Stroia, L [Research Department, Sangari Engineering Services SRL, 35-39 Emil Racovita, Complex Azur 1, AP 08, Voluntari, 077191 (Romania); Georgescu, S C [Hydraulics and Hydraulic Machinery Department, University ' Politehnica' of Bucharest 313 Spl. Independentei, S6, Bucharest, 060042 (Romania); Georgescu, A M, E-mail: liviu.stroia@sangari.r [Hydraulics and Environmental Protection Department, Technical University of Civil Engineering Bucharest, 124 Lacul Tei Bd, S2, Bucharest, 020396 (Romania)

    2010-08-15

    Water supply and water management in Antiquity represent more than Modern World can imagine about how people in that period used to think about, and exploit the resources they had, aiming at developing and improving their society and own lives. This paper points out examples of how they handled different situations, and how they managed to cope with the growing number of population in the urban areas, by adapting or by improving their water supply systems. The paper tries to emphasize the engineering contribution of Rome and the Roman Empire, mainly in the capital but also in the provinces, as for instance the today territory of France, by analysing some aqueducts from the point of view of modern Hydraulic Engineering. A third order polynomial regression is proposed to compute the water flow rate, based on the flow cross-sectional area measured in quinaria. This paper also emphasizes on contradictory things between what we thought we knew about Ancient Roman civilization, and what could really be proven, either by a modern engineering approach, a documentary approach, or by commonsense, where none of the above could be used. It is certain that the world we live in is the heritage of the Greco-Roman culture and therefore, we are due to acknowledge their contribution, especially taking into account the lack of knowledge of that time, and the poor resources they had.

  16. Antiquity versus modern times in hydraulics - a case study

    Science.gov (United States)

    Stroia, L.; Georgescu, S. C.; Georgescu, A. M.

    2010-08-01

    Water supply and water management in Antiquity represent more than Modern World can imagine about how people in that period used to think about, and exploit the resources they had, aiming at developing and improving their society and own lives. This paper points out examples of how they handled different situations, and how they managed to cope with the growing number of population in the urban areas, by adapting or by improving their water supply systems. The paper tries to emphasize the engineering contribution of Rome and the Roman Empire, mainly in the capital but also in the provinces, as for instance the today territory of France, by analysing some aqueducts from the point of view of modern Hydraulic Engineering. A third order polynomial regression is proposed to compute the water flow rate, based on the flow cross-sectional area measured in quinaria. This paper also emphasizes on contradictory things between what we thought we knew about Ancient Roman civilization, and what could really be proven, either by a modern engineering approach, a documentary approach, or by commonsense, where none of the above could be used. It is certain that the world we live in is the heritage of the Greco-Roman culture and therefore, we are due to acknowledge their contribution, especially taking into account the lack of knowledge of that time, and the poor resources they had.

  17. Development and study of thermal-hydraulic code for spiral-space rods assembly

    International Nuclear Information System (INIS)

    Spiral-spacer fuel assembly usually adopts helical fins or wire wrap fuel elements. Compare with the tradition- al PWR fuel rods, spiral spacers make the thermal hydraulic phenomena in sub-channels very complicated. The paper preliminary studied the influence of the spiral spacer to the thermal-hydraulic performance, there is no suitable code to study these affect. A new code named CANAL/CMS was developed base on the VVER code. Using the new code, investigation has been carried out for the influence of the helical fins. Systemic study shows that the impact of the helical fins to the thermal hydraulic of the bundle is great; they improve the ability of the heat transfer of the fuel elements to a certain extent, and the pressure drop add little; the long helical spacer will reduce the pressure drop, but it is bad for CHF. (authors)

  18. Advanced nuclear systems. Review study

    International Nuclear Information System (INIS)

    The task of this review study is to from provide an overview of the developments in the field of the various advanced nuclear systems, and to create the basis for more comprehensive studies of technology assessment. In an overview the concepts for advanced nuclear systems pursued worldwide are subdivided into eight subgroups. A coarse examination raster (set pattern) is developed to enable a detailed examination of the selected systems. In addition to a focus on enhanced safety features, further aspects are also taken into consideration, like the lowering of the proliferation risk, the enhancement of the economic competitiveness of the facilities and new usage possibilities (for instance concerning the relaxation of the waste disposal problem or the usage of alternative fuels to uranium). The question about the expected time span for realization and the discussion about the obstacles on the way to a commercially usable reactor also play a substantial role as well as disposal requirements as far as they can be presently recognized. In the central chapter of this study, the documentation of the representatively selected concepts is evaluated as well as existing technology assessment studies and expert opinions. In a few cases where this appears to be necessary, according technical literature, further policy advisory reports, expert statements as well as other relevant sources are taken into account. Contradictions, different assessments and dissents in the literature as well as a few unsettled questions are thus indicated. The potential of advanced nuclear systems with respect to economical and societal as well as environmental objectives cannot exclusively be measured by the corresponding intrinsic or in comparison remarkable technical improvements. The acceptability of novel or improved systems in nuclear technology will have to be judged by their convincing solutions for the crucial questions of safety, nuclear waste and risk of proliferation of nuclear weapons

  19. Thermal hydraulic simulations, error estimation and parameter sensitivity studies in Drekar::CFD

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Thomas Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Shadid, John N. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Pawlowski, Roger P. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cyr, Eric C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wildey, Timothy Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-01-01

    This report describes work directed towards completion of the Thermal Hydraulics Methods (THM) CFD Level 3 Milestone THM.CFD.P7.05 for the Consortium for Advanced Simulation of Light Water Reactors (CASL) Nuclear Hub effort. The focus of this milestone was to demonstrate the thermal hydraulics and adjoint based error estimation and parameter sensitivity capabilities in the CFD code called Drekar::CFD. This milestone builds upon the capabilities demonstrated in three earlier milestones; THM.CFD.P4.02 [12], completed March, 31, 2012, THM.CFD.P5.01 [15] completed June 30, 2012 and THM.CFD.P5.01 [11] completed on October 31, 2012.

  20. A study on hydraulic properties of compacted Fe(III)-montmorillonite

    International Nuclear Information System (INIS)

    Hydraulic conductivities were determined for compacted Fe(III)-montmorillonite sample. The Fe(III)-montmorillonite sample used in this study, which was prepared by the ion-exchange treatment of Na-montmorillonite in FeCl3 solution, contains less than 20% of Na+ ions as exchangeable cations and negligibly small amounts of iron precipitates. The measured hydraulic conductivities of compacted Fe(III)-montmorillonite were determined to be the order of 10-9, 10-11, and 10-13 m s-1 at dry densities of 0.80, 1.01, and 1.20 Mg m-3, respectively. These values were found to be kept constant during the experimental period, suggesting no significant change in the physicochemical properties of Fe(III)-montmorillonite during the experiment. When compared with Na-montmorillonite, remarkably high values of hydraulic conductivities were found for Fe(III)-montmorillonite at the dry densities of 0.8 and 1.0 Mg m-3. On the other hand, almost the same value of hydraulic conductivity was obtained at the dry density around 1.2 Mg m-3. This different effect of exchangeable cations on the hydraulic conductivity of montmorillonite could be attributed to the different sizes of macropores in compacted montmorillonite and/or the different thicknesses of electrical double layers formed over montmorillonite sheets. (author)

  1. Comparative study of Thermal Hydraulic Analysis Codes for Pressurized Water Reactors

    International Nuclear Information System (INIS)

    Various codes are used for the thermal hydraulic analysis of nuclear reactors. The use of some codes among these is limited by user and some codes are not even open to general person. Thus, the use of alternative code is considered for some analysis. In this study, simple thermal hydraulic behaviors are analyzed using three codes to show that alternative codes are possible for the analysis of nuclear reactors. We established three models of the simple u-tube manometer using three different codes. RELAP5 (Reactor Excursion and Leak Analysis Program), SPACE (Safety and Performance Analysis CodE for nuclear power Plants), GOTHIC (Generation of Thermal Hydraulic Information for Containments) are selected for this analysis. RELAP5 is widely used codes for the analysis of system behavior of PWRs. SPACE has been developed based on RELAP5 for the analysis of system behavior of PWRs and licensing of the code is in progress. And GOTHIC code also has been widely used for the analysis of thermal hydraulic behavior in the containment system. The internal behavior of u-tube manometer was analyzed by RELAP5, SPACE and GOTHIC codes. The general transient behavior was similar among 3 codes. However, the stabilized status of the transient period analyzed by REPAP5 was different from the other codes. It would be resulted from the different physical models used in the other codes, which is specialized for the multi-phase thermal hydraulic behavior analysis

  2. Comparative study of Thermal Hydraulic Analysis Codes for Pressurized Water Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yang Hoon; Jang, Mi Suk; Han, Kee Soo [Nuclear Engineering Service and Solution Co. Ltd., Daejeon (Korea, Republic of)

    2015-05-15

    Various codes are used for the thermal hydraulic analysis of nuclear reactors. The use of some codes among these is limited by user and some codes are not even open to general person. Thus, the use of alternative code is considered for some analysis. In this study, simple thermal hydraulic behaviors are analyzed using three codes to show that alternative codes are possible for the analysis of nuclear reactors. We established three models of the simple u-tube manometer using three different codes. RELAP5 (Reactor Excursion and Leak Analysis Program), SPACE (Safety and Performance Analysis CodE for nuclear power Plants), GOTHIC (Generation of Thermal Hydraulic Information for Containments) are selected for this analysis. RELAP5 is widely used codes for the analysis of system behavior of PWRs. SPACE has been developed based on RELAP5 for the analysis of system behavior of PWRs and licensing of the code is in progress. And GOTHIC code also has been widely used for the analysis of thermal hydraulic behavior in the containment system. The internal behavior of u-tube manometer was analyzed by RELAP5, SPACE and GOTHIC codes. The general transient behavior was similar among 3 codes. However, the stabilized status of the transient period analyzed by REPAP5 was different from the other codes. It would be resulted from the different physical models used in the other codes, which is specialized for the multi-phase thermal hydraulic behavior analysis.

  3. Argonne Liquid-Metal Advanced Burner Reactor : components and in-vessel system thermal-hydraulic research and testing experience - pathway forward.

    Energy Technology Data Exchange (ETDEWEB)

    Kasza, K.; Grandy, C.; Chang, Y.; Khalil, H.; Nuclear Engineering Division

    2007-06-30

    This white paper provides an overview and status report of the thermal-hydraulic nuclear research and development, both experimental and computational, conducted predominantly at Argonne National Laboratory. Argonne from the early 1970s through the early 1990s was the Department of Energy's (DOE's) lead lab for thermal-hydraulic development of Liquid Metal Reactors (LMRs). During the 1970s and into the mid-1980s, Argonne conducted thermal-hydraulic studies and experiments on individual reactor components supporting the Experimental Breeder Reactor-II (EBR-II), Fast Flux Test Facility (FFTF), and the Clinch River Breeder Reactor (CRBR). From the mid-1980s and into the early 1990s, Argonne conducted studies on phenomena related to forced- and natural-convection thermal buoyancy in complete in-vessel models of the General Electric (GE) Prototype Reactor Inherently Safe Module (PRISM) and Rockwell International (RI) Sodium Advanced Fast Reactor (SAFR). These two reactor initiatives involved Argonne working closely with U.S. industry and DOE. This paper describes the very important impact of thermal hydraulics dominated by thermal buoyancy forces on reactor global operation and on the behavior/performance of individual components during postulated off-normal accident events with low flow. Utilizing Argonne's LMR expertise and design knowledge is vital to the further development of safe, reliable, and high-performance LMRs. Argonne believes there remains an important need for continued research and development on thermal-hydraulic design in support of DOE's and the international community's renewed thrust for developing and demonstrating the Global Nuclear Energy Partnership (GNEP) reactor(s) and the associated Argonne Liquid Metal-Advanced Burner Reactor (LM-ABR). This white paper highlights that further understanding is needed regarding reactor design under coolant low-flow events. These safety-related events are associated with the transition

  4. Study of Hydraulic properties (porosity and saturated hydraulic conductivity of the quaternary aquifer of Abidjan (Côte d'Ivoire

    Directory of Open Access Journals (Sweden)

    Kouadio KOFFI

    2013-05-01

    Full Text Available The hydraulic properties of the soil are important parameters in hydrogeology. They allow knowing the characteristics and functioning of aquifers. But their determination is costly and difficult on large sites such as the quaternary aquifer of Abidjan. The objective is to know the hydraulic properties of the aquifer of Abidjan through the study of the porosity and the prediction of saturated hydraulic conductivity by the modified Kozeny Carman's model. The predicted conductivities are compared to those measured in situ by the double rings infiltrability method. The work showed that the porosities ranging from 0.25 to 0.42 while the hydraulic conductivities from 2.10-5 to 5.10-5 m/s. The quaternary aquifer of Abidjan is composed of coarse sand of the marine cordon and medium sand of the lagoon depressions. The coarse sands are found in the southern part of the aquifer while the medium sands in the north part.The application of the modified Kozeny Carman model showed that the predicted conductivities are close to those measured in situ. This model can be used to predict the hydraulic conductivity of the sands of the quaternary aquifer. The model has the merit of using the basic physical properties of the soil easily accessible. It could therefore be applied to other sandy aquifers along of whole eburneo basin of the West Africa.

  5. Advance of the upsetting technology theory and technique in a hydraulic press

    International Nuclear Information System (INIS)

    The tension stress theory of a rigid-plastic mechanical model when the ratio of height to diameter (HID) larger than 1 and the shearing stress theory if a hydrostatic stress mechanical model when HID less than 1 are advanced for the problem of upsetting a cylinder between common flat platens. The former breaks the saying described in traditional engineering plastic mechanics that there always exist three-dimensional compressive stresses in the interior of an upsetting body. The latter perfectly interprets the problem that there often present the flaws with meat pie in the heavy forgings. The new theory of flat platen upsetting has been testified by the qualitative physical simulation, the quantitative numerical simulation, the generalized slip-line solution, the mechanical slab method and the dissecting test in production. Two new mechanical model for upsetting a square body and the new technology and its mechanical principal of upsetting between the cone-shaped platens are further proposed on the basis of the new theory

  6. Advanced Collaborative Emissions Study (ACES)

    Energy Technology Data Exchange (ETDEWEB)

    Greenbaum, Daniel; Costantini, Maria; Van Erp, Annemoon; Shaikh, Rashid; Bailey, Brent; Tennant, Chris; Khalek, Imad; Mauderly, Joe; McDonald, Jacob; Zielinska, Barbara; Bemis, Jeffrey; Storey, John; Hallberg, Lance; Clark, Nigel

    2013-12-31

    The objective of the Advanced Collaborative Emissions Study (ACES) was to determine before widespread commercial deployment whether or not the new, energy-efficient, heavy duty diesel engines (2007 and 2010 EPA Emissions Standards Compliant) may generate anticipated toxic emissions that could adversely affect the environment and human health. ACES was planned to take place in three phases. In Phase 1, extensive emissions characterization of four production-intent prototype engine and control systems designed to meet 2007 standards for nitrogen oxides (NOx) and particulate matter (PM) was conducted at an existing emissions characterization facility: Southwest Research Institute (SwRI). One of the tested engines was selected (at random, after careful comparison of results) for health testing in Phase 3. In Phase 2, extensive emission characterization of three production-intent prototype engine and control systems meeting the 2010 standards (including more advanced NOx controls to meet the more stringent 2010 NOx standards) was conducted at the same test facility. In Phase 3, one engine/aftertreatment system selected from Phase 1 was further characterized during health effects studies (at an existing inhalation toxicology laboratory: Lovelace Respiratory Research Institute, [LRRI]) to form the basis of the ACES safety assessment. The Department of Energy (DOE) award provided funding for emissions characterization in Phases 1 and 2 as well as exposure characterization in Phase 3. The main health analyses in Phase 3 were funded separately and are not reported here.

  7. Thermal hydraulic analysis due to the changes in heat removal for advanced heavy water reactor

    International Nuclear Information System (INIS)

    Advanced Heavy Water Reactor is a natural circulation light water cooled and heavy water moderated pressure tube reactor. Changes in heat removal by primary heat transport system of the reactor have significant impact on various important system parameters like pressures, qualities, reactor power and flows. Increase in heat removal leads to the cooldown of the system subsequently reducing pressure, void increase and changes in power and flows of the system. Decrease in heat removal leads to warm-up of the system subsequently raising pressure, void collapse, and changes in power and flows of the system. The behaviour is complex as system under consideration is natural circulation system. This article presents the results of simulations made with the RELAP5-MOD3.2 code that show first the impact of a decrease in feed water temperature on fluid temperature, steam drum pressure, core exit void, reactivity, reactor power, core flow, steam flow and clad temperature and secondly the impact of a loss of normal feed water flow on steam drum pressure, channel flow, core quality, clad surface temperature. For lowering of feed water temperature transient and in isolation condensers cold water injection, the reactor power increases and the reactor trips on the high power signal. Simultaneous flow increment due to the 2 phase natural circulation characteristic has caused the clad temperature to limit to their steady state value. In case of loss of feed transient the reactor trips on high pressure. The clad surface temperature rise from steady state operating value is marginal and it is well within the safety limit as per the acceptance criteria

  8. Statistically based uncertainty analysis for ranking of component importance in the thermal-hydraulic safety analysis of the Advanced Neutron Source Reactor

    International Nuclear Information System (INIS)

    The Analytic Hierarchy Process (AHP) has been used to help determine the importance of components and phenomena in thermal-hydraulic safety analyses of nuclear reactors. The AHP results are based, in part on expert opinion. Therefore, it is prudent to evaluate the uncertainty of the AHP ranks of importance. Prior applications have addressed uncertainty with experimental data comparisons and bounding sensitivity calculations. These methods work well when a sufficient experimental data base exists to justify the comparisons. However, in the case of limited or no experimental data the size of the uncertainty is normally made conservatively large. Accordingly, the author has taken another approach, that of performing a statistically based uncertainty analysis. The new work is based on prior evaluations of the importance of components and phenomena in the thermal-hydraulic safety analysis of the Advanced Neutron Source Reactor (ANSR), a new facility now in the design phase. The uncertainty during large break loss of coolant, and decay heat removal scenarios is estimated by assigning a probability distribution function (pdf) to the potential error in the initial expert estimates of pair-wise importance between the components. Using a Monte Carlo sampling technique, the error pdfs are propagated through the AHP software solutions to determine a pdf of uncertainty in the system wide importance of each component. To enhance the generality of the results, study of one other problem having different number of elements is reported, as are the effects of a larger assumed pdf error in the expert ranks. Validation of the Monte Carlo sample size and repeatability are also documented

  9. Preliminary Thermo-hydraulic Core Design Analysis of Korea Advanced Nuclear Thermal Engine Rocket for Space Application

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Seung Hyun; Lee, Jeong Ik; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2014-05-15

    Nclear rockets improve the propellant efficiency more than twice compared to CRs and thus significantly reduce the propellant requirement. The superior efficiency of nuclear rockets is due to the combination of the huge energy density and a single low molecular weight propellant utilization. Nuclear Thermal Rockets (NTRs) are particularly suitable for manned missions to Mars because it satisfies a relatively high thrust as well as a high propellant efficiency. NTRs use thermal energy released from a nuclear fission reactor to heat a single low molecular weight propellant, i. e., Hydrogen (H{sub 2}) and then exhausted the extremely heated propellant through a thermodynamic nozzle to produce thrust. A propellant efficiency parameter of rocket engines is specific impulse (I{sub sp}) which represents the ratio of the thrust over the rate of propellant consumption. The difference of I{sub sp} makes over three times propellant savings of NTRs for a manned Mars mission compared to CRs. NTRs can also be configured to operate bimodally by converting the surplus nuclear energy to auxiliary electric power required for the operation of a spacecraft. Moreover, the concept and technology of NTRs are very simple, already proven, and safe. Thus, NTRs can be applied to various space missions such as solar system exploration, International Space Station (ISS) transport support, Near Earth Objects (NEOs) interception, etc. Nuclear propulsion is the most promising and viable option to achieve challenging deep space missions. Particularly, the attractions of a NTR include excellent thrust and propellant efficiency, bimodal capability, proven technology, and safe and reliable performance. The ROK has also begun the research for space nuclear systems as a volunteer of the international space race and a major world nuclear energy country. KANUTER is one of the advanced NTR engines currently under development at KAIST. This bimodal engine is operated in two modes of propulsion with 100 MW

  10. Preliminary Thermo-hydraulic Core Design Analysis of Korea Advanced Nuclear Thermal Engine Rocket for Space Application

    International Nuclear Information System (INIS)

    Nclear rockets improve the propellant efficiency more than twice compared to CRs and thus significantly reduce the propellant requirement. The superior efficiency of nuclear rockets is due to the combination of the huge energy density and a single low molecular weight propellant utilization. Nuclear Thermal Rockets (NTRs) are particularly suitable for manned missions to Mars because it satisfies a relatively high thrust as well as a high propellant efficiency. NTRs use thermal energy released from a nuclear fission reactor to heat a single low molecular weight propellant, i. e., Hydrogen (H2) and then exhausted the extremely heated propellant through a thermodynamic nozzle to produce thrust. A propellant efficiency parameter of rocket engines is specific impulse (Isp) which represents the ratio of the thrust over the rate of propellant consumption. The difference of Isp makes over three times propellant savings of NTRs for a manned Mars mission compared to CRs. NTRs can also be configured to operate bimodally by converting the surplus nuclear energy to auxiliary electric power required for the operation of a spacecraft. Moreover, the concept and technology of NTRs are very simple, already proven, and safe. Thus, NTRs can be applied to various space missions such as solar system exploration, International Space Station (ISS) transport support, Near Earth Objects (NEOs) interception, etc. Nuclear propulsion is the most promising and viable option to achieve challenging deep space missions. Particularly, the attractions of a NTR include excellent thrust and propellant efficiency, bimodal capability, proven technology, and safe and reliable performance. The ROK has also begun the research for space nuclear systems as a volunteer of the international space race and a major world nuclear energy country. KANUTER is one of the advanced NTR engines currently under development at KAIST. This bimodal engine is operated in two modes of propulsion with 100 MWth power and

  11. Temporal changes of topsoil hydraulic conductivity studied by multiple-point tension disk infiltrometer

    Science.gov (United States)

    Klipa, Vladimir; Zumr, David; Snehota, Michal; Dohnal, Michal

    2015-04-01

    Hydraulic conductivity of cultivated soils is strongly affected by agrotechnical procedures, soil compaction, plant growth etc. This contribution is focused on series of measurement of topsoil unsaturated hydraulic conductivity using automated multipoint tension infiltrometer developed at CTU in Prague. The apparatus consists of two triplets of minidisk infiltrometers that are supported by a light aluminum frame. Therefore it allows simultaneous measurement of six tension infiltrations at two different pressure heads. Experiments were conducted at the experimental agricultural catchment Nučice (Central Bohemia, Czech Republic) as a part of the broader research of rainfall-runoff and soil erosion processes. The soil in the catchment is classified as Cambisol with texture that is ranging from loam to clay loam and is conservatively tilled. Series of ten infiltration campaigns (56 individual infiltration experiments) were carried out on a single experimental plot during period of two years. Dataset involves measurement under various agricultural activities and crop phenophases. The hydraulic conductivities were determined using extended semiempirical estimation procedure of Zhang. Additionally, large undisturbed soil samples were analyzed with use of X-ray computed tomography to assess the soil structure morphology in detail. Results show that unsaturated hydraulic conductivity was the lowest in early spring and did increase at beginning of summer. Unsaturated soil hydraulic conductivity was higher when the soil bulk density was high. During the summer and autumn the unsaturated hydraulic conductivity remained relatively unchanged. The impact of agricultural procedures was not apparent in the dataset.. The study has been supported by the Czech Science Foundation Project No. 13-20388P and by CTU in Prague funding via Student's Grant Competition SGS No. SGS14/131/OHK1/2T/11. The MultiDisk infiltrometer was developed within the framework of the project supported by the

  12. HYDRAULICS, LOUISA COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydraulic data include spatial datasets and data tables necessary for documenting the hydraulic analysis for estimating flood stages for a flood insurance study. It...

  13. A Parametric Study on the Thermal Hydraulic Design for an Annular Fuel Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Shin, C. H.; Seo, K. W.; Chun, T. H. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2008-10-15

    Recently, MIT proposed an internally and externally cooled annular fuel for an advanced PWR which can endure a substantial power uprating. To apply this annular fuel in the conventional reactors such as OPR-1000, it is desirable to investigate its a structural compatibility for its reloading to operating PWR reactors of OPR-1000 as well as other compatibilities like the fuel to moderator ratio, amount of fissile material and coolant flow area. Conventional fuel assembly has a 16x16 solid rod array with four big guide tubes and one instrumentation tube. A 12x12 annular fuel assembly design which can meet the above compatibilities was proposed, which is structurally compatible with the existing internals of OPR-1000. Actually the advantage of an annular fuel comes from the fuel performance and thermal hydraulics. In the thermal hydraulic analysis, the mixing effect between the neighboring channels has to be carried out in a subchannel analysis. A subchannel analysis code, MATRA has been developed by KAERI. However, MATRA dose not have the capability to model both an internally and externally cooled annular fuel. A subchannel code, MATRA-AF which can be coupled to MATRA and can calculate the coolant flow distribution and heat transfer fraction in the internal and external subchannels has been developed. In this paper, the characteristics and the verification of the MATRA-AF are described. The effects of the thermal hydraulic parameters are estimated through a single fuel assembly.

  14. A Parametric Study on the Thermal Hydraulic Design for an Annular Fuel Assembly

    International Nuclear Information System (INIS)

    Recently, MIT proposed an internally and externally cooled annular fuel for an advanced PWR which can endure a substantial power uprating. To apply this annular fuel in the conventional reactors such as OPR-1000, it is desirable to investigate its a structural compatibility for its reloading to operating PWR reactors of OPR-1000 as well as other compatibilities like the fuel to moderator ratio, amount of fissile material and coolant flow area. Conventional fuel assembly has a 16x16 solid rod array with four big guide tubes and one instrumentation tube. A 12x12 annular fuel assembly design which can meet the above compatibilities was proposed, which is structurally compatible with the existing internals of OPR-1000. Actually the advantage of an annular fuel comes from the fuel performance and thermal hydraulics. In the thermal hydraulic analysis, the mixing effect between the neighboring channels has to be carried out in a subchannel analysis. A subchannel analysis code, MATRA has been developed by KAERI. However, MATRA dose not have the capability to model both an internally and externally cooled annular fuel. A subchannel code, MATRA-AF which can be coupled to MATRA and can calculate the coolant flow distribution and heat transfer fraction in the internal and external subchannels has been developed. In this paper, the characteristics and the verification of the MATRA-AF are described. The effects of the thermal hydraulic parameters are estimated through a single fuel assembly

  15. Final Plan to Study the Potential Impacts of Hydraulic Fracturing on Drinking Water Resources (02-24-2012)

    Science.gov (United States)

    The overall purpose of this study is to elucidate the relationship, if any, between hydraulic fracturing and drinking water resources. More specifically, the study has been designed to assess the potential impacts of hydraulic fracturing on drinking water resources and to identif...

  16. Effect of biofilm on soil hydraulic properties: laboratory studies using xanthan as surrogate

    Science.gov (United States)

    Rosenkranz, H.; Iden, S. C.; Durner, W.

    2012-04-01

    Many soil bacteria produce extracellular polymeric substances (EPS) in which they are embedded while residing in the porous matrix. EPS are often attached as a biofilm to both the bacteria cell and the soil particles. As a consequence, their influence on water flow through variably saturated porous media often cannot be neglected. While the influence of attached microbial biomass and EPS on saturated water flow has been studied extensively, its investigation for unsaturated flow in soils has found significantly less attention. The objective of this study was the quantification of the effect of biofilms on the unsaturated soil hydraulic properties. We determined the soil water retention and unsaturated hydraulic conductivity functions of biofilm-affected soils by using xanthan as an EPS surrogate. Evaporation experiments were conducted on two sandy soil materials. The amount of added xanthan was varied in 6 stages from zero to 0.25 %. Additional measurements of soil water retention using the dewpoint method closed the remaining gap from the evaporation method to air-dryness. The experimental data were evaluated by the simplified evaporation method of Schindler. The results show that the unsaturated hydraulic conductivity is reduced markedly by added xanthan and the shape of the soil water retention curve is alterated significantly for all stages of xanthan addition. The reduction in hydraulic conductivity is high enough to fully suppress stage-one evaporation for xanthan-sand mixtures. The water-holding capacity of the xanthan and the alteration of the effective pore size distribution explain these results.

  17. Stability boundary calculation of thermal-hydraulic channels with RAMONA5, ATHLET and a reduced order model. A comparative study

    International Nuclear Information System (INIS)

    In the framework of the design study comprehensive system code analyses are performed with ATHLET and RAMONA. RAMONA is used in the current analysis because it has a broad validation basis for stability and transient analysis. On the other hand ATHLET has some advantages compared to RAMONA (free geometry and nodalization definition), which will be important to model and analyse the above mentioned test facility. One objective is to predict and confirm the operating conditions and transient behaviour for different facility designs. Thereby one aspect is the prediction of the thermal-hydraulic conditions at which self sustained density wave oscillations (ssDWOs) may occur under constant pressure drop boundary conditions. This paper is devoted to the latter investigation, only. In particular, we will discuss the question under which conditions the results of the measurement and simulation of the ssDWO onset are comparable to each other using the system codes ATHLET and RAMONA and, beside, an advanced reduced thermal-hydraulic model (TH-ROM). It will be shown why a precise measurement of the steady state axial profiles (void fraction, velocity of the liquid and gas phases and the axial pressure drop distribution) is of paramount importance in the scope of the present comparative study. (orig.)

  18. Stability boundary calculation of thermal-hydraulic channels with RAMONA5, ATHLET and a reduced order model. A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Jobst, Matthias; Lange, Carsten; Hennig, Dieter; Hurtado, Antonio [Technische Univ. Dresden (Germany). Professur fuer Wasserstoff- und Kernenergietechnik

    2013-07-01

    In the framework of the design study comprehensive system code analyses are performed with ATHLET and RAMONA. RAMONA is used in the current analysis because it has a broad validation basis for stability and transient analysis. On the other hand ATHLET has some advantages compared to RAMONA (free geometry and nodalization definition), which will be important to model and analyse the above mentioned test facility. One objective is to predict and confirm the operating conditions and transient behaviour for different facility designs. Thereby one aspect is the prediction of the thermal-hydraulic conditions at which self sustained density wave oscillations (ssDWOs) may occur under constant pressure drop boundary conditions. This paper is devoted to the latter investigation, only. In particular, we will discuss the question under which conditions the results of the measurement and simulation of the ssDWO onset are comparable to each other using the system codes ATHLET and RAMONA and, beside, an advanced reduced thermal-hydraulic model (TH-ROM). It will be shown why a precise measurement of the steady state axial profiles (void fraction, velocity of the liquid and gas phases and the axial pressure drop distribution) is of paramount importance in the scope of the present comparative study. (orig.)

  19. Consideration of a design optimization method for advanced nuclear power plant thermal-hydraulic components

    International Nuclear Information System (INIS)

    In order to meet the global energy demand and also mitigate climate change, we anticipate a significant resurgence of nuclear power in the next 50 years. Globally, Generation III plants (ABWR) have been built; Gen' III+ plants (EPR, AP1000 others) are anticipated in the near term. The U.S. DOE and Japan are respectively pursuing the NGNP and MSFR. There is renewed interest in closing the fuel cycle and gradually introducing the fast reactor into the LWR-dominated global fleet. In order to meet Generation IV criteria, i.e. thermal efficiency, inherent safety, proliferation resistance and economic competitiveness, plant and energy conversion system engineering design have to increasingly meet strict design criteria with reduced margin for reliable safety and uncertainties. Here, we considered a design optimization approach using an anticipated NGNP thermal system component as a Case Study. A systematic, efficient methodology is needed to reduce time consuming trial-and-error and computationally-intensive analyses. We thus developed a design optimization method linking three elements; that is, benchmarked CFD used as a 'design tool', artificial neural networks (ANN) to accommodate non-linear system behavior and enhancement of the 'design space', and finally, response surface methodology (RSM) to optimize the design solution with targeted constraints. The paper presents the methodology including guiding principles, an integration of CFD into design theory and practice, consideration of system non-linearities (such as fluctuating operating conditions) and systematic enhancement of the design space via application of ANN, and a stochastic optimization approach (RSM) with targeted constraints. Results from a Case Study optimizing the printed circuit heat exchanger for the NGNP energy conversion system will be presented. (author)

  20. Assimilating SAR-derived water level data into a hydraulic model: a case study

    Directory of Open Access Journals (Sweden)

    L. Giustarini

    2011-02-01

    Full Text Available Satellite-based active microwave sensors not only provide synoptic overviews of flooded areas, but also offer an effective way to estimate spatially distributed river water levels. If rapidly produced and processed, these data can be used for updating hydraulic models in near real-time. The usefulness of such approaches with real event data sets provided by currently existing sensors has yet to be demonstrated. In this case study, a Particle Filter-based assimilation scheme is used to integrate ERS-2 SAR and ENVISAT ASAR-derived water level data into a one-dimensional (1-D hydraulic model of the Alzette River. Two variants of the Particle Filter assimilation scheme are proposed with a global and local particle weighting procedure. The first option finds the best water stage line across all cross sections, while the second option finds the best solution at individual cross sections. The variant that is to be preferred depends on the level of confidence that is attributed to the observations or to the model. The results show that the Particle Filter-based assimilation of remote sensing-derived water elevation data provides a significant reduction to the model forecast uncertainty. Moreover, it is shown that the periodical updating of hydraulic models through the proposed assimilation scheme leads to an improvement of model predictions over several time steps. However, the performance of the assimilation depends on the skill of the hydraulic model and the quality of the observation data.

  1. Assimilating SAR-derived water level data into a hydraulic model: a case study

    Directory of Open Access Journals (Sweden)

    L. Giustarini

    2011-07-01

    Full Text Available Satellite-based active microwave sensors not only provide synoptic overviews of flooded areas, but also offer an effective way to estimate spatially distributed river water levels. If rapidly produced and processed, these data can be used for updating hydraulic models in near real-time. The usefulness of such approaches with real event data sets provided by currently existing sensors has yet to be demonstrated. In this case study, a Particle Filter-based assimilation scheme is used to integrate ERS-2 SAR and ENVISAT ASAR-derived water level data into a one-dimensional (1-D hydraulic model of the Alzette River. Two variants of the Particle Filter assimilation scheme are proposed with a global and local particle weighting procedure. The first option finds the best water stage line across all cross sections, while the second option finds the best solution at individual cross sections. The variant that is to be preferred depends on the level of confidence that is attributed to the observations or to the model. The results show that the Particle Filter-based assimilation of remote sensing-derived water elevation data provides a significant reduction in the uncertainty at the analysis step. Moreover, it is shown that the periodical updating of hydraulic models through the proposed assimilation scheme leads to an improvement of model predictions over several time steps. However, the performance of the assimilation depends on the skill of the hydraulic model and the quality of the observation data.

  2. MAAP thermal-hydraulic qualification sensitivity study results

    International Nuclear Information System (INIS)

    Several sensitivity studies have been performed with both the boiling water reactor (BWR) and pressurized water reactor (PWR) modular accident analysis program (MAAP) codes to test the important phenomena previously identified. These phenomena were listed as critical flow, level tracking, flashing, condensation, boiling and critical heat flux. This paper will summarize the study and provide insights into the findings from the study. For PWRs, Catawba was chosen as the reference plant. For BWRs, Peach Bottom was chosen as the reference plant. A series of studies were performed which encompass all of the phenomena of interest. The paper summarizes the relationship of the studies to the important phenomena. The first study varied the break area specifically to examine uncertainties in the critical flow model. In the process however, this affected a sensitivity to level tracking and flashing in the PWR case where the system depressurizes to saturation, and to level tracking and boiling in the BWR case where the system stays near the SRV setpoint pressure. Similarly, the primary phenomena investigated for each of the sensitivity studies is listed with the resulting secondary effects which are important to the variation considered

  3. NATO Advanced Study Institute on Advances in Chemical Reaction Dynamics

    CERN Document Server

    Capellos, Christos

    1986-01-01

    This book contains the formal lectures and contributed papers presented at the NATO Advanced Study Institute on. the Advances in Chemical Reaction Dynamics. The meeting convened at the city of Iraklion, Crete, Greece on 25 August 1985 and continued to 7 September 1985. The material presented describes the fundamental and recent advances in experimental and theoretical aspects of, reaction dynamics. A large section is devoted to electronically excited states, ionic species, and free radicals, relevant to chemical sys­ tems. In addition recent advances in gas phase polymerization, formation of clusters, and energy release processes in energetic materials were presented. Selected papers deal with topics such as the dynamics of electric field effects in low polar solutions, high electric field perturbations and relaxation of dipole equilibria, correlation in picosecond/laser pulse scattering, and applications to fast reaction dynamics. Picosecond transient Raman spectroscopy which has been used for the elucidati...

  4. Elastic-plastic solution and experimental study on critical water pressure inducing hydraulic fracturing in soil

    Institute of Scientific and Technical Information of China (English)

    朱俊高; 吉恩跃; 温彦锋; 张辉

    2015-01-01

    It is widely believed that hydraulic fracturing will occur in the clay core of an earth-rockfill dam if the water pressure in the core increases to levels that are high enough to allow a fracture to form. An elastic-plastic solution to critical water pressure inducing hydraulic fracturing(fracture initiation pressure) in soil is derived based on Mohr-Coulomb shear failure criterion and the theory of cavity expansion. In order to verify the applicability of the criteria presented and study the relations among fracture initiation pressure, tensile strength and stress state of soil, laboratory tests are performed on compacted cuboid specimens by true triaxial apparatus. According to the test results, the cracks of hydraulic fracturing existed perpendicular to the minor principal stress plane. The hydraulic fracturing pressure pf increases with the increase of dry density of specimen, pf shows good linear relationship with σ2 and σ3. The prediction from presented equation is compared with test results and other three predictions, of which two are tensile failure(TS) criterion, and the other is Mohr-Coulomb(M-C) criterion. The presented solution is verified, and the other three approaches for pf are evaluated. The comparison indicates that the predicted values from the presented equations agree well with the test values for specimens of low dry density, and the error of the prediction is larger for those of high dry density, especially in lower minor stress states. The predicted average relative error of absolute value Ra from TS1 criterion is 13.3% for all specimens of different dry densities, and each prediction is lower than the test data. On the contrary, most of the predicted values from M-C criterion are greater than the test data, but the average relative error from the presented equation is the minimum. Considering the safety of soil works, an equation from TS1 criterion is suggested to evaluate the occurrence of hydraulic fracturing in earth-rockfill dam

  5. Elastic-plastic solution and experimental study on critical water pressure inducing hydraulic fracturing in soil

    Institute of Scientific and Technical Information of China (English)

    朱俊高; 吉恩跃; 温彦锋; 张辉

    2015-01-01

    It is widely believed that hydraulic fracturing will occur in the clay core of an earth-rockfill dam if the water pressure in the core increases to levels that are high enough to allow a fracture to form. An elastic-plastic solution to critical water pressure inducing hydraulic fracturing (fracture initiation pressure) in soil is derived based on Mohr-Coulomb shear failure criterion and the theory of cavity expansion. In order to verify the applicability of the criteria presented and study the relations among fracture initiation pressure, tensile strength and stress state of soil, laboratory tests are performed on compacted cuboid specimens by true triaxial apparatus. According to the test results, the cracks of hydraulic fracturing existed perpendicular to the minor principal stress plane. The hydraulic fracturing pressurepf increases with the increase of dry density of specimen,pfshows good linear relationship withs2 ands3. The prediction from presented equation is compared with test results and other three predictions, of which two are tensile failure (TS) criterion, and the other is Mohr-Coulomb (M-C) criterion. The presented solution is verified, and the other three approaches forpf are evaluated. The comparison indicates that the predicted values from the presented equations agree well with the test values for specimens of low dry density, and the error of the prediction is larger for those of high dry density, especially in lower minor stress states. The predicted average relative error of absolute valueRa from TS1 criterion is 13.3% for all specimens of different dry densities, and each prediction is lower than the test data. On the contrary, most of the predicted values from M-C criterion are greater than the test data, but the average relative error from the presented equation is the minimum. Considering the safety of soil works, an equation from TS1 criterion is suggested to evaluate the occurrence of hydraulic fracturing in earth-rockfill dam designing.

  6. A Study on the Pressure Relief Scope and the Stress Variation of Hydraulic Flushing Borehole

    Directory of Open Access Journals (Sweden)

    C. F.Wei

    2014-01-01

    Full Text Available To study the variation of the pressure relief scope and the stress around hydraulic flushing borehole, the theory of coalrock damage was utilized to distinguish the interaction area of water-jet and coal-rock into the coal-rock crushing area, the water-jet pressure stagnation area, the transition area and the original stress recovery area of coal-rock. Based on the actual occurrence conditions of the coal seam, the pressure variation and relief scope around the hydraulic flushing borehole were analyzed and simulated by RFPA2D-Flow software. The results showed that a relief area with the radius of 5.0 ~ 6.0 m around the borehole formed due to the hydraulic flushing with the pressure relief of 0.038 ~ 6.545 MPa, and the maximum principal stress is 15.85 MPa with a distance of 6.8 m from the inspected hole where stress concentration appeared. After hydraulic flushing test, the diameter (441.8 ~ 1171.6 mm of the hole which can be an expression of coal crushing area size, was calculated based on the examination of the coal amount through the trial process, and it can be drawn that the pressure relief area must be larger than that of the coal-rock crushing area. Meanwhile, the measured pressures relief range(5.96 ~ 6.62 m is basically consistent with the numerical simulation result (5.0 ~ 6.0 m which verified the accuracy of the simulation analysis, according to the distance from the inspection drilling to the hydraulic flushing borehole and the decreased degree of the gas content in the inspection hole by the way of Gas Content.

  7. Soil water balance scenario studies using predicted soil hydraulic parameters

    NARCIS (Netherlands)

    Nemes, A.; Wösten, J.H.M.; Bouma, J.; Várallyay, G.

    2006-01-01

    Pedotransfer functions (PTFs) have become a topic drawing increasing interest within the field of soil and environmental research because they can provide important soil physical data at relatively low cost. Few studies, however, explore which contributions PTFs can make to land-use planning, in ter

  8. Hydraulic studies of in-situ permeable reactive barriers

    International Nuclear Information System (INIS)

    Groundwater flow velocity is a critical parameter in evaluating the field performance of in-situ permeable reactive barriers. Laboratory column tests indicate that bromide is a suitable studies involving granular iron. Conservative tracer tests conservative tracer for use in field tracer studies have been conducted to determine groundwater velocity and flow patterns through pilot-scale funnel-and-gate trials involving the EnviroMetal Process. Other methods of measuring in-situ velocities have also been evaluated. Once accurate groundwater flow velocities are known and concentrations of VOCs are measured, field degradation rates can be calculated. Both parameters are necessary for the design and costing of full-scale treatment systems

  9. Thermal hydraulic study of a corium molten pool

    International Nuclear Information System (INIS)

    The thermohydraulic behaviour of a mass of molten core is investigated, in the frame of PWR severe accidents studies. The corium may be located in the vessel lower head or in an external core-catcher. It is assumed to be present in the container instantaneously. Its motion is described by one velocity field. It may be homogeneous or made of two stratified fluids. The residual power is assumed to be constant and uniform in the UO2 phase. The radiative losses and the external water-cooling are taken into account. The thermal resistance of a peripheral crust is considered. The influence of the crust on the pool geometry may be studied. The wall behaviour is analysed by a conduction calculation. The interest of a sacrificial layer is underlined, so as the necessity of a multicomponent multiphase model to study the behaviour of a core catcher. It is also concluded that some experiments are needed for code validation about volume heated natural convection and multiphase flows. (author). 14 figs., 3 refs

  10. Study on hydraulic performance of φ10 mm centrifugal extractor

    International Nuclear Information System (INIS)

    For applying φ10 mm centrifugal extractor to study on the back-extraction section of plutonium purification cycle in Purex process, the characteristics such as the entrainment state of the two-phase exit liquid, the volume of the liquid in both the annular space and the rotor were studied when the rotor speed was changed, with the two- phase flow ratio (A : O) 1 : 4 and the heavy phase weir diameter 6.4 mm, 6.6 mm and 6.8 mm, respectively. The results show that the centrifugal extractor has a stable operational state when the total flow is less than 9.0 mL/min and the rotor speed is greater than 4000 r/min. There is no entrainment in the liquid two-phase exit. The liquid volumes in the annular space and the rotor are about 0.7 mL and 2.2 mL, respectively. The contact time of two-phase can be calculated by relating the total flow. (authors)

  11. Coupled Numerical Study of Turbidity Currents, Internal Hydraulic Jump and Morphological Signatures

    Science.gov (United States)

    Hu, P.; Cao, Z.; He, Z.; Gareth, P.

    2013-12-01

    Abstract: The last two decades have seen intensive experimental and numerical studies of the occurrence condition of internal hydraulic jump in turbidity currents and the induced morphological signatures (Garcia and Parker 1989; Kostic and Parker 2006). Yet there are two critical issues that remain insufficiently or inappropriately addressed. First, depositional turbidity currents are imposed on steep slopes in both flume experiments and numerical cases, exclusively based on a configuration consisting of an upstream sloping portion and a downstream horizontal portion linked by a slope break. This appears physically counterintuitive as steep slope should favour self-accelerating erosional turbidity currents (Parker et al. 1986). The second issue concerns the numerical studies. There exist significant interactions among the current, sediment transport and bed topography. Due to the slope break in bed, the current may experience an internal hydraulic jump, leaving morphological signatures on the bed, which in turn affects the current evolution. Nevertheless, simplified decoupled models are exclusively employed in previous numerical investigations, in which the interactions are either partly or completely ignored without sufficient justification. The present paper aims to address the above-mentioned two issues relevant to the occurrence condition of the internal hydraulic jump and the induced morphological signatures. A recently developed well-balanced coupled numerical model for turbidity currents (Hu et al. 2012) is applied. In contrast to previous studies, erosional turbidity currents will be imposed at the upstream boundary, which is much more typical of the field. The effects of sediment size, bed slope decrease, and upstream and downstream boundary conditions are revealed in detail. In addition, the evolution of turbidity currents over a bed characterized by gradual decrease in slope is also discussed. References Garcia, M. H., and Parker, G. (1989). Experiments

  12. Mapping Uncertainties – A case study on a hydraulic model of the river Voxnan.

    OpenAIRE

    Andersson, Sara

    2015-01-01

    This master thesis gives an account for the numerous uncertainties that prevail one-dimensional hydraulic models and flood inundation maps, as well as suitable assessment methods for different types of uncertainties. A conducted uncertainty assessment on the river Voxnan in Sweden has been performed. The case study included the calibra-tion uncertainty in the spatially varying roughness coefficient and the boundary condi-tion uncertainty in the magnitude of a 100-year flood, in present and fu...

  13. Hydraulic model calibration for extreme floods in bedrock-confined channels: case study from northern Thailand

    Science.gov (United States)

    Kidson, R. L.; Richards, K. S.; Carling, P. A.

    2006-02-01

    Palaeoflood reconstructions based on stage evidence are typically conducted in data-poor field settings. Few opportunities exist to calibrate the hydraulic models used to estimate discharge from this evidence. Consequently, an important hydraulic model parameter, the roughness coefficient (e.g. Manning's n), is typically estimated by a range of approximate techniques, such as visual estimation and semi-empirical equations. These techniques contribute uncertainty to resulting discharge estimates, especially where the study reach exhibits sensitivity in the discharge-Manning's n relation. We study this uncertainty within a hydraulic model for a large flood of known discharge on the Mae Chaem River, northern Thailand. Comparison of the calibrated Manning's n with that obtained from semi-empirical equations indicates that these underestimate roughness. Substantial roughness elements in the extra-channel zone, inundated during large events, contribute significant additional sources of flow resistance that are captured neither by the semi-empirical equations, nor by existing models predicting stage-roughness variations. This bedrock channel exhibits a complex discharge-Manning's n relation, and reliable estimates of the former are dependent upon realistic assignment of the latter. Our study demonstrates that a large recent flood can provide a valuable opportunity to constrain this parameter, and this is illustrated when we model a palaeoflood event in the same reach, and subsequently examine the magnitude-return period consequences of discharge uncertainty within a flood frequency analysis, which contributes its own source of uncertainty.

  14. Neutron-kinetic and thermo-hydraulic uncertainties in the study of Kalinin-3 benchmark

    International Nuclear Information System (INIS)

    The effects of nuclear data covariance on important reactor parameters are investigated. The analyses are performed on the base of the OECD/NEA coolant transient Benchmark (K-3) on measured data at Kalinin-3 Nuclear Power Plant (NPP). For this purpose the GRS uncertainty and sensitivity software package XSUSA is applied to propagate uncertainties in nuclear data libraries to the full core coupled transient calculations. Moreover, based on the previous thermo-hydraulic studies a set of most important thermo-hydraulic parameters is chosen and added to the uncertain input vector. A statistically representative set of coupled ATHLET PARCS code steady state calculations is analyzed and both integral and local output quantities are compared with the measurements available in the benchmark. The work is a step forward in establishing a ''best-estimate calculations in combination with performing uncertainty analysis'' methodology for coupled full core calculations.

  15. Monitoring of an hydraulic structure affected by ASR: A case study

    International Nuclear Information System (INIS)

    Relevant and effective instruments and techniques must be selected for monitoring hydraulic structures affected by Alkali-Silica Reaction ('ASR'). A program aiming at assessing the condition of a hydraulic structure affected by ASR is presented in this paper. The structure has been exhibiting signs of ASR for more than 30 years and shows various levels of damage. The program encompassed different components, consisting of: (1) stress measurement, (2) evaluation of concrete condition by nondestructive methods without drilling (seismic tomography), (3) the evaluation of the mechanical, physical and petrographic properties of the concrete determined from cores recovered from full-length boreholes. The results of this case study suggest that ASR may generate relatively little damage in structures and that the concrete mechanical properties do not seem to be significantly affected despite high expansion levels measured in this structure. A major crack was localized with the seismic tomography. The monitoring program will be used to follow the development of ASR in the structure.

  16. Neutron-kinetic and thermo-hydraulic uncertainties in the study of Kalinin-3 benchmark

    Energy Technology Data Exchange (ETDEWEB)

    Pasichnyk, Ihor; Zwermann, Winfried; Velkov, Kiril [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH, Garching (Germany); Nikonov, Sergey [All-Russain Research Institute for NPP Operation (VNIIAES), Moscow (Russian Federation)

    2015-09-15

    The effects of nuclear data covariance on important reactor parameters are investigated. The analyses are performed on the base of the OECD/NEA coolant transient Benchmark (K-3) on measured data at Kalinin-3 Nuclear Power Plant (NPP). For this purpose the GRS uncertainty and sensitivity software package XSUSA is applied to propagate uncertainties in nuclear data libraries to the full core coupled transient calculations. Moreover, based on the previous thermo-hydraulic studies a set of most important thermo-hydraulic parameters is chosen and added to the uncertain input vector. A statistically representative set of coupled ATHLET PARCS code steady state calculations is analyzed and both integral and local output quantities are compared with the measurements available in the benchmark. The work is a step forward in establishing a ''best-estimate calculations in combination with performing uncertainty analysis'' methodology for coupled full core calculations.

  17. Study of heat treatment parameters for large-scale hydraulic steel gate track

    Directory of Open Access Journals (Sweden)

    Ping-zhou CAO

    2013-10-01

    Full Text Available In order to enhance external hardness and strength, a large-scale hydraulic gate track should go through heat treatment. The current design method of hydraulic gate wheels and tracks is based on Hertz contact linear elastic theory, and does not take into account the changes in mechanical properties of materials caused by heat treatment. In this study, the heat treatment parameters were designed and analyzed according to the bearing mechanisms of the wheel and track. The quenching process of the track was simulated by the ANSYS program, and the temperature variation, residual stress, and deformation were obtained and analyzed. The metallurgical structure field after heat treatment was predicted by the method based on time-temperature-transformation (TTT curves. The results show that the analysis method and designed track heat treatment process are feasible, and can provide a reference for practical projects.

  18. Contesting Technologies in the Networked Society: A Case Study of Hydraulic Fracturing and Shale Development

    Science.gov (United States)

    Hopke, Jill E.

    In this dissertation, I study the network structure and content of a transnational movement against hydraulic fracturing and shale development, Global Frackdown. I apply a relational perspective to the study of role of digital technologies in transnational political organizing. I examine the structure of the social movement through analysis of hyperlinking patterns and qualitative analysis of the content of the ties in one strand of the movement. I explicate three actor types: coordinator, broker, and hyper-local. This research intervenes in the paradigm that considers international actors as the key nodes to understanding transnational advocacy networks. I argue this focus on the international scale obscures the role of globally minded local groups in mediating global issues back to the hyper-local scale. While international NGOs play a coordinating role, local groups with a global worldview can connect transnational movements to the hyper-local scale by networking with groups that are too small to appear in a transnational network. I also examine the movement's messaging on the social media platform Twitter. Findings show that Global Frackdown tweeters engage in framing practices of: movement convergence and solidarity, declarative and targeted engagement, prefabricated messaging, and multilingual tweeting. The episodic, loosely-coordinated and often personalized, transnational framing practices of Global Frackdown tweeters support core organizers' goal of promoting the globalness of activism to ban fracking. Global Frackdown activists use Twitter as a tool to advance the movement and to bolster its moral authority, as well as to forge linkages between localized groups on a transnational scale. Lastly, I study the relative prominence of negative messaging about shale development in relation to pro-shale messaging on Twitter across five hashtags (#fracking, #globalfrackdown, #natgas, #shale, and #shalegas). I analyze the top actors tweeting using the #fracking

  19. NATO Advanced Study Institute on Advanced Physical Oceanographic Numerical Modelling

    CERN Document Server

    1986-01-01

    This book is a direct result of the NATO Advanced Study Institute held in Banyuls-sur-mer, France, June 1985. The Institute had the same title as this book. It was held at Laboratoire Arago. Eighty lecturers and students from almost all NATO countries attended. The purpose was to review the state of the art of physical oceanographic numerical modelling including the parameterization of physical processes. This book represents a cross-section of the lectures presented at the ASI. It covers elementary mathematical aspects through large scale practical aspects of ocean circulation calculations. It does not encompass every facet of the science of oceanographic modelling. We have, however, captured most of the essence of mesoscale and large-scale ocean modelling for blue water and shallow seas. There have been considerable advances in modelling coastal circulation which are not included. The methods section does not include important material on phase and group velocity errors, selection of grid structures, advanc...

  20. Studies and projections of hydraulic conductivity of Devonian Plavinu and Daugava carbonate aquifers in Latvia

    Science.gov (United States)

    Perkone, E.; Delina, A.; Saks, T.; Raga, B.; Jātnieks, J.; Klints, I.; Popovs, K.; Babre, A.; Bikše, J.; Kalvāns, A.; Retike, I.; Ukass, J.

    2012-04-01

    Carbonate aquifers show a very wide range of hydrogeological characteristics. Carbonate rock hydrogeology display two extremes: on one hand hydrogeological properties of the carbonates are governed by the pathways of the preferential groundwater flow typical in karstic regions, on the other - some carbonate aquifers behave almost like a homogeneous, isotropic, porous medium. Most lie between these extremes, but these case variations complicates the study of carbonate aquifer properties. In this study the results of the hydraulic conductivity in carbonate aquifers measurements, hydraulic conductivity correlation between sediments lithology and the aquifer surface depth and fractures research is presented. Upper Devonian Frasnian stage Pļaviņu and Daugava carbonate aquifers in the Latvian part of the Baltic basin is considered. The aim of this research is to elaborate characteristic hydraulic conductivity values for each aquifer based on existing data of the pumping test results and other aquifer properties. Pļaviņu and Daugava carbonate aquifers mainly consist of jointed dolomite with intermediate layers of dolomitic marlstone, limestone, clays and gypsum. These aquifers are prevalent in most of the study area, except Northern and South - Eastern parts of the territory. In geological structure Daugava aquifer lies above Pļaviņu aquifer. Daugava aquifer depth changes from 10 - 20 and even less meters in Eastern part to 250 - 300 m in South - West part of study area, but thickness varies from few meters to 30 m. Pļaviņu aquifer surface depth varies from 20 - 30 m, but in uplands surface depth reaches more than 120 m, in Eastern part to more than 300 m in South - West part of study area. Aquifer average thickness varies from 20 - 40 m, but in areas with buried valleys thickness can be less than 10 meters. Outcrops of these sediments are occurring in banks of largest rivers and in some areas aquifers are karstified. In studies of the carbonate aquifers it is

  1. An approach to the field study of hydraulic gradients in variable- salinity ground water

    Science.gov (United States)

    Hickey, J.J.

    1989-01-01

    A field study approach is proposed for reliably estimating hydraulic gradients in subregions within a region of variable-salinity ground water. It is based upon Hubbert's concept about the kind of density distributions that are required for ground water to have a potential. The approach consists of dividing a region of variable-salinity ground water into subregions with constant density, subregions with only vertical variations in density, and subregions with vertical and lateral variations in density before determining magnitude and direction of hydraulic gradients. The approach was applied to an unconfined coastal aquifer and also to a confined and layered coastal aquifer that is used for sub-surface injection. As the two applications show, the analysis of water levels and pressures from subregions with constant or approximately constant density and the analysis of pressures from subregions with only vertical variations in density provide simple and direct means for deducing the characteristics of hydraulic gradients within a region of variable-salinity ground water. -from Author

  2. Experimental identification and study of hydraulic resonance test rig with Francis turbine operating at partial load

    Science.gov (United States)

    Favrel, A.; Landry, C.; Müller, A.; Avellan, F.

    2012-11-01

    Resonance in hydraulic systems is characterized by pressure fluctuations of high amplitude which can lead to undesirable and dangerous effects, such as noise, vibration and structural failure. For a Francis turbine operating at partial load, the cavitating vortex rope developing at the outlet of the runner induces pressure fluctuations which can excite the hydraulic system resonance, leading to undesirable large torque and power fluctuations. At resonant operating points, the prediction of amplitude pressure fluctuations by hydro-acoustic models breaks down and gives unreliable results. A more detailed knowledge of the eigenmodes and a better understanding of phenomenon occurring at resonance could allow improving the hydro-acoustic models prediction.This paper presents an experimental identification of a resonance observed in a close-looped hydraulic system with a Francis turbine reduced scale model operating at partial load. The resonance is excited matching one of the test rig eigenfrequencies with the vortex rope precession frequency. At this point, the hydro-acoustic response of the test rig is studied more precisely and used finally to reproduce the shape of the excited eigenmode.

  3. Experimental study of thermal–hydraulic performance of cam-shaped tube bundle with staggered arrangement

    International Nuclear Information System (INIS)

    Highlights: • Thermal–hydraulic performance of a non-circular tube bundle has been investigated experimentally. • Tubes were mounted in staggered arrangement with two longitudinal pitch ratios 1.5 and 2. • Drag coefficient and Nusselt number of tubes in second row was measured. • Friction factor of this tube bundle is lower than circular tube bundle. • Thermal–hydraulic performance of this tube bundle is greater than circular tube bundle. - Abstract: Flow and heat transfer from cam-shaped tube bank in staggered arrangement is studied experimentally. Tubes were located in test section of an open loop wind tunnel with two longitudinal pitch ratios 1.5 and 2. Reynolds number varies in range of 27,000 ⩽ ReD ⩽ 42,500 and tubes surface temperature is between 78 and 85 °C. Results show that both drag coefficient and Nusselt number depends on position of tube in tube bank and Reynolds number. Tubes in the first column have maximum value of drag coefficient, while its Nusselt number is minimum compared to other tubes in tube bank. Moreover, pressure drop from this tube bank is about 92–93% lower than circular tube bank and as a result thermal–hydraulic performance of this tube bank is about 6 times greater than circular tube bank

  4. Experimental identification and study of hydraulic resonance test rig with Francis turbine operating at partial load

    International Nuclear Information System (INIS)

    Resonance in hydraulic systems is characterized by pressure fluctuations of high amplitude which can lead to undesirable and dangerous effects, such as noise, vibration and structural failure. For a Francis turbine operating at partial load, the cavitating vortex rope developing at the outlet of the runner induces pressure fluctuations which can excite the hydraulic system resonance, leading to undesirable large torque and power fluctuations. At resonant operating points, the prediction of amplitude pressure fluctuations by hydro-acoustic models breaks down and gives unreliable results. A more detailed knowledge of the eigenmodes and a better understanding of phenomenon occurring at resonance could allow improving the hydro-acoustic models prediction.This paper presents an experimental identification of a resonance observed in a close-looped hydraulic system with a Francis turbine reduced scale model operating at partial load. The resonance is excited matching one of the test rig eigenfrequencies with the vortex rope precession frequency. At this point, the hydro-acoustic response of the test rig is studied more precisely and used finally to reproduce the shape of the excited eigenmode.

  5. Centrifugal slurry pump wear and hydraulic studies. Phase II report. Experimental studies

    Energy Technology Data Exchange (ETDEWEB)

    Mistry, D.; Cooper, P.; Biswas, C.; Sloteman, D.; Onuschak, A.

    1983-01-01

    This report describes the work performed by Ingersoll-Rand Research, Inc., under Phase II, Experimental Studies for the contract entitled, Centrifugal Slurry Pump Wear and Hydraulic Studies. This work was carried out for the US Department of Energy under Contract No. DE-AC-82PC50035. The basic development approach pursued this phase is presented, followed by a discussion on wear relationships. The analysis, which resulted in the development of a mathematical wear model relating pump life to some of the key design and operating parameters, is presented. The results, observations, and conclusions of the experimental investigation on small scale pumps that led to the selected design features for the prototype pump are discussed. The material investigation was performed at IRRI, ORNL and Battelle. The rationale for selecting the materials for testing, the test methods and apparatus used, and the results obtained are presented followed by a discussion on materials for a prototype pump. In addition, the prototype pump test facility description, as well as the related design and equipment details, are presented. 20 references, 53 figures, 13 tables.

  6. Development of numerical procedure for thermal hydraulic design of nuclear reactors with advanced two-fluid model (1). Improvement of numerical stability of advanced two-fluid model

    International Nuclear Information System (INIS)

    Two-fluid model is still useful to simulate two-phase flow in large domain such as rod bundles. However, two-fluid model include a lot of constitutive equations, and the two-fluid model has problems that the results of analyses depend on accuracy of constitutive equations. To solve these problems, we have been developing an advanced two-fluid model. In this model, an interface tracking method is combined with the two-fluid model to predict large interface structure behavior without any constitutive equations, and constitutive equations to evaluate the effects of small bubbles or droplets are only required. In this study, we modified the advanced two-fluid model to improve the stability of the numerical simulation and reduce the computational time. In this paper, we describe the modification performed in this study and the numerical results of two-phase flow in various flow conditions are shown. (author)

  7. Effect of biocrust: study of mechanical and hydraulic properties and erodibility

    Science.gov (United States)

    Slavík, Martin; Bruthans, Jiří; Schweigstillová, Jana

    2016-04-01

    It is well-known that lichens and other organisms forming crust on soil or rock surface play important role in weathering but may also protect underlying material from fast erosion. So far, there have been only few measurements comparing mechanical or hydraulic properties of biocrust with its subsurface on locked sand and friable sandstones, so the overall effect of the biocrust is not well-understood. Objective of our study is to quantify the effect of the biocrust on mechanical and hydraulic properties of friable sandstone and locked sand of Cretaceous age in six different localities with varying aspect and inclination and age of exposure in sandpit Strelec (Czech Rep.). On the artificial exposures, biocrust developed within last 10-30 years. Beside measurements of mechanical and hydraulic properties, SEM and mercury intrusion porosimetry in crust and subsurface was performed. Drilling resistance technique was found an excellent method to distinguish the biocrust from its subsurface (~3 mm thick biocrust has up to 12 times higher drilling resistance than underlying material). Surface zone with the biocrust has 3 - 25 times higher tensile strength than the subsurface material (1 - 25 kPa). In comparison with the subsurface, the biocrust is considerably less erodible (based on water jet testing). Biocrust saturated hydraulic conductivity is 15 - 240 times lower than the subsurface (6*10 -5 - 1*10 -4 m/s) and its permeability for water vapor is 4 - 9 times lower than subsurface. Presence of the biocrust slows down capillary absorption of water 4 - 25 times. The biocrust is thus forming firm surface which protects underlying material from rain and flowing water erosion and which considerably modifies its hydraulic properties. Material with crust exposed to calcination, leaching by concentrated peroxide and experiments with zymoliase enzyme strongly indicate that major contribution to crust hardening is provided by organic matter. Based on DNA sequencing the crust is

  8. Experimental study of hydraulic transport of large particles in horizontal pipes

    OpenAIRE

    Ravelet, Florent; Bakir, Farid; Khelladi, Sofiane; Rey, Robert

    2013-01-01

    This article presents an experimental study of the hydraulic transport of very large solid particles (above 5 mm) in an horizontal pipe. Two specific masses are used for the solids. The solids are spheres that are large with respect to the diameter of the pipe (5, 10 and 15%) or real stones of arbitrary shapes but constant specific mass and a size distribution similar to the tested spherical beads. Finally, mixtures of size and / or specific mass are studied. The regimes are characterized wit...

  9. Parameter sensitivity study of boiling and two-phase flow models in computational thermal hydraulics

    International Nuclear Information System (INIS)

    This work presents a sensitivity study of boiling and two phase flow models for thermal hydraulics simulations in nuclear reactors. The study quantifies sources of uncertainty and error in these simulations by computing global sensitivities of figures of merit, or outputs, to model parameters, inputs, and mesh resolution. Results are obtained for the DEBORA benchmark problem of boiling in a channel driven by a heated wall section. Scalar outputs of interest are average wall temperature, integrated cross-sectional void fraction, and pressure drop in the channel. Sensitivities are computed with respect to both individual heat fluxes and to the parameters in the models for these heat fluxes. (author)

  10. Hydraulic conductivity of sandstones in the Baltic Basin - a comparative study of pumping tests and grain size distribution

    Science.gov (United States)

    Perkone, E.; Bikše, J.; Jātnieks, J.; Klints, I.; Delina, A.; Saks, T.; Raga, B.; Retike, I.

    2012-04-01

    Aquifer fluid conductivity properties describe ability of sediments to transmit groundwater, and consequently govern the groundwater flow. Studies and knowledge of hydraulic conductivity (K), transmissivity and storativity for the particular aquifer is of great importance for hydrogeological problem solving process. This study presents the results of the comparative study between hydraulic conductivity, grain size distribution, sediments lithology of the lower Devonian Emsian stage, middle Devonian Eifelian and Givetian stage, upper Devonian Frasnian stage, and Cambrian clastic sediments in the central part of the Baltic Basin. The aim of this study was to find characteristic hydraulic conductivity values for each aquifer based on aquifer grain size distribution and lithology on the one hand and pumping test results one the other. For the calculation of the hydraulic conductivity one has to take into account not only grain size distribution but effective porosity, temperature and kinematic viscosity of the fluid as well, which are lacking in this study. Pumping test results provide a range of at least two orders of hydraulic conductivity values for each aquifer. To characterize the typical values for each aquifer and further subdivide each aquifer into regions of different hydraulic conductivities, pumping test results were correlated with grain size distribution. As a limiting factor for the hydraulic conductivity in the sandstones the fraction of the fine particles with the size less than 0.05 mm were chosen. The correlation of hydraulic conductivity and grain size distribution was carried out by comparing the Social Fund project No. 2009/0212/1DP/1.1.1.2.0/09/APIA/VIAA/060

  11. Experimental study on self-healing of bentonite/sand mixtures and its impact on hydraulic permeability

    International Nuclear Information System (INIS)

    The effects of gas permeation on the hydraulic permeability of bentonite/sand mixtures were studied experimentally by conducting permeability tests with various fluids and by microscopic observations. In these tests, hydraulic permeabilities were measured before and after helium gas was applied to permeate the mixtures. Although gas formed preferential migration paths through the mixtures, the imperviousness of the bentonite/sand mixtures to the tested fluids never deteriorated because the paths became filled by swelling bentonite on re-saturation

  12. Experimental study on self-healing of bentonite/sand mixtures in hydraulic permeability

    International Nuclear Information System (INIS)

    Effects of gas permeation on the impervious characteristics of bentonite/sand mixtures were studied experimentally by conducting permeability tests with various fluids and microscopic observations. In this test, hydraulic permeabilities were measured before/after helium gas was applied to permeate through the mixtures. It was found that gas formed preferential paths to migrate through the mixtures, and that the bentonite/sand mixtures never deteriorated in impervious capacity because the paths were-filled with swelling bentonite in re-saturation. (author)

  13. Study on Wireless Network Communication in Stage Hydraulic Monitoring System Based on Internet of Things

    OpenAIRE

    Yue Dong; Hui Ren; Jianghui Dong; Liping Wang

    2015-01-01

    A novel stage hydraulic monitoring system based on Internet of Things (IoT) is proposed in this paper. Compared with the traditional wired system, the proposed system is a flexible working method and can save the cost. Furthermore, it has the low power consumption, high safety, and large scale network. The real-time pressure and flow data can be collected by using the nodes in ZigBee network. The fault detection and diagnosis process was used in this study, which was facilitated by measuring ...

  14. Application of Advanced Thermal Hydraulic TRACG Model to Preserve Operating Margins in BWRs at Extended Power Up-rate Conditions

    International Nuclear Information System (INIS)

    GE has developed TRACG, a customized BWR version of the TRAC model, for application to BWR analyses. This model was initially applied to special BWR challenges and for benchmarking the official simplified thermal-hydraulic design models. However, in past years extensive additional model development, qualification and application studies have been completed. This development has followed the CSAU methodology, where extensive model evaluation and qualification have been performed to demonstrate the applicability of the model and to quantify the uncertainty in the model parameters as well as in plant parameters and initial conditions. This has then been combined with a statistically based application methodology following the CSAU approach to generate tolerance limits for the critical safety and design parameters. This effort has resulted in application processes that have been reviewed and approved by the US NRC to enable routine application of the TRACG model to the design and licensing analyses and utilize the improved operating margin to optimize the fuel cycle design. These applications have been supported by development of programs that construct specific plant and problem base-decks that utilize BWR plant characteristics and system databases to standardize and streamline the application to several plants. The application of the TRACG model in Transient and LOCA analyses has assisted in allowing similar power peaking at higher power density conditions for BWRs. Also, the application of the TRACG model in Stability analyses has assisted in preserving the setpoints of stability monitoring systems to avoid margin loss for high power density applications. TRACG is being used for analysis of ATWS events. It has been used to support the development of emergency procedure guidelines, and it is currently being used to demonstrate that the suppression pool temperature limits can be met for up-rated conditions. Finally, the application of the TRACG model in Faulted Load

  15. Hydraulic modelling for flood mapping and prevention: the case study of Cerfone River

    Science.gov (United States)

    Di Francesco, Silvia; Venturi, Sara; Manciola, Piergiorgio

    2016-04-01

    The research focuses on the hydraulic risk evaluation and danger estimation for different extreme flood events, in order to correctly implement mitigation measures in an anthropized basin. The Cerfone River (Tuscany, Italy), due to the several floods that have affected the neighbouring villages in recent years, is selected as case of study. A finite volume numerical model that solves the shallow water equations all over the computational domain, was used to simulate the unsteady evolution of the maximum extent of flooded areas for different scenarios. The one - dimensional approach (still widespread in engineering projects) can be inaccurate in complex flows, which are often two or three dimensional and sometimes does not manage to capture the flood spatial extents in terms of flow depth and velocity. The use of a two-dimensional numerical model seems to be the suitable instrument in terms of computational efficiency and adequacy of results. In fact it overcomes the limits of a one-dimensional modeling in terms of prediction of hydraulic variables with a less computational effort respect to a full 3d model. An accurate modeling of the river basin leads to the evaluation of the present hydraulic risk. Structural and non- structural measures are then studied, simulated and compared in order to define the optimal risk reduction plan for the area of study. At this aim, different flooding scenarios were simulated through the 2D mathematical model: i) existing state of the river and floodplain areas; ii) design of a levee to protect the most vulnerable populated areas against the flooding risk; iii) use of off - stream detention basins that strongly amplify the lamination capacity of floodplains. All these scenarios were simulated for different return periods: 50, 100, 200 and 500 years. The inputs of the hydraulic models are obtained in accordance with the legislative requirement of Tuscany Region; in particular discharge hydrographs are evaluate through the ALTo

  16. Contribution to the study of thermal-hydraulic problems in nuclear reactors

    International Nuclear Information System (INIS)

    In nuclear reactors, whatever the type considered, Pressurized Water Water Reactors (PWRs), Fast Breeder reactors (FBRs)..., thermal-hydraulics, the science of fluid mechanics and thermal behaviour, plays an essential role, both in nominal operating and accidental conditions. Fluid can either be the primary fluid (liquid or gas) or a very specific fluid called corium, which, in case of severe accident, could result from core and environning structure melting. The work reported here represents a 20-year contribution to thermal-hydraulic issues which could occur in FBRs and PWRs. Working on these two types of reactors, both in nominal and severe accident situations, has allowed me to compare the problems and to realize the importance of communication between research teams. The evolution in the complexity of studied problems, unavoidable in order to reduce costs and significantly improve safety, has led me from numerical modelling of single-phase flow turbulence to high temperature real melt experiments. The difficulties encountered in understanding the observed phenomena and in increasing experimental databases for computer code qualification have often entailed my participation in specific measurement device developments or adaptations, in particular non-intrusive devices generally based on optical techniques. Being concerned about the end-use of this research work, I actively participated in 'in-situ' thermalhydraulic experiments in the FBRs: Phenix and Super-Phenix, of which I appreciated their undeniable scientific contribution. In my opinion, the thermal-hydraulic questions related to severe accidents are the most complex as they are at the cross-roads of several scientific specialities. Consequently, they require a multi-disciplinary approach and a continuous see-saw motion between experimentalists and modelling teams. After a brief description of the various problems encountered, the main ones are reported. Finally, the importance for research teams to

  17. Investigation of film boiling thermal hydraulics under FCI conditions. Results of a numerical study

    Energy Technology Data Exchange (ETDEWEB)

    Dinh, T.N.; Dinh, A.T.; Nourgaliev, R.R.; Sehgal, B.R. [Div. of Nuclear Power Safety Royal Inst. of Tech. (RIT), Brinellvaegen 60, 10044 Stockholm (Sweden)

    1998-01-01

    Film boiling on the surface of a high-temperature melt jet or of a melt particle is one of key phenomena governing the physics of fuel-coolant interactions (FCIs) which may occur during the course of a severe accident in a light water reactor (LWR). A number of experimental and analytical studies have been performed, in the past, to address film boiling heat transfer and the accompanying hydrodynamic aspects. Most of the experiments have, however, been performed for temperature and heat flux conditions, which are significantly lower than the prototypic conditions. For ex-vessel FCIs, high liquid subcooling can significantly affect the FCI thermal hydraulics. Presently, there are large uncertainties in predicting natural-convection film boiling of subcooled liquids on high-temperature surfaces. In this paper, research conducted at the Division of Nuclear Power Safety, Royal Institute of Technology (RIT/NPS), Stockholm, concerning film-boiling thermal hydraulics under FCI condition is presented. Notably, the focus is placed on the effects of (1) water subcooling, (2) high-temperature steam properties, (3) the radiation heat transfer and (4) mixing zone boiling dynamics, on the vapor film characteristics. Numerical investigations are performed using a novel CFD modeling concept named as the local-homogeneous-slip model (LHSM). Results of the analytical and numerical studies are discussed with respect to boiling dynamics under FCI conditions. (author)

  18. Dynamics of Model Hydraulic Fracturing Liquid Studied by Two-Dimensional Infrared Spectroscopy

    Science.gov (United States)

    Daley, Kim; Kubarych, Kevin J.

    2014-06-01

    The technique of two-dimensional infrared (2DIR) spectroscopy is used to expose the chemical dynamics of various concentrations of polymers and their monomers in heterogeneous mixtures. An environmentally relevant heterogeneous mixture, which inspires this study, is hydraulic fracturing liquid (HFL). Hydraulic fracking is a technique used to extract natural gas from shale deposits. HFL consists of mostly water, proppant (sand), an emulsifier (guar), and other chemicals specific to the drilling site. Utilizing a metal carbonyl as a probe, we observe the spectral dynamics of the polymer, guar, and its monomer, mannose, and compare the results to see how hydration dynamics change with varying concentration. Another polymer, Ficoll, and its monomer, sucrose, are also compared to see how polymer size affects hydration dynamics. The two results are as follows: (1) Guar experiences collective hydration at high concentrations, where as mannose experiences independent hydration; (2) no collective hydration is observed for Ficoll in the same concentration range as guar, possibly due to polymer shape and size. HFL experiences extremely high pressure during natural gas removal, so future studies will focus on how increased pressure affects the hydration dynamics of polymers and monomers.

  19. Thermal hydraulic parameter studies of heat exchanger for the TRIGA MARK II research reactor

    International Nuclear Information System (INIS)

    Thermal Hydraulic studies have being conducted at PUSPATI TRIGA Mark II (RTP) Nuclear Research Reactor. The purpose of this study is to determine the heat transfer characteristic and heat exchanger performance at difference reactor power. Fundamental concept and a plate type application of heat exchanger in RTP are presented in this study. A plate type heat exchanger is a device for RTP reactor cooling system built for efficient heat transfer from one fluid to another. The study involves the observation of inlet and outlet temperature profile, flow rate and pressure at the reactor pool and heat exchanger. The observed parameters are compared to basic engineering calculation and the output of the study has been beneficial to evaluate the performance of newly-installed plate type heat exchanger. (author)

  20. Experimental Study of a Small Scale Hydraulic System for Mechanical Wind Energy Conversion into Heat

    Directory of Open Access Journals (Sweden)

    Tadas Zdankus

    2016-07-01

    Full Text Available Significant potential for reducing thermal energy consumption in buildings of moderate and cold climate countries lies within wind energy utilisation. Unlike solar irradiation, character of wind speeds in Central and Northern Europe correspond to the actual thermal energy demand in buildings. However, mechanical wind energy undergoes transformation into electrical energy before being actually used as thermal energy in most wind energy applications. The study presented in this paper deals with hydraulic systems, designed for small-scale applications to eliminate the intermediate energy transformation as it converts mechanical wind energy into heat directly. The prototype unit containing a pump, flow control valve, oil tank and piping was developed and tested under laboratory conditions. Results of the experiments showed that the prototype system is highly efficient and adjustable to a broad wind velocity range by modifying the definite hydraulic system resistance. Development of such small-scale replicable units has the potential to promote “bottom-up” solutions for the transition to a zero carbon society.

  1. Forming-Precision-Driven Structure Design of Hydraulic Press:Methodology and Case Study

    Institute of Scientific and Technical Information of China (English)

    李艳聪; 张连洪; 何柏岩; 陈永亮; 张淳

    2015-01-01

    The structure stiffness of presses has great effects on the forming precision of workpieces, especially in near-net or net shape forming. Conventionally the stiffness specification of presses is empirically determined, re-sulting in poor designs with insufficient or over sufficient stiffness of press structures. In this paper, an approach for the structure design of hydraulic presses is proposed, which is forming-precision-driven and can make presses cost-effective by lightweight optimization. The approach consists of five steps:(1)the determination of the press stiff-ness specification in terms of the forming precision requirement of workpieces;(2)the conceptual design of the press structures according to the stiffness and workspace specifications, and the structure configuration of the press;(3)the prototype design of the press structures by equivalently converting the conceptual design to proto-types;(4)the selection of key structure parameters by sensitivity analysis of the prototype design; and(5)the opti-mization of the prototype design. The approach is demonstrated and validated through a case study of the structure design of a 100 MN hydraulic press.

  2. Study on Wireless Network Communication in Stage Hydraulic Monitoring System Based on Internet of Things

    Directory of Open Access Journals (Sweden)

    Yue Dong

    2015-01-01

    Full Text Available A novel stage hydraulic monitoring system based on Internet of Things (IoT is proposed in this paper. Compared with the traditional wired system, the proposed system is a flexible working method and can save the cost. Furthermore, it has the low power consumption, high safety, and large scale network. The real-time pressure and flow data can be collected by using the nodes in ZigBee network. The fault detection and diagnosis process was used in this study, which was facilitated by measuring pressure of flow. When the monitored data exceeds the normal range, some failure may occur in the stage hydraulic system. If any failure occurs in the circuit, the maintainers can be informed immediately, which can greatly improve maintenance efficiency, ensuring the failure to be eliminated in time. Meanwhile, we can take advantage of wireless sensor network (WSN to connect the multiple loops and then monitor the loops by using ZigBee technology, which greatly improves the efficiency of monitoring.

  3. Applied hydraulic transients

    CERN Document Server

    Chaudhry, M Hanif

    2014-01-01

    This book covers hydraulic transients in a comprehensive and systematic manner from introduction to advanced level and presents various methods of analysis for computer solution. The field of application of the book is very broad and diverse and covers areas such as hydroelectric projects, pumped storage schemes, water-supply systems, cooling-water systems, oil pipelines and industrial piping systems. Strong emphasis is given to practical applications, including several case studies, problems of applied nature, and design criteria. This will help design engineers and introduce students to real-life projects. This book also: ·         Presents modern methods of analysis suitable for computer analysis, such as the method of characteristics, explicit and implicit finite-difference methods and matrix methods ·         Includes case studies of actual projects ·         Provides extensive and complete treatment of governed hydraulic turbines ·         Presents design charts, desi...

  4. Advance in MEIC cooling studies

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yuhong [JLAB, Newport News, VA (United States); Derbenev, Ya. [JLAB, Newport News, VA (United States); Douglas, D. [JLAB, Newport News, VA (United States); Hutton, A. [JLAB, Newport News, VA (United States); Kimber, A. [JLAB, Newport News, VA (United States); Li, R. [JLAB, Newport News, VA (United States); Nissen, E. [JLAB, Newport News, VA (United States); Tennant, [JLAB, Newport News, VA (United States); Zhang, H. [JLAB, Newport News, VA (United States)

    2013-06-01

    Cooling of ion beams is essential for achieving a high luminosity for MEIC at Jefferson Lab. In this paper, we present the design concept of the electron cooling system for MEIC. In the design, two facilities are required for supporting a multi-staged cooling scheme; one is a 2 MeV DC cooler in the ion pre-booster; the other is a high electron energy (up to 55 MeV) ERL-circulator cooler in the collider ring. The simulation studies of beam dynamics in an ERL-circulator cooler are summarized and followed by a report on technology development for this cooler. We also discuss two proposed experiments for demonstrating high energy cooling with a bunched electron beam and the ERL-circulator cooler.

  5. Parametric study of the stability properties of a thermo hydraulic channel coupled to punctual kinetics

    International Nuclear Information System (INIS)

    The reason of decay is the indicator of stability usually used in the literature to evaluate stability of boiling water reactors, however, in the operation of this type of reactors is considered the length of boiling like an auxiliary parameter for the evaluation of stability. In this work its are studied the variation of these two indicators when modifying a given an operation parameter in a model of a thermo hydraulic channel coupled to punctual kinetics, maintaining all the other input constant variables. The parameters selected for study are the axial profile of power, the subcooling, the flow of coolant and the thermal power. The study is supplemented by means of real data of plant using the one Benchmark of Ringhals, and the results for the case of the ratio of decay its are compared with the decay reasons obtained by means of autoregression models of the local instrumentation of neutron flux. (Author)

  6. Hydraulic structures

    CERN Document Server

    Chen, Sheng-Hong

    2015-01-01

    This book discusses in detail the planning, design, construction and management of hydraulic structures, covering dams, spillways, tunnels, cut slopes, sluices, water intake and measuring works, ship locks and lifts, as well as fish ways. Particular attention is paid to considerations concerning the environment, hydrology, geology and materials etc. in the planning and design of hydraulic projects. It also considers the type selection, profile configuration, stress/stability calibration and engineering countermeasures, flood releasing arrangements and scouring protection, operation and maintenance etc. for a variety of specific hydraulic structures. The book is primarily intended for engineers, undergraduate and graduate students in the field of civil and hydraulic engineering who are faced with the challenges of extending our understanding of hydraulic structures ranging from traditional to groundbreaking, as well as designing, constructing and managing safe, durable hydraulic structures that are economical ...

  7. Comparative study between two methods of estimating unsaturated hydraulic conductivity using neutron probe and terminates

    International Nuclear Information System (INIS)

    The aim of this study is to estimate the unsaturated hydraulic conductivity with a simplified in situ method comparing with other in situ methods. The simplified method depends on the combination work between tensiometers and neutron probe. Tensiometers were used to determine the soil matric potential (h) in tensiometric range (0 - 850 mbar) and the neutron probe was used to determine the next soil moisture content (q v). This method depends also on definition of Van Genuchten constants of fitting the soil moisture retention curve with simplified method. These constants are used in K (q) model of Van Genuchten to obtain K (q). Comparative study was done between the output of this method and other in situ methods. Good agreement had been found between the two methods

  8. Hydraulic model study of the cooling lake for the La Salle County Nuclear Power Plant

    International Nuclear Information System (INIS)

    A hydraulic model study of the cooling lake of the La Salle County Nuclear Power Station of Commonwealth Edison was performed. Two sizes of lake were investigated. In both cases various configurations of the internal, baffle-dike layout were studied to determine the configuration giving the best cooling performance. The experiments were performed by injecting a solution of Rhodamine WT fluorescent dye at the plant discharge and measuring the dye concentration at the plant intake at suitable time intervals. On the basis of a mathematical model developed, the temperature difference between the intake and equilibrium temperatures was determined as a function of the surface heat exchange coefficient. Prediction of excess temperature is made for full discharge through the plant, and for the discharge corresponding to only one unit of the power plant in operation. Several configurations using curved turning vane dikes were also tested

  9. HYDRAULIC SERVO

    Science.gov (United States)

    Wiegand, D.E.

    1962-05-01

    A hydraulic servo is designed in which a small pressure difference produced at two orifices by an electrically operated flapper arm in a constantly flowing hydraulic loop is hydraulically amplified by two constant flow pumps, two additional orifices, and three unconnected ball pistons. Two of the pistons are of one size and operate against the additional orifices, and the third piston is of a different size and operates between and against the first two pistons. (AEC)

  10. Advanced Cogeneration Technology Economic Optimization Study (ACTEOS)

    Science.gov (United States)

    Nanda, P.; Ansu, Y.; Manuel, E. H., Jr.; Price, W. G., Jr.

    1980-01-01

    The advanced cogeneration technology economic optimization study (ACTEOS) was undertaken to extend the results of the cogeneration technology alternatives study (CTAS). Cost comparisons were made between designs involving advanced cogeneration technologies and designs involving either conventional cogeneration technologies or not involving cogeneration. For the specific equipment cost and fuel price assumptions made, it was found that: (1) coal based cogeneration systems offered appreciable cost savings over the no cogeneration case, while systems using coal derived liquids offered no costs savings; and (2) the advanced cogeneration systems provided somewhat larger cost savings than the conventional systems. Among the issues considered in the study included: (1) temporal variations in steam and electric demands; (2) requirements for reliability/standby capacity; (3) availability of discrete equipment sizes; (4) regional variations in fuel and electricity prices; (5) off design system performance; and (6) separate demand and energy charges for purchased electricity.

  11. Prediction of hydraulic conductivity and conductive fracture frequency by multivariate analysis of data from the Klipperaas study site

    International Nuclear Information System (INIS)

    The present study is a pilot study on the possibility to predict the hydraulic conductivity and conductive fracture frequency in boreholes in crystalline rock using multivariate data analysis. The data set used was very extensive and included data from core mapping, fracture fillings, geophysical logs, tubewave measurements and hydraulic tests from five deep boreholes at the Klipperaas study site. In the study, multivariate data analysis proved to be a powerful technique to systematically analyze an extensive data material and to study different correlation structures within the data set. With the models derived, about 80-90% of the variation of hydraulic conductivity of an input data set (consisting of 233 conductivity values in 1 m-sections) could be explained by utilizing 35-45% of the total information contained in the data set. The hydraulic conductivity of about 4500 one meter sections was predicted. The predicted transmissivity was generally in good agreement with measured transmissivity values in 20 m-sections. The predicted values in 1 m-sections provided a more detailed picture of the hydraulic conductivity distribution along the boreholes. The predicted conductivities were found to be very unevenly distributed. The highest values generally occur in borehole intervals with altered and deformed rock with increased fracture density. The predicted conductive fracture frequency (CFF) was also unevenly distributed. Fissure fillings, in particular iron minerals, are regarded as useful information in predicting the CFF. The predicted average CFF of the rock mass varied between 0.17 0.25 (conductive) fractures per meter. This corresponds to an average fracture spacing of about 4-6 m. The frequency of subhorizontal fractures in granite generally correlates best to the hydraulic conductivity. The study also showed that both the geological and hydrogeological properties of different rock types may vary considerably within a site. (25 figs., 30 tabs., 35 refs.)

  12. The Effect of Loading Rate on Hydraulic Fracturing in Synthetic Granite - a Discrete Element Study

    Science.gov (United States)

    Tomac, I.; Gutierrez, M.

    2015-12-01

    Hydraulic fracture initiation and propagation from a borehole in hard synthetic rock is modeled using the two dimensional Discrete Element Method (DEM). DEM uses previously established procedure for modeling the strength and deformation parameters of quasi-brittle rocks with the Bonded Particle Model (Itasca, 2004). A series of simulations of laboratory tests on granite in DEM serve as a reference for synthetic rock behavior. Fracturing is enabled by breaking parallel bonds between DEM particles as a result of the local stress state. Subsequent bond breakage induces fracture propagation during a time-stepping procedure. Hydraulic fracturing occurs when pressurized fluid induces hoop stresses around the wellbore which cause rock fracturing and serves for geo-reservoir permeability enhancement in oil, gas and geothermal industries. In DEM, a network of fluid pipes and reservoirs is used for mathematical calculation of fluid flow through narrow channels between DEM particles, where the hydro-mechanical coupling is fully enabled. The fluid flow calculation is superimposed with DEM stress-strain calculation at each time step. As a result, the fluid pressures during borehole pressurization in hydraulic fracturing, as well as, during the fracture propagation from the borehole, can be simulated. The objective of this study is to investigate numerically a hypothesis that fluid pressurization rate, or the fluid flow rate, influences upon character, shape and velocity of fracture propagation in rock. The second objective is to better understand and define constraints which are important for successful fracture propagation in quasi-brittle rock from the perspective of flow rate, fluid density, viscosity and compressibility relative to the rock physical properties. Results from this study indicate that not only too high fluid flow rates cause fracture arrest and multiple fracture branching from the borehole, but also that the relative compressibility of fracturing fluid and

  13. Physico-chemical characterization of mortars as a tool in studying specific hydraulic components: application to the study of ancient Naxos aqueduct

    Science.gov (United States)

    Maravelaki-Kalaitzaki, P.; Galanos, A.; Doganis, I.; Kallithrakas-Kontos, N.

    2011-07-01

    Mortars and plasters from the ancient aqueduct on the island of Naxos, Greece, were studied with regard to mineralogical and chemical composition, grain size distribution, raw materials and hydraulic properties, in order to assess their characteristics and design compatible repair mortars. The authentic materials contained lime, crushed-brick, siliceous and calcitic aggregates, in different proportions according to mortar type. Crushed-bricks fired at low temperatures and lightweight volcanic aggregates contained amorphous phases, which upon reaction with lime yielded hydraulic components capable of protecting the construction from the continuous presence of water. Hydraulic calcium silicate/aluminate hydrates, the proportions and the perfect packing of the raw materials, along with the diligent application justify the longevity and durability of the studied samples. The hydraulic properties of samples were pointed out through (a) the well-established CO2/H2O ratio derived from the thermogravimetric analysis and (b) by introducing two powerful indices issued from the chemical analysis, namely CaOhydr and soluble SiO2 hydr. These indices improved the clustering of hydraulic mortars and provided better correlation between mortars, plasters and their binders. By comparing grain size distribution and hydraulicity indices it was possible to distinguish among the construction phases. Based on this study, repair mortars were formulated by hydraulic lime, siliceous sand, calcareous and crushed-brick aggregates, with the optimal water content, ensuring optimum workability and compatible appearance with the authentic ones.

  14. Study on the performance of the hydraulic and mass-transfer with miniature centrifugal contactor

    International Nuclear Information System (INIS)

    The hydraulic performance and the mass-transfer properties of HNO3, Fe3+, Nd3+ are studied in H2O-30% TRPO-kerosene system at different conditions with single-stage φ = 10 mm miniature centrifugal contactor. The rotor's speed varies from 4000 r/min to 4500 r/min. The total throughput is less than 600 mL/h. the phase ratio(o/a) changes from 1/10 to 10/1. Under the above experimental conditions, the single contactor operates very well and gives good performance. The stage efficiencies of HNO3 and Nd3+ are about 90%. The Fe3+ extraction is very slow kinetically and the stage efficiency of Fe3+ is low

  15. Study of radionuclides migration in hydraulic binders. Influence of binder alteration on transfer mechanisms and kinetic

    International Nuclear Information System (INIS)

    In the framework of low and medium activity wastes surface storage, hydraulic binders materials are usually used as containment barrier. The safety analysis of this storage mode involves the knowledge of their behaviour and of their retention capacity towards radionuclides, at short and long-term. The knowledge of diffusional processes inside their liquid phase and those of the interactions existing between the diffusing element and the cement matrix, as well as their kinetics, are essential elements for the study of their durability on 300 years. An experimental methodology has been defined, allowing the characterization of the transfer of an element j in a porous material by the determination of the diffusion coefficient of j in the pores of the material x and the determination of the local equilibrium constant characterizing the interaction of j with the material x. This can be made from the analytical expressions coming from the Fick laws. These parameters have been studied from diffusion and leaching experiments of radionuclides in pure cement pastes. A modelling of the leaching processes is proposed here. The decomposition of the hydraulic binders, by their leaching in a demineralized solution at 'aggressive' pH, leads essentially to their decalcification - whose kinetics answers to a pure diffusion law in √t - and an increase of their porosity. In these attack conditions, it seems that it exists a decalcification limit condition, from which a lattice of interconnected microcracks is developed in all the material. In consequence, the retention capacity of these degraded materials towards radionuclides decreases. The cesium transfer appears more sensitive to the degradation of the material than of those of the tritium. (O.M.)

  16. Study of the performance of four repairing material systems for hydraulic structures of concrete dams

    Directory of Open Access Journals (Sweden)

    Kormann A. C. M.

    2003-01-01

    Full Text Available Four types of repairing materials are studied as function of either a conventional concrete or a reference-concrete (RefC, these are: polymer-modified cement mortar (PMor, steel fiber concrete (SFco, epoxy mortar (EMor and silica fume mortar (SFmo, to be applied in hydraulic structures surfaces subjected to a high velocity water flow. Besides the mechanical requests and wearing resistance of hydraulic concrete dam structures, especially the spillway surfaces, the high solar radiation, the environmental temperature and wet and dry cycles, contribute significantly to the reduction of their lifespan. RefC and the SFco were developed based on a usual concrete mixture used in slabs of spillways. The average RefC mixture used was 1: 1.61: 2.99: 0.376, with Pozzolan-modified Portland cement consumption of 425 kg/m³. EMor and PMor mixtures followed the information given by the manufacturers and lab experience. Tests on concrete samples were carried out in laboratory simulating normally found environmental situations in order to control the mechanical resistance and the aging imposed conditions, such as solar radiation and humidity. Also, physicochemical characterizing tests were made for all used materials. From the analyzed results, two of them presented a higher performance: the EMor and SFmo. SFco presented good adherence to the RefC and good mechanical performance. However, it also presented apparent metal corrosion in humidity tests, being indicated for use, with caution, as an intermediate layer in underwater repairs. In a general classification, considering all tests, including their field applications, the better performance material systems were EMor- SFmo> SFco> PMor.

  17. Proceedings of the ANS/ASME/NRC international topical meeting on nuclear reactor thermal-hydraulics: LMFBR and HTGR advanced reactor concepts and analysis methods

    International Nuclear Information System (INIS)

    Separate abstracts are included for each of the papers presented concerning the thermal-hydraulics of LMFBR type reactors; mathematical methods in nuclear reactor thermal-hydraulics; heat transfer in gas-cooled reactors; and thermal-hydraulics of pebble-bed reactors. Two papers have been previously abstracted and input to the data base

  18. Core thermal-hydraulics behaviour within the framework of the feasibility studies of the RJH research reactor

    International Nuclear Information System (INIS)

    The purpose of this work is to give a preliminary evaluation of the thermal-hydraulic behaviour of the reactor Jules Horowitz (RJH project). These performances are evaluated by using computer codes. First a calculation procedure was drawn then the output data have been elaborated. The calculations are performed by using the operating code SIRENE which provides us with the boundary limits of the core. The 3-dimension thermal-hydraulic code FLICA-4 has allowed us to get an accurate behaviour of the core in various operating modes (nominal, accidental, natural convection). This work is only an introduction and further studies have to be led. (A.C.)

  19. An analytical study on excitation of nuclear-coupled thermal-hydraulic instability due to seismically induced resonance in BWR

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, Masashi [Japan Atomic Energy Research Institute, Ibaraki-ken (Japan)

    1997-07-01

    This paper describes the results of a scoping study on seismically induced resonance of nuclear-coupled thermal-hydraulic instability in BWRs, which was conducted by using TRAC-BF1 within a framework of a point kinetics model. As a result of the analysis, it is shown that a reactivity insertion could occur accompanied by in-surge of coolant into the core resulted from the excitation of the nuclear-coupled instability by the external acceleration. In order to analyze this phenomenon more in detail, it is necessary to couple a thermal-hydraulic code with a three-dimensional nuclear kinetics code.

  20. Advanced Subsonic Airplane Design and Economic Studies

    Science.gov (United States)

    Liebeck, Robert H.; Andrastek, Donald A.; Chau, Johnny; Girvin, Raquel; Lyon, Roger; Rawdon, Blaine K.; Scott, Paul W.; Wright, Robert A.

    1995-01-01

    A study was made to examine the effect of advanced technology engines on the performance of subsonic airplanes and provide a vision of the potential which these advanced engines offered. The year 2005 was selected as the entry-into-service (EIS) date for engine/airframe combination. A set of four airplane classes (passenger and design range combinations) that were envisioned to span the needs for the 2005 EIS period were defined. The airframes for all classes were designed and sized using 2005 EIS advanced technology. Two airplanes were designed and sized for each class: one using current technology (1995) engines to provide a baseline, and one using advanced technology (2005) engines. The resulting engine/airframe combinations were compared and evaluated on the basis on sensitivity to basic engine performance parameters (e.g. SFC and engine weight) as well as DOC+I. The advanced technology engines provided significant reductions in fuel burn, weight, and wing area. Average values were as follows: reduction in fuel burn = 18%, reduction in wing area = 7%, and reduction in TOGW = 9%. Average DOC+I reduction was 3.5% using the pricing model based on payload-range index and 5% using the pricing model based on airframe weight. Noise and emissions were not considered.

  1. EFFECT FOR A SINGLE ROUGHNESS E=5,63mm OF EXPERIMENTAL TO STUDY HYDRAULIC JUMP PROFILE IN A CHANNEL IN U A ROUGH BOTTOM

    Directory of Open Access Journals (Sweden)

    A. Ghomri

    2015-07-01

    Full Text Available This study aims to study the hydraulic jump controlled by threshold, moving in a channel profile 'U' bottomed rough for a single roughness E=5,63mm. Functional relations in dimensionless terms, linking the different characteristics of the projection, showing the effect of roughness of the bottom of the channel are obtained. The hydraulic jump is the primary means used by hydraulic structures to dissipate energy. This hydraulic jump is formed at the sharp transition from a supercritical flow a stream flow.

  2. EFFECT FOR A SINGLE ROUGHNESS E=5,63mm OF EXPERIMENTAL TO STUDY HYDRAULIC JUMP PROFILE IN A CHANNEL IN U A ROUGH BOTTOM

    Directory of Open Access Journals (Sweden)

    A. Ghomri

    2013-06-01

    Full Text Available This study aims to study the hydraulic jump controlled by threshold, moving in a channel profile 'U' bottomed rough for a single roughness E=5,63mm. Functional relations in dimensionless terms, linking the different characteristics of the projection, showing the effect of roughness of the bottom of the channel are obtained. The hydraulic jump is the primary means used by hydraulic structures to dissipate energy. This hydraulic jump is formed at the sharp transition from a supercritical flow a stream flow.

  3. Development and testing of improved polyimide actuator rod seals at higher temperatures for use in advanced aircraft hydraulic systems

    Science.gov (United States)

    Robinson, E. D.; Waterman, A. W.; Nelson, W. G.

    1972-01-01

    Polyimide second stage rod seals were evaluated to determine their suitability for application in advanced aircraft systems. The configurations of the seals are described. The conditions of the life cycle tests are provided. It was determined that external rod seal leakage was within prescribed limits and that the seals showed no signs of structural degradation.

  4. NATO Advanced Study Institute on Advances in Microlocal Analysis

    CERN Document Server

    1986-01-01

    The 1985 Castel vecchio-Pas coli NATO Advanced Study Institute is aimed to complete the trilogy with the two former institutes I organized : "Boundary Value Problem for Evolution Partial Differential Operators", Liege, 1976 and "Singularities in Boundary Value Problems", Maratea, 1980. It was indeed necessary to record the considerable progress realized in the field of the propagation of singularities of Schwartz Distri­ butions which led recently to the birth of a new branch of Mathema­ tical Analysis called Microlocal Analysis. Most of this theory was mainly built to be applied to distribution solutions of linear partial differential problems. A large part of this institute still went in this direction. But, on the other hand, it was also time to explore the new trend to use microlocal analysis In non linear differential problems. I hope that the Castelvecchio NATO ASI reached its purposes with the help of the more famous authorities in the field. The meeting was held in Tuscany (Italy) at Castelvecchio-P...

  5. Computational and experimental study of effects of sediment shape on erosion of hydraulic turbines

    International Nuclear Information System (INIS)

    Hard particles as Quartz and Feldspar are present in large amount in most of the rivers across the Himalayan basins. In run-off-river hydro power plants these particles find way to turbine and cause its components to erode. Loss of turbine material due to the erosion and subsequent change in flow pattern induce several operational and maintenance problems in the power plants. Reduction in overall efficiency, vibrations and reduced life of turbine components are the major effects of sediment erosion of hydraulic turbines. Sediment erosion of hydraulic turbines is a complex phenomenon and depends upon several factors. One of the most influencing parameter is the characteristics of sediment particles. Quantity of sediment particles, which are harder than the turbine material, is one of the bases to indicate erosion potential of a particular site. Research findings have indicated that shape and size of the hard particles together with velocity of impact play a major role to decide the mode and rate of erosion in turbine components. It is not a common practice in Himalayan basins to conduct a detail study of sediment characteristics as a part of feasibility study for hydropower projects. Lack of scientifically verified procedures and guidelines to conduct the sediment analysis to estimate its erosion potential is one of the reasons to overlook this important part of feasibility study. Present study has been conducted by implementing computational tools to characterize the sediment particles with respect to their shape and size. Experimental studies have also been done to analyze the effects of different combinations of shape and size of hard particles on turbine material. Efforts have also been given to develop standard procedures to conduct similar study to compare erosion potential between different hydropower sites. Digital image processing software and sieve analyzer have been utilized to extract shape and size of sediment particles from the erosion sensitive power

  6. Advances and challenges in innovation studies

    OpenAIRE

    Castellacci, F.; Grodal, S.; Mendonça, S; Wibe, M.

    2005-01-01

    The article discusses recent advances and future challenges in innovation studies. First, it separately considers four main strands of research, studying innovation at the organizational, systemic, sectoral and macroeconomic levels. Then, considering the field as a whole, the article points to the existence of important neglected topics and methodological challenges for future research. In fact, several fundamental issues are still unexplored, such as the co-evolution betwee...

  7. IN-SERVICE HYDRAULIC CONDUCTIVITY OF GCLS IN LANDFILL COVERS - LABORATORY AND FIELD STUDIES

    Science.gov (United States)

    Laboratory experiments using multi-species inorganic solutions (containing calcium and sodium) were conducted on specimens of a new geosynthetic clay liner (GCL) containing sodium bentonite to determine how cation exchange and desiccation affected the hydraulic conductivity. Calc...

  8. Basic hydraulics

    CERN Document Server

    Smith, P D

    2013-01-01

    BASIC Hydraulics aims to help students both to become proficient in the BASIC programming language by actually using the language in an important field of engineering and to use computing as a means of mastering the subject of hydraulics. The book begins with a summary of the technique of computing in BASIC together with comments and listing of the main commands and statements. Subsequent chapters introduce the fundamental concepts and appropriate governing equations. Topics covered include principles of fluid mechanics; flow in pipes, pipe networks and open channels; hydraulic machinery;

  9. Hydraulic testing plan for the Bear Creek Valley Treatability Study, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    The Bear Creek Valley (BCV) Treatability Study is intended to provide site-specific data defining potential treatability technologies applicable to contaminated groundwater and surface water. The ultimate goal of this effort is to install a treatment system that will remove uranium, technetium, nitrate, and several metals from groundwater before it reaches Bear Creek. This project directly supports the BCV Feasibility Study. Part of the Treatability Study, Phase II Hydraulic Performance Testing, will produce hydraulic and treatment performance data required to design a long-term treatment system. This effort consists of the installation and testing of two groundwater collection systems: a trench in the vicinity of GW-835 and an angled pumping well adjacent to NT-1. Pumping tests and evaluations of gradients under ambient conditions will provide data for full-scale design of treatment systems. In addition to hydraulic performance, in situ treatment chemistry data will be obtained from monitoring wells installed in the reactive media section of the trench. The in situ treatment work is not part of this test plan. This Hydraulic Testing Plan describes the location and installation of the trench and NT-1 wells, the locations and purpose of the monitoring wells, and the procedures for the pumping tests of the trench and NT-1 wells

  10. Use of hydraulic and aerial mock up to study atmospheric pollution

    International Nuclear Information System (INIS)

    Fundamental studies on turbulent atmospheric diffusion of finely divided particles, cannot remain on a purely theoretical basis. Further experimental studies must be considered. - In full scale, from accidental and induced releases. - On a reduced scale, in aerodynamic wind tunnels or hydraulic water tunnels. A first set of studies on reduced scale models has been worked out according to a contract between French 'Meteorologie Nationale' and French 'Commissariat a l'Energie Atomique' and with the Collaboration of Saint-Cyr 'Institut Aerotechnique'. Essentially two kinds of results have been obtained: - The mathematical model of SUTTON for the turbulent diffusion in the atmosphere, deduced from the SUTTON theory, generally used by us, has been correctly verified, qualitatively and quantitatively whenever experiments were consistent with the theory conditions. - The quantitative assays of photographic and cinematographic visualization have given precise details on the phenomena inaccessible to calculations, due to the influence of obstacles and release conditions. - Generally, it can be asserted, that the atmospheric pollution studies are worked out by mock up experimentations and that, in some cases these experiments never can be replaced by mathematically pure models. (authors)

  11. Experimental Identification and Study of Hydraulic Resonance Test Rig with Francis Turbine operating at Partial Load

    OpenAIRE

    Favrel, Arthur; Landry, Christian; Müller, Andres; Avellan, François

    2013-01-01

    Resonance in hydraulic systems is characterized by pressure fluctuations of high amplitude which can lead to undesirable and dangerous effects, such as noise, vibration and structural failure. For a Francis turbine operating at partial load, the cavitating vortex rope developing at the outlet of the runner induces pressure fluctuations which can excite the hydraulic system resonance, leading to undesirable large torque and power fluctuations. At resonant operating points, the prediction of am...

  12. Improved design of hydroelectric projects : hydraulic roughness of TBM-bored tunnels. An experimental study.

    OpenAIRE

    Katarzyna Filipek; Anna Kasprzyk

    2011-01-01

    The purpose of this thesis is to link head loss coefficients in rough pipes to the physical roughness of the surface through measurements of head loss in fully turbulent flow. It is generally regarded that hydraulic roughness is some function of the height, spacing, density and nature of the physical roughness under consideration. Attempts have been made to link hydraulic roughness to physical roughness of an irregular surface. Those have, however, been incomplete and conducted at flow states...

  13. Experimental study of step-displacement hydraulic fracturing on naturally fractured shale outcrops

    Science.gov (United States)

    Cheng, Wan; Jin, Yan; Chen, Mian

    2015-08-01

    Low porosity and permeability make it extremely difficult to develop shale oil and gas reservoirs. The stimulated reservoir volume is believed to have potential to obtain industry production by multi-stage or simultaneous fracturing in horizontal wells. The formation mechanism of network hydraulic fractures in fractured shale reservoirs remains poorly understood. In this article, a true tri-axial hydraulic fracturing system associated acoustic emission monitor was deployed to simulate hydraulic fracturing on shale outcrops. Results showed that the properties of natural fractures (such as aperture, orientation), compared to the viscosity and displacement of the fracturing fluid, affect the propagation direction of hydraulic fractures more predominantly. Each natural fracture in a natural fracture network can independently affect the hydraulic fracture. Low displacement (below the diffusion ability of a reservoir) fracturing tends to connect pre-existing fractures, while high displacement (surpass the diffusion ability of a reservoir) tends to create new fractures. After the breakdown pressure, an increase in injection rate results in more acoustic emission energy and induces new fractures. These results suggest that step-displacement fracturing technology is a possible mechanism to obtain effective fracture networks. Such an understanding would help to avoid unproductive, or sometimes destructive, costly segments of the hydraulic fracturing treatment design.

  14. Advanced Cell Development and Degradation Studies

    Energy Technology Data Exchange (ETDEWEB)

    J. E. O' Brien; C. M. Stoots; J. S. Herring; R. C. O' Brien; K. G. Condie; M. Sohal; G. K. Housley; J. J. Hartvigsen; D. Larsen; G. Tao; B. Yildiz; V. Sharma; P. Singh; N. Petigny; T. L. Cable

    2010-09-01

    The Idaho National Laboratory (INL) has been researching the application of solid-oxide electrolysis cells for large-scale hydrogen production from steam over a temperature range of 800 to 900ºC. From 2003 – 2009, this work was sponsored by the DOE Nuclear Hydrogen Initiative (NHI). Starting in 2010, the HTE research program has been sponsored by the Next Generation Nuclear Plant (NGNP) program. HTSE research priorities in FY10 are centered on understanding and reducing cell and stack performance degradation to an acceptable level to advance the technology readiness level of HTSE and to justify further large-scale demonstration activities. This report provides a summary of our FY10 experimental program, which has been focused on advanced cell and stack development and degradation studies. Advanced cell and stack development activities are under way at five technology partners: MSRI, Versa Power, Ceramatec, NASA Glenn, and St. Gobain. Performance evaluation of the advanced technology cells and stacks has been performed by the technology partners, by MIT and the University of Connecticut and at the INL HTE Laboratory. Summaries of these development activities and test results are presented.

  15. Study on thermal-hydraulic phenomena in porous media. Semiannual report Apr. 1998 to Mar. 1999

    International Nuclear Information System (INIS)

    This study deals with thermal-hydraulic phenomena in a porous media. When the foreign substances flow into the fuel subassembly with wire spacer, they would choke up the subchannel and form a porous blockage. The objective of this study is to clarify the thermalhydraulic phenomena in porous media and to develop the analytical method to predict the thermal-hydraulic field, deciding the maximum temperature on the fuel pin surface. This study is performed in cooperation with University of Tsukuba and Japan Nuclear Cycle Development Institute (JNC) from November 1997 to March 2000. This report describes the results for the second period from April 1998 to March 1999. In the last year, we confirmed that the visualization method used NaI solution as working fluid was applicable to flow visualization in the porous media. In this year period, we conducted the experiment to measure the velocity field inside and outside the blockage used Particle Image Velocimetry (PIV) analysis and Laser Doppler Velocimetry (LDV). The test section was simplified and 20 times enlarged the two subchannel of the fuel subassembly in the reactor, included the porous blockage consisted of the Pyrex grass spheres. NaI solution was used as the working fluid. When the concentration of NaI is 56.9wt% in the solution, the refraction-rate is correspond to that of the Pyrex grass. Before the experiment, we measured the density, viscosity, and thermal conductivity of 56.9wt% NaI solution. The velocity profile inside and outside the blockage was measured in detail. The knowledge was acquired of the relation of the flow in between the blockage and the unplugged channel. Moreover, we tried to measure the fluid temperature inside the blockage in the NaI solution, used Laser Induced Fluorescence (LIF) method. At the fist, we checked the relation between the brightness of the fluorescence and solution temperature. And then, we revealed that the LIF method could be used even in the NaI solution. (author)

  16. Hydraulic Structures

    Data.gov (United States)

    Department of Homeland Security — This table is required whenever hydraulic structures are shown in the flood profile. It is also required if levees are shown on the FIRM, channels containing the...

  17. Selection of the 700 MWe PHWR pressuriser level control program through thermal hydraulic transient studies

    International Nuclear Information System (INIS)

    design basis, though this is not an operational event. This paper describes the computer simulation model that has been developed for the upcoming 700 MWe PHWR using internationally renowned, best estimate RELAP5/MOD3.2 code for the thermal hydraulic behavior. The output from these simulation studies is being utilized for performance verification of the PHT system pressure controller and the Pressuriser level control program. Earlier such studies have been performed for the 540 MWe PHWR power plants. The 700 MWe PHWR SGs differs from the earlier SGs in many of the design details. The implication of these details on the thermal hydraulic behavior and the corresponding impact on the design will be discussed. (author)

  18. Pressure Safety: Advanced Self-Study 30120

    Energy Technology Data Exchange (ETDEWEB)

    Glass, George [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-29

    Pressure Safety Advance Self-Study (Course 30120) consists of an introduction, five modules, and a quiz. To receive credit in UTrain for completing this course, you must score 80% or better on the 15-question quiz (check UTrain). Directions for initiating the quiz are appended to the end of this training manual. This course contains several links to LANL websites. UTrain might not support active links, so please copy links into the address line in your browser.

  19. A study of factors influencing advanced puberty

    OpenAIRE

    Yong Jun Park; Chang Min Moon; Hwang Jae Yoo

    2010-01-01

    Purpose : The purpose of this study was to evaluate the timing of puberty and the factors inducing advanced puberty in elemental school students of low grades. Methods : The 1st, 2nd, and 3rd grade elemental students from the Goyang province were randomly selected, and their sexual maturation rate was assessed by physical examination. After obtaining an informed consent, a questionnaire was administered to the parents; eating habits, lifestyle, use of growth-inducing medication, and prese...

  20. Study of thermal hydraulic behaviors during steam generator multiple tube rupture events in PWR

    International Nuclear Information System (INIS)

    Since the occurrence probability of multiple steam generator tube rupture (MSGTR) in PWR is low, analytical or experimental investigation for termination of such accidents is not performed explicitly. Therefore, thermal-hydraulic analysis of the plant behavior under the MSGTR (10 and 50 tubes) in all loops or in a single loop with station black out (SBO) were made in this study with use of the code RETRAN3D, and investigations for accident management (AM) of such accidents were made in order to contribute to continuous risk reduction efforts in the future. This study indicated that the water supply function to the SG is quite important for coping with accidents involving MSGTR accompanied by SBO to prevent core damage. Further, if the auxiliary feed water system loses its function, the time to reach the core exposure is predicted to be reduced by 1 hour or more in a MSGTR case as compared to a single-tube SGTR case. Therefore, in order to prevent the core damage during MSGTR, it is desirable to have alternative water injection equipment operable to quickly replace auxiliary feed water system if it fails and to increase the reliability of the auxiliary feed water system. (author)

  1. Center for Advanced Energy Studies Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Kostelnik

    2005-09-01

    The world is facing critical energy-related challenges regarding world and national energy demands, advanced science and energy technology delivery, nuclear engineering educational shortfalls, and adequately trained technical staff. Resolution of these issues is important for the United States to ensure a secure and affordable energy supply, which is essential for maintaining U.S. national security, continued economic prosperity, and future sustainable development. One way that the U.S. Department of Energy (DOE) is addressing these challenges is by tasking the Battelle Energy Alliance, LLC (BEA) with developing the Center for Advanced Energy Studies (CAES) at the Idaho National Laboratory (INL). By 2015, CAES will be a self-sustaining, world-class, academic and research institution where the INL; DOE; Idaho, regional, and other national universities; and the international community will cooperate to conduct critical energy-related research, classroom instruction, technical training, policy conceptualization, public dialogue, and other events.

  2. Thermal-hydraulic studies on the safety of VVER-440 type nuclear power plants

    International Nuclear Information System (INIS)

    The thesis includes several thermal-hydraulic analyses related to the Loviisa VVER-440 nuclear power plant units. The work consists of experimental studies, analysis of the experiments, analysis of some plant transients and development of a calculational model for calculation of boric concentrations in the reactor. In the first part of thesis, in the case of simulation of boric acid solution behaviour during long-term cooling period of LOCAs, experiments were performed in scaled-down test facilities. The experimental data together with the results of RELAP5/MOD3 simulations were used to develop a model for calculations of boric acid concentrations in the reactor during LOCAs. In the second part, in the case of simulation of horizontal generators, experiments were performed with PACTEL integral test loop to simulate loss of feedwater transients. The PACTEL experiments as well as earlier REWETT-III natural circulation tests, were analyzed with RELAP5/MOD3 Version 5m5 code. The third part of the work consists of simulations of Loviisa VVER reactor pump trip transients with RELAP5/MOD1-Eur, RELAP5/MOD3 and CATHARE codes. (56 refs., 9 figs.)

  3. Experimental and analytical study on thermal hydraulics in reduced-moderation water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Akimoto, Hajime; Araya, Fumimasa; Ohnuki, Akira; Yoshida, Hiroyuki; Kureta, Masatoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2000-06-01

    Study and development of reduced-moderation spectrum water reactor proceeds as a option of the future type reactor in Japan Atomic Energy Research Institute (JAERI). The reduced-moderation spectrum in which a neutron has higher energy than the conventional water reactors is achieved by decreasing moderator-to-fuel ratio in the lattice core of the reactor. Conversion ratio in the reduced-moderation water reactor can be more than 1.0. High burnup and long term cycle operation of the reactor are expected. A type of heavy water cooled PWR and three types of BWR are discussed as follows; For the PWR, (1) critical heat flux experiments in hexagonal tight lattice core, (2) evaluation of cooling limit at a nominal power operation, and (3) analysis of rewetting cooling behavior at loss of coolant accident following with large scale pipe rupture. For the BWR, analyses of cooling limit at a nominal power operation of, (1) no blanket BWR, (2) long term cycle operation BWR, and (3) high conversion ratio BWR. The experiments and the analyses proved that the basic thermal hydraulic characteristics of these reduced-moderation water reactors satisfy the essential points of the safety requirements. (Suetake, M.)

  4. Study of thermal hydraulic behavior of supercritical water flowing through fuel rod bundles

    International Nuclear Information System (INIS)

    Investigations on thermal-hydraulic behavior in Supercritical Water Reactor (SCWR) fuel assembly have obtained a significant attention in the international SCWR community because of its potential to obtain high thermal efficiency and compact design. Present work deals with CFD analysis to study the flow and heat transfer behavior of supercritical water in 4 metre long 7-pin fuel bundle using commercial CFD package ANSYS CFX for single phase steady state conditions. Considering the symmetric conditions, 1/12th part of the fuel rod bundle is taken as a domain of analysis. RNG K-epsilon model with scalable wall functions is used for modeling the turbulence behavior. Constant heat flux boundary condition is applied at the fuel rod surface. IAPWS equations of state are used to compute thermo-physical properties of supercritical water. Sharp variations in its thermo-physical properties (specific heat, density) are observed near the pseudo-critical temperature causing sharp change in heat transfer coefficient. The pseudo-critical point initially appears in the gaps among heated fuel rods, and then spreads radially outward reaching the adiabatic wall as the flow goes downstream. The enthalpy gain in the centre of the channel is much higher than that in the wall region. Non-uniformity in the circumferential distribution of surface temperature and heat transfer coefficient is observed which is in agreement with published literature. Heat transfer coefficient is high on the rod surface near the tight region and decreases as the distance between rod surfaces increases. (author)

  5. A study on the optimal hydraulic loading rate and plant ratios in recirculation aquaponic system.

    Science.gov (United States)

    Endut, Azizah; Jusoh, A; Ali, N; Wan Nik, W B; Hassan, A

    2010-03-01

    The growths of the African catfish (Clarias gariepinus) and water spinach (Ipomoea aquatica) were evaluated in recirculation aquaponic system (RAS). Fish production performance, plant growth and nutrient removal were measured and their dependence on hydraulic loading rate (HLR) was assessed. Fish production did not differ significantly between hydraulic loading rates. In contrast to the fish production, the water spinach yield was significantly higher in the lower hydraulic loading rate. Fish production, plant growth and percentage nutrient removal were highest at hydraulic loading rate of 1.28 m/day. The ratio of fish to plant production has been calculated to balance nutrient generation from fish with nutrient removal by plants and the optimum ratio was 15-42 gram of fish feed/m(2) of plant growing area. Each unit in RAS was evaluated in terms of oxygen demand. Using specified feeding regime, mass balance equations were applied to quantify the waste discharges from rearing tanks and treatment units. The waste discharged was found to be strongly dependent on hydraulic loading rate. PMID:19819130

  6. TRAC-PF1/MOD1: an advanced best-estimate computer program for pressurized water reactor thermal-hydraulic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Liles, D.R.; Mahaffy, J.H.

    1986-07-01

    The Los Alamos National Laboratory is developing the Transient Reactor Analysis Code (TRAC) to provide advanced best-estimate predictions of postulated accidents in light-water reactors. The TRAC-PF1/MOD1 program provides this capability for pressurized water reactors and for many thermal-hydraulic test facilities. The code features either a one- or a three-dimensional treatment of the pressure vessel and its associated internals, a two-fluid nonequilibrium hydrodynamics model with a noncondensable gas field and solute tracking, flow-regime-dependent constitutive equation treatment, optional reflood tracking capability for bottom-flood and falling-film quench fronts, and consistent treatment of entire accident sequences including the generation of consistent initial conditions. The stability-enhancing two-step (SETS) numerical algorithm is used in the one-dimensional hydrodynamics and permits this portion of the fluid dynamics to violate the material Courant condition. This technique permits large time steps and, hence, reduced running time for slow transients.

  7. TRAC-PF1/MOD1: an advanced best-estimate computer program for pressurized water reactor thermal-hydraulic analysis

    International Nuclear Information System (INIS)

    The Los Alamos National Laboratory is developing the Transient Reactor Analysis Code (TRAC) to provide advanced best-estimate predictions of postulated accidents in light-water reactors. The TRAC-PF1/MOD1 program provides this capability for pressurized water reactors and for many thermal-hydraulic test facilities. The code features either a one- or a three-dimensional treatment of the pressure vessel and its associated internals, a two-fluid nonequilibrium hydrodynamics model with a noncondensable gas field and solute tracking, flow-regime-dependent constitutive equation treatment, optional reflood tracking capability for bottom-flood and falling-film quench fronts, and consistent treatment of entire accident sequences including the generation of consistent initial conditions. The stability-enhancing two-step (SETS) numerical algorithm is used in the one-dimensional hydrodynamics and permits this portion of the fluid dynamics to violate the material Courant condition. This technique permits large time steps and, hence, reduced running time for slow transients

  8. Electro Hydraulic Hitch Control

    DEFF Research Database (Denmark)

    Hansen, M. R.; Andersen, T. O.; Nielsen, B.;

    2003-01-01

    This paper present and discusses R&D results on electro hydraulic hitch control for off-road vehicle, in particular active damping of oscillation occuring on tractors. The research deals with analysis and control of the oscillations occuring on tractors which are design without any susspection...... for a parameter research study with emphasis on the requirements to the hitch control by use of hydraulic pressure compensated proportional control valve....

  9. Numerical study of the thermo-hydraulic behavior for the Candu type fuel channel

    International Nuclear Information System (INIS)

    Candu type reactors use fuel channel in a horizontal lattice. The fuel bundles are positioned in two Zircaloy tubes: the pressure tube surrounded by calandria tube. Inside the pressure tube the coolant heavy water flows. The coolant reaches high temperatures and pressures. Due to irregular neutron spatial distribution, the fuel channel stress differs from one channel to other. In one improbable event of severe accident, the fuel channel behaves differently according to its normal function history. Over the years, there have been many research projects trying to analyze thermal hydraulic performance of the design and to add some operational improvements in order to achieve an efficient thermal hydraulic distribution. This paper discusses the thermo hydraulic behavior (influence of the temperature and velocity distribution) of the most solicited channel, simulated with Fluent 6.X. Code. Moreover it will be commented the results obtained using different models and mesh applied. (authors)

  10. The study on measures to improve the reliability of the hydraulic systems of shearers

    Institute of Scientific and Technical Information of China (English)

    袁辉; 徐龙江; 田大宝; 赵燕玲

    2001-01-01

    The authors indicate that the failure of hydraulic systems of shearers can drop greatly, its' reliability and service life can be increased by the use of a field oil contamination analyser and filter device to control the oil contamination of the hydraulic systems of shearers. Experimental provement of silting-theory contamination analyser are carried out. The filter effect of portable hydraulic driving oil-filter model YLJ-21 is examinationed in laboratory and field experiment. From January to August 1992, on-site experimental research using a silting-theory contamination analyser and oil-filter model YLJ-21 to control the oil contamination was carried out in the Datong Coat Mining Bureau.

  11. A study of factors influencing advanced puberty

    Directory of Open Access Journals (Sweden)

    Yong Jun Park

    2010-02-01

    Full Text Available Purpose : The purpose of this study was to evaluate the timing of puberty and the factors inducing advanced puberty in elemental school students of low grades. Methods : The 1st, 2nd, and 3rd grade elemental students from the Goyang province were randomly selected, and their sexual maturation rate was assessed by physical examination. After obtaining an informed consent, a questionnaire was administered to the parents; eating habits, lifestyle, use of growth-inducing medication, and present illness of the students were evaluated to determine the factors that induced advanced puberty. The data were statistically analyzed. Results : We selected 170 children and the girls:boys sex ratio was 1.2:1. Two 9-year-old boys were in genital stage 2. Two (14.3% 6-year-old girls, 6 (19.4% 7-year-old girls, 15 (39.6% 8-year-old girls, and 4 (57.1% 9-year-old girls were in breast stage 2. The average pubertal timing predicted for girls was 9.11¡?#?.86; years. The main factors influencing pubertal timing were obesity scale, frequency of eating fast food, and the use of growth-inducing medication. A high rating on the obesity scale and high frequency of eating fast food indicated advanced stage of puberty. Growth-inducing medication induced puberty through obesity. Conclusion : We proposed that predictive average pubertal timing in girls was 9.11¡?#?.86; years, which was consistent with the previously reported findings from abroad. The significant influencing factors in advanced puberty were obesity scale and frequency of fast food.

  12. Feasibility study on the development of advanced LWR fuel technology

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Youn Ho; Sohn, D. S.; Jeong, Y. H.; Song, K. W.; Song, K. N.; Chun, T. H.; Bang, J. G.; Bae, K. K.; Kim, D. H. and others

    1997-07-01

    Worldwide R and D trends related to core technology of LWR fuels and status of patents have been surveyed for the feasibility study. In addition, various fuel cycle schemes have been studied to establish the target performance parameters. For the development of cladding material, establishment of long-term research plan for alloy development and optimization of melting process and manufacturing technology were conducted. A work which could characterize the effect of sintering additives on the microstructure of UO{sub 2} pellet has been experimentally undertaken, and major sintering variables and their ranges have been found in the sintering process of UO{sub 2}-Gd{sub 2}O{sub 3} burnable absorber pellet. The analysis of state of the art technology related to flow mixing device for spacer grid and debris filtering device for bottom nozzle and the investigation of the physical phenomena related to CHF enhancement and the establishment of the data base for thermal-hydraulic performance tests has been done in this study. In addition, survey on the documents of the up-to-date PWR fuel assemblies developed by foreign vendors have been carried out to understand their R and D trends and establish the direction of R and D for these structural components. And, to set the performance target of the new fuel, to be developed, fuel burnup and economy under the extended fuel cycle length scheme were estimated. A preliminary study on the failure mechanism of CANDU fuel, key technology and advanced coating has been performed. (author). 190 refs., 31 tabs., 129 figs.

  13. Study for establishment of the methodology for hydrogeological modeling using hydraulic discrete fracture networks. Study on hydrogeology in crystalline fractured rock

    International Nuclear Information System (INIS)

    Japan Atomic Energy Agency is performing the Mizunami Underground Research Laboratory (MIU) Project, which is a broad scientific study of the deep geological environment as a basis of research and development for geological disposal of nuclear wastes, in order to establish comprehensive techniques for the investigation, analysis and assessment of the deep geological environment in fractured crystalline rock. The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III) years. One of the project goals of the MIU Project from Phase I through to Phase III are: to establish techniques for investigation, analysis and assessment of the deep geological environment. Aim of the study is to develop the methodology for hydrogeological modeling considering the hydraulic heterogeneity due to the water conducting features in fractured rocks for achievement of the project goal. In this study, water conducting features in Toki granite were defined by the interpretation and integration of geological and hydrogeological data obtained from the borehole investigation in the Phase I of the MIU Project and Regional Hydrogeological Study. Then, the hydrogeological model of Block scale was constructed using hydraulic discrete fracture networks, and equivalent hydraulic conductivities in Block scale were calculated. And, adequacy of equivalent hydraulic conductivities in Block scale was confirmed using result of hydraulic packer tests. (author)

  14. Recent advance in study on FAC

    International Nuclear Information System (INIS)

    Flow accelerated corrosion (FAC) is an important issue for aging fossil and nuclear power plants. FAC causes thinning of pipe walls which occasionally leads to a piping rupture accident. 'Research Committee on Improvement and Practical Use of Pipe-Wall-Thinning Management' of JSME revised technical knowledge regarding pipe wall thinning phenomena attached to JSME 'Code for Power Generation Facilities - Rule on Pipe Wall Thinning Management-JSME-S CA1 2005.' This paper summarizes the technical knowledge of recent advances in study on FAC. (author)

  15. Advanced SFR concept design studies at KAERI

    International Nuclear Information System (INIS)

    Full text: Advanced SFR design concepts have been proposed and evaluated against the design requirements to satisfy the Gen IV technology goals. Two types of conceptual core designs, Breakeven and TRU burner cores were developed. Breakeven core is 1,200 MWe and does not have blankets to enhance the proliferation resistance. According to the current study, TRU burning rate increases linearly with the rated core powers from 600 MWe to 1,200 MWe. Considering 1) the realistic size of an SFR demonstration reactor for the long-term R and D plan with the goal of a demonstration SFR construction by 2028, and 2) the availability of a KALIMER-600 reactor system design that was developed in the last R and D phase, a TRU burner of 600 MWe was selected. The heat transport system of Advanced SFR was designed to be a pool type to enhance system safety through slow system transients, where primary sodium is contained in a reactor vessel. The heat transport system is composed of Primary Heat Transport System (PHTS), Intermediate Heat Transport System (IHTS), Steam Generating System (SGS) and Residual Heat Removal System (RHRS). The heat transport system was established through trade studies in order to enhance the safety and to improve the economics and performance of the KALIMER-600 design. Trade studies were performed for the number of IHTS loops, the number of PHTS pumps, Steam Generator (SG) design concepts, energy conversion system concepts, cover gas operation methods, and an improved concept of safety-graded passive decay heat removal system. From the study, the heat transport system of Advanced SFR has design features such as two IHTS loops, a Rankine cycle energy conversion system, two double-wall straight tube type SGs, and a passive decay heat removal system. In order to secure the economic competitiveness of an SFR, several concepts were implemented in the mechanical structural design without losing the reactor safety level. The material of reactor vessel and internal

  16. Technological advances for studying human behavior

    Science.gov (United States)

    Roske-Hofstrand, Renate J.

    1990-01-01

    Technological advances for studying human behavior are noted in viewgraph form. It is asserted that performance-aiding systems are proliferating without a fundamental understanding of how they would interact with the humans who must control them. Two views of automation research, the hardware view and the human-centered view, are listed. Other viewgraphs give information on vital elements for human-centered research, a continuum of the research process, available technologies, new technologies for persistent problems, a sample research infrastructure, the need for metrics, and examples of data-link technology.

  17. A comparative study of various advanced fusions

    International Nuclear Information System (INIS)

    For the purpose of comparing the merits and demerits of various advanced fuel cycles, parametric studies of operation conditions are examined. The effects of nuclear elastic collisions and synchrotron radiation are taken into account. It is found that the high-#betta# Catalyzed DD fuel cycle with the transmutation of fusion-produced tritium into helium-3 is most feasible from the point of view of neutron production and tritium handling. The D-D fuel cycles seem to be less attractive compared to the Catalyzed DD. The p-11B and p-6Li fusion plasmas hardly attain the plasma Q value relevant to reactors. (author)

  18. Mineralogical study and leaching behavior of a stabilized harbor sediment with hydraulic binder.

    Science.gov (United States)

    Chatain, Vincent; Benzaazoua, Mostafa; Loustau Cazalet, Marie; Bouzahzah, Hassan; Delolme, Cécile; Gautier, Mathieu; Blanc, Denise; de Brauer, Christine

    2013-01-01

    The environmental assessment of potential effects of contaminated harbor sediments stabilized with hydraulic binders and the determination of remediation endpoints require the determination of pollutants leaching potentials. Moreover, little information about the speciation and mobility of inorganic contaminants in these specific solid matrices is available in the literature. The objective of this paper is to investigate the relationship between mineralogy and leachability of contaminants (copper, lead, and zinc) present in a French harbor sediment stabilized with quicklime and Portland cement. Batch equilibrium leaching tests at various pH, chemical analysis of leachates, and mineralogical studies (X-ray diffraction, scanning electron microscopy-energy dispersive spectroscopy, and diffuse reflectance infrared Fourier transform) have been combined in the present investigation. The acid neutralization capacity of the stabilized matrix studied is first controlled by the dissolution of portlandite (pH ~12), followed by the dissolution of C-S-H (pH ~11) and the dissolution of ettringite (pH ~10). Finally, a very high buffering capacity of this stabilized sediment is observed for pH values around 6. This equilibrium is mainly controlled by the dissolution of iron sulfides and carbonate minerals. Consequently, the mobilization of inorganic contaminants as a function of pH remains very low (<0.1 wt%) for pH values above 6 and significantly increases for pH below these values. This research confirms the importance of a combined methodology for the intrinsic characterization of potential mobilization of contaminants in a stabilized sediment and for a better understanding of geochemical processes that affect contaminant fate, transformation, and transport in the subsurface environment. PMID:22961487

  19. EXPERIMENTAL STUDY HYDRAULIC ROUGHNESS FOR KAN TIN MAIN DRAINAGE CHANNEI IN HONG KONG

    Institute of Scientific and Technical Information of China (English)

    WANG Tao; YANG Kai-lin; GUO Xing-lei; XIE Sheng-zong; FU Hui; GUO Yong-xin

    2012-01-01

    The Kam Tin Main Drainage Channel (KTMDC) is an important river for the city drainage in Hong Kong.The roughness and its variations have an obvious effect on the flood control capacity and the flow capacity.So physical model tests are designed to study the KTMDC.Due to its complex channel structure,the tests are completed in two steps.In Step 1,the energy loss is measured along the main channel without inflows,with all inflows and outflows being sealed.In Step 2,all the inflow and outflow structures are measured,with the sealed inflows and outflows being opened on the basis of Step 1.In each step,two schemes are employed.One of the key issues is the choice of suitable materials to make the model's roughness similar to that of the prototype.According to the gravity similarity criterion,the 1:25 scale model is built,with the main channel made of Perspex.The facing slopes of the grasscrete and the stone masonry need to be roughened.A kind of the nylon net is selected to simulate the roughness of the stone masonry and the plastic lawn for the grasscrete facing slope.For the different structure reaches,the roughness coefficients are estimated based on the hydraulic theory.The rationality of the test results is verified in this study.The results of testing can provide a reliable basis for the renovation,the expansion,the optimization of this channel.

  20. A Laboratory Study of the Effects of Interbeds on Hydraulic Fracture Propagation in Shale Formation

    Directory of Open Access Journals (Sweden)

    Zhiheng Zhao

    2016-07-01

    Full Text Available To investigate how the characteristics of interbeds affect hydraulic fracture propagation in the continental shale formation, a series of 300 mm × 300 mm × 300 mm concrete blocks with varying interbeds, based on outcrop observation and core measurement of Chang 7-2 shale formation, were prepared to conduct the hydraulic fracturing experiments. The results reveal that the breakdown pressure increases with the rise of thickness and strength of interbeds under the same in-situ field stress and injection rate. In addition, for the model blocks with thick and high strength interbeds, the hydraulic fracture has difficulty crossing the interbeds and is prone to divert along the bedding faces, and the fracturing effectiveness is not good. However, for the model blocks with thin and low strength interbeds, more long branches are generated along the main fracture, which is beneficial to the formation of the fracture network. What is more, combining the macroscopic descriptions with microscopic observations, the blocks with thinner and lower strength interbeds tend to generate more micro-fractures, and the width of the fractures is relatively larger on the main fracture planes. Based on the experiments, it is indicated that the propagation of hydraulic fractures is strongly influenced by the characteristics of interbeds, and the results are instructive to the understanding and evaluation of the fracability in the continental shale formation.

  1. Study on stress characteristics of Francis hydraulic turbine runner based on two-way FSI

    Science.gov (United States)

    Zhu, W. R.; Xiao, R. F.; Yang, W.; Liu, J.; Wang, F. J.

    2012-11-01

    In recent years, cracking phenomenon occurs in many large-sized turbines both nationally and internationally, which has threatened the stable operation of hydraulic turbines. Consequently, Stress characteristics calculation and analysis of a Francis hydraulic turbine runner by application of fluid-structure interaction (FSI) technology become significantly important. In order to introduce two-way coupling technology to hydraulic machinery, two-way FSI technology is applied in this article to calculate and analyze stress characteristics. Through coordinate system transformation, the continuity equations and Navier-Stokes equations in the Cartesian coordinates system are firstly transformed to ALE coordinates system. The fluid field control equations are then constructed and discrete equations can be obtained by using flow-condition-based interpolation (FBIC-C). The structure static mechanics equations used are established in rotation coordinate system, and modeled with the finite method. Two-way coupling is computed by using iteration method. The fluid equations and structure equations are iterated until coupling coefficients converge. According to structure result, the maximum stress, displacement as well as its location can be found. As a result, the most easily wear position can be discovered which provides valuable basis for optimized design and stable operation of Francis hydraulic turbines. After comparing the results with that of one-way coupling, it is discovered that displacements is the key factors which affects the results of one-way and two-way coupling.

  2. Study on Control Strategy of Electro-Hydraulic Servo Loading System

    Directory of Open Access Journals (Sweden)

    Ju Tian

    2013-09-01

    Full Text Available Since extraneous torque is the key factor to affect the accuracy of electro-hydraulic servo loading system, the forming mechanism of extraneous torque was discussed in this work. And then several design methods of loading system controller based on modern control theory were introduced, such as internal model control, Cerebella model articulation control and adaptive backstepping control.

  3. Study on Control Strategy of Electro-Hydraulic Servo Loading System

    OpenAIRE

    Ju Tian

    2013-01-01

    Since extraneous torque is the key factor to affect the accuracy of electro-hydraulic servo loading system, the forming mechanism of extraneous torque was discussed in this work. And then several design methods of loading system controller based on modern control theory were introduced, such as internal model control, Cerebella model articulation control and adaptive backstepping control.

  4. Study on stress characteristics of Francis hydraulic turbine runner based on two-way FSI

    International Nuclear Information System (INIS)

    In recent years, cracking phenomenon occurs in many large-sized turbines both nationally and internationally, which has threatened the stable operation of hydraulic turbines. Consequently, Stress characteristics calculation and analysis of a Francis hydraulic turbine runner by application of fluid-structure interaction (FSI) technology become significantly important. In order to introduce two-way coupling technology to hydraulic machinery, two-way FSI technology is applied in this article to calculate and analyze stress characteristics. Through coordinate system transformation, the continuity equations and Navier-Stokes equations in the Cartesian coordinates system are firstly transformed to ALE coordinates system. The fluid field control equations are then constructed and discrete equations can be obtained by using flow-condition-based interpolation (FBIC-C). The structure static mechanics equations used are established in rotation coordinate system, and modeled with the finite method. Two-way coupling is computed by using iteration method. The fluid equations and structure equations are iterated until coupling coefficients converge. According to structure result, the maximum stress, displacement as well as its location can be found. As a result, the most easily wear position can be discovered which provides valuable basis for optimized design and stable operation of Francis hydraulic turbines. After comparing the results with that of one-way coupling, it is discovered that displacements is the key factors which affects the results of one-way and two-way coupling.

  5. STUDY ON AN OBJECTORIENTED FEATUREBASED CADOF HYDRAULIC MANIFOLD BLOCK

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The technique of objectoriented featurebased solid modeling and its application in the CAD of hydraulic manifold block (HMB) are discussed. The research can greatly improve the convenience and efficiency of product design for HMB, as well as for the other mechanical products.

  6. A Numerical Study on the Improvement of Suction Performance and Hydraulic Efficiency for a Mixed-Flow Pump Impeller

    OpenAIRE

    Sung Kim; Kyoung-Yong Lee; Jin-Hyuk Kim; Young-Seok Choi

    2014-01-01

    This paper describes a numerical study on the improvement of suction performance and hydraulic efficiency of a mixed-flow pump by impellers. The design of these impellers was optimized using a commercial CFD (computational fluid dynamics) code and DOE (design of experiments). The design variables of meridional plane and vane plane development were defined for impeller design. In DOE, variables of inlet part were selected as main design variables in meridional plane, and incidence angle was se...

  7. Mirror Advanced Reactor Study interim design report

    International Nuclear Information System (INIS)

    The status of the design of a tenth-of-a-kind commercial tandem-mirror fusion reactor is described at the midpoint of a two-year study. When completed, the design is to serve as a strategic goal for the mirror fusion program. The main objectives of the Mirror Advanced Reactor Study (MARS) are: (1) to design an attractive tandem-mirror fusion reactor producing electricity and synfuels (in alternate versions), (2) to identify key development and technology needs, and (3) to exploit the potential of fusion for safety, low activation, and simple disposal of radioactive waste. In the first year we have emphasized physics and engineering of the central cell and physics of the end cell. Design optimization and trade studies are continuing, and we expect additional modifications in the end cells to further improve the performance of the final design

  8. Mirror Advanced Reactor Study interim design report

    Energy Technology Data Exchange (ETDEWEB)

    1983-04-01

    The status of the design of a tenth-of-a-kind commercial tandem-mirror fusion reactor is described at the midpoint of a two-year study. When completed, the design is to serve as a strategic goal for the mirror fusion program. The main objectives of the Mirror Advanced Reactor Study (MARS) are: (1) to design an attractive tandem-mirror fusion reactor producing electricity and synfuels (in alternate versions), (2) to identify key development and technology needs, and (3) to exploit the potential of fusion for safety, low activation, and simple disposal of radioactive waste. In the first year we have emphasized physics and engineering of the central cell and physics of the end cell. Design optimization and trade studies are continuing, and we expect additional modifications in the end cells to further improve the performance of the final design.

  9. NATO Advanced Study Institute on Metal Hydrides

    CERN Document Server

    1981-01-01

    In the last five years, the study of metal hydrides has ex­ panded enormously due to the potential technological importance of this class of materials in hydrogen based energy conversion schemes. The scope of this activity has been worldwide among the industrially advanced nations. There has been a consensus among researchers in both fundamental and applied areas that a more basic understanding of the properties of metal/hydrogen syster;,s is required in order to provide a rational basis for the selection of materials for specific applications. The current worldwide need for and interest in research in metal hydrides indicated the timeliness of an Advanced Study Insti­ tute to provide an in-depth view of the field for those active in its various aspects. The inclusion of speakers from non-NATO coun­ tries provided the opportunity for cross-fertilization of ideas for future research. While the emphasis of the Institute was on basic properties, there was a conscious effort to stimulate interest in the applic...

  10. Study of bioleaching under different hydraulic retention time for enhancing the dewaterability of digestate.

    Science.gov (United States)

    Li, Linshuai; Gao, Jingqing; Zhu, Songfeng; Li, Yonghong; Zhang, Ruiqin

    2015-12-01

    Dewatering of kitchen waste digestate is a key problem to solve so as to increase the application of kitchen waste after anaerobic digestion. In this study, the effects of bioleaching under different hydraulic retention time (HRT = 2, 2.5, and 3 days) on dewaterability of kitchen waste digestate were evaluated. A 12-stage plug flow bioreactor with 180 L working volume was used for digestate bioleaching. The bioleached digestate under different HRTs were collected and dewatered by plate-and-frame filter press. The results showed that the moisture contents of digestate cakes were 67.87 % at 2 days of HRT, 58.06 % at 2.5 days of HRT, and 54.45 % at 3 days of HRT, respectively, indicating the longer the HRT, the lower the moisture content of filter cake. Balanced between the cost and practical need, 2.5 days can be used as the HRT in engineering application. Under the condition of HRT of 2.5 days, the pH, specific resistance to filtration (SRF), capillary suction time (CST), and sedimentation rate of digestate changed from the initial values of 8.08, 210.6 s, 23.4 × 10(12) m kg(-1) and 10 % to 3.21, 32.7 s, 2.44 × 10(12) m kg(-1) and 76.8 %, respectively. Based on the observations above, the authors conclude that bioleaching technology is an effective method to enhance digestate dewaterability and reduce the cost of subsequent reutilization. PMID:26298699

  11. Parametric studies on containment thermal hydraulic loads during high pressure melt ejection in a BWR

    Energy Technology Data Exchange (ETDEWEB)

    Silde, A.; Lindholm, I. [VTT Energy, Espoo (Finland)

    1997-12-01

    The containment thermal hydraulic loads during high pressure melt ejection in a Nordic BWR are studied parametrically with the CONTAIN and the MELCOR codes. The work is part of the Nordic RAK-2 project. The containment analyses were divided into two categories according to composition of the discharged debris: metallic and oxidic debris cases. In the base case with highly metallic debris, all sources from the reactor coolant system to the containment were based on the MELCOR/BH calculation. In the base case with the oxidic debris, the source data was specified assuming that {approx} 15% of the whole core material inventory and 34,000 kg of saturated water was discharged from the reactor pressure vessel (RPV) during 30 seconds. In this case, the debris consisted mostly of oxides. The highest predicted containment pressure peaks were about 8.5 bar. In the scenarios with highly metallic debris source, very high gas temperature of about 1900 K was predicted in the pedestal, and about 1400 K in the upper drywell. The calculations with metallic debris were sensititive to model parameters, like the particle size and the parameters, which control the chemical reaction kinetics. In the scenarios with oxidic debris source, the predicted pressure peaks were comparable to the cases with the metallic debris source. The maximum gas temperatures (about 450-500 K) in the containment were, however, significantly lower than in the respective metallic debris case. The temperatures were also insensitive to parametric variations. In addition, one analysis was performed with the MELCOR code for benchmarking of the MELCOR capabilities against the more detailed CONTAIN code. The calculations showed that leak tightness of the containment penetrations could be jeopardized due to high temperature loads, if a high pressure melt ejection occurred during a severe accident. Another consequence would be an early containment venting. (au). 28 refs.

  12. Study on thermal-hydraulic phenomena identification of passive heat removal facilities

    International Nuclear Information System (INIS)

    Recently, passive heat removal facilities have been integral features of new generation or future reactor designs worldwide. This is because the passive heat removal facilities depending on a natural force such as buoyancy can give much higher operational reliability compared to active heat removal facilities depending on pumped fluid flow and as a result they can decrease core damage frequency of a nuclear power plant drastically ever achievable before. Keeping pace with this global trend, SMART and APR+ reactors also have introduced passive heat removal features such as a passive residual heat removal system (PRHRS) and a passive auxiliary feed water system (PAFS) in their designs. Since many thermal-hydraulic (T-H) phenomena including steam condensation are involved during operation of the passive heat removal facilities, they ought to be properly simulated by T-H codes such as MARS-KS and RELAP5 in order to guarantee reliable safety analysis by these codes. Unfortunately, however, these T-H codes are not well validated with respect to phenomena related to passive heat removal mechanism because previous focus on these codes validation was mainly on the LB LOCA and resulting phenomena. To resolve this gap, Korea Institute of Nuclear Safety has initiated a research program on the development of safety analysis technology for passive heat removal facilities. The main target of this program is PRHRS and PAFS in SMART and APR+ reactors and through this program, validation of capability of existing T-H codes and improvement of codes regarding passive facilities analysis are to be sought. In part of this research, T-H phenomena important to passive heat removal facilities (PRHRS and PAFS) are investigated in the present study

  13. Thermo-hydro-mechanical simulation of a 3D fractured porous rock: preliminary study of coupled matrix-fracture hydraulics

    International Nuclear Information System (INIS)

    We present a problem involving the modeling of coupled flow and elastic strain in a 3D fractured porous rock, which requires prior homogenization (up-scaling) of the fractured medium into an equivalent Darcian anisotropic continuum. The governing equations form a system of PDE's (Partial Differential Equations) and, depending on the case being considered, this system may involve two different types of 'couplings' (in a real system, both couplings (1) and (2) generally take place): 1) Hydraulic coupling in a single (no exchange) or in a dual matrix-fracture continuum (exchange); 2) Thermo-Hydro-Mechanical interactions between fluid flow, pressure, elastic stress, strain, and temperature. We present here a preliminary model and simulation results with FEMLABR, for the hydraulic problem with anisotropic heterogeneous coefficients. The model is based on data collected at an instrumented granitic site (FEBEX project) for studying a hypothetical nuclear waste repository at the Grimsel Test Site in the Swiss Alps. (authors)

  14. The influence of a drop-hydraulic structure on the mountain stream channel regime - case study from the Polish Carpathians

    Directory of Open Access Journals (Sweden)

    Artur RADECKI-PAWLIK

    2013-06-01

    Full Text Available Basic hydraulic parameters such as shear stress, stream power, unit stream power and water velocities were calculated and measured within the region of a drop hydraulic structure erected on the Kasinczanka stream in the Polish Carpathians. Besides examining the hydrodynamics of the stream the study investigated also the distribution of grain size in the bed-load at the upstream and downstream aprons of the structure. It was revealed that grains deposited at the upstream apron were finer than those deposited at the downstream apron. At the same time, shear stresses and unit stream power values were found to be quite stable upstream of the drop structure, but to change significantly along the stream channel downstream of the structure’s energy dissipating pool

  15. NATO Advanced Study Institute on Superconducting Electronics

    CERN Document Server

    Nisenhoff, Martin; Superconducting Electronics

    1989-01-01

    The genesis of the NATO Advanced Study Institute (ASI) upon which this volume is based, occurred during the summer of 1986 when we came to the realization that there had been significant progress during the early 1980's in the field of superconducting electronics and in applications of this technology. Despite this progress, there was a perception among many engineers and scientists that, with the possible exception of a limited number of esoteric fundamental studies and applications (e.g., the Josephson voltage standard or the SQUID magnetometer), there was no significant future for electronic systems incorporating superconducting elements. One of the major reasons for this perception was the aversion to handling liquid helium or including a closed-cycle helium liquefier. In addition, many critics felt that IBM's cancellation of its superconducting computer project in 1983 was "proof" that superconductors could not possibly compete with semiconductors in high-speed signal processing. From our persp...

  16. The Hydraulic Jump: Finding Complexity in Turbulent Water

    Science.gov (United States)

    Vondracek, Mark

    2013-01-01

    Students who do not progress to more advanced science disciplines in college generally do not realize that seemingly simple physical systems are--when studied in detail--more complex than one might imagine. This article presents one such phenomenon--the hydraulic jump--as a way to help students see the complexity behind the seemingly simple, and…

  17. Overview of EPA's Approach to Developing Prospective Case Studies Technical Workshop: Case Studies to Assess Potential Impacts of Hydraulic Fracturing on Drinking Water Resources

    Science.gov (United States)

    One component of the United States Environmental Protection Agency's (EPA) study of the potential impacts of hydraulic fracturing on drinking water resources is prospective case studies, which are being conducted to more fully understand and assess if and how site specific hydrau...

  18. Temperature effect on the poro-mechanical or hydraulic behaviour of a carbonated rock and a mortar: experimental studies

    International Nuclear Information System (INIS)

    The main objective of this study is to evaluate the temperature effect on the hydraulic and poro-mechanical behaviour of a limestone. Many experimental tests (porosity and permeability measurements, uniaxial and hydrostatic compressions tests) were carried out in order to study the thermal treatments effect and so the thermal microcracking effect on rock behaviour. Moreover, an experimental device for permeability measurements under high temperatures (until 200 C) was realized. This experimental device permitted to study the permeability variation of the limestone under thermal stresses. Finally, the behaviour of cementitious materials was studied; the temperature effect on the permeability of a mortar was examined. (author)

  19. A COMPUTATIONAL STUDY OF THE ACTUATION SPEED OF THE HYDRAULIC CYLINDER UNDER DIFFERENT PORTS’ SIZES AND CONFIGURATIONS

    Directory of Open Access Journals (Sweden)

    M. O. ABDALLA

    2015-02-01

    Full Text Available The discharged oil from hydraulic cylinder, during its operation, is highly restricted by the small sized outlets. As a result, a back pressure builds up and the piston motion, therefore, is slowed down; the system pump has to do additional work to overcome this hydraulic resistance so as to preserve the required speed. In this study the possibility of improvement of the actuation speed of the hydraulic cylinders was investigated and analysed. Both a four-port cylinder and a resized-ports cylinder were proposed as fast cylinders. FLUENT 6.3 was used for the simulation of the oil flow field of the hydraulic cylinders. Results showed that relation between discharge flow and the outlets diameters is best described by a power law having coefficients partially depending on the system pressure. It had also shown that for any given total outlet area, the actuation speed of the single outlet cylinders is always higher than that of the double outlets cylinders. In one case where the total outlet area is 3.93E-05m2, the actuation speed of the single outlet cylinder is 21% higher than that of the double outlets cylinder; whereas, when doubling the total outlet area the different is reduced to just 6% . Resizing the outlet for small ports was more efficient than using multi-outlets; while for a large ports it shows no significant difference to use either one outlet port or multi-outlets. Both the solutions of resizing or ports addition need special valve to be fit to the cylinder so that the cylinder could be effectively operated under the control of the proportional valve.

  20. STUDY ON THE CONTROL SYSTEM OF HYDRAULIC MOMENT-ADJUSTED BRAKE FOR DOWNWARD BELT CONVEYOR

    Institute of Scientific and Technical Information of China (English)

    孟国营; 徐志强; 霍森; 方佳雨

    1997-01-01

    Having analyzed the drawbacks on the design of control system of hydraulic momentadjusted brake system, the author presents a closed loop control system in the process of start and braking of the conveyer. On the basis of the concept of the critical time and the critical acceleration and its deductions, the working mode of the conveyer can be identified and controlled in feedback, furthermore, thus realize the process of soft start. In the deceleration process, the author points out the problems that exist in the present control system and sets forward the control process that acted by the combined function of brake moment of motor and the drag torque of hydraulic brake at the beginning of deceleration, it will further improved reliability of conveyor system.

  1. Numerical and experimental study of hydraulic dashpot used in the shut-off rod drive mechanism of a nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Narendra K., E-mail: nksingh_chikki@yahoo.com [Division of Remote Handling and Robotics, Bhabha Atomic Research Centre, Mumbai 400085 (India); Badodkar, Deepak N. [Division of Remote Handling and Robotics, Bhabha Atomic Research Centre, Mumbai 400085 (India); Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094 (India); Singh, Manjit [Division of Remote Handling and Robotics, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2014-07-01

    Highlights: • Hydraulic dashpot performance is studied numerically as well as experimentally. • Instantaneous pressure built-up in the dashpot is mainly contributing for damping of freely falling shut-off rod at the end of its travel. • At elevated temperature, dashpot pressure does not reduce in proportion to the reduction in viscosity. • ‘C’ grove in the dashpot shaft flattens the pressure peak and shifts it toward the end of operation. - Abstract: Hydraulic dashpot design for shut-off rod drive mechanism application in a nuclear reactor has been analyzed both numerically and experimentally in this paper. Finite element commercial code COMSOL Multiphysics 4.3 has been used for numerical analysis. Experimental validation has been done at two different cases. Experimental test set-ups and hydraulic dashpot constructions have been described in detail. Various combinations of dashpot oil viscosity and clearance thickness have been analyzed. Important experimental results are also presented and discussed. Pressure distributions in the dashpot chambers obtained from COMSOL are given for both the set-ups. Numerical and experimental results are compared. Dashpot designs have been qualified after detailed analysis and testing on full-scale test stations simulating actual reactor conditions (except radiation)

  2. Classification Studies in an Advanced Air Classifier

    Science.gov (United States)

    Routray, Sunita; Bhima Rao, R.

    2016-01-01

    In the present paper, experiments are carried out using VSK separator which is an advanced air classifier to recover heavy minerals from beach sand. In classification experiments the cage wheel speed and the feed rate are set and the material is fed to the air cyclone and split into fine and coarse particles which are collected in separate bags. The size distribution of each fraction was measured by sieve analysis. A model is developed to predict the performance of the air classifier. The objective of the present model is to predict the grade efficiency curve for a given set of operating parameters such as cage wheel speed and feed rate. The overall experimental data with all variables studied in this investigation is fitted to several models. It is found that the present model is fitting good to the logistic model.

  3. The Pan American Advanced Studies Institute

    CERN Document Server

    Arous, Gérard; Ferrari, Pablo; Newman, Charles; Sidoravicius, Vladas; Vares, Maria

    2014-01-01

    This volume features selected and peer-reviewed articles from the Pan-American Advanced Studies Institute (PASI). The chapters are written by international specialists who participated in the conference. Topics include developments based on breakthroughs in the mathematical understanding of phenomena describing systems in highly inhomogeneous and disordered media, including the KPZ universality class (describing the evolution of interfaces in two dimensions), spin glasses, random walks in random environment, and percolative systems. PASI fosters a collaboration between North American and Latin American researchers and students. The conference that inspired this volume took place in January 2012 in both Santiago de Chile and Buenos Aires. Researchers and graduate students will find timely research in probability theory, statistical physics and related disciplines.

  4. Control definition study for advanced vehicles

    Science.gov (United States)

    Lapins, M.; Martorella, R. P.; Klein, R. W.; Meyer, R. C.; Sturm, M. J.

    1983-01-01

    The low speed, high angle of attack flight mechanics of an advanced, canard-configured, supersonic tactical aircraft designed with moderate longitudinal relaxed static stability (Static Margin, SM = 16% C sub W at M = 0.4) was investigated. Control laws were developed for the longitudinal axis (""G'' or maneuver and angle of attack command systems) and for the lateral/directional axes. The performance of these control laws was examined in engineering simulation. A canard deflection/rate requirement study was performed as part of the ""G'' command law evaluation at low angles of attack. Simulated coupled maneuvers revealed the need for command limiters in all three aircraft axes to prevent departure from controlled flight. When modified with command/maneuver limiters, the control laws were shown to be adequate to prevent aircraft departure during aggressive air combat maneuvering.

  5. Advanced Manned Launch System (AMLS) study

    Science.gov (United States)

    Ehrlich, Carl F., Jr.; Potts, Jack; Brown, Jerry; Schell, Ken; Manley, Mary; Chen, Irving; Earhart, Richard; Urrutia, Chuck; Randolph, Ray; Morris, Jim

    1992-01-01

    To assure national leadership in space operations and exploration in the future, NASA must be able to provide cost effective and operationally efficient space transportation. Several NASA studies and the joint NASA/DoD Space Transportation Architecture Studies (STAS) have shown the need for a multi-vehicle space transportation system with designs driven by enhanced operations and low costs. NASA is currently studying an advanced manned launch system (AMLS) approach to transport crew and cargo to the Space Station Freedom. Several single and multiple stage systems from air-breathing to all-rocket concepts are being examined in a series of studies potential replacements for the Space Shuttle launch system in the 2000-2010 time frame. Rockwell International Corporation, under contract to the NASA Langley Research Center, has analyzed a two-stage all-rocket concept to determine whether this class of vehicles is appropriate for the AMLS function. The results of the pre-phase A study are discussed.

  6. What does hydraulic tomography tell us about fractured geological media? A field study and synthetic experiments

    Science.gov (United States)

    Zha, Yuanyuan; Yeh, Tian-Chyi J.; Illman, Walter A.; Tanaka, Tatsuya; Bruines, Patrick; Onoe, Hironori; Saegusa, Hiromitsu

    2015-12-01

    Between 2005 and 2010, Japan Atomic Energy Agency conducted four long-term, independent pumping tests in a fractured granite formation at the Mizunami Underground Research Laboratory (MIU) site in Mizunami city, central Japan. During these tests, drawdowns were monitored at different depths along several deep boreholes. These tests become one of the few, if not the only, hydraulic tomographic survey conducted in the world over thousands of meters in a fractured geologic medium with several fault zones. We analyzed the drawdown-time data set associated with each pumping test independently, and then the data sets from all pumping tests jointly to derive the spatial distributions of hydraulic conductivity (K) and specific storage (Ss) of the medium. These estimated distributions revealed some large-scale high K and low K zones. While the low K zones corroborated well with known low permeable layers and fault based on geological investigations, there were no clear geological features that can be related to the large-scale high K zones. In order to understand and substantiate these high and low K zones, we simulated a hydraulic tomographic survey in a synthetic fractured aquifer, which bears similar geologic features (i.e., formations, fractures, and faults) at the MIU site, with exception that the hydraulic properties, fracture and fault distributions were known exactly. Results of the simulation show that not only are the identified high K zones related to fracture networks connected with pumping and observation locations of each pumping test but also their values reflect the degree of connectivity of the network. Afterward, we investigated the extent of the improvement of characterization of the fault and fractures through the use of deploying dense monitoring intervals and late-time flux measurements.

  7. Study on thermo-hydraulic behavior during reflood phase of a PWR-LOCA

    International Nuclear Information System (INIS)

    This paper describes thermo-hydraulic behavior during the reflood phase in a postulated large-break loss-of-coolant accident (LOCA) of a PWR. In order to better predict the reflood transient in a nuclear safety analysis specific analytical models have been developed for, saturated film boiling heat transfer in inverted slung flow, the effect of grid spacers on core thermo-hydraulics, overall system thermo-hydraulic behavior, and the thermal response similarity between nuclear fuel rods and simulated rods. A heat transfer correlation has been newly developed for saturated film boiling based on a 4 x 4-rod experiment conducted at JAERI. The correlation provides a good agreement with existing experiments except in the vicinity of grid spacer locations. An analytical model has then been developed addressing the effect of grid spacers. The thermo-hydraulic behavior near the grid spacers was found to be predicted well with this model by considering the breakup of droplets in dispersed flow and water accumulation above the grid spacers in inverted slung flow. A system analysis code has been developed which couples the one-dimensional core and multi-loop primary system component models. It provides fairly good agreement with system behavior obtained in a large-scale integral reflood experiment with active primary system components. An analytical model for the radial temperature distribution in a rod has been developed and verified with data from existing experiments. It was found that a nuclear fuel rod has a lower cladding temperature and an earlier quench time than an electrically heated rod in a typical reflood condition. (author)

  8. Study on blister of the coating on solid cantilevers of hydraulic supports for coal mining

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this work, blister of the Cu-Sn plus Cr coating on solid cantilevers of hydraulic supports for coal mining was investigated by hydrogen-charging, Devanathan-Stachurski method and electrochemical impedance spectroscopy (EIS) measurement. It was found that the permeation hydrogen during the pickling process and the electroplating process was responsible for the blisters. The residual tensile stress due to the machining process would increase the permeation hydrogen amount during pickling and electroplating processes.

  9. The Behaviour of Fracture Growth in Sedimentary Rocks: A Numerical Study Based on Hydraulic Fracturing Processes

    Directory of Open Access Journals (Sweden)

    Lianchong Li

    2016-03-01

    Full Text Available To capture the hydraulic fractures in heterogeneous and layered rocks, a numerical code that can consider the coupled effects of fluid flow, damage, and stress field in rocks is presented. Based on the characteristics of a typical thin and inter-bedded sedimentary reservoir, China, a series of simulations on the hydraulic fracturing are performed. In the simulations, three points, i.e., (1 confining stresses, representing the effect of in situ stresses, (2 strength of the interfaces, and (3 material properties of the layers on either side of the interface, are crucial in fracturing across interfaces between two adjacent rock layers. Numerical results show that the hydrofracture propagation within a layered sequence of sedimentary rocks is controlled by changing in situ stresses, interface properties, and lithologies. The path of the hydraulic fracture is characterized by numerous deflections, branchings, and terminations. Four types of potential interaction, i.e., penetration, arrest, T-shaped branching, and offset, between a hydrofracture and an interface within the layered rocks are formed. Discontinuous composite fracture segments resulting from out-of-plane growth of fractures provide a less permeable path for fluids, gas, and oil than a continuous planar composite fracture, which are one of the sources of the high treating pressures and reduced fracture volume.

  10. Advanced hybrid vehicle propulsion system study

    Science.gov (United States)

    Schwarz, R.

    1982-01-01

    Results are presented of a study of an advanced heat engine/electric automotive hybrid propulsion system. The system uses a rotary stratified charge engine and ac motor/controller in a parallel hybrid configuration. The three tasks of the study were (1) parametric studies involving five different vehicle types, (2) design trade-off studies to determine the influence of various vehicle and propulsion system paramaters on system performance fuel economy and cost, and (3) a conceptual design establishing feasibility at the selected approach. Energy consumption for the selected system was .034 1/km (61.3 mpg) for the heat engine and .221 kWh/km (.356 kWh/mi) for the electric power system over a modified J227 a schedule D driving cycle. Life cycle costs were 7.13 cents/km (11.5 cents/mi) at $2/gal gasoline and 7 cents/kWh electricity for 160,000 km (100,000 mi) life.

  11. Limits of downstream hydraulic geometry

    Science.gov (United States)

    Wohl, Ellen

    2004-10-01

    Adjustments to flow width, depth, and velocity in response to changes in discharge are commonly characterized by using downstream hydraulic geometry relationships. The spatial limits of these relationships within a drainage basin have not been systematically quantified. Where the erosional resistance of the channel substrate is sufficiently large, hydraulic driving forces presumably will be unable to adjust channel form. Data sets from 10 mountain rivers in the United States, Panama, Nepal, and New Zealand are used in this study to explore the limits of downstream hydraulic geometry relationships. Where the ratio of stream power to sediment size (Ω/D84) exceeds 10,000 kg/s3, downstream hydraulic geometry is well developed; where the ratio falls below 10,000 kg/s3, downstream hydraulic geometry relationships are poorly developed. These limitations on downstream hydraulic geometry have important implications for channel engineering and simulations of landscape change.

  12. A neutronics-thermal hydraulics model for preliminary studies on trade dynamics

    International Nuclear Information System (INIS)

    Full text of publication follows: The TRADE (TRIGA Accelerator Driven Experiment) is an experiment based on coupling of TRIGA RC-1 reactor, located at ENEA Casaccia Research Center, in subcritical core configuration obtained unloading fuel elements with a proton cyclotron by means of a neutron spallation target interface. This is one of the most important experiments to demonstrate the feasibility of the ADS concept at a power representative size. The experiments foreseen to be carried out, allow verifying the ADS procedures like start-up, shutdown, system dynamic behaviour vs. main system parameters like external source intensity, subcriticality level, etc. An analytical tool able to simulate the dynamic behaviour of the TRADE system can be directed to support the project (design of proton beam shut off, definition of reactivity control to guarantee subcritical margin, etc) as well as to safety analysis purpose. The RELAP5/PARCS code is considered one of the most suitable tools for studying the coupled neutronics-thermal-hydraulics problem in critical thermal reactors. In our case the capability of RELAP5 to treat light water reactors, like TRIGA, is now coupled with a PARCS version modified by ENEA to simulate the three-dimensional neutronics of a subcritical system. This work was carried out in the framework of the Italian research program TRASCO. The paper, starting from a satisfactory assessment of the PARCS modifications against a simple analytical solution of subcritical neutronics of TRADE (kinetics pseudo-potentials methods), presents the development of a quite detailed model for the coupled code able to evaluate the thermal feedback effects and to simulate the control rod action. Finally the transients calculated represent a wide range of both operational and incidental scenarios in order to obtain a first system response to a number of reactor elementary events at different subcritical levels. In particular, the operational transients investigated at

  13. Advances in soil-structure interaction studies

    International Nuclear Information System (INIS)

    It is utmost important that lifeline infrastructures (such as bridges, hospitals, power plants, dams etc.) are safe and functional during earthquakes as damage or collapse of these structures may have far reaching implications. A lifeline's failure may hamper relief and rescue operations required just after an earthquake and secondly its indirect economical losses may be very severe. Therefore, safety of these structures during earthquakes is vital. Further, damage to nuclear facilities during earthquake may lead to disaster. These structures should be designed adequately taking into account all the important issues. Soil-Structure Interaction (SSI) is one of the design issues, which is often overlooked and even in some cases ignored. The effects of dynamic SSI are well understood and practiced in the nuclear power industry (for large foundations of the nuclear containment structures) since sixties. However, in last decade, there are many advances in techniques of SSI and those need to be incorporated in practice. Failures of many structures occurred during the 1989 Loma Prieta and 1994 Northridge, California earthquakes and the 1995 Kobe, Japan earthquake due to SSI or a related issue. Many jetties had failed in Andaman and Nicobar islands due to Sumatra earthquake and ensuing tsunamis. It is because of this recent experience that the importance of SSI on dynamic response of structures during earthquakes has been fully realized. General belief that the SSI effects are always beneficial for the structure is not correct. Some cases have been presented where it is shown that SSI effects are detrimental for the stability of the structure. This paper addresses the effects of dynamic SSI on the response of the structures and explains its importance. Further advances in SSI studies have been discussed

  14. HYDRAULIC CHARACTERISTICS OF ACTIVATED SLUDGE SECONDARY CLARIFIERS

    Science.gov (United States)

    This study documented the hydraulic characteristics of typical activated sludge clarifiers. Modifications to the clarifier structures were made in an attempt to improve clarifier hydraulic characteristics and performance. Innovative fluorometric dye tracer studies were used to ob...

  15. 10MN/16MN数控高性能拉深液压机液压系统研究%Study on hydraulic system of 10MN/16MN high performance deep-drawing hydraulic press

    Institute of Scientific and Technical Information of China (English)

    叶臻; 王晋抚

    2013-01-01

    介绍了提高双动拉深液压机高性能的关键液压技术.分析了影响液压机快速平稳运行和压边滑块四角调平的原因,并对其液压回路分别进行了研究.解决了双动液压机速度慢和精度低等技术难题,有效提高了生产频率和综合性能.%The key technology for improving the high performance of deep-drawing hydraulic press has been introduced in the text. The reasons for influence of fast and smooth running of hydraulic press and four corners leveling control system for blank slider have been analyzed, and the hydraulic loops have been studied. Finally, the technical problems such as slow speed and low accuracy of double action hydraulic press have been solved, which effectively raise the production rate and comprehensive performance.

  16. Analysis of the three dimensional core kinetics NESTLE code coupling with the advanced thermo-hydraulic code systems, RELAP5/SCDAPSIM and its application to the Laguna Verde Central reactor

    International Nuclear Information System (INIS)

    The objective of the written present is to propose a methodology for the joining of the codes RELAP5/SCDAPSIM and NESTLE. The development of this joining will be carried out inside a doctoral program of Engineering in Energy with nuclear profile of the Ability of Engineering of the UNAM together with the National Commission of Nuclear Security and Safeguards (CNSNS). The general purpose of this type of developments, is to have tools that are implemented by multiple programs or codes such a that systems or models of the three-dimensional kinetics of the core can be simulated and those of the dynamics of the reactor (water heater-hydraulics). In the past, by limitations for the calculation of the complete answer of both systems, the developed models they were carried out for separate, putting a lot of emphasis in one but neglecting the other one. These methodologies, calls of better estimate, will be good to the nuclear industry to evaluate, with more high grades of detail, the designs of the nuclear power plant (for modifications to those already existent or for new concepts in the designs of advanced reactors), besides analysing events (transitory and have an accident), among other applications. The coupled system was applied to design studies and investigation of the Laguna Verde Nuclear power plant (CNLV). (Author)

  17. Modelling of Hydraulic Robot

    DEFF Research Database (Denmark)

    Madsen, Henrik; Zhou, Jianjun; Hansen, Lars Henrik

    1997-01-01

    This paper describes a case study of identifying the physical model (or the grey box model) of a hydraulic test robot. The obtained model is intended to provide a basis for model-based control of the robot. The physical model is formulated in continuous time and is derived by application of the l......This paper describes a case study of identifying the physical model (or the grey box model) of a hydraulic test robot. The obtained model is intended to provide a basis for model-based control of the robot. The physical model is formulated in continuous time and is derived by application...

  18. Combustion waves in hydraulically resisted systems.

    Science.gov (United States)

    Brailovsky, I; Kagan, L; Sivashinsky, G

    2012-02-13

    The effects of hydraulic resistance on the burning of confined/obstacle-laden gaseous and gas-permeable solid explosives are discussed on the basis of recent research. Hydraulic resistance is found to induce a new powerful mechanism for the reaction spread (diffusion of pressure) allowing for both fast subsonic as well as supersonic propagation. Hydraulic resistance appears to be of relevance also for the multiplicity of detonation regimes as well as for the transitions from slow conductive to fast convective, choked or detonative burning. A quasi-one-dimensional Fanno-type model for premixed gas combustion in an obstructed channel open at the ignition end is discussed. It is shown that, similar to the closed-end case studied earlier, the hydraulic resistance causes a gradual precompression and preheating of the unburned gas adjacent to the advancing deflagration, which leads (after an extended induction period) to a localized autoignition that triggers an abrupt transition from deflagrative to detonative combustion. In line with the experimental observations, the ignition at the open end greatly encumbers the transition (compared with the closed-end case), and the deflagration practically does not accelerate up to the very transition point. Shchelkin's effect, that ignition at a small distance from the closed end of a tube facilitates the transition, is described. PMID:22213662

  19. Case studies for solving the Saint-Venant equations using the method of characteristics: pipeline hydraulic transients and discharge propagation

    Science.gov (United States)

    Barros, R. M.; Tiago Filho, G. L.; dos Santos, I. F. S.; da Silva, F. G. B.

    2014-03-01

    Hydraulic transients occur during a change from one equilibrium state to another, for example, in flows. The pipeline project should provide the head and discharge in any operating states, e.g., sudden valve opening or closure. Among the various numerical approaches for the calculation of pipeline transients, the method of characteristics (MOC) is advantageous This study aims to present a hydraulic transitory study as MOC applications for solving the Saint- Venant equations in two case studies: 1) in a penstock of a small hydropower system as a simple pipeline in the case of valve-closure in the downstream boundary with a reservoir in the upstream boundary; and 2) for discharge propagation into a channel by velocity and depth of the flow channel along space evaluation. The main data for the first case study consisted of a design head that is 182 meters, a turbine discharge of 13.82 m3/s, a diameter of 4 meters and length pipe (penstock) of 2,152.50 meters. Regarding the second case study, the entry hydrogram was given to a rectangular channel with a width of 6.1 meters, length of 3,048 meters, slope of 0.0016 meters, and exhibited uniform flow with nominal depth of 2.44 meters. The characteristic curve of the discharge in the downstream extremity is Q = 158.(y - 3.25)32. The proposed methodology by Chaudry [5] concerning the development of hydrodynamic models was used. The obtained results for first case study showed that the simulated values for valve pressure while varying turning the valve between 4 and 12 seconds results in maximum values of pressures that oscillated between 219.97mca and 212.39 mca (4s) and 196.42mca and 190.86mca (12s). For the second case study, the values of discharge, velocity, and depth for x=0 and elapsed time of 850s were, respectively, 127.70m3/s, 3.87m/s, and 5.36m. For x=0 and an elapsed time of 1,230s, the values were 87.92m3/s, 4.49m/s, and 3.21m. Therefore, the MOC numerical approach has been confirmed to be useful for several

  20. Case studies for solving the Saint-Venant equations using the method of characteristics: pipeline hydraulic transients and discharge propagation

    International Nuclear Information System (INIS)

    Hydraulic transients occur during a change from one equilibrium state to another, for example, in flows. The pipeline project should provide the head and discharge in any operating states, e.g., sudden valve opening or closure. Among the various numerical approaches for the calculation of pipeline transients, the method of characteristics (MOC) is advantageous This study aims to present a hydraulic transitory study as MOC applications for solving the Saint- Venant equations in two case studies: 1) in a penstock of a small hydropower system as a simple pipeline in the case of valve-closure in the downstream boundary with a reservoir in the upstream boundary; and 2) for discharge propagation into a channel by velocity and depth of the flow channel along space evaluation. The main data for the first case study consisted of a design head that is 182 meters, a turbine discharge of 13.82 m3/s, a diameter of 4 meters and length pipe (penstock) of 2,152.50 meters. Regarding the second case study, the entry hydrogram was given to a rectangular channel with a width of 6.1 meters, length of 3,048 meters, slope of 0.0016 meters, and exhibited uniform flow with nominal depth of 2.44 meters. The characteristic curve of the discharge in the downstream extremity is Q = 158.(y – 3.25)32. The proposed methodology by Chaudry [5] concerning the development of hydrodynamic models was used. The obtained results for first case study showed that the simulated values for valve pressure while varying turning the valve between 4 and 12 seconds results in maximum values of pressures that oscillated between 219.97mca and 212.39 mca (4s) and 196.42mca and 190.86mca (12s). For the second case study, the values of discharge, velocity, and depth for x=0 and elapsed time of 850s were, respectively, 127.70m3/s, 3.87m/s, and 5.36m. For x=0 and an elapsed time of 1,230s, the values were 87.92m3/s, 4.49m/s, and 3.21m. Therefore, the MOC numerical approach has been confirmed to be useful for several

  1. Hydraulic interference test and tracer tests within the Braendan area, Finnsjoen study site

    International Nuclear Information System (INIS)

    The report covers the performance and interpretation of a series of hydraulic interference tests and a tracer test in fracture zone 2 within the Breandan area, Finnsjoen. The interference test were performed by pumping from isolated sections of one borehole and recording the resutling pressure changes in multiple-observation sections (generally five) in adjacent boreholes as well as in the pumping borehole. The tracer test was performed by pulse injection of tracers in isolated sections of the near-region observation boreholes and monitoring the break-trough of tracers in the pumping borehole. The interference tests showed that different response patterns were generated in the near-region and in the more distant region from the pumping borehole. In the near-region, primary responses in high-conductive, low-porosity flow paths between the boreholes generally dominate. The tracer test also indicates that the primary responses may be strongly influenced by local heterogeneities. At longer distances more averaged responses generally occurred with similar responses in the multiple-sections in the boreholes. The hydraulic interference test as well as the tracer test documented a very high transmissivity of zone 2, particularily in its upper part. The interference tests indicated hydraulic interaction between zone 2 and the over- and underlying rock. Zone 2 was found to be bounded and may be represented by a triangular-shaped area. Interflow to zone 2 occured during pumping, possibly via other fracture zones. Responses due to the pumping occurred at long distances (up to about 1.5 km) from the pumping borehole. A numerical model was used to simulate the responses of the interference tests. Good agreement was achieved between simulated and observed responses from the most distant boreholes but decreased agreement in the near-region boreholes. This fact was attributed to local heterogeneities in the near-region. (76 figs., 50 tabs., 36 refs.)

  2. Study of two-phase flow thermal-hydraulics during bottom reflooding of nuclear reactor cores

    International Nuclear Information System (INIS)

    Based on experimental observation of two-phase flow void fraction behavior during reflooding, and empirical correlation is proposed for fitting reflooding two-phase void fraction distribution. The empirical void fraction distribution is used to correct Hsu's transition boiling correlation for the effect of local void fraction. The UCLA Multi-Channel Reflood Model for analysis of reflooding thermal hydraulics is reviewed. Simple methods proposed for treatment of two-phase phenomena and core multi-dimensional effects are shown to be adequate. The model predictions are shown to be adequate. The model predictions are shown to compare well with experiment

  3. STUDY ON THE PERIODIC WATERHAMMER INITIATED BY A NOVEL HYDRAULIC SHOCK GENERATOR

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The hydrodynamic performances of a novel hydraulic shock generator are examined.The shock generator is designed to impose the strong power of waterhammer in mining industry.The experimental results show that the Waterhammer produced by the periodic fast switch of a flowing fluid has diferent features with that of a single closure observed by other researchers.In particular,the intensity of the waterhammer depends largely on the switch frequency due to the interaction of successive pressure waves.These flow transient phenomen a are theoretically proved by the simulation results based on the finite difference method of characteristics.

  4. The Hydraulic Project Włocławek: Design, Studies, Construction and Operation

    OpenAIRE

    Wojciech Majewski

    2015-01-01

    The Hydraulic Project Włocławek was commissioned in 1970 as the first barrage of the Lower Vistula Cascade (LVC). The purpose of the LVC was to create an important source of hydro-energy and inland navigation route connecting central Poland with the port city of Gdańsk. Along the Lower Vistula (LV) important cities and industrial centres are located. The Włocławek project still remains the only barrage on the LV thus creating a number of problems. The paper presents the basic hydrologic...

  5. Validation studies of thermal-hydraulic code for safety analysis of nuclear power plants

    International Nuclear Information System (INIS)

    The thesis gives an overview of the validation process for thermal-hydraulic system codes and it presents in more detail the assessment and validation of the French code CATHARE for VVER calculations. Three assessment cases are presented: loop seal clearing, core reflooding and flow in a horizontal steam generator. The experience gained during these assessment and validation calculations has been used to analyze the behavior of the horizontal steam generator and the natural circulation in the geometry of the Loviisa nuclear power plant. Large part of the work has been performed in cooperation with the CATHARE-team in Grenoble, France. (41 refs., 11 figs., 8 tabs.)

  6. Design Study on the Advanced Recycling Reactor

    International Nuclear Information System (INIS)

    The design study on the Advanced Recycling Reactor (ARR) has been conducted. This paper presents the pre-conceptual design of the ARR that is a loop-typed sodium cooled reactor with MOX fuel. International Nuclear Recycling Alliance (INRA) takes advantage of international experience and uses the design based on Japan Sodium-cooled Fast Reactor (JSFR) as reference for FOA studies of DOE in the U.S., because Japan has conducted R and Ds for the JSFR incorporating thirteen technology enhancements expected to improve safety, enhance economics, and increase reactor reliability. ARR's goal is to generate electricity while consuming fuel containing transuranics and to be cost-competitive with LWRs of similar size. INRA proposes 3 evolutions of the ARR; ARR1, a 500 MWe demonstration plant, online in 2025; ARR2, a 1,000 MWe commercial plant, online in 2035; ARR3, a 1,500 MWe full-scale commercial plant, online in 2050. INRA believes the scale-up factor of two is acceptable increase from manufacturing and licensing points of view. Major features of the ARR1 are the following: The reactor core of 70 cm high is working for a burner of TRU. The conversion ratio of fissile is set up less than 0.6 and the amount of burned TRU is 45-51 kg/TWeh. Decay heat can be removed by natural circulation to improve safety. The primary cooling system consists of two-loop arrangement and the integrated IHX/Pump to improve economics. The steam generator with the straight doublewalled tube is used to improve reliability. The capital cost, the construction schedule and regulatory and licensing schedule are estimated. Furthermore, the technology readiness level and the technology development roadmap are studied and identified to be ready for commercial deployment. (author)

  7. Mirror Advanced Reactor Study engineering overview

    International Nuclear Information System (INIS)

    The Mirror Advanced Reactor Study (MARS) was the first comprehensive conceptual design of a commercial tandem mirror reactor with thermal barriers. The design exploited the inherent attractive features of a tandem mirror: steady state operation, linear central cell, simple high performance blankets, low first wall heat fluxes, natural impurity diversion by the halo plasma, no driven plasma currents or associated disruptions, and direct conversion of the charged particle power lost out the ends. The study introduced new design concepts in high field magnets, neutral beams, ECRH systems, drift pumping, direct conversion, lithium-lead blankets and plant safety. The MARS design would produce 1200 MWsub(e) net and more than 1500 MWsub(e) gross from only 2600 MW of fusion power. This high efficiency is achieved through a combination of blanket design and direct conversion. Special emphasis was placed on fusion's potential for inherent safety, lower activation and simpler disposal of radioactive waste as compared with fission. The blanket has a very low tritium inventory, cannot melt in loss-of-coolant and/or loss-of-flow accidents and can be disposed of as low level waste subject to near-surface burial. MARS would produce busbar electricity at about 7 cents per kilowatthour (constant 1983 dollars). This value is near the upper end of the cost range for new generation capability being installed in the late 1980's. Significant cost reductions can be gained by further improvements in the engineering designs combined with a simplified end cell. The largest cost reductions from engineering can be attained through redesigned magnets, heat transport system and electrical system. The combination of engineering and physics improvements are projected to lower the cost of electricity by about 40% without sacrificing the environmental, safety and maintainability attributes of MARS. This work is now being pursued in the MINIMARS study. (orig.)

  8. NATO Advanced Study Institute on Spectroscopy

    Science.gov (United States)

    DiBartolo, Baldassare; Barnes, James (Technical Monitor)

    2001-01-01

    This booklet presents an account of the course 'Spectroscopy of Systems with Spatially Confined Structures' held in Erice-Sicily, Italy, from June 15 to June 30, 2001. This meeting was organized by the International School of Atomic and Molecular Spectroscopy of the 'Ettore Majorana' Centre for Scientific Culture. The purpose of this course was to present and discuss nanometer-scale physics, a rapidly progressing field. The top-down approach of semiconductor technology will soon meet the scales of the bottom-up approaches of supramolecular chemistry and of spatially localized excitations in ionic crystals. This course dealt with the fabrication, measurement and understanding of the relevant structures and brought together the scientific communities responsible for these development. The advances in this area of physics have already let to applications in optoelectronics and will likely lead to many more. The subjects of the course included spatially resolved structures such as quantum wells, quantum wires and quantum dots, single atoms and molecules, clusters, fractal systems, and the development of related techniques like near-field spectroscopy and confocal microscopy to study such systems.

  9. Study on thermal-hydraulic phenomena in porous media. Summarized report from 1997 Apr. to 2000 Mar

    International Nuclear Information System (INIS)

    This study deals with thermal-hydraulic phenomena in a porous blockage of a Fast Breeder Reactor. When foreign substances flow into the fuel subassembly with wire spacer, they would choke up the sub-channel and form a porous blockage. The objective of this study is to clarify the thermal-hydraulic phenomena in porous media and to develop the analytical method to predict the thermal-hydraulic field, deciding the maximum temperature on the fuel pin surface. This study is performed in cooperation with University of Tsukuba and Japan Nuclear Cycle Development Institute (JNC) from November 1997 to March 2000. This report describes the results for three years from April 1997 to March 2000. The visualization method using NaI solution as working fluid and Pyrex grass as structure was applicable to the porous media flow. When the concentration of NaI is 56.9 [wt%] in the solution, the refraction-rate corresponds to that of the Pyrex grass. The experiments to measure the velocity field inside and outside the blockage with Particle Image Velocimetry (PIV) analysis and Laser Doppler Velocimetry (LDV) were conducted. Moreover, we tried to measure the fluid temperature inside the blockage in the NaI solution, using Laser Induced Fluorescence (LIF) method. We checked the relation between the brightness of the fluorescence and solution temperature. And then, we revealed that the LIF method could be used even in the NaI solution. We also conducted the numerical analysis for the experiments. We confirmed that the calculation using the porous boby model is applicable to the analysis of the flow behavior around the porous blockage. (author)

  10. Single- and two-phase flow modeling for coupled neutronics / thermal-hydraulics transient analysis of advanced sodium-cooled fast reactors

    International Nuclear Information System (INIS)

    Nuclear power is nowadays in the front rank as regards helping to meet the growing worldwide energy demand while avoiding an excessive increase in greenhouse gas emissions. However, the operating nuclear power plants are mainly thermal-neutron reactors and, as such, can not be maintained on the basis of the currently identified uranium resources beyond one century at the present consumption rate. Sustainability of nuclear power thus involves closure of the fuel cycle through breeding. With a uranium-based fuel, breeding can only be achieved using a fast-neutron reactor. Sodium-cooled fast reactor (SFR) technology benefits from 400 reactor-years of accumulated experience and is thus a prime candidate for the implementation of so-called Generation-IV nuclear energy systems. In this context, the safety demonstration of SFRs remains a major Research and Development related issue. The current research aims at the development of a computational tool for the in-depth understanding of SFR core behaviour during accidental transients, particularly those including boiling of the coolant. An accurate modelling of the core physics during such transients requires the coupling between 3D neutron kinetics and thermal-hydraulics in the core, to account for the strong interactions between the two-phase coolant flow and power variations caused by the sodium void effect. The present study is specifically focused upon models for the representation of sodium two-phase flow. The extension of the thermal-hydraulics TRACE code, previously limited to the simulation of single-phase sodium flow, has been carried out through the implementation of equations-of-state and closure relations specific to sodium. The different correlations have then been implemented as options. From the validation study carried out, it has been possible to recommend a set of models which provide satisfactory results, while considering annular flow as the dominant regime up to dryout and a smooth breakdown of the

  11. Performing sensitivity studies of fracture network parameters in order to obtain effective hydraulic properties for porous medium models

    International Nuclear Information System (INIS)

    Within the scope of a R and D project concerning long term safety assessments for waste disposal in deep mines, GRS used the fracture network code NAPSAC 4.0. The objective was to obtain effective hydraulic properties calculated with statistically generated small scale fracture network models as data input for large scale effective porous medium models. The latter were used for far field calculations. The results of the fracture network parameter studies show the possibility to adjust the field investigations according to the parameter sensitivity and to judge the reliability of subsequent fracture network simulations. (author)

  12. Design and Construction of Experiment for Direct Electron Irradiation of Uranyl Sulfate Solution: Bubble Formation and Thermal Hydraulics Studies

    Energy Technology Data Exchange (ETDEWEB)

    Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States); Gromov, Roman [Argonne National Lab. (ANL), Argonne, IL (United States); Makarashvili, Vakho [Argonne National Lab. (ANL), Argonne, IL (United States); Heltemes, Thad [Argonne National Lab. (ANL), Argonne, IL (United States); Sun, Zaijing [Argonne National Lab. (ANL), Argonne, IL (United States); Wardle, Kent E. [Argonne National Lab. (ANL), Argonne, IL (United States); Bailey, James [Argonne National Lab. (ANL), Argonne, IL (United States); Quigley, Kevin [Argonne National Lab. (ANL), Argonne, IL (United States); Stepinski, Dominique [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, George [Argonne National Lab. (ANL), Argonne, IL (United States)

    2014-10-01

    Argonne is assisting SHINE Medical Technologies in developing SHINE, a system for producing fission-product 99Mo using a D/T-accelerator to produce fission in a non-critical target solution of aqueous uranyl sulfate. We have developed an experimental setup for studying thermal-hydraulics and bubble formation in the uranyl sulfate solution to simulate conditions expected in the SHINE target solution during irradiation. A direct electron beam from the linac accelerator will be used to irradiate a 20 L solution (sector of the solution vessel). Because the solution will undergo radiolytic decomposition, we will be able to study bubble formation and dynamics and effects of convection and temperature on bubble behavior. These experiments will serve as a verification/ validation tool for the thermal-hydraulic model. Utilization of the direct electron beam for irradiation allows homogeneous heating of a large solution volume and simplifies observation of the bubble dynamics simultaneously with thermal-hydraulic data collection, which will complement data collected during operation of the miniSHINE experiment. Irradiation will be conducted using a 30-40 MeV electron beam from the high-power linac accelerator. The total electron-beam power will be 20 kW, which will yield a power density on the order of 1 kW/L. The solution volume will be cooled on the front and back surfaces and central tube to mimic the geometry of the proposed SHINE solution vessel. Also, multiple thermocouples will be inserted into the solution vessel to map thermal profiles. The experimental design is now complete, and installation and testing are in progress.

  13. Fast neutron breeder reactor Rapsodie - situation of physics, hydraulic, thermal and dynamics studies and studies of stability early in 1963

    International Nuclear Information System (INIS)

    Early in 1963, it was necessary to make a choice among the two fuels examined for Rapsodie: the UPuMo alloy with double cladding, Nb and stainless steel, and the UO2-PuO2 mix oxide. This report presents the results of the studies effected with the two types of fuel. We reconsider at first the different models which have been studied and we give a detailed description of the alloy and oxide cores as they are envisaged early in 1963. We give then the most important physics performances of the two cores: neutron flux and spectrum, reactivity of the compensation find safety rods, neutrons balance, specific power, effective fraction of delayed neutrons, lifetime of the prompt neutrons, reactivity coefficient. We describe the hydraulic studies and experiments which have been done concerning the two cores. We discuss the criteria adopted as basis for the flow calculations. We give the results of pressure drop and sub-assembly lifting, force measurements, and vibration and pin flow distribution experiments. We discuss the constants utilized for the thermal calculations and we give the temperatures of sodium and alloy or oxide fuel, the temperature increases due to the hot points, and the limitation of the oxide fuel burn-up, originated by the pressure of the fission gases. We treat the hypotheses having been utilized for the dynamics calculations and we describe the different accidents which have been studied. We give the results of the calculations for every accident and each fuel, and we show fuel melting or sodium boiling can be avoided, even in case of the most pessimistic hypotheses, by modifying reactor characteristics (shim-rod reactivity or power of the reactor with only one cooling circuit). The reactor stability has been evaluated with the hypotheses utilized for the dynamics calculations, except of the Doppler coefficient which was intentionally increased. We show that the alloy and oxide cores are stable for every envisaged reactor power. (authors)

  14. A hydraulic tomography approach coupling travel time inversion with steady shape analysis based on aquifer analogue study in coarsely clastic fluvial glacial deposit

    Science.gov (United States)

    Hu, R.; Brauchler, R.; Herold, M.; Bayer, P.; Sauter, M.

    2009-04-01

    the hydraulic gradient does not. By this trick, transient data can be analyzed with the computational efficiency of a steady state model, which proceeds hundreds of times faster than transient models. Finally, a specific storage distribution can be calculated from the diffusivity and hydraulic conductivity reconstructions derived from travel time and steady shape inversion. The groundwork of this study is the aquifer-analogue study from BAYER (1999), in which six parallel profiles of a natural sedimentary body with a size of 16m x 10m x 7m were mapped in high resolution with respect to structural and hydraulic parameters. Based on these results and using geostatistical interpolation methods, MAJI (2005) designed a three dimensional hydraulic model with a resolution of 5cm x 5cm x 5cm. This hydraulic model was used to simulate a large number of short term pumping tests in a tomographical array. The high resolution parameter reconstructions gained from the inversion of simulated pumping test data demonstrate that the proposed inversion scheme allows reconstructing the individual architectural elements and their hydraulic properties with a higher resolution compared to conventional hydraulic and geological investigation methods. Bayer P (1999) Aquifer-Analog-Studium in grobklastischen braided river Ablagerungen: Sedimentäre/hydrogeologische Wandkartierung und Kalibrierung von Georadarmessungen, Diplomkartierung am Lehrstuhl für Angewandte Geologie, Universität Tübingen, 25 pp. Maji, R. (2005) Conditional Stochastic Modelling of DNAPL Migration and Dissolution in a High-resolution Aquifer Analog, Ph.D. thesis at the University of Waterloo, 187 pp.

  15. Study on recriticality of fuel debris during hypothetical severe accidents in the Advanced Neutron Source reactor

    International Nuclear Information System (INIS)

    A study has been performed to measure the potential of recriticality during hypothetical severe accident in Advanced Neutron Source (ANS). For the lumped debris configuration in the Reactor Coolant System (RCS), as found in the previous study, recriticality potential may be very low. However, if fuel debris is dispersed and mixed with heavy water in RCS, recriticality potential has been predicted to be substantial depending on thermal-hydraulic conditions surrounding fuel debris mixture. The recriticality potential in RCS is substantially reduced for the three element core design with 50% enrichment. Also, as observed in the previous study, strong dependencies of keff on key thermal hydraulic parameters are shown. Light water contamination is shown to provide a positive reactivity, and void formation due to boiling of mixed water provides enough negative reactivity and to bring the system down to subcritical. For criticality potential in the subpile room, the lumped debris configuration does not pose a concern. Dispersed configuration in light water pool of the subpile room is also unlikely to result in criticality. However, if the debris is dispersed in the pool that is mixed with heavy water, the results indicate that a substantial potential exists for the debris to reach the criticality. However, if prompt recriticality disperses the debris completely in the subpile room pool, subsequent recriticality may be prevented since neutron leakage effects become large enough

  16. Advanced SFR Concept Design Studies at KAERI

    International Nuclear Information System (INIS)

    Advanced SFR design concepts have been developed which satisfy the Gen IV technology goals at KAERI. Two types of reactor core were developed for breakeven and TRU burner and both cores do not have blankets to enhance proliferation resistance. The Advanced SFR is a pool-type reactor that improves system safety through slow system transients. The heat transport system adopts two double wall tube Steam Generators and a passive Residual Heat Removal System PDRC. To secure the economic competitiveness of an SFR, the diameter of the reactor vessel of the Advanced SFR is designed to be 14.5 m, which is a very compact size compared to other designs. Also, various R and D activities have been performed in order to prepare some analysis tools and to support the development of design concepts. (author)

  17. Neoadjuvant chemotherapy in advanced epithelial ovarian cancer: A survival study

    OpenAIRE

    Upasana Baruah; Debabrata Barmon; Amal Chandra Kataki; Pankaj Deka; Munlima Hazarika; Bhargab J Saikia

    2015-01-01

    Context: Patients with advanced ovarian cancer have a poor prognosis in spite of the best possible care. Primary debulking surgery has been the standard of care in advanced ovarian cancer; however, it is associated with high mortality and morbidity rates as shown in various studies. Several studies have discussed the benefit of neoadjuvant chemotherapy in patients with advanced ovarian cancer. Aims: This study aims to evaluate the survival statistics of the patients who have been managed with...

  18. Hydraulic manipulator

    International Nuclear Information System (INIS)

    Successful operation of nuclear plant is largely dependent on safe handling of radio-active material. In order to reduce this handling problem and minimise the exposure of radiation, various handling equipment and manipulators have been developed according to the requirements. Manufacture of nuclear fuel, which is the most important part of the nuclear industry, involves handling of uranium ingots weighing approximately 250 kg. This paper describes a specially designed hydraulic manipulator for handling of the ingots in a limited space. It was designed to grab and handle the ingots in any position. This has following drive motions: (1)gripping and releasing, (2)lifting and lowering (z-motion), (3)rotation about the horizontal axis (azimuth drive), (4)rotation about the job axis, and (5)rotation about the vertical axis. For horizontal motion (X and Y axis motion) this equipment is mounted on a motorised trolley, so that it can move inside the workshop. For all drives except the rotation about the job axis, hydraulic cylinders have been used with a battery operated power pack. Trolley drive is also given power from same battery. This paper describes the design aspects of this manipulator. (author). 4 figs

  19. Design study on the Advanced Recycling Reactor

    International Nuclear Information System (INIS)

    Full text: The design study on the Advanced Recycling Reactor (ARR) has been conducted. This paper presents the pre-conceptual design of the ARR that is a loop-typed sodium cooled reactor with MOX fuel. International Nuclear Recycling Alliance (INRA) takes advantage of international experience and uses the design based on Japan Sodium-cooled Fast Reactor (JSFR) as reference for FOA studies of US DOE, because Japan has conducted R and Ds for the JSFR incorporating thirteen technology enhancements expected to improve safety, enhance economics, and increase reactor reliability. The targets of the ARR are to generate electricity while consuming fuel containing transuranics and to attain cost competitiveness with the similar sized LWRs. INRA proposes 3 evolutions of the ARR; ARR1, a 500 MWe demonstration plant, online in 2025; ARR2, a 1,000 MWe commercial plant, online in 2035; ARR3, a 1,500 MWe full-scale commercial plant, online in 2050. INRA believes the scale-up factor of two is acceptable increase from manufacturing and licensing points of view. Major features of the ARR1 are the following: The reactor core is 70cm high and the volume fraction of fuel is approximately 32%. The conversion ratio of fissile is set up less than 0.6 and the amount of burned TRU is 45-51 kg/TWeh.Decay heat can be removed by natural circulation to improve safety. The primary cooling system consists of two-loop arrangement and the integrated IHX/Pump to improve economics. The steam generator with the straight double-walled tube is used to improve reliability. The ARR1 is co-located with a recycling facility. The overall plant facility arrangement is planned assuming to be constructed and installed in an inland area. The plant consists of a reactor building (including reactor auxiliary facilities and electrical/control systems), a turbine building, and a recycling building. The volume of the reactor building will be approximately 180,000 m3. The capital cost for the ARR1 and the ARR2 are

  20. Hydraulic Stability of Accropode Armour

    DEFF Research Database (Denmark)

    Jensen, T.; Burcharth, H. F.; Frigaard, Peter

    The present report describes the hydraulic model tests of Accropode armour layers carried out at the Hydraulics Laboratory at Aalborg University from November 1995 through March 1996. The objective of the model tests was to investigate the hydraulic stability of Accropode armour layers......, and to assess the influence of core permeability on the hydraulic stability of Accropodes. Two structures were examined, one with a relatively permeable core and one with a relatively impermeable core. In November/December 1995, Ph.D.-student Marten Christensen carried out the model tests on the structure...... with permeable core (crushed granite with a gradation of 5-8 mm). The outcome of this study is described in "Hydraulic Stability of Single-Layer Dolos and Accropode Armour Layers" by Christensen & Burcharth (1995). In January/February 1996, Research Assistant Thomas Jensen carried out a similar study...

  1. Feasibility study for objective oriented design of system thermal hydraulic analysis program

    International Nuclear Information System (INIS)

    The system safety analysis code, such as RELAP5, TRAC, CATHARE etc. have been developed based on Fortran language during the past few decades. Refactoring of conventional codes has been also performed to improve code readability and maintenance. However the programming paradigm in software technology has been changed to use objects oriented programming (OOP), which is based on several techniques, including encapsulation, modularity, polymorphism, and inheritance. In this work, objective oriented program for system safety analysis code has been tried utilizing modernized C language. The analysis, design, implementation and verification steps for OOP system code development are described with some implementation examples. The system code SYSTF based on three-fluid thermal hydraulic solver has been developed by OOP design. The verifications of feasibility are performed with simple fundamental problems and plant models. (author)

  2. An experimental study of the dual-loop control of electro-hydraulic load simulator (EHLS)

    Institute of Scientific and Technical Information of China (English)

    Wang Chengwen; Jiao Zongxia; Wu Shuai; Shang Yaoxing

    2013-01-01

    This paper investigates motion coupling disturbance (the so called surplus torque) in the hardware-in-the-loop (HIL) experiments. The‘‘velocity synchronization scheme’’ was proposed by Jiao for an electro-hydraulic load simulator (EHLS) in 2004. In some situations, however, the scheme is limited in the implementation for certain reasons, as is the case when the actuator’s valve signal is not available or it is seriously polluted by noise. To solve these problems, a ‘‘dual-loop scheme’’ is developed for EHLS. The dual-loop scheme is a combination of a torque loop and a position synchronization loop. The role of the position synchronization loop is to decouple the motion disturbance caused by the actuator system. To verify the feasibility and effectiveness of the proposed scheme, extensive simulations are performed using AMESim. Then, the performance of the developed method is validated by experiments.

  3. Study on the impeller hydraulic performance for the contra-rotating axial flow pump

    International Nuclear Information System (INIS)

    This paper discusses the design method and performance of the front and rear impellers of the contra-rotating axial flow pump. A definition of specific speed has been given. The design head of rear impeller is suggested to increase appropriately. By analyzing the inlet and outlet velocity triangles of the twin impellers in detail under design and off-design point, the paper gives a matching condition and formulas for working out the two triangles. Based on the velocity triangles and 'lift method', the geometric parameters of the twin impellers have been designed, the results have been analyzed qualitatively, and the hydraulic performance has been predicted. A practical design shows that at the same design head of the twin impellers, the relative velocity at the middle of inlet and outlet of rear impeller are larger than that of the front impeller, while the stagger angle is smaller and the head curve is much steeper

  4. Thermal-hydraulic study of a high conversion light water reactor

    International Nuclear Information System (INIS)

    A high conversion light water reactor (HCLWR) has been developed at JAERI to improve fuel utilization. The fuel assemblies of the HCLWR have a triangular tight rod lattice in order to attain a high conversion ratio by reducing the moderator-to-fuel volume ratio. The tight lattice core leads to some thermal-hydraulic problems peculiar to the HCLWR. Therefore, experiments on steady-state and transient critical heat flux (CHF), turbulent mixing, bundle pressure drop, fuel vibration induced by fluid flow and reflood cooling have been performed to obtain data base and develop evaluation methods for the HCLWR. The evaluation methods were applied to a JAERI-proposed double-flat-core type HCLWR. Under the operational condition, the minimum allowable DNBR criterion is satisfied and the bundle pressure drop and flow-induced vibration and displacement of the fuel rod are within the design limit of a current LWR. Safety analyses under vital conditions such as the large break loss-of-coolant accident (LOCA), small break LOCA, pump trip accident, locked rotor accident, anticipated transient without scram (ATWS) induced by station blackout and control rod cluster ejection accident have been performed with a best-estimate REFLA/TRAC code. The results showed that the present HCLWR meets the current safety criteria for a LWR. The design features such as the large water inventory in the upper plenum, short core length, low axial peaking factor and negative void and coolant temperature reactivity coefficients contribute to the thermal-hydraulic feasibility of the double-flat-core type HCLWR. (author)

  5. Thermal-Hydraulics Study of a 75 kWth Aqueous Homogeneous Reactor for 99Mo Production

    Directory of Open Access Journals (Sweden)

    Daniel Milian Pérez

    2015-01-01

    Full Text Available Tc99m is a very useful radioisotope, which is used in nearly 80% of all nuclear medicine procedures. Tc99m is produced from 99Mo decay. A potentially advantageous alternative to meeting current and future demand for 99Mo is the use of Aqueous Homogeneous Reactors (AHR. In this paper, a thermal-hydraulics study of the core of a 75 kWth AHR conceptual design based on the ARGUS reactor for 99Mo production is presented. As the ARGUS heat removal systems were designed for working at 20 kWth, the main objective of the thermal-hydraulics study was evaluating the heat removal systems in order to show that sufficient cooling capacity exists to prevent fuel solution overheating. The numerical simulations of an AHR model were carried out using the Computational Fluid Dynamic (CFD code ANSYS CFX 14. Evaluation shows that the ARGUS heat removal systems working at 75 kWth are not able to provide sufficient cooling capacity to prevent fuel solution overheating. To solve this problem, the number of coiled cooling pipes inside the core was increased from one to five. The results of the CFD simulations with this modification in the design show that acceptable temperature distributions can be obtained.

  6. Airborne laser scanning terrain and land cover models as basis for hydrological and hydraulic studies

    International Nuclear Information System (INIS)

    The high level of topographic details is the main advantage using ALS data, which also causes many problems in different hydrological and hydraulic applications. So, the detailed topographic information can have a negative impact on the quality of hydrological and hydraulic applications. Besides the high level of geometric details, the intensity values as well as the full vertical point distribution within the 3D point cloud is available. It is shown, based on selected applications, how to minimize the negative effects of topographic details and how to extract specific parameters for hydrological and hydraulic purposes directly from ALS data by using geoinformation and remote sensing methods. The main focus is on improving existing methods to extract hydraulic and hydrological features from the ALS data with a high level of automatization. The first part deals with Laser Remote Sensing technology in general. Besides the measurement principles, different laser platforms and common gridded derivatives are presented. Finally, recent technology trends are discussed. Within the first chapter a workflow to optimize a 1m-DTM for drainage network delineation is presented. Mostly coarse DTMs, smoothed by using average filters, are used. Where detailed topographic features and roads are removed by the DTM smoothing. Therefore, the 1m spatial resolution of the ALS DTM is no longer available for the drainage delineation. By removing anthropogenic structures, mainly roads, a conditioned DTM is produced without the negative influences of the roads from the original 1m-DTM on the flow accumulation. The resulting drainage network computed on the conditioned 1m-DTM show an increase in delineation accuracy of up to 9% in correctness and completeness compared to the original 1m-DTM or a coarse resolution 5m-DTM as basis for flow accumulation. The second methodological chapter is about the delineation of water surface areas using ALS geometric and radiometric data derived from the

  7. Advanced nuclear systems. Review study; Fortgeschrittene Nuklearsysteme. Review Study

    Energy Technology Data Exchange (ETDEWEB)

    Liebert, Wolfgang; Glaser, Alexander; Pistner, Christoph [Interdisziplinaere Arbeitsgruppe Naturwissenschaft, Technik und Sicherheit (IANUS), Darmstadt University of Technology, Hochschulstrasse 10, D-64289 Darmstadt (Germany); Baehr, Roland; Hahn, Lothar [Institute for applied ecology (Oeko-Institut), Elisabethenstrasse 55-57, D-64283 Darmstadt (Germany)

    1999-04-01

    The task of this review study is to from provide an overview of the developments in the field of the various advanced nuclear systems, and to create the basis for more comprehensive studies of technology assessment. In an overview the concepts for advanced nuclear systems pursued worldwide are subdivided into eight subgroups. A coarse examination raster (set pattern) is developed to enable a detailed examination of the selected systems. In addition to a focus on enhanced safety features, further aspects are also taken into consideration, like the lowering of the proliferation risk, the enhancement of the economic competitiveness of the facilities and new usage possibilities (for instance concerning the relaxation of the waste disposal problem or the usage of alternative fuels to uranium). The question about the expected time span for realization and the discussion about the obstacles on the way to a commercially usable reactor also play a substantial role as well as disposal requirements as far as they can be presently recognized. In the central chapter of this study, the documentation of the representatively selected concepts is evaluated as well as existing technology assessment studies and expert opinions. In a few cases where this appears to be necessary, according technical literature, further policy advisory reports, expert statements as well as other relevant sources are taken into account. Contradictions, different assessments and dissents in the literature as well as a few unsettled questions are thus indicated. The potential of advanced nuclear systems with respect to economical and societal as well as environmental objectives cannot exclusively be measured by the corresponding intrinsic or in comparison remarkable technical improvements. The acceptability of novel or improved systems in nuclear technology will have to be judged by their convincing solutions for the crucial questions of safety, nuclear waste and risk of proliferation of nuclear weapons

  8. Thermal hydraulic tests for reactor safety system -Research on the improvement of nuclear safety-

    International Nuclear Information System (INIS)

    The present research aims at the development of the thermal hydraulic verification test technology for the reactor safety system of the conventional and advanced nuclear power plant and the development of the advanced thermal hydraulic measuring techniques. (Author)

  9. Computational study on the thermal hydraulic performance of new printed circuit heat exchanger for supercritical carbon dioxide

    International Nuclear Information System (INIS)

    Three-dimensional numerical analysis was performed to study thermal-hydraulic (heat transfer and pressure drop) characteristics of supercritical CO2 flow in new Printed Circuit Heat Exchanger (PCHE) using commercial CFD code, Fluent 6.3. To validate the accuracy of numerical analysis, computational analysis for conventional zigzag channel PCHE was performed and compared with previous experimental data. Maximum deviation of in-outlet temperature difference and pressure drop from published experimental data is about 10%. A new PCHE has been designed to optimize thermal-hydraulic performance of PCHE. The new PCHE model has several airfoil shape fins, which are designed to streamlined shape. Computational results showed that in the airfoil shape fin PCHE, total heat transfer rate per unit volume was almost same with zigzag channel PCHE and the pressure drop was reduced to one-twentieth of that in zigzag channel PCHE. In airfoil shape fin PCHE, the enhancement of heat transfer area and the uniform flow configuration contributed to obtain the same heat transfer performance with zigzag channel PCHE. The decrease of pressure drop in airfoil shape fin PCHE was caused by suppressing generation of separated flow owing to streamlined shape of airfoil fins. (author)

  10. Beneficial effects on water management of simple hydraulic structures in wetland systems: the Vallevecchia case study, Italy.

    Science.gov (United States)

    Carrer, G M; Bonato, M; Smania, D; Barausse, A; Comis, C; Palmeri, L

    2011-01-01

    Conflicting water uses in coastal zones demand integrated approaches to achieve sustainable water resources management, protecting water quality while allowing those human activities which rely upon aquatic ecosystem services to thrive. This case study shows that the creation and simple management of hydraulic structures within constructed wetlands can markedly reduce the non-point pollution from agriculture and, simultaneously, benefit agricultural activities, particularly during hot and dry periods. The Vallevecchia wetland system is based on a reclaimed 900 ha-large drainage basin in Northern Italy, where droughts recently impacted agriculture causing water scarcity and saltwater intrusion. Rainwater and drained water are recirculated inside the system to limit saltwater intrusion, provide irrigation water during dry periods and reduce the agricultural nutrient loads discharged into the bordering, eutrophic Adriatic Sea. Monitoring (2003-2009) of water quality and flows highlights that the construction (ended in 2005) of a gated spillway to control the outflow, and of a 200,000 m3 basin for water storage, dramatically increased the removal of nutrients within the system. Strikingly, this improvement was achieved with a minimal management effort, e.g., each year the storage basin was filled once: a simple management of the hydraulic structures would greatly enhance the system efficiency, and store more water to irrigate and limit saltwater intrusion. PMID:22053478

  11. Optimizing the Use of LiDAR for Hydraulic and Sediment Transport Model Development: Case Studies from Marin and Sonoma Counties, CA

    Science.gov (United States)

    Kobor, J. S.; O'Connor, M. D.; Sherwood, M. N.

    2013-12-01

    Effective floodplain management and restoration requires a detailed understanding of floodplain processes not readily achieved using standard one-dimensional hydraulic modeling approaches. The application of more advanced numerical models is, however, often limited by the relatively high costs of acquiring the high-resolution topographic data needed for model development using traditional surveying methods. The increasing availability of LiDAR data has the potential to significantly reduce these costs and thus facilitate application of multi-dimensional hydraulic models where budget constraints would have otherwise prohibited their use. The accuracy and suitability of LiDAR data for supporting model development can vary widely depending on the resolution of channel and floodplain features, the data collection density, and the degree of vegetation canopy interference among other factors. More work is needed to develop guidelines for evaluating LiDAR accuracy and determining when and how best the data can be used to support numerical modeling activities. Here we present two recent case studies where LiDAR datasets were used to support floodplain and sediment transport modeling efforts. One LiDAR dataset was collected with a relatively low point density and used to study a small stream channel in coastal Marin County and a second dataset was collected with a higher point density and applied to a larger stream channel in western Sonoma County. Traditional topographic surveying was performed at both sites which provided a quantitative means of evaluating the LiDAR accuracy. We found that with the lower point density dataset, the accuracy of the LiDAR varied significantly between the active stream channel and floodplain whereas the accuracy across the channel/floodplain interface was more uniform with the higher density dataset. Accuracy also varied widely as a function of the density of the riparian vegetation canopy. We found that coupled 1- and 2-dimensional hydraulic

  12. ASME proceedings of the 32nd national heat transfer conference (HTD-Vol. 350). Volume 12: Fundamental experiment techniques in heat transfer; Thermal hydraulics of advanced nuclear reactors; Heat and mass transfer in supercritical liquid systems; Heat transfer in energy conversion; Heat transfer equipment; Heat transfer in gas turbine systems

    International Nuclear Information System (INIS)

    This volume contains a portion of the over 240 ASME papers which were presented at the conference. For over 40 years, the National Heat Transfer Conference has been the premiere forum for the presentation and dissemination of the latest advances in heat transfer. The work contained in these volumes range from studies of fundamental phenomena to applications in the latest heat transfer equipment. Topics covered in this volume are: Fundamental experiment techniques in heat transfer; thermal hydraulics of advanced nuclear reactors; heat and mass transfer in supercritical fluid systems; heat transfer in energy conversion; heat transfer equipment; and heat transfer in gas turbine systems. Separate abstracts were prepared for most papers in this volume

  13. Mineralogical, textural and physical-mechanical study of hydraulic lime mortars cured under different moisture conditions

    Directory of Open Access Journals (Sweden)

    Arizzi, A.

    2015-06-01

    Full Text Available This work focuses on the chemical-mineralogical, textural and physical-mechanical properties of hydraulic lime mortars made with siliceous and calcareous aggregate. Mortars were cured at 60% and 90% of relative humidity, so as to assess the variability of mortar petrophysical properties in the hardened state due to the moisture conditions. The final aim was to determine the most adequate moisture conditions to be maintained during application and hardening of hydraulic mortars intended for repair interventions. We found out that using a calcareous aggregate and curing mortar at 90% of relative humidity give place to better textural and mechanical properties. However, these characteristics mostly depend on the maximum size of the aggregate grains, which should be smaller than 6 mm, in order to avoid the occurrence of mechanical discontinuities in the mortar.En este trabajo se han estudiado las propiedades químico-mineralógicas, texturales y físico-mecánicas de morteros de cal hidráulica elaborados con áridos silíceo y calcítico. Estos morteros se han curado al 60% y 90% de humedad relativa, con el fin de evaluar las eventuales diferencias en las propiedades petrofísicas de los morteros una vez endurecidos y así establecer cuál de los dos ambientes es recomendable durante la aplicación y fraguado de morteros de cal hidráulica destinados a obras de restauración. Se ha encontrado que el uso de un árido de composición calcítica y el curado al 90% de humedad relativa dan lugar a morteros hidráulicos con mejores características texturales y propiedades mecánicas. De todas formas, estas características dependen principalmente del tamaño máximo del árido empleado, que debería ser inferior a 6 mm para evitar discontinuidades mecánicas en el mortero.

  14. Thermal-hydraulic studies on self actuated shutdown system for Japan Sodium-cooled Fast Reactor

    International Nuclear Information System (INIS)

    The self-actuated shutdown system (SASS), which is selected for Japan Sodium-cooled Fast Reactor (JSFR), is a passive reactor shutdown system utilizing a Curie point electromagnet (CPEM). With CPEM, an excessive fuel outlet temperature rise is sensed and the control rods are released into the core, and the reactor can be shutdown. Therefore it is important for feasibility of SASS to be established by assuring a quick response of CPEM to the coolant temperature rise. In this paper, a device named 'flow collector', which collects flows discharged from six fuel subassemblies surrounding CPEM backup control rods, has been proposed to ensure a shorter response time. Three-dimensional thermal-hydraulic analysis has been performed to evaluate the response time of CPEM with the flow collector, and it is confirmed that the coolant discharged from the fuel subassemblies flows into CPEM with high velocity and the response time of CPEM can be significantly shortened. Based on this analysis, the safety analysis has been carried out, confirming that the maximum temperatures of core and coolant are lower than those imposed by the safety criteria, and feasibility of SASS is assured. (author)

  15. Study of Effect of Seal Profile on Tribological Characteristics of Reciprocating Hydraulic Seals

    Directory of Open Access Journals (Sweden)

    S. Bhaumik

    2015-06-01

    Full Text Available Effect of seal profile on tribological characteristics such as leakage, friction, and wear in reciprocating hydraulic seals was predicted as a function of number of parameters such as rod velocity, sealed pressure and surface roughness. Experiments were conducted on a specially designed test rig at rod velocities ranging from 0.12-0.5 m/s, oil pressures from 1-20 MPa and rod average surface roughness value from 0.2-0.4 µm. Theoretical analysis was carried out using Greenwood Williamson (GW model for determining leakage, friction and Archard’s equation for evaluating wear in rectangular and U-cup seal profiles. Comparison of theoretically estimated data with experimental results for two seal profiles revealed good agreement. Unlike rectangular seal, back pumping of the fluid was observed in case of U-cup seal. It was also observed that, the performance of U-cup seal profile in terms of leakage, friction and wear was relatively better compared to rectangular seal profile under given set of test parameters.

  16. Management of a water distribution network by coupling GIS and hydraulic modeling: a case study of Chetouane in Algeria

    Science.gov (United States)

    Abdelbaki, Chérifa; Benchaib, Mohamed Mouâd; Benziada, Salim; Mahmoudi, Hacène; Goosen, Mattheus

    2016-04-01

    For more effective management of water distribution network in an arid region, Mapinfo GIS (8.0) software was coupled with a hydraulic model (EPANET 2.0) and applied to a case study region, Chetouane, situated in the north-west of Algeria. The area is characterized not only by water scarcity but also by poor water management practices. The results showed that a combination of GIS and modeling permits network operators to better analyze malfunctions with a resulting more rapid response as well as facilitating in an improved understanding of the work performed on the network. The grouping of GIS and modeling as an operating tool allows managers to diagnosis a network, to study solutions of problems and to predict future situations. The later can assist them in making informed decisions to ensure an acceptable performance level for optimal network operation.

  17. Study of IMT-advanced heterogeneous network

    Institute of Scientific and Technical Information of China (English)

    Qin Fei; Peng Ying; Sun Shaohui; Wang Yingmin

    2011-01-01

    Referring to research on the Heterogeneous Network (Het-Net) application scenario and technique characters in IMT-Advaneed (The 4th Generation Mobile Communications) cellular system, this paper provides further analysis on main technique aspects of Heterogeneous Network, discussion on interference issue due to multi-layer building by access points and their corresponding solutions from standardization and engineering implementation. The proposed solution can effectively solve the interference problem in IMT-advanced Het-Net, and also improves the networking performance dramaticaUy for future mobile communication systems.

  18. The Produce Technics Research about the Fabric Component on Advanced Downfall Coping Coal Hydraulic Pressure Support%放顶煤高端液压支架结构件制造工艺研究

    Institute of Scientific and Technical Information of China (English)

    魏鹏

    2014-01-01

    The text is according as advanced downfall coping coal hydraulic pressure support fabric component in recent years ,by controlling armor plate jointing ,fag end stress ,fag end distortion ,and its assort clearance ,we expatiated how to choose plate jointing ,logically choose fixing tolerance etc several pivotal advice ,lately we sumed up of the produce impact about advanced hydraulic pressure support .%对高强度低合金结构钢焊接、支架结构件残余应力及焊接残余变形的控制、高端液压支架结构件间配合间隙的合理选择板材下料、结构件拼装尺寸允差的合理选择等高端放顶煤液压支架制造过程中的几个关键问题进行了阐述,总结了高端放顶煤液压支架制造工艺。

  19. Results from five years of treatability studies using hydraulic binders to stabilize low-level mixed waste at the INEL

    International Nuclear Information System (INIS)

    This paper summarizes work involving bench-scale solidification of nonincinerable, land disposal restricted low-level mixed waste. Waste forms included liquids, sludges, and solids; treatment techniques included hydraulic systems (Portland cement with and without additives), proprietary commercial formulations, and sulphur polymer cement. Solidification was performed to immobilize hazardous heavy metals (including mercury, lead, chromium, and cadmium), and volatile and semivolatile organic compounds. Pretreatment options for mixed wastes are discussed, using a decision tree based on the form of mixed waste and the type of hazardous constituents. Hundreds of small concrete monoliths were formed for a variety of waste types. The experimental parameters used for the hydraulic concrete systems include the ratio of waste to dry binder (Portland cement, proprietary materials, etc.), the total percentage of water in concrete, and the amount of concrete additives. The only parameter that was used for the sulfur polymer-based monoliths is ratio of waste to binder. Optimum concrete formulations or open-quotes recipesclose quotes for a given type of waste were derived through this study, as based on results from the Toxicity Characteristic Leaching Procedure analyses and a free liquids test. Overall results indicate that high waste loadings in the concrete can be achieved while the monolithic mass maintains excellent resistance to leaching of heavy metals. In our study the waste loadings in the concrete generally fell within the range of 0.5 to 2.0 kg mixed waste per kg dry binder. Likewise, the most favorable amount of water in concrete, which is highly dependent upon the concrete constituents, was determined to be generally within the range of 300 to 330 g/kg (30-33% by weight). The results of this bench-scale study will find applicability at facilities where mixed or hazardous waste solidification is a planned or ongoing activity. 19 refs., 1 fig., 5 tabs

  20. Results from five years of treatability studies using hydraulic binders to stabilize low-level mixed waste at the INEL

    Energy Technology Data Exchange (ETDEWEB)

    Gering, K.L.; Schwendiman, G.L.

    1997-05-01

    This paper summarizes work involving bench-scale solidification of nonincinerable, land disposal restricted low-level mixed waste. Waste forms included liquids, sludges, and solids; treatment techniques included hydraulic systems (Portland cement with and without additives), proprietary commercial formulations, and sulphur polymer cement. Solidification was performed to immobilize hazardous heavy metals (including mercury, lead, chromium, and cadmium), and volatile and semivolatile organic compounds. Pretreatment options for mixed wastes are discussed, using a decision tree based on the form of mixed waste and the type of hazardous constituents. Hundreds of small concrete monoliths were formed for a variety of waste types. The experimental parameters used for the hydraulic concrete systems include the ratio of waste to dry binder (Portland cement, proprietary materials, etc.), the total percentage of water in concrete, and the amount of concrete additives. The only parameter that was used for the sulfur polymer-based monoliths is ratio of waste to binder. Optimum concrete formulations or {open_quotes}recipes{close_quotes} for a given type of waste were derived through this study, as based on results from the Toxicity Characteristic Leaching Procedure analyses and a free liquids test. Overall results indicate that high waste loadings in the concrete can be achieved while the monolithic mass maintains excellent resistance to leaching of heavy metals. In our study the waste loadings in the concrete generally fell within the range of 0.5 to 2.0 kg mixed waste per kg dry binder. Likewise, the most favorable amount of water in concrete, which is highly dependent upon the concrete constituents, was determined to be generally within the range of 300 to 330 g/kg (30-33% by weight). The results of this bench-scale study will find applicability at facilities where mixed or hazardous waste solidification is a planned or ongoing activity. 19 refs., 1 fig., 5 tabs.

  1. Theoretical and numerical study of hydraulic characteristics of orifice energy dissipator

    Directory of Open Access Journals (Sweden)

    NingHE

    2010-06-01

    Full Text Available Different factors affecting the efficiency of the orifice energy dissipator were investigated based on a series of theoretical analyses and numerical simulations. The main factors investigated by dimension analysis were identified, including the Reynolds number (Re, the ratio of the orifice diameter to the inner diameter of the pipe ( , and the ratio of distances between orifices to the inner diameter of the pipe ( . Then, numerical simulations were conducted with a two-equation turbulence model. The calculation results show the following: Hydraulic characteristics change dramatically as flow passes through the orifice, with abruptly increasing velocity and turbulent energy, and decreasing pressure. The turbulent energy appears to be low in the middle and high near the pipe wall. For the energy dissipation setup with only one orifice, when Re is smaller than 105, the orifice energy dissipation coefficient K increases rapidly with the increase of Re. When Re is larger than 105, K gradually stabilizes. As increases, K and the length of the recirculation region L1 show similar variation patterns, which inversely vary with . The function curves can be approximated as straight lines. For the energy dissipation model with two orifices, because of different incoming flows at different orifices, the energy dissipation coefficient of the second orifice (K2 is smaller than that of the first. If is less than 5, the K value of the model, depending on the variation of K2, increases with the spacing between two orifices L , and an orifice cannot fulfill its energy dissipation function. If is greater than 5, K2 tends to be steady; thus, the K value of the model gradually stabilizes. Then, the flow fully develops, and L has almost no impact on the value of K.

  2. Engineered barrier experiments and analytical studies on coupled thermal - hydraulic - chemical processes in bentonite buffer material

    International Nuclear Information System (INIS)

    It is anticipated that thermal - hydraulic - mechanical - chemical (THMC) processes will be coupled in the bentonite buffer material of a high-level radioactive waste repository. The main contributors to these processes are heat arising from the radioactive decay of the vitrified waste, infiltration of groundwater from the host rock and/or leachate from the cementitious component of the repository, and the consequent increase in swelling pressure and chemical reactions. In order to evaluate these coupled processes in the bentonite buffer material, it is necessary to take steps towards the development of a credible and robust THMC model. The current paper describes the measured data of an engineering-scale coupled THC process experiment and the calculated results of a THC model undergoing development. The coupled experiment used an electric heater, bentonite blocks and a mortar block, subjected to infiltrating water to simulate a high-alkaline porewater derived from the concrete tunnel support seeping into the bentonite buffer material under a thermal gradient provided by the vitrified waste. Temperature and water content of the bentonite buffer material were measured by several sensors continuously for several months. After this time, the buffer material was sampled. The results of mineral analysis of the samples suggested that the precipitate of amorphous hydrate with silica was found in the buffer material in contact with the mortar. The developing THC model simulated C-S-H gel precipitation as a secondary mineral in the exact same locality because of the solution being saturated with respect to portlandite and chalcedony, thereby providing some confidence in the chemical feature of the developing THC model. Some important issues in the future development of the model were also identified, including the concentration of porewater being influenced by vapor movement in the bentonite buffer material due to heating from the vitrified waste and geochemical reactions

  3. Skills Required for Nursing Career Advancement: A Qualitative Study

    Science.gov (United States)

    Sheikhi, Mohammad Reza; Fallahi-Khoshnab, Masoud; Mohammadi, Farahnaz; Oskouie, Fatemeh

    2016-01-01

    Background Nurses require certain skills for progression in their field. Identifying these skills can provide the context for nursing career advancement. Objectives This study aimed to identify the skills needed for nurses’ career advancement. Materials and Methods A qualitative approach using content analysis was adopted to study a purposive sample of eighteen nurses working in teaching hospitals affiliated with the Qazvin, Shahid Beheshti, and Iran Universities of Medical Sciences. The data were collected through semi-structured interviews, and analyzed using conventional content analysis. Results The three themes extracted from the data included interpersonal capabilities, competency for career success, and personal capacities. The results showed that acquiring a variety of skills is essential for career advancement. Conclusions The findings showed that personal, interpersonal, and functional skills can facilitate nurses’ career advancement. The effects of these skills on career advancement depend on a variety of conditions that require further studies. PMID:27556054

  4. Experimental simulation study on hydraulic behavior of the main heat exchanger of Daqing 200 MW nuclear heating reactor

    International Nuclear Information System (INIS)

    The hydraulic behavior of the main heat exchanger of Daqing 200 MW nuclear heating reactor is studied through a 1:2.33 test model. The design and other feature of the test model is described. The experimental results show that the flow resistance coefficient of the heat exchanger becomes self-simulation when Reynolds number is greater than 5000. The value of flow resistance coefficient at self-simulation condition and the distribution of pressure drop in the heat exchanger are given through experiment. The option design to reduce flow resistance is proposed. The designed and experimental value for the flow resistance coefficient are in good agreement. The variation of system parameters during flow excursion was described. The experimental results are of great significant for the final design of the main heat exchanger of Daqing 200 MW nuclear heating reactor. (2 refs., 5 figs., 1 tab.)

  5. CONTRIBUTION TO THE EXPERIMENTAL STUDY OF THE HYDRAULIC JUMP EVOLVING IN AN U-SHAPED CHANNEL, WITH ROUGH BED

    Directory of Open Access Journals (Sweden)

    A. Ghomri

    2010-12-01

    Full Text Available This study aims to investigate the threshold-controlled hydraulic jump, moving in channel profile 'U' fully rough for a single roughness value  = 7,14 mm. Functional relations in dimensionless terms, linking the different characteristics of the jump, showing the effect of bottom friction channel, are obtained as: y2= (-14,19y1 + 6, 42 Q*; y2= 1,13y10,65 exp [0,95y10,61.s/h1] . The method is as follows: we vary the flow volume by manipulating the valve and their measurements are read directly on the meter display éctronique. Supply channel is by means of a pump flow up 40 l / s. The flume was designed in the laboratory 'LARHYSS, University of Biskra.

  6. Thermal-hydraulics and neutronics studies on the FP7 CP-ESFR oxide and carbide cores

    International Nuclear Information System (INIS)

    In the framework of the the Collaborative Project on European Sodium Fast Reactor (CP-ESFR) two core designs that are currently being proposed for the 3600 MWth sodium-cooled reactor concept: one is based on oxide fuel and the other on carbide fuel. Using the European Safety Assessment Platform (ESAP), JRC-IE has conducted static calculation on neutronics (incl. reactivity coefficients) and thermal-hydraulic characteristics for both oxide and carbide reference cores. The quantities evaluated include: keff, coolant heat-up, void, and Doppler reactivity coefficients, axial and radial expansion reactivity coefficients, pin-by-pin calculated power profiles, average and peak channel temperatures. This paper presents the ESAP models applied in the study together with the relevant results for the oxide and carbide core. (author)

  7. Optimal Choice of Soil Hydraulic Parameters for Simulating the Unsaturated Flow: A Case Study on the Island of Miyakojima, Japan

    Directory of Open Access Journals (Sweden)

    Ken Okamoto

    2015-10-01

    Full Text Available We examined the influence of input soil hydraulic parameters on HYDRUS-1D simulations of evapotranspiration and volumetric water contents (VWCs in the unsaturated zone of a sugarcane field on the island of Miyakojima, Japan. We first optimized the parameters for root water uptake and examined the influence of soil hydraulic parameters (water retention curve and hydraulic conductivity on simulations of evapotranspiration. We then compared VWCs simulated using measured soil hydraulic parameters with those using pedotransfer estimates obtained with the ROSETTA software package. Our results confirm that it is important to always use soil hydraulic parameters based on measured data, if available, when simulating evapotranspiration and unsaturated water flow processes, rather than pedotransfer functions.

  8. Advances in radiobiological studies using a microbeam

    International Nuclear Information System (INIS)

    Recent developments in microbeam technology have made drastic improvements in particle delivery, focusing, image processing and precision to allow for rapid advances in our knowledge in radiation biology. The unequivocal demonstration that targeted cytoplasmic irradiation results in mutations in the nuclei of hit cells and the presence of non-targeted effects, all made possible using a charged particle microbeam, results in a paradigm shift in our basic understanding of the target theory and other radiation-induced low dose effects. The demonstration of a bystander effect in 3D human tissue and whole organisms have shown the potential relevance of the non-targeted response in human health. The demonstration of delayed mutations in the progeny of bystander cells suggest that genomic instability induced following ionizing radiation exposure is not dependent on direct damage to cell nucleus. The identification of specific signaling pathways provides mechanistic insight on the nature of the bystander process. (author)

  9. Hydrodynamic parameters diversification in the watercourse with the rapid hydraulic structures (case study of the Porębianka River, Polish Carpathians

    Directory of Open Access Journals (Sweden)

    Karol PLESIŃSKI

    2015-01-01

    Full Text Available In modern river training practices and philosophy one can notice coming more into use ecological friendly hydraulic structures. Those, which are especially needed for river training works, as far as expectation of Water Framework Directive is concerned, are rapid hydraulic structures (RHS. What is important, RHS in general do not stop fish and invertebrates against migrating upstream, provide natural and esthetical effects within the river channel, still working as hydraulic engineering structures. The main aim of the research was to describe changes of values of those parameters upstream and downstream of the RHS’s and to find out their influence on hydrodynamics of the stream. The study was undertaken on the Porębianka river in the Gorce Mountains, Polish Carpathians. Along this paper we described and measured some hydraulic parameters within the reach of chosen rapid hydraulic structures, which we found in the field. Observed hydrodynamic parameters within the reach of the RHS’s depend on the location of measuring point and the influence of individual part of the structure. At the same time maximum velocity does not always create the bigger shear force, because it is also depend on the velocity distribution along the hydrological profile

  10. Theoretical and numerical study of hydraulic characteristics of orifice energy dissipator

    Institute of Scientific and Technical Information of China (English)

    Ning HE; Zhen-xing ZHAO

    2010-01-01

    Different factors affecting the efficiency of the orifice energy dissipator were investigated based on a series of theoretical analyses and numerical simulations.The main factors investigated by dimension analysis were identified,including the Reynolds number(Re),the ratio of the orifice diameter to the inner diameter of the pipe(d/D),and the ratio of distances between orifices to the inner diameter of the pipe(L/D).Then,numerical simulations were conducted with a k-ε two-equation turbulence model.The calculation results show the following:Hydraulic characteristics change dramatically as flow passes through the orifice,with abruptly increasing velocity and turbulent energy,and decreasing pressure.The turbulent energy appears to be low in the middle and high near the pipe wall.For the energy dissipation setup with only one orifice,when Re is smaller than 105,the orifice energy dissipation coefficient K increases rapidly with the increase of Re.When Re is larger than 105,K gradually stabilizes.As d/D increases,K and the length of the recirculation region L1 show similar variation patterns,which inversely vary with d/D.The function curves can be approximated as straight lines.For the energy dissipation model with two orifices,because of different incoming flows at different orifices,the energy dissipation coefficient of the second orifice(K2)is smaller than that of the first.If L/D is less than 5,the K value of the L/D model,depending on the variation of K2,increases with the spacing between two orifices L,and an orifice cannot fulfill its energy dissipation function.If L/D is greater than 5,K2 tends to be steady; thus,the K value of the L/D model gradually stabilizes.Then,the flow fully develops,and L has almost no impact on the value of K.

  11. Experimental study on the bank erosion and interaction with near-bank bed evolution due to fluvial hydraulic force

    Institute of Scientific and Technical Information of China (English)

    Ming-hui YU; Hong-yan WEI; Song-bai WU

    2015-01-01

    Bank erosion is a typical process of lateral channel migration, which is accompanied by vertical bed evolution. As a main sediment source, the failed bank soil may directly cause the increase of sediment concentration and considerable channel evolution in a short time. The paper presents an experimental study on non-cohesive and cohesive homogenous bank failure processes, influence of the failed bank soil on bank re-collapse, as well as the interaction between bank failure and near-bank bed evolution due to fluvial hydraulic force. A series of experiments were carried out in a 180° bend rectangular flume. The results reveal the iteration cycle between bank erosion and bed deformation: undercutting of the riverbank, slip failure of the submerged zone of the bank, as well as cantilever failure of the overhang, failed bank soil staying at bank toe temporarily or hydraulic transportation, exchange between the failed bank soil and bed material, bed material load being re-transported either as bed load or as suspended load, and bed deformation. Same as bank failure, the mixing of failed bank soil and bed material is more severe near the curved flow apex. Moreover, non-cohesive bank failure tends to occur near the water surface while cohesive bank failure near the bank toe. For non-cohesive dense (sandy) soil, the bank erosion amount and residual amount of failed bank soil on the bed increase with the near-bank velocity or bed erodibility. But for cohesive soil, only bank erosion amount follows the above rule. The results are expected to provide theoretical basis for river management and flood prevention.

  12. ECO-HYDRAULICS TECHNIQUES FOR CONTROLLING EUTROPHICATION OF SMALL SCENERY LAKES-A CASE STUDY OF LUDAO LAKE IN SHANGHAI

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Ludao Lake with an area of 0.86 km2 and 50% water surface ratio, was taken as an example to study the eco-hydraulics techniques for preventing lake eutrophication. Besides external water inflow and outflow, the term related to internal local flow circulation was added in the continuity equation of two-dimensional horizontal hydrodynamic model, and further the hydrodynamic model was calibrated by the scenario of no water exchange. The velocity of 0.2 m/s was suggested to be the critical velocity of controlling algal bloom. To achieve the critical velocity in the whole lake, three factors were analyzed, which are wind, artificial external inflow augmentation and internal local flow disturbance by pump circulation. It is found that the role of wind can be disregarded. For the eco-hydraulics technique of external lake water inflow augmentation, the water flowing route should be firstly optimized, further, the lake inflow has a critical value under specified water level due to the narrow inlets, so the whole lake is difficult to reach the critical velocity to prevent algal bloom, and a combination of external inflow augmentation and internal local flowing disturbance should be considered. Simulation results show that the combination of external water inflow augmentation and internal local flow disturbance requires less eco-flow to achieve the global critical velocity than the sole internal local flow disturbance, for the Ludao Lake, the former requires total eco-flow of 25 m3/s, which reduces by 50% than the latter requiring total eco-flow of 52 m3/s.

  13. Study of the hydraulic regime of the St. Lawrence River between Montreal and the city of Quibec

    Energy Technology Data Exchange (ETDEWEB)

    Robert, S.; Rassam, J.-C.; Lariviere, R. (Hydro-Quebec, Montreal, PQ (Canada)); Piotte, D.; Boivin, R.; Hausser, R. (Lasalle Hydraulic Lab., PQ (Canada))

    1992-01-01

    Results are presented from a major hydraulic regime study of the St. Lawrence River carried out over a distance of 285 km between the Beauharnois and Carillon generating stations and Quebec City. The results focus mainly on the parameters that explain water level variations where the river is used most intensively for commercial shipping. Outflows from generating stations give rise to water level variations that could theoretically have an impact on the river. The upstream network, basically consisting of two lakes, was modelled using Hydro-Quebec's ARCHIP model. The downstream network simulations were performed in the transient flow regime with the Environment Canada hydrodynamic model 1D. Five main tributaries were incorporated into this model, and the downstream network was calibrated by adjusting the model's physical parameters to data observed during three 3-week periods. Using a series of numerical simulations, the factors that affect water levels were isolated and their particular contributions were estimated. In particular, the effects of the flows, local inflows, flow variations, and tide on the water levels along the St. Lawrence maritime channel were analyzed. It was shown that, although the water levels depend strongly on average discharge rates from Beauharnois and Carillon generating stations, they are less sensitive to discharge variations resulting from daily generating station operations. The effect of the tide is an important factor in the hydraulic behavior of the St. Lawrence River, even as high as Montreal, where the tide can explain water level variations of 30 cm at times during the year when the flow rate is low. 4 refs., 9 figs., 3 tabs.

  14. Application feasibility study of evaluation technology for long-term rock behavior. 1. Coupled hydraulic and mechanical analysis to evaluate rock behavior of shaft in fault

    International Nuclear Information System (INIS)

    The main shaft of Mizunami URL is located in fault, and the hydrological anisotropy due to the geology is observed. Lining deformation may cause by increase of lining stress with degradation of drain material or aquifer of changes in the future. In this study, by implementing coupled hydraulic and mechanical analyses, validity of methods of analysis is considered as compared to measuring for hydrological anisotropy. According to the result of these analyses, water pressure dependency was not shown, but the main shaft behavior was simulated taking account of hydrological anisotropy. Also validity of methods of coupled hydraulic and mechanical analyses as deterioration prediction was confirmed. (author)

  15. Evolution of developments and applications of advanced thermal-hydraulics and neutronic codes. Conclusions from Annapolis Workshop and Ankara Seminar, Objectives of the Present Workshop

    International Nuclear Information System (INIS)

    In the nuclear reactor safety area, during the last 30-40 years, thermal-hydraulics has been one of the key disciplines for simulation and analysis of transient and accident scenarios and also for the definition of preventive and mitigative measures in relation to these scenarios. A workshop was organised by OECD/NEA-CSNI at Annapolis (1996) where codes, physical models, numeric and new computer architecture were examined. In parallel a Specialist meeting on instrumentation in two phase flows was held in Santa Barbara beginning of 1997 in order to investigate new techniques for getting measurements of new physical parameters necessary for assessing the new physical models. Among the different applications of thermal-hydraulic codes, the use of Best Estimate methods in safety evaluation is certainly one of the major challenges for which the safety and economic issues are quite important. For these reasons OECD/NEA-CSNI organised a seminar in Ankara in 1998 entirely devoted to the use of Best Estimate methods in thermal-hydraulics analysis. This seminar allowed to get a better view of where we were in such applications and which were the remaining problems and issues. The present workshop held in Barcelona beginning of year 2000 will be a good opportunity for providing an updated review of the gained progresses and for analysing if the objectives and programs are still progressing in the right direction. In order to do such exercise, we will first recall the questions which were raised in Annapolis and the main conclusions which were drawn from these questions. The conclusions of Ankara Meeting will be reviewed in a second step. Finally we will list the objectives of this workshop in Barcelona which is held in the continuity of Annapolis Workshop and Ankara Seminar. (authors)

  16. Study on fracture behavior within rock made by hydraulic fracturing; Suiatsu hasai ni yoru ganbannai kiretsu no kyodo ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-07

    The paper studied the thickness of crack made in deep underground and the distribution of hydraulic pressure of the fluid flowing in the crack. The study having been made were described on hydraulic fracturing, water flow in the crack, and dynamic behavior of cracks. The result was showed of the estimation of width of the crack made in the laboratory experiment and the distribution of hydraulic pressure in the crack. To confirm whether or not the distribution of crack thickness can be estimated from surface displacement even if making the specimen larger by the above-mentioned method, an experiment as small-scale id-situ experiment was conducted with the wall face of mine roadway as the observation area for the displacement. From the surface displacement, validity was discussed of a method to estimate the hydraulic pressure in the crack and the distribution of aperture width. An estimation was attempted of the distribution of aperture width of the crack made in the hydraulic fracturing test conducted in 1992 at the site of the Hijiori hot dry rock power generation. The paper summarized the result of estimating the distribution of hydraulic pressure in the crack and the distribution of crack thickness in experiments different in scale and the knowledge/information obtained in the estimation, based on the pressure distribution determined from the cubic law including the fluid flow friction proposed by Lomize and on the relation between the earth pressure and the crack width of the Bed-of-Nails model. 81 refs., 90 figs., 6 tabs.

  17. Study of advanced LWR cores for effective use of plutonium and MOX physics experiments

    International Nuclear Information System (INIS)

    Advanced technologies of full MOX cores have been studied to obtain higher Pu consumption based on the advanced light water reactors (APWRs and ABWRs). For this aim, basic core designs of high moderation lattice (H/HM ∼5) have been studied with reduced fuel diameters in fuel assemblies for APWRs and those of high moderation lattice (H/HM ∼6) with addition of extra water rods in fuel assemblies for ABWRs. The analysis of equilibrium cores shows that nuclear and thermal hydraulic parameters satisfy the design criteria and the Pu consumption rate increases about 20 %. An experimental program has been carried out to obtain the core parameters of high moderation MOX cores in the EOLE critical facility at the Cadarache Centre as a joint study of NUPEC, CEA and CEA's industrial partners. The experiments include a uranium homogeneous core, two MOX homogeneous cores of different moderation and a PWR assembly mock up core of MOX fuel with high moderation. The program was started from 1996 and will be completed in 2000. (author)

  18. Advanced Burner Reactor Preliminary NEPA Data Study

    International Nuclear Information System (INIS)

    The Global Nuclear Energy Partnership (GNEP) is a new nuclear fuel cycle paradigm with the goals of expanding the use of nuclear power both domestically and internationally, addressing nuclear waste management concerns, and promoting nonproliferation. A key aspect of this program is fast reactor transmutation, in which transuranics recovered from light water reactor spent fuel are to be recycled to create fast reactor transmutation fuels. The benefits of these fuels are to be demonstrated in an Advanced Burner Reactor (ABR), which will provide a representative environment for recycle fuel testing, safety testing, and modern fast reactor design and safeguard features. Because the GNEP programs will require facilities which may have an impact upon the environment within the meaning of the National Environmental Policy Act of 1969 (NEPA), preparation of a Programmatic Environmental Impact Statement (PEIS) for GNEP is being undertaken by Tetra Tech, Inc. The PEIS will include a section on the ABR. In support of the PEIS, the Nuclear Engineering Division of Argonne National Laboratory has been asked to provide a description of the ABR alternative, including graphics, plus estimates of construction and operations data for an ABR plant. The compilation of this information is presented in the remainder of this report. Currently, DOE has started the process of engaging industry on the design of an Advanced Burner Reactor. Therefore, there is no specific, current, vendor-produced ABR design that could be used for this PEIS datacall package. In addition, candidate sites for the ABR vary widely as to available water, geography, etc. Therefore, ANL has based its estimates for construction and operations data largely on generalization of available information from existing plants and from the environmental report assembled for the Clinch River Breeder Reactor Plant (CRBRP) design [CRBRP, 1977]. The CRBRP environmental report was chosen as a resource because it thoroughly

  19. Advanced Burner Reactor Preliminary NEPA Data Study.

    Energy Technology Data Exchange (ETDEWEB)

    Briggs, L. L.; Cahalan, J. E.; Deitrich, L. W.; Fanning, T. H.; Grandy, C.; Kellogg, R.; Kim, T. K.; Yang, W. S.; Nuclear Engineering Division

    2007-10-15

    The Global Nuclear Energy Partnership (GNEP) is a new nuclear fuel cycle paradigm with the goals of expanding the use of nuclear power both domestically and internationally, addressing nuclear waste management concerns, and promoting nonproliferation. A key aspect of this program is fast reactor transmutation, in which transuranics recovered from light water reactor spent fuel are to be recycled to create fast reactor transmutation fuels. The benefits of these fuels are to be demonstrated in an Advanced Burner Reactor (ABR), which will provide a representative environment for recycle fuel testing, safety testing, and modern fast reactor design and safeguard features. Because the GNEP programs will require facilities which may have an impact upon the environment within the meaning of the National Environmental Policy Act of 1969 (NEPA), preparation of a Programmatic Environmental Impact Statement (PEIS) for GNEP is being undertaken by Tetra Tech, Inc. The PEIS will include a section on the ABR. In support of the PEIS, the Nuclear Engineering Division of Argonne National Laboratory has been asked to provide a description of the ABR alternative, including graphics, plus estimates of construction and operations data for an ABR plant. The compilation of this information is presented in the remainder of this report. Currently, DOE has started the process of engaging industry on the design of an Advanced Burner Reactor. Therefore, there is no specific, current, vendor-produced ABR design that could be used for this PEIS datacall package. In addition, candidate sites for the ABR vary widely as to available water, geography, etc. Therefore, ANL has based its estimates for construction and operations data largely on generalization of available information from existing plants and from the environmental report assembled for the Clinch River Breeder Reactor Plant (CRBRP) design [CRBRP, 1977]. The CRBRP environmental report was chosen as a resource because it thoroughly

  20. Magnetic suspension and balance system advanced study, 1989 design

    Science.gov (United States)

    Boom, Roger W.; Eyssa, Y. M.; Abdelsalam, Moustafa K.; Mcintosh, Glen E.

    1991-01-01

    The objectives are to experimentally confirm several advanced design concepts on the Magnetic Suspension and Balance Systems (MSBS). The advanced design concepts were identified as potential improvements by Madison Magnetics, Inc. (MMI) during 1984 and 1985 studies of an MSBS utilizing 14 external superconductive coils and a superconductive solenoid in an airplane test model suspended in a wind tunnel. This study confirmed several advanced design concepts on magnetic suspension and balance systems. The 1989 MSBS redesign is based on the results of these experiments. Savings of up to 30 percent in supporting magnet ampere meters and 50 percent in energy stored over the 1985 design were achieved.

  1. Cosmos, an international center for advanced studies

    Science.gov (United States)

    Ryzhov, Iurii; Alifanov, Oleg; Sadin, Stanley; Coleman, Paul

    1990-01-01

    The concept of Cosmos, a Soviet operating center for aerospace activities, is presented. The main Cosmos participants are the Institute for Aerospace Education, the Institute for Research and Commercial Development, and the Department of Space Policy and Socio-Economic Studies. Cosmos sponsors a number of educational programs, basic research, and studies of the social impact of space-related technologies.

  2. Advances in froth treatment pilot plant studies

    Energy Technology Data Exchange (ETDEWEB)

    Shelfantook, W.E. [Syncrude Canada Ltd., Edmonton, AB (Canada)

    1997-11-01

    Bench-scale studies have been performed to find ways to produce diluted bitumen containing less than 1 per cent water. The studies showed that using diluents of high paraffin concentration and elevated solvent ratios could yield very dry diluted bitumen. The laboratory studies led to a series of pilot studies in froth treatment conducted at the facilities of the Canadian Oilsand Network for Research and Development (CONRAD). The pilot studies focused on defining the operating envelope for the Paraffin Froth Treatment Process and establishing the process` response to solvent ratio and temperature. Many different solvent materials were tested to determine their impact on process performance. The work has been part of a development plan for Oilsand leases north of Fort McMurray.

  3. Experimental Study on the Hydraulic Fractures' Morphology of Coal Bed%煤岩水力压裂裂缝形态实验研究

    Institute of Scientific and Technical Information of China (English)

    程远方; 徐太双; 吴百烈; 李娜; 袁征; 孙元伟; 王欣

    2013-01-01

    The correct judgment of the hydraulic fractures' morphology is very important part for fracturing operation design and productivity prediction. This paper studied the true tri-axial hydraulic fracture experiment of coal and obtained the judgment criterions for the conversion conditions between horizontal, vertical and complicated fracture. The result shows that the hydraulic fractures morphology will be changed between vertical and horizontal fracture when the stress difference (the minimum horizontal stress minus vertical stress) span from 4MPa to 6MPa. High confining pressures will make the hydraulic fractures morphology complicated when the stress difference is stable. The nature fractures and cleats have different effects on the initiation and extending process of hydraulic fracture. The stress states of coal bed decide the hydraulic fracture strike. When the stress difference coefficient,i, e. Kv,belongs to 0. 6 to 0. 7,the nature fractures and cleats have significant influence on the hydraulic fractures morphology. From the Kv value, we can know that it need harsh stress condition to make the hydraulic fractures horizontal at the stage of initiation without near wellbore nature fracture.%水力裂缝形态的正确判断是压裂施工设计和产能预测的重要部分,针对煤岩进行真三轴水力压裂,研究水平裂缝、垂直裂缝和复杂裂缝之间的转换条件,得出判断依据.实验证实:应力差(最小水平地应力减去垂向应力)为4~6MPa时,水力裂缝形态在垂直裂缝和水平裂缝间转变;在等应力差状态下,高围压状态会使水力裂缝形态趋于复杂;天然裂缝和割理对水力裂缝起裂与延伸过程产生不同影响;煤岩应力状态主导水力裂缝走向,当应力差异系数Kv在0.6~0.7之间时,煤岩内部天然裂缝和割理对水力裂缝形态有显著影响;并且在不考虑井眼附近天然裂缝时,需要苛刻的应力条件使水力裂缝的起裂阶段表现为水平裂缝.

  4. Advances in phylogenetic studies of Nematoda

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Nematoda is a metazoan group with extremely high diversity only next to Insecta. Caenorhabditis elegans is now a favorable experimental model animal in modern developmental biology, genetics and genomics studies. However, the phylogeny of Nematoda and the phylogenetic position of the phylum within animal kingdom have long been in debate. Recent molecular phylogenetic studies gave great challenges to the traditional nematode classification. The new phylogenies not only placed the Nematoda in the Ecdysozoan and divided the phylum into five clades, but also provided new insights into animal molecular identification and phylogenetic biodiversity studies. The present paper reviews major progress and remaining problems in the current molecular phylogenetic studies of Nematoda, and prospects the developmental tendencies of this field.

  5. Experimental Study of Crack Initiation and Extension Induced by Hydraulic Fracturing in a Tree-Type Borehole Array

    OpenAIRE

    Yiyu Lu; Shaojie Zuo; Zhaolong Ge; Songqiang Xiao; Yugang Cheng

    2016-01-01

    High-pressure hydraulic fracturing technology in coal and coal bed methane mines can lead to roof and floor damage, and fracture initiation disorder that leads to a “blank area”, and other issues. A new method of hydraulic fracturing is proposed to increase the homogeneous permeability of coal in underground coalmines. Numerical and other simulation tests for different forms of a tree-type, branched borehole model are presented. The results show that the branched array causes cracks to initia...

  6. METHODS ADVANCEMENT FOR MILK ANALYSIS: THE MAMA STUDY

    Science.gov (United States)

    The Methods Advancement for Milk Analysis (MAMA) study was designed by US EPA and CDC investigators to provide data to support the technological and study design needs of the proposed National Children=s Study (NCS). The NCS is a multi-Agency-sponsored study, authorized under the...

  7. Advances in clinical study of curcumin.

    Science.gov (United States)

    Yang, Chunfen; Su, Xun; Liu, Anchang; Zhang, Lin; Yu, Aihua; Xi, Yanwei; Zhai, Guangxi

    2013-01-01

    Curcumin has been estimated as a potential agent for many diseases and attracted great attention owing to its various pharmacological activities, including anti-cancer, and anti-inflammatory. Now curcumin is being applied to a number of patients with breast cancer, rheumatoid arthritis, Alzheimer's disease, colorectal cancer, psoriatic, etc. Several clinical trials have stated that curcumin is safe enough and effective. The objective of this article was to summarize the clinical studies of curcumin, and give a reference for future studies. PMID:23116307

  8. [Advances in studies on flavonoids of licorice].

    Science.gov (United States)

    Xing, Guo-xiu; Li, Nan; Wang, Tong; Yao, Mei-yan

    2003-07-01

    The progress in the research of the active ingredients of licorice flavonoid and the pharmacological activities was reviewed. Licorice flavonoid constituents mainly included flavones, flavonals, isoflavones, chalcones, bihydroflavones and bihydrochalcones. Pharmacological investigation concluded that they had antioxidant, antibacterial, antitumer and inhibiting HIV activities. It is important to study further the flavonoid constituents and pharmacological activities. PMID:15139098

  9. Uncertainty in training image-based inversion of hydraulic head data constrained to ERT data: Workflow and case study

    Science.gov (United States)

    Hermans, Thomas; Nguyen, Frédéric; Caers, Jef

    2015-07-01

    In inverse problems, investigating uncertainty in the posterior distribution of model parameters is as important as matching data. In recent years, most efforts have focused on techniques to sample the posterior distribution with reasonable computational costs. Within a Bayesian context, this posterior depends on the prior distribution. However, most of the studies ignore modeling the prior with realistic geological uncertainty. In this paper, we propose a workflow inspired by a Popper-Bayes philosophy that data should first be used to falsify models, then only be considered for matching. We propose a workflow consisting of three steps: (1) in defining the prior, we interpret multiple alternative geological scenarios from literature (architecture of facies) and site-specific data (proportions of facies). Prior spatial uncertainty is modeled using multiple-point geostatistics, where each scenario is defined using a training image. (2) We validate these prior geological scenarios by simulating electrical resistivity tomography (ERT) data on realizations of each scenario and comparing them to field ERT in a lower dimensional space. In this second step, the idea is to probabilistically falsify scenarios with ERT, meaning that scenarios which are incompatible receive an updated probability of zero while compatible scenarios receive a nonzero updated belief. (3) We constrain the hydrogeological model with hydraulic head and ERT using a stochastic search method. The workflow is applied to a synthetic and a field case studies in an alluvial aquifer. This study highlights the importance of considering and estimating prior uncertainty (without data) through a process of probabilistic falsification.

  10. Advanced microwave radiometer antenna system study

    Science.gov (United States)

    Kummer, W. H.; Villeneuve, A. T.; Seaton, A. F.

    1976-01-01

    The practicability of a multi-frequency antenna for spaceborne microwave radiometers was considered in detail. The program consisted of a comparative study of various antenna systems, both mechanically and electronically scanned, in relation to specified design goals and desired system performance. The study involved several distinct tasks: definition of candidate antennas that are lightweight and that, at the specified frequencies of 5, 10, 18, 22, and 36 GHz, can provide conical scanning, dual linear polarization, and simultaneous multiple frequency operation; examination of various feed systems and phase-shifting techniques; detailed analysis of several key performance parameters such as beam efficiency, sidelobe level, and antenna beam footprint size; and conception of an antenna/feed system that could meet the design goals. Candidate antennas examined include phased arrays, lenses, and optical reflector systems. Mechanical, electrical, and performance characteristics of the various systems were tabulated for ease of comparison.

  11. Advanced NSTS propulsion system verification study

    Science.gov (United States)

    Wood, Charles

    1989-01-01

    The merits of propulsion system development testing are discussed. The existing data base of technical reports and specialists is utilized in this investigation. The study encompassed a review of all available test reports of propulsion system development testing for the Saturn stages, the Titan stages, and the Space Shuttle main propulsion system. The knowledge on propulsion system development and system testing available from specialists and managers was also 'tapped' for inclusion.

  12. Evaluation of advanced hydraulic turbomachinery for underground pumped hydroelectric storage. Part 1. Single-stage regulated pump turbines for operating heads of 500 to 1000 m

    Energy Technology Data Exchange (ETDEWEB)

    Frigo, A.A.; Blomquist, C.A.; Degnan, J.R.

    1979-10-01

    High-head, large-capacity turbomachinery is needed for the concept of underground pumped hydroelectric storage to be technically and economically attractive. Single-stage, reversible, Francis-type pump turbines with adjustable wicket gates appear to offer the most economically attractive option for heads between about 500 and 1000 m. The feasibility of developing these types of machines for capacities up to 500 MW and operating heads up to 1000 m has been evaluated. Preliminary designs have been generated for six single-stage pump turbines. The designs are for capacities of 350 and 500 MW and for operating heads of 500, 750, and 1000 m. The report contains drawings of the machines along with material specifications and hydraulic performance data. Mechanical, hydraulic, and economic analyses indicate that these machines will behave according to the criteria used to design them and that they can be built at a reasonable cost. The stress and deflection responses of the 500-MW, 100-m-head pump turbine, determined by detailed finite element analysis techniques, give solid evidence of the integrity of the conceptual designs of the six units and indicate no unsolvable problems. Results of a life expectancy analysis of the wicket gates indicate that a near infinite life can be expected for these components when they are subjected to normal design loads. Efficiencies of 90.7 and 91.4% in the generating and pumping modes, respectively, can be expected for the 500-MW, 1000-m-head unit. Performances of the other five machines are comparable. The specific costs of the pump turbines in mid-1978 US dollars per kW vary from 19.2 to 11.8 over a head range of from 500 to 1000 m for the 500-MW machines and from 20.0 to 12.3 for the 350-MW machines.

  13. Advances from neuroimaging studies in eating disorders

    Science.gov (United States)

    Frank, Guido K.W.

    2016-01-01

    Over the past decade brain imaging has helped better define eating disorder related brain circuitry. Brain research on gray and white matter volumes had been inconsistent, possibly due to the effects of acute starvation, exercise, medication and comorbidity, but newer studies controlled for such effects. Those studies suggest larger left medial orbitofrontal gyrus rectus volume in ill adult and adolescent anorexia nervosa after recovery from anorexia nervosa, and in adult bulimia nervosa. The orbitofrontal cortex is important in terminating food intake and altered function could contribute to self-starvation. The right insula, which processes taste but also interoception, was enlarged in ill adult and adolescent anorexia nervosa, as well as adults recovered from the illness. The fixed perception of being fat in anorexia nervosa could be related to altered insula function. A few studies investigated WM integrity, with the most consistent finding of reduced fornix integrity in anorexia and bulimia nervosa, a limbic pathway important in emotion but also food intake regulation. Functional brain imaging using basic sweet taste stimuli in eating disorders during the ill state or after recovery implicated repeatedly reward pathways, including insula and striatum. Brain imaging that targeted dopamine related brain activity using taste-reward conditioning tasks suggested that this circuitry is hypersensitive in anorexia nervosa, but hypo-responsive in bulimia nervosa and obesity. Those results are in line with basic research and suggest adaptive reward system changes in the human brain in response to extremes of food intake, changes that could interfere with normalization of eating behavior. PMID:25902917

  14. Advances from neuroimaging studies in eating disorders.

    Science.gov (United States)

    Frank, Guido K W

    2015-08-01

    Over the past decade, brain imaging has helped to better define eating disorder-related brain circuitry. Brain research on gray matter (GM) and white matter (WM) volumes had been inconsistent, possibly due to the effects of acute starvation, exercise, medication, and comorbidity, but newer studies have controlled for such effects. Those studies suggest larger left medial orbitofrontal gyrus rectus volume in ill adult and adolescent anorexia nervosa after recovery from anorexia nervosa, and in adult bulimia nervosa. The orbitofrontal cortex is important in terminating food intake, and altered function could contribute to self-starvation. The right insula, which processes taste but also interoception, was enlarged in ill adult and adolescent anorexia nervosa, as well as adults recovered from the illness. The fixed perception of being fat in anorexia nervosa could be related to altered insula function. A few studies investigated WM integrity, with the most consistent finding of reduced fornix integrity in anorexia and bulimia nervosa-a limbic pathway that is important in emotion but also food intake regulation. Functional brain imaging using basic sweet taste stimuli in eating disorders during the ill state or after recovery implicated repeatedly reward pathways, including insula and striatum. Brain imaging that targeted dopamine-related brain activity using taste-reward conditioning tasks suggested that this circuitry is hypersensitive in anorexia nervosa, but hyporesponsive in bulimia nervosa and obesity. Those results are in line with basic research and suggest adaptive reward system changes in the human brain in response to extremes of food intake-changes that could interfere with normalization of eating behavior. PMID:25902917

  15. Advanced studies on human gene ZNF322

    Institute of Scientific and Technical Information of China (English)

    LI Yongqing; WANG Yuequn; YUAN Wuzhou; DENG Yun; ZHU Chuanbing; WU Xiushan

    2007-01-01

    The human novel gene of ZNF322 is cloned from human fetal eDNA library using the primers on the basis of the ZNF322 sequence analyzed with computer.The gene is located on Chromosome 6p22.1,and encodes a protein consisting of 402 amino acid residues and containing nine tandem C2H2-type zinc-finger motifs.Northern blot result shows that the gene is expressed in all examined adult tissues.Subcellular location study indicates that ZNF322-EGFP fusion protein is distributed in the nucleus and cytoplasm.Reporter gene assays show that ZNF322 is a potential transcriptional activator.

  16. Development of visualization software for thermal-hydraulic analysis in a tight-lattice bundle using AVS

    International Nuclear Information System (INIS)

    Thermal-hydraulic safety in a tight-lattice bundle has been analyzed to contribute thermal design of an advanced water-cooled reactor core. Since the analytical geometry is complicated, it is difficult to understand the analysis results using general visualization software. In this study, the visualization program for the thermal-hydraulic analysis in the tight-lattice bundle was developed using the software AVS/Express. It can reproduce the three-dimensional view and graphs of the analysis results and it is helpful in understanding the thermal-hydraulic phenomena in the tight-lattice bundle. (author)

  17. Environmental restoration: Integrating hydraulic control of groundwater, innovative contaminant removal technologies and wetlands restoration--A case study at SRS

    International Nuclear Information System (INIS)

    The groundwater remediation program at the F and H Seepage Basins, Savannah River Sits (SRS) is a case study of the integration of various environmental restoration technologies at a single waste site. Hydraulic control measures are being designed to mitigate the discharge of groundwater plumes to surface water. One of the primary constituents of the plumes is tritium. An extraction and reinjection scenario is being designed to keep the tritium in circulation in the shallow groundwater, until it can naturally decay. This will be accomplished by extracting groundwater downgradient of the waste sites, treatment, and reinjection of the tritiated water into the water table upgradient of the basins. Innovative in-situ technologies, including electrolytic migration, are being field tested at the site to augment the pump-treat-reinject system. The in-situ technologies target removal of contaminants which are relatively immobile, yet represent long term risks to human health and the environment. Wetland restoration is an integral part of the F and H remediation program. Both in-situ treatment of the groundwater discharging the wetlands to adjust the pH, and replacement of water loss due to the groundwater extraction program ar being considered. Toxicity studies indicate that drought and the effects of low pH groundwater discharge have been factors in observed tree mortality in wetlands near the waste sites

  18. Recent Advances in the Studies on Luotonins

    Directory of Open Access Journals (Sweden)

    Yurngdong Jahng

    2011-06-01

    Full Text Available Luotonins are alkaloids from the aerial parts of Peganum nigellastrum Bunge. that display three major skeleton types. Luotonins A, B, and E are pyrroloquinazolino-quinoline alkaloids, luotonins C and D are canthin-6-one alkaloids, and luotonin F is a 4(3H-quinazolinone alkaloid. All six luotonins have shown promising cytotoxicities towards selected human cancer cell lines, especially against leukemia P-388 cells. Luotonin A is the most active one, with its activity stemming from topoisomerase I-dependent DNA-cleavage. Such intriguing biological activities and unique structures have led not only to the development of synthetic methods for the efficient synthesis of these compounds, but also to interest in structural modifications for improving the biological properties. Recent progress in the study of luotonins is covered.

  19. Aerodynamic optimization studies on advanced architecture computers

    Science.gov (United States)

    Chawla, Kalpana

    1995-01-01

    The approach to carrying out multi-discipline aerospace design studies in the future, especially in massively parallel computing environments, comprises of choosing (1) suitable solvers to compute solutions to equations characterizing a discipline, and (2) efficient optimization methods. In addition, for aerodynamic optimization problems, (3) smart methodologies must be selected to modify the surface shape. In this research effort, a 'direct' optimization method is implemented on the Cray C-90 to improve aerodynamic design. It is coupled with an existing implicit Navier-Stokes solver, OVERFLOW, to compute flow solutions. The optimization method is chosen such that it can accomodate multi-discipline optimization in future computations. In the work , however, only single discipline aerodynamic optimization will be included.

  20. Advances in pharmacological studies of silymarin

    Directory of Open Access Journals (Sweden)

    Yao-Cheng Rui

    1991-01-01

    Full Text Available Silymarin is the flavonoids extracted from the seeds of Silybum marianum (L Gearth as a mixture of three structural isomers: silybin, silydianin and silychristin, the former being the most active component. Silymarin protects liver cell membrane against hepatotoxic agents and improves liver function in experimental animals and humans. It is generally accepted that silymarin exerts a membrane-stabilizing action preventing or inhibiting membrane peroxidation. The experiments with soybean lipoxygenase showed that the three components of silymarin brought about a concentration-dependent non-competitive inhibition of the lipoxygenase. The experiments also showed an analogous interaction with animal lipoxygenase, thus showing that an inhibition of the peroxidation of the fatty acid in vivo was self-evident. Silybin almost completely suppressed the formation of PG at the highest concentration (0.3 mM and proved to be an inhibitor of PG synthesis in vitro. In our experiments, silybin at lower dose (65 mg/Kg decreased liver lipoperoxide content and microsomal lipoperoxidation to 84.5% and 68.55% of those of the scalded control rats respectively, and prevented the decrease of liver microsomal cytochrome p-450 content and p-nitroanisole-0-demethylase activity 24 h post-scalding. Effects of silymarin on cardiovascular systen have been studied in this university since 1980. O. O silymarin 800 mg/Kg/d or silybin 600 mg/Kg/d reduced plasma total cholesterol, LDL-C and VLDL-C. They however, enhanced HDL-C in hyperlipenic rats. Further studies showed that silymarin enhanced HDL-C in hyperlipemic rats. Further studies showed that silymarin enhanced HDL-C but didn't affect HDL-C, a property of this component which is beneficial to treatment of atherosclerosis. The results showed silymarin 80 mg or silybin 60 mg decreased in vitro platelet aggregation (porcentagem in rats. The maximal platelet aggregation induced by ADP declined significantly, and time to reach

  1. Study and Implementation of Advanced Neuroergonomic Techniques

    Directory of Open Access Journals (Sweden)

    B.F.Momin

    2012-08-01

    Full Text Available Research in the area of neuroergonomics has blossomed in recent years with the emergence of noninvasive techniques for monitoring human brain function that can be used to study various aspects of human behavior in relation to technology and work, including mental workload, visual attention, working memory, motor control, human-automation interaction, and adaptive automation. Consequently, this interdisciplinary field is concerned with investigations of the neural bases of human perception,cognition, and performance in relation to systems and technologies in the real world -- for example, in the use of computers and various other machines at home or in the workplace, and in operating vehiclessuch as aircraft, cars, trains, and ships. We will look at recent trends in functional magnetic resonance imaging (fMRI, with a special focus on the questions that have been addressed. This focus is particularly important for functional neuroimaging, whose contributions will be measured by the depth of the questions asked. The ever-increasing understanding of the brain and behavior at work in the real world, the development of theoretical underpinnings, and the relentless spread of facilitative technology in the West and abroad are inexorably broadening the substrates for this interdisciplinary area of research and practice. Neuroergonomics blends neuroscience and ergonomics to the mutual benefit of both fields, and extends the study of brain structure and function beyond the contrived laboratory settings often used in neuropsychological, psychophysical, cognitive science, and other neurosciencerelated fields. Neuroergonomics is providing rich observations of the brain and behavior at work, at home, in transportation, and in other everyday environments in human operators who see, hear, feel, attend, remember, decide, plan, act, move, or manipulate objects among other people and technology in diverse,real-world settings. The neuroergonomics approach is

  2. Conceptual Thermal Hydraulic Design of a 20MW Multipurpose Research Reactor (KAERI/VAEC joint study on a new research reactor for Vietnam)

    Energy Technology Data Exchange (ETDEWEB)

    Chae, Hee Taek; Seo, Chul Gyo; Park, Jong Hark; Park, Cheol [Kaeri, Daejeon (Korea, Republic of); Vinh, Le Vinh; Nghiem, Huynh Ton; Dang, Vo Doan Hai [Dalat Nuclear Research Reactor, Hanoi (Viet Nam)

    2007-08-15

    The conceptual thermal hydraulics design analyses for the 20 MW reference AHR core have been jointly performed by the KAERI and DNRI(VAEC). The preliminary core thermal hydraulic characteristics and safety margins for the AHR core were studied for various core flow rates, fuel assembly powers and core inlet temperatures. Statistical method was applied to the thermal hydraulic design of the reactor core. The MATRA{sub h} subchannel code has been applied to evaluate the thermal hydraulic performances of the AHR and the resulting thermal margins of the core under the forced convection cooling mode during a nominal power operation and the natural circulation mode during a reactor shutdown condition. In addition, typical accident analyses were carried out for a loss of flow accident by a primary pump seizure and a reactivity induced accident by a CAR rod withdrawal during a normal full power operation. The normal full power operation of the AHR was ensured with a sufficient safety margin for the onset of nucleate boiling phenomena. The AHR also had a sufficient natural circulation cooling capability to cool the core without the onset of nucleate boiling in the channel after a normal reactor shutdown and the anticipated transients. It was confirmed by the typical accident analyses that the AHR core was sufficiently protected from the loss of flow by the primary cooling pump seizure and the overpower transients by the CAR withdrawal from the MCHFR and fuel temperature points of view.

  3. ATF [Advanced Toroidal Facility]-2 studies

    International Nuclear Information System (INIS)

    Design studies for a low-aspect-ratio, large next-generation stellarator, ATF-II, with high-current-density, high-field, stable NbTi/Cu helical windings are described. The design parameters are an average plasma radius of 0.52 m, a major radius of 2 m, and a field on axis of 4-5 T, with 10 to 15 MW of heating power. Such a device would be comparable in scope to other next-generation stellarators but would have roughly the same aspect ratio as the tokamaks without, however, the need for current drive to sustain steady-state operation. A number of low-aspect-ratio physics issues need to be addressed in the design of ATF-II, primarily compromises between high-beta capability and good confinement properties. A six-field-period Compact Torsatron is chosen as a reference design for ATF-II, and its main features and performance predictions are discussed. An integrated (beta capability and confinement) optimization approach and optimization of superconducting windings are also discussed. 36 refs., 13 figs., 2 tabs

  4. A Study on Performance Requirements for Advanced Alarm System

    International Nuclear Information System (INIS)

    A design goals of advanced alarm system is providing advanced alarm information to operator in main control room. To achive this, we applied computer based system to Alarm System. Because, It should apply data management and advanced alarm processing(ie. Data Base Mangegment System and S/W module for alarm processing). These are not impossible in analog based alarm system. And, preexitance research examples are made on digital computer. We have digital systems for test of advanced alarm system table and have tested and studied using by test equipment in the view point of the system performance, stability and security. In this paper, we discribed about general software architecture of preexitance research examples. Also, CPU performance and requirements of system software that served to accommodate it, stability and security

  5. Neoadjuvant chemotherapy in advanced epithelial ovarian cancer: A survival study

    Directory of Open Access Journals (Sweden)

    Upasana Baruah

    2015-01-01

    Full Text Available Context: Patients with advanced ovarian cancer have a poor prognosis in spite of the best possible care. Primary debulking surgery has been the standard of care in advanced ovarian cancer; however, it is associated with high mortality and morbidity rates as shown in various studies. Several studies have discussed the benefit of neoadjuvant chemotherapy in patients with advanced ovarian cancer. Aims: This study aims to evaluate the survival statistics of the patients who have been managed with interval debulking surgery (IDS from January 2007 to December 2009. Materials and Methods: During the period from January 2007 to December 2009, a retrospective analysis of 104 patients who underwent IDS for stage IIIC or IV advanced epithelial ovarian cancer at our institute were selected for the study. IDS was attempted after three to five courses of chemotherapy with paclitaxal (175 mg/m 2 and carboplatin (5-6 of area under curve. Overall survival (OS and progression free survival (PFS were compared with results of primary debulking study from existing literature. OS and PFS rates were estimated by means of the Kaplan-Meier method. Results were statistically analyzed by IBM SPSS Statistics 19. Results: The median OS was 26 months and the median PFS was 18 months. In multivariate analysis it was found that both OS and PFS was affected by the stage, and extent of debulking. Conclusions: Neoadjuvant chemotherapy, followed by surgical cytoreduction is a promising treatment strategy for the management of advanced epithelial ovarian cancers.

  6. A review of theoretical and experimental studies underlying the thermal-hydraulic design of fast reactor fuel elements

    International Nuclear Information System (INIS)

    The economic performance of fast reactors is closely linked to the achievable burn-up of heavy atoms, that is to the endurance life of the fuel pins. The safety case must also be concerned with the integrity of the cladding, since this is the primary containment envelope for fission products. It is thus important to ensure that cladding temperatures during reactor operation are limited to levels which incur no serious impairment of mechanical properties. The function of thermal-hydraulic analysis is to provide fuel element designers with the means of achieving this objective. This paper reviews the theoretical approaches which have been developed and applied in the UK in the design of LMFBR fuel and breeder sub-assemblies, control rods and experimental clusters. It also presents results of experimental studies undertaken to develop a better understanding of coolant flow distribution and mixing problems in these components, and to provide essential data for computer codes. Problem areas in this field are highlighted, particularly the difficulties arising due to irradiation induced distortions. Reference is made to the experimental and theoretical developments which are in progress, or may be required, to provide adequate predictions of fuel pin temperatures at high burn-up. (author)

  7. A Numerical Study on the Improvement of Suction Performance and Hydraulic Efficiency for a Mixed-Flow Pump Impeller

    Directory of Open Access Journals (Sweden)

    Sung Kim

    2014-01-01

    Full Text Available This paper describes a numerical study on the improvement of suction performance and hydraulic efficiency of a mixed-flow pump by impellers. The design of these impellers was optimized using a commercial CFD (computational fluid dynamics code and DOE (design of experiments. The design variables of meridional plane and vane plane development were defined for impeller design. In DOE, variables of inlet part were selected as main design variables in meridional plane, and incidence angle was selected in vane plane development. The verification of the experiment sets that were generated by 2k factorial was done by numerical analysis. The objective functions were defined as the NPSHre (net positive suction head required, total efficiency, and total head of the impellers. The importance of the geometric design variables was analyzed using 2k factorial designs. The interaction between the NPSHre and total efficiency, according to the meridional plane and incidence angle, was discussed by analyzing the 2k factorial design results. The performance of optimally designed model was verified by experiments and numerical analysis and the reliability of the model was retained by comparison of numerical analysis and comparative analysis with the reference model.

  8. Laser/fluorescent dye flow visualization technique developed for system component thermal hydraulic studies

    International Nuclear Information System (INIS)

    A novel laser flow visualization technique is presented together with examples of its use in visualizing complex flow patterns and plans for its further development. This technique has been successfully used to study (1) the flow in a horizontal pipe subject to temperature transients, to view the formation and breakup of thermally stratified flow and to determine instantaneous velocity distributions in the same flow at various axial locations; (2) the discharge of a stratified pipe flow into a plenum exhibiting a periodic vortex pattern; and (3) the thermal-buoyancy-induced flow channeling on the shell side of a heat exchanger with glass tubes and shell. This application of the technique to heat exchangers is unique. The flow patterns deep within a large tube bundle can be studied under steady or transient conditions. This laser flow visualization technique constitutes a very powerful tool for studying single or multiphase flows in complex thermal system components

  9. Study on 3-dimensional base isolation system applying to new type power plant reactor: part 2 (hydraulic 3-dimensional base-isolation system)

    International Nuclear Information System (INIS)

    Three dimensional (3D) seismic isolation devices have been developed to use for the base isolation system of the heavy building like a nuclear reactor building. The developed seismic isolation system is composed of rolling seal type air springs and the hydraulic type springs with rocking suppression system for vertical base isolation device. In horizontal direction, the same laminated rubber bearings are used as horizontal isolation device for these systems. The performances and the applicability have already been evaluated by the technical feasibility tests and performance tests for each system. In this study, it was evaluated that the performance of the 3D base isolation system with rolling seal type air springs combined with hydraulic rocking suppression devices. In this paper, the results of performance tests for hydraulic rocking suppression system will be reported. A 1/7 scaled model of the 3D base isolation devices were manufactured and some performance test were executed for each device. For the hydraulic rocking suppression system, forced dynamic loading test was carried out in order to measure the frictional and oil flow resistance force on each cylinder. And the vibration table tests were carried out with supported weight of 228 MN in order to evaluate and to confirm the horizontal and vertical isolation performance, rocking suppression performance, and the applicability of the this seismic isolation system as the combined system. 4 rolling seal type air springs and 4 hydraulic load-carrying cylinders with rocking suppression devices supported the weight. As a result, the proposed system was verified that it could be applied to the actual nuclear power plant building to be target. (authors)

  10. Spent fluid catalytic cracking catalyst (FCC) applications in the preparation of hydraulic binders: Pozzolanic properties study

    Science.gov (United States)

    Velazquez Rodriguez, Sergio

    At the present work the replacement of Portland cement in pastes and mortars by spent fluid catalytic cracking catalyst (FCC) is studied. The study has been focused in four physicochemical characterization, hydrated lime/catalyst and cement/catalyst pastes and mortars studies, and environmental impact aspects. The FCC characterization establishes that it is a silicoaluminate, having a mainly amorphous structure, with a great specific surface, and that is necessary its mechanical activation (grinding) to obtain a pozzolanic behaviour material. The reactivity was studied by: thermogravimetry, X ray diffractometry, aqueous media electrical conductivity measurements, Fourier transform infrared spectroscopy, scanning electron microscopy, mechanical strength development evaluation and cementing effectiveness k-factor evaluation. The very high pozzolanic activity of the material has been demonstrated, besides that this reactivity has been superior to others similar products such as the metakaolin. The products formed in the hydration, pozzolanic and hydration catalysis of cement reactions have been studied, comparing the reactivity characteristics with others better known pozzolans. The nature of the reaction products between FCC and hydrated lime is similar to the ones formed by the metakaolin, being fundamentally calcium silicate hydrates and hydrated gehlenite, and their formation allow to obtain microstructures with higher mechanical strength. The possibility of preparation materials containing cement/FCC with improved mechanical strength and drying shrinkage has been demonstrated, compared to homologous materials without ground FCC. The optimal FCC dosage for the lime fixation maximization has been determined, showing a pozzolanic behaviour similar to metakaolin, nevertheless very superior to others studied pozzolans, behaviour that is improved with the aid of certain chemical activators, and with the increasing of the curing temperature. Measurements of electrical

  11. BWR-X experimental reactor for operating in remote sites (thermal-hydraulic study)

    International Nuclear Information System (INIS)

    The primary objective of this indigenous nuclear plant is to power supply no ease accessible places needed of support, like scientific bases and government facilities. What's more, design and built this particular type BWR at low pressure and temperature will give substantial background on nuclear engineering. The paper is intended to treat the nuclear reactor as a heat source in a power cycle and to study the processes by which energy is removed and converted to useful power. (author)

  12. Thermal hydraulic studies of undercooling accidents in LMFBR safety analysis: Codes and validation

    International Nuclear Information System (INIS)

    This communication is related to the LMFBR safety analysis of undercooling accidents such as pump run down or total inlet blockage of a subassembly. The authors present the physical models developed for sodium boiling propagation and clad motion and their application to SCARABEE in pile experiments simulating loss of flow accidents in bundle geometry. These studies showed the validity of our description of boiling propagation and improved our understanding of the clad relocation phenomena

  13. Study of thermal and hydraulic phenomena accompanying a rapid power excursion on a heating channel

    International Nuclear Information System (INIS)

    This document provides a study of power excursion phenomena and is divided into five sections. In the first chapter a summary of the principal research conducted world-wide on the thermal and hydrodynamic aspects of power excursions actualized either in the reactors or on installations outside of the pile is provided. In a second chapter, on the basis of the bibliographic study conducted previously, the characteristics and performance that an installation capable of correctly simulating a power excursion are indicated and the experimental device designed and developed is described with emphasis on the measurement methods used. In the third chapter the principal experimental results obtained, as well as their physical interpretation, are given. In the fourth chapter a simplified theoretical model that makes it possible to determine the manner of variation of the phenomena observed during our experiments is proposed, and in the fifth chapter what our study has added to the understanding of the phenomena that arise during a power excursion and the direction that the research should be continued is discussed. 38 refs., 69 figs

  14. In-core fuel management, safety, and thermal hydraulics studies for upgrading TRIGA MARK II research reactor

    International Nuclear Information System (INIS)

    Bangladesh Atomic Energy Commission has approved a project to upgrade the research reactor to higher flux to meet the growing demand of medical radio-isotopes production and other irradiation facilities. Preliminary studies with the various core parameters showed that it might be possible to create new irradiation flux traps, increase the neutron flux at desired location, and at the same time the fuel burn-up can be made optimal. This will need major reshuffling and reconfiguration of the core with fuel rods initially loaded. The principal objective of this study is focused to make the above improvements in the core without disturbing the safety parameters. This presentation deals with the neutronic and thermal hydraulic analysis of the 3 MW TRIGA MARK II research reactor to upgrade it to a higher flux. To realize this objective, the overall strategy followed is: (I) generation of problem dependent cross section library from basic Evaluated Nuclear Data Files such as ENDF/B-VI, JENDL 3.2 with NJOY94.10+, (ii) use WIMSD-5 package to generate cell constants for all of the materials in the core and its immediate neighborhood, (iii) use CITATION to perform 3-D global analysis of the core to study multiplication factor, neutron flux and power distribution, power peaking factors, temperature reactivity coefficients, etc., (iv) check the validity of the deterministic codes with the Monte Carlo code MCNP-4B2, (v) couple output of CITATION with PARET to study thermal hydraulic behavior to predict safety margins, and (vi) reshuffle the current core configuration to achieve the desired objectives. The computational methods, tools and techniques, customization of cross section libraries, various models for cells and super cells, and a lot of associated utilities have been standardized and established/validated for the overall core analysis. Analyses using the 4-group, and 7-group libraries of macroscopic cross sections generated from the 69-group WIMSD-5 library were performed

  15. A study on reliability of electro-hydraulic governor control system for large steam turbine in power plant

    International Nuclear Information System (INIS)

    In this work, the right management procedure for hydraulic power oil will be discussed and suggested. A thermal power plant turbine should respond to the change of load status. However, to satisfy the frequency of alternating current, the revolution per minute should be kept constant. Therefore, by controlling the flow rate of the steam to the turbine, the governor satisfies the load variation without alternating the revolution per minutes of the turbine. To protect the governor, the hydraulic power unit should be managed carefully by controlling the quality and the flow rate of the oil

  16. Determination of hydraulic conductivity of fractured rock masses: A case study for a rock cavern project in Singapore

    Directory of Open Access Journals (Sweden)

    Zhipeng Xu

    2015-04-01

    Full Text Available In order to reduce the risk associated with water seepage in an underground rock cavern project in Singapore, a reliable hydro-geological model should be established based on the in situ investigation data. The key challenging issue in the hydro-geological model building is how to integrate limited geological and hydro-geological data to determine the hydraulic conductivity of the fractured rock masses. Based on the data obtained from different stages (feasibility investigation stage, construction stage, and post-construction stage, suitable models and methods are proposed to determine the hydraulic conductivities at different locations and depths, which will be used at other locations in the future.

  17. Determination of hydraulic conductivity of fractured rock masses:A case study for a rock cavern project in Singapore

    Institute of Scientific and Technical Information of China (English)

    Zhipeng Xu; Zhiye Zhao; Jianping Sun; Ming Lu

    2015-01-01

    In order to reduce the risk associated with water seepage in an underground rock cavern project in Singapore, a reliable hydro-geological model should be established based on the in situ investigation data. The key challenging issue in the hydro-geological model building is how to integrate limited geological and hydro-geological data to determine the hydraulic conductivity of the fractured rock masses. Based on the data obtained from different stages (feasibility investigation stage, construction stage, and post-construction stage), suitable models and methods are proposed to determine the hy-draulic conductivities at different locations and depths, which will be used at other locations in the future.

  18. Study on Dynamical Simulation of Railway Vehicle Bogie Parameters Test-bench Electro-hydraulic Servo System

    Science.gov (United States)

    Lan, Zhikun; Su, Jian; Xu, Guan; Cao, Xiaoning

    Dynamical mathematical model was established for accurately positioning, fast response and real-time tracing of electro-hydraulic servo control system in railway vehicle bog ie parameters test system with elastic load. The model could precisely control the output of position and force of the hydraulic cylinders. Induction method was proposed in the paper. Dynamical simulation verified the mathematical model by SIMULINK software. Meanwhile the key factors affecting the dynamical characteristics of the system were discussed in detail. Through the simulation results, high precision is obtained in application and the need of real-time control on the railway vehicle bogie parameters test-bench is realized.

  19. A Method to Study Thickness Reduction in Electro-hydraulic Forming of Cones

    Directory of Open Access Journals (Sweden)

    Liviu Coman

    2010-10-01

    Full Text Available In this paper are presented some of the authors experimental researches connected to the electrohydroimpulses drawing of the thin conical parts made from aluminium, and also to the quality of these parts. Experimental conditions are specified and comparatively presented some results obtained for the same kind of parts, but in the case of magnetic impulses drawing (magneto – dynamic deformation. As a criterion for the quality of the parts obtained by electrohydroimpulses drawing in monoimpulse regime, the distribution of material’s thickness reduction lengthways with the cone element is adopted, for different geometries of the cone. The study is achieved for various intermediate deformation stages and discharge energies.

  20. Study on new-type packing for scram valve of hydraulic control unit

    International Nuclear Information System (INIS)

    The scram valve, which works at the emergency shutdown of BWR plant, is subjected to change in water pressure depending on plant operational status. The purpose of this study is to reduce the probability of water dripping from the shaft seal part of the valve due to the water pressure drop arising from the shutdown. We have produced a new-type packing, which have higher seal performance under the change in water pressure. We have confirmed that the gasket can be introduced to existing plants without problems from the test results for seal performance. (author)

  1. Environmental aspects of hydraulic fracturing - Main results and recommendations from two studies on behalf of the German Environment Agency

    Science.gov (United States)

    Krischbaum, Bernd; Bertram, Andreas; Böttcher, Christian; Iyimen-Schwarz, Züleyha; Rechenberg, Jörg; Dannwolf, Uwe; Meiners, Georg

    2016-04-01

    The German Environment Agency (UBA) accompanies the debate on fracking for years. Two major reports on risks and environmental impacts regarding the exploration and exploitation of unconventional natural gas, in particular shale gas have been published. On the basis of these studies as well as on scientific evidence UBA considers ecological barriers as a sustainable means to minimize the risks to environment and human health. 1) Recent studies show that the contamination of shallow aquifers by rise of fluids through natural faults or artificially created fractures is extremely unlikely. However, activities on the surface and lack of wellbore integrity pose threats and substantial risks for the quality of shallow aquifers. 2) The need for thorough groundwater monitoring is fully accepted, yet its range and design is subject to discussion. 3) Formerly, analysis and mass balances of flowback and produced water have been insufficient, thus there is a lack of exact information on proportions of frac-fluids, flowback and formation water respectively, as well as data on possible reaction products. 4) Currently, neither on national nor on European level best reference techniques (BREF) for the treatment and disposal of flowback and produced water are available. 5) In addition, land consumption, emission of greenhouse gases, and induced seismicity are major issues. UBA recommends amongst others the implementation of an environmental impact assessment (EIA) for fracking activities, the prohibition of fracking in water protection areas as well as their catchments, and the disclosure of all frac-fluid chemicals within a national chemical registry. To achieve these objectives the German Environment Agency suggests a step-by-step approach. The paper will present the main results from the studies and the recommendations of the German Environment Agency regarding hydraulic fracturing for unconventional gas exploitation.

  2. Study of ice formation in the porosity of hydraulic binder based materials

    International Nuclear Information System (INIS)

    This work concerns the nuclear waste management problematic, and aims at contributing to a better prediction of concrete freeze / thaw behaviour. Ice formation in the porosity of cement pastes and concrete was studied using differential scanning calorimetry and a thermodynamic model. It is shown that ice formation low temperatures in the pores can't be explained considering only interstitial solution under-cooling induced by crystal size restrictions, dissolved chemical elements, and containment pressures. On the other hand, taking into account the nucleation theory and the porosity division degree, three ice formation mechanisms can be defined, near -10, -25 et -40 deg. C. These results allow to explain freeze / thaw behaviour differences between blended and portland cement based materials, as well as, probably, between some high performance concrete, and allow to consider using differential scanning calorimetry as a tool for testing concrete freeze / thaw behaviour. In addition, this study highlights an irreversible shrinkage for cement pastes and concrete induced by freeze / thaw cycles without provision of water, and, on the basis of small angle neutrons scattering measures, the presence of a fractal surface type porosity in high performance cement pastes. (author)

  3. Study of a particle method for thermal-hydraulic analysis. 2

    International Nuclear Information System (INIS)

    In liquid metal fast breeder reactors (LMFBRs), liquid metal of sodium is used as the coolant under the atmospheric pressure. Thus, the coolant system has free surfaces in the components. In addition, the structures should be thin enough to reduce thermal stresses because the coolant is used in a wide range of temperature. Therefore, troubles may take place due to the sloshing, its interactions with structures and fluid-structure coupling vibration induced by flows. However, there have been no numerical methods to analyze large deformations of free surfaces and structures. Moving Particle Semi-implicit (MPS) method can be applied to topological change as well as large deformations of continuum since the calculation is based on macroscopic particles. We have developed an algorithm for incompressible flow analysis and flows with wave breaking on a free surface were successfully calculated. The objectives of the present study are development of the MPS method to analyze fluid-structure interactions and analysis of sloshing in a tank made of elastic walls. As a conclusion , a numerical method for fluid-structure interactions with large deformations of free surfaces and structures is developed based on the MPS method in the present study. (J.P.N.)

  4. Advanced stratified charge rotary aircraft engine design study

    Science.gov (United States)

    Badgley, P.; Berkowitz, M.; Jones, C.; Myers, D.; Norwood, E.; Pratt, W. B.; Ellis, D. R.; Huggins, G.; Mueller, A.; Hembrey, J. H.

    1982-01-01

    A technology base of new developments which offered potential benefits to a general aviation engine was compiled and ranked. Using design approaches selected from the ranked list, conceptual design studies were performed of an advanced and a highly advanced engine sized to provide 186/250 shaft Kw/HP under cruise conditions at 7620/25,000 m/ft altitude. These are turbocharged, direct-injected stratified charge engines intended for commercial introduction in the early 1990's. The engine descriptive data includes tables, curves, and drawings depicting configuration, performance, weights and sizes, heat rejection, ignition and fuel injection system descriptions, maintenance requirements, and scaling data for varying power. An engine-airframe integration study of the resulting engines in advanced airframes was performed on a comparative basis with current production type engines. The results show airplane performance, costs, noise & installation factors. The rotary-engined airplanes display substantial improvements over the baseline, including 30 to 35% lower fuel usage.

  5. Study of heat and hydraulic diffusions in clays under thermal loading

    International Nuclear Information System (INIS)

    This study is a cost-sharing research programme on radioactive waste disposal and radioactive waste management. The thermal conductivity of clays is the fundamental parameter which governs the thermal diffusion and the pore pressure of the rock mass under thermal loading. Experiments have been undertaken in a reduced model, respecting representative boundary conditions. They show that the thermal conductivity depends on temperature in an unfavourable sense to the decrease of heat. On the other hand, the outflow of pore water, from the source to the exterior, has a low amplitude. A single model of porous medium allows the observations and illustrates the effects of the variation of conductivity on the behaviour of rock mass. Finally, thanks to the numerical formulations specially developed, we examine the incident of the particularities of proposed models on the thermohydromechanical behaviour of geometrically simple structures subjected to a given thermal loading

  6. Open cycle OTEC thermal-hydraulic systems analysis and parametric studies

    Energy Technology Data Exchange (ETDEWEB)

    Parsons, B.; Bharathan, D.; Althof, J.

    1984-06-01

    An analytic thermohydraulic systems model of the power cycle and seawater supply systems for an open cycle ocean thermal energy conversion (OTEC) plant has been developed that allows ready examination of the effects of system and component operating points on plant size and parasitic power requirements. This paper presents the results of three parametric studies on the effects of system temperature distribution, plant gross electric capacity, and the allowable seawater velocity in the supply and discharge pipes. The paper also briefly discusses the assumptions and equations used in the model and the state-of-the-art component limitations. The model provides a useful tool for an OTEC plant designer to evaluate system trade-offs and define component interactions and performance.

  7. Open cycle OTEC thermal-hydraulic systems analysis and parametric studies

    Science.gov (United States)

    Patsons, B.; Bharathan, D.; Althof, J.

    1984-06-01

    An analytic thermohydraulic systems model of the power cycle an seawater supply systems for an open cycle ocean thermal energy conversion (OTEC) plant has been developed that allows ready examination of the effects of system and component operating points on plant size and parasitic power requirements. This paper presents the results of three parametric studies on the effects of system temperature distribution, plant gross electric capacity, and the allowable seawater velocity in the supply and discharge pipes. The paper also briefly discusses the assumptions and equations used in the model and the state-of-the-art component limitations. The model provides a useful tool for an OTEC plant designer to evaluate system trade-offs and define component interactions and performance.

  8. Study of the thermal and hydraulic phenomena occurring during power excursion on a heated test section

    International Nuclear Information System (INIS)

    The thermal and hydrodynamic phenomena occurring during a power excursion were studied in an out-of-pile loop with a water cooled channel at low pressure (1 to 4 atm. abs. ). Circular and rectangular test sections with electrically heated walls of two different thermal diffusivity materials(aluminium and stainless steel) were used. The rectangular test sections were 600 mm long, 35 mm wide and had a 2, 9 mm gap; they simulate two half plates of the M.T.R. fuel element. Natural or forced convection are possible in the test section; the water height above it can be varied from 2.8 to 8 meters and the maximum allowed pressure at its outlet is 4 atm. abs.The heating source is a series of lead batteries which is able to generate, for short periods of time, 85 volts and 25000 amperes; linear, square or exponential power rise versus time can be realized. A 14 channels tape recorder (0-10 000 Hz bandwidth; is used for the measurements of temperature (8/100 mm diameter thermocouple), pressure ('Statham' pressure transducers) and void fraction (X rays). More than 500 tests have been carried out. The influence of the initial water temperature, flow rate, pressure, water height on the water ejections, pressure variations and void fraction in the test section were studied. Tests with energies up to 3000 W/cm in 50 milliseconds were attempted. The energy above which the instabilities appear was determined. An interpretation of the observed phenomena and a simplified theoretical model are presented

  9. transient hydraulic characteristics study on nuclear reactor coolant pump during stopping period

    International Nuclear Information System (INIS)

    For the study of the transient hydrodynamics of nuclear reactor coolant pump during stopping period, Pro/E software for 3-D modeling, CFX software based on Reynolds NS equation and RNG k-ε equation were used to simulate the transient characteristics of nuclear reactor coolant pump impeller flow path during stopping period. The vortex in the impeller outlet is less than that in the impeller inlet. The vortex of the impeller outlet influenced by the static interference between the impeller and guide vane shows the periodic substantial fluctuations. The vortex in the junction between the pump body and outlet pipe is large, and the vortex in the opposite direction of the guide vane is the largest. The radial force of linear turning down model shows a periodic fluctuation and gradual decrease. Turning down model with the idler wheel has the same tendency as the linear turning down model though the change amplitude is less than that of radial force for linear turning down model. Especially while the parameter t/T is 0.6-1, the radial force is close to 0. The radial force of regular turning down model shows an irregular change. When the parameter t/T is 0.25, its radial force is the largest, which has great influence on the reliability of nuclear reactor coolant pump. (authors)

  10. Experimental study on the refined thermal-hydraulics of a sodium flow across a tube row

    International Nuclear Information System (INIS)

    This paper presents experimental results obtained in an in-sodium mock-up, made of 30 electrically heated tubes, devoted to the analysis of heat transfer and temperature fluctuations. Three parameters have been studied: mean temperature level (from 350 deg C to 470 deg C), REYNOLDS number (6600 to 63000) and heat flux density (100 to 600 kW/m2). The mean temperature field is quite homogeneous, due to the strong conduction. High temperature fluctuations are noticed. These fluctuations increase with the heat flux. They are lower and with a gaussian Density Probability Function for the lowest and the highest REYNOLDS number values. They are higher (with a maximum peak-to-peak value of 70 deg C) for REYNOLDS numbers around 9000; for this value, the spectra contains a periodic component (with a STROUHAL number equal to 0.3), and the distribution can have either a gaussian, or a ''double peak'', or an intermediate shape. (authors). 11 figs., 16 refs

  11. Study on thermal-hydraulic behavior during molten material and coolant interaction

    International Nuclear Information System (INIS)

    In a core disruptive accident (CDA) of a Fast Breeder Reactor, the post accident heat removal (PAHR) is crucial for the accident mitigation. The molten core material should be solidified in the lower plenum of the reactor vessel. The material, being fragmented while solidification and forming debris bed, will be cooled in sodium coolant. It is still unknown whether the coolant vapor generation will promote or disturb the solidification and fragmentation process. The purpose of the present study is to experimentally clarify the capability of the coolant for solidification and fragmentation of the molten material including coolant boiling. In the experiment, molten metal jet is injected into water to experimentally obtain the visualized information of the fragmentation and boiling phenomena during PAHR in CDA. The jet ejection experiment shows that the break up of the molten material into fine fragments are observed at the top, side and middle part of the jet during very short time interval. The distributed particle behavior of the molten material jet is observed with high-speed video camera. And the visual data is analyzed with PIV. Consequently, it is confirmed that the PIV analysis is useful to quantitatively evaluate the underwater flow field of the molten material. (author)

  12. Numerical study on hydraulic performance of submerged propellers in oxidation ditch

    Institute of Scientific and Technical Information of China (English)

    Wu Siyuan; Zhou Daqing; Zheng Yuan

    2014-01-01

    The submerged propeller is an efficient diving mix device,which is applicable for oxidation ditch treatment in industry,city and village wastewater-treatment plant.The impeller structure and reasonable rotating speed are important factors that determine flow field distribution and energy conver-sion efficiency.So it is necessary to use modern design methods to develop new kinds of high efficiency submerged propellers,and research the flow field characteristics of submerged propellers.On the basis of the existing form drawing,three-dimensional model of submerged propellers and unstructured tetra-hedral mesh were generated.Based on Navier -Stokes equations and standard k -εturbulence model, the flow was simulated by using a simple algorithm.Through changing some design parameters of pro-pellers,the corresponding numerical simulation results reveal that for the same impeller diameter and service area of submerged propellers,the power consumption could be reduced effectively by optimizing blade mounting angle,which can determine the best blade mounting angle and most suitable rotational speed under given conditions.The study can provide theoretical and project guidance for submerged propellers design.

  13. Advanced dementia research in the nursing home: the CASCADE study.

    Science.gov (United States)

    Mitchell, Susan L; Kiely, Dan K; Jones, Richard N; Prigerson, Holly; Volicer, Ladislav; Teno, Joan M

    2006-01-01

    Despite the growing number of persons with advanced dementia, and the need to improve their end-of-life care, few studies have addressed this important topic. The objectives of this report are to present the methodology established in the CASCADE (Choices, Attitudes, and Strategies for Care of Advanced Dementia at the End-of-Life) study, and to describe how challenges specific to this research were met. The CASCADE study is an ongoing, federally funded, 5-year prospective cohort study of nursing [nursing home (NH)] residents with advanced dementia and their health care proxies (HCPs) initiated in February 2003. Subjects were recruited from 15 facilities around Boston. The recruitment and data collection protocols are described. The demographic features, ownership, staffing, and quality of care of participant facilities are presented and compared to NHs nationwide. To date, 189 resident/HCP dyads have been enrolled. Baseline data are presented, demonstrating the success of the protocol in recruiting and repeatedly assessing NH residents with advanced dementia and their HCPs. Factors challenging and enabling implementation of the protocol are described. The CASCADE experience establishes the feasibility of conducting rigorous, multisite dementia NH research, and the described methodology serves as a detailed reference for subsequent CASCADE publications as results from the study emerge. PMID:16917187

  14. Numerical and experimental studies of hydraulic noise induced by surface dipole sources in a centrifugal pump

    Institute of Scientific and Technical Information of China (English)

    刘厚林; 戴菡葳; 丁剑; 谈明高; 王勇; 黄浩钦

    2016-01-01

    The influences of the four different surface dipole sources in a centrifugal pump on the acoustic calculating accuracy are studied in this paper, by using the CFD combined with the Lighthill acoustic analogy methods. Firstly, the unsteady flow in the pump is solved based on the large eddy simulation method and the pressure pulsations on the four different surfaces are obtained. The four surfaces include the volute surface, the discharge pipe surface, the inner surface of the pump cavity, and the interfaces between the impeller and the stationary parts as well as the outer surface of the impeller. Then, the software Sysnoise is employed to interpolate the pressure fluctuations onto the corresponding surfaces of the acoustic model. The Fast Fourier Transform with a Hanning window is used to analyze the pressure fluctuations and transform them into the surface dipole sources. The direct boundary element method is applied to calculate the noise radiated from the dipole sources. And the predicted sound pressure level is compared with the experi- mental data. The results show that the pressure fluctuations on the discharge pipe surface and the outer surface of the impeller have little effect on the acoustic simulation results. The pressure pulsations on the inner surface of the pump cavity play an important role in the internal flow and the acoustic simulation. The acoustic calculating error can be reduced by about 7% through considering the effect of the pump cavity. The sound pressure distributions show that the sound pressure level increases with the growing flow rate, with the largest magnitude at the tongue zone.

  15. A fundamental study for safety in advanced PWR systems

    Energy Technology Data Exchange (ETDEWEB)

    Park, Goon Cherl; Kang, C. S.; Lee, E. C.; Kim, S. N.; Lee, J. S.; Kim, M. H.; Chae, W. S.; Kim, M. H.; Lee, D. H.; No, S. T.; Jeon, G. D.; Lee, T. H.; Kim, B. S.; Park, H. J.; Yoon, J. I.; Kim, J. H.; Jeon, J. H.; Jang, W. H.; Sa, Y. C.; Lee, H. W.; Kim, S. J.; Kim, J. W.; Kim, Y. H.; Lee, S. W.; Yang, C. G.; Kim, Y. S.; Ha, J. B.; Son, M. S.; An, Y. C.; Bae, S. W. [Seoul National University, Seoul (Korea, Republic of)

    1997-07-01

    For the development of integral type small and medium reactor which is remarkably safer than existing plants, the operability of passive safety systems should be studied and its applicability to the integral type reactor should be evaluated. The purposes of this study are to evaluate the characteristics of various passive safety systems and provide the proper data for the future design with performing experiments and developing analytical methodology. Thus in this study, the following techniques for small reactors and passive safety systems subject to this study are evaluated and a part of basic experiments and numerical works necessary to the experiments were performed, First, heat pipes used in containment vessel which removes hear by passive mechanism during accidents, second, natural circulation characteristics for the passive safety analysis of integrated reactor, third, heat evaluation of the effective function of hydraulic valve in passive decay heat removal systems, fifth, the determination of the improved source term for the integral reactor, and the last, passive containment cooling system, which is the first step in the analysis of the integrated safety and the environmental impacts of nuclear power plant. 184 refs., 49 tabs., 188 figs. (author)

  16. Selective perceptions of hydraulic fracturing.

    Science.gov (United States)

    Sarge, Melanie A; VanDyke, Matthew S; King, Andy J; White, Shawna R

    2015-01-01

    Hydraulic fracturing (HF) is a focal topic in discussions about domestic energy production, yet the American public is largely unfamiliar and undecided about the practice. This study sheds light on how individuals may come to understand hydraulic fracturing as this unconventional production technology becomes more prominent in the United States. For the study, a thorough search of HF photographs was performed, and a systematic evaluation of 40 images using an online experimental design involving N = 250 participants was conducted. Key indicators of hydraulic fracturing support and beliefs were identified. Participants showed diversity in their support for the practice, with 47 percent expressing low support, 22 percent high support, and 31 percent undecided. Support for HF was positively associated with beliefs that hydraulic fracturing is primarily an economic issue and negatively associated with beliefs that it is an environmental issue. Level of support was also investigated as a perceptual filter that facilitates biased issue perceptions and affective evaluations of economic benefit and environmental cost frames presented in visual content of hydraulic fracturing. Results suggested an interactive relationship between visual framing and level of support, pointing to a substantial barrier to common understanding about the issue that strategic communicators should consider. PMID:26399946

  17. Plug & Play Control of Hydraulic Networks

    DEFF Research Database (Denmark)

    Jensen, Tom Nørgaard

    2012-01-01

    Process Control research program, which the work presented here is a part of. An industrial case study involving a large-scale hydraulic network with non-linear dynamics is studied. The hydraulic network underlies a district heating system, which provides heating water to a number of end-users in a city...

  18. An Appraisal of Qualifying Role of Hydraulic Heritage Systems: A Case Study of Qanat in the Central Iran

    NARCIS (Netherlands)

    Fasihi Harandi, M.; De Vries, M.J.

    2014-01-01

    Hydraulic heritage systems, both underground and exposed, have been known to be sustainable for millennia. Persian and also Roman aqueducts are examples of such hydrosystems. Their value is often overlooked but they have undeniable advantages: they have functional interconnectedness with their surro

  19. A study on the effects of different hydraulic loading rates (HLR) on pollutant removal efficiency of subsurface horizontal-flow constructed wetlands used for treatment of domestic wastewaters.

    Science.gov (United States)

    Çakir, Recep; Gidirislioglu, Ali; Çebi, Ulviye

    2015-12-01

    The research into the treatment of domestic wastewaters originating from Büyükdöllük village in Edirne Province was carried out over a 3 year experimental period. The wastewaters of the settlement were treated using a constructed wetland with subsurface horizontal flow, and the effects of different hydraulic loading levels on removal efficiency were studied. In order to achieve this goal, three equal chambers (ponds) of 300 m(2) each were constructed and planted with Phragmites australis. Each of the chambers was loaded with domestic wastewater with average flow discharge creating hydraulic loading rates of 0. m(3) day(-1) m(-2); 0.075 m(3) day(-1) m(-2) and 0.125 m(3) day(-1) m(-2), respectively. According to the results of the study, the inlet levels of the pollutant parameters with carbon origin in the water samples taken from the system entrance are high and the average values for three years are respectively: Biological Oxygen Demand, BOD5 -324.5 mg L(-1); Chemical Oxygen Demand, COD -484,0 mg L(-1); suspended solids (TSS) -147.3 mg L(-1) and Oil and Grease -0.123 mg L(-1). It was also determined that the removal rates of the system were closely dependent on the applied hydraulic loading levels and the highest removal rates of 64.9%, 62.5%, 86.3% and 80.34% for BOD5, COD, TSS and Oil and Grease, respectively, were determined in the pond with a hydraulic loading rate of 0.050 m(3) day(-1) m(-2). Lower removal of 57.9%, 55.5%, 81.4% and 74.5% for BOD5, COD, TSS and Oil and Grease were recorded in the pond with a hydraulic loading rate of 0.075 m(3) day(-1) m(-2); and these values were 49.1%, 47.8%, 70.9% and 62.1% for the pond with a hydraulic loading rate of 0.125 m(3) day(-1) m(-2). High removal rates were also recorded for the other investigated pollution parameters. PMID:26363259

  20. [Advances in Genomics Studies for Coronary Artery Disease].

    Science.gov (United States)

    Wang, Ying; Zhu, Hui-juan; Zeng, Yong

    2015-08-01

    Coronary artery disease (CAD) is one of the major life-threatening diseases. In addition to traditional risk factors including age, sex, smoking, hypertension,and diabetes, genomic studies have shown that CAD has obvious genetic predisposition. In recent years, the rapid advances in genomics shed new light on early diagnosis, risk stratification and new treatment targets. PMID:26564468

  1. Design study on advanced reprocessing systems for FR fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, H.; Kawamura, F.; Nishimura, T.; Kamiya, M. [Japan Nuclear Cycle Development Institute, Ibaraki (Japan)

    2001-07-01

    A design study has been carried out for four advanced reprocessing technologies for the future fast rector (FR) recycle systems (advanced aqueous, and three non-aqueous systems based on oxide electrowinning, metal electrorefining, and fluoride volatility methods). The systems were evaluated mainly from the viewpoint of economics. It has been shown that, for MOX fuel reprocessing, all the systems with a capacity of 200 t/y attains the economical target, whereas for such a small capacity as 50 t/y, only the non-aqueous systems have potential to attain the target. For metallic and nitride fuel, a metal electrorefining system has been shown to be advantageous. (author)

  2. From "fixing women" to "institutional transformation": An ADVANCE case study

    Science.gov (United States)

    Yennello, Sherry; Kaunas, Christine

    2015-12-01

    The United States' position in the global economy requires an influx of women into science, technology, engineering, and mathematics (STEM) fields in order to remain competitive. Despite this, the representation of women in STEM continues to be low. The National Science Foundation's ADVANCE Program addresses this issue by funding projects that aim to increase the representation of women in academic STEM fields through transformation of institutional structures that impede women's progress in academic STEM fields. This paper includes a case study of the Texas A&M University ADVANCE Program.

  3. Design study on advanced reprocessing systems for FR fuel cycle

    International Nuclear Information System (INIS)

    A design study has been carried out for four advanced reprocessing technologies for the future fast rector (FR) recycle systems (advanced aqueous, and three non-aqueous systems based on oxide electrowinning, metal electrorefining, and fluoride volatility methods). The systems were evaluated mainly from the viewpoint of economics. It has been shown that, for MOX fuel reprocessing, all the systems with a capacity of 200 t/y attains the economical target, whereas for such a small capacity as 50 t/y, only the non-aqueous systems have potential to attain the target. For metallic and nitride fuel, a metal electrorefining system has been shown to be advantageous. (author)

  4. Methods for studying fuel management in advanced gas cooled reactors

    International Nuclear Information System (INIS)

    The methods used for studying fuel and absorber management problems in AGRs are described. The basis of the method is the use of ARGOSY lattice data in reactor calculations performed at successive time steps. These reactor calculations may be quite crude but for advanced design calculations a detailed channel-by-channel representation of the whole core is required. The main emphasis of the paper is in describing such an advanced approach - the ODYSSEUS-6 code. This code evaluates reactor power distributions as a function of time and uses the information to select refuelling moves and determine controller positions. (author)

  5. Introductory study of the usability of the Fluent code. Possibilities of application to thermal-hydraulic analyses of reactor containments. Rev. 0

    International Nuclear Information System (INIS)

    The feasibility of applying the Fluent 5.0.3 CFD (Computational Fluid Dynamics) code to thermal hydraulic analyses of reactor containments is discussed and illustrated on 3 cases: (1) calculation of the velocity field in the vessel during steam inflow, (2) pipe wall washing with water, and (3) air flow through the check valve. The studies concerned really existing equipment, although the boundary conditions were simplified substantially. (P.A.)

  6. Study of hydraulic and toxic shocks in two anaerobic-aerobic Pilot Moving Bed Biofilm Reactors used for nitrification and denitrification

    International Nuclear Information System (INIS)

    Pilot Moving Bed Biofilm Reactors fed on synthetic wastewater, were used in order to study nitrification and denitrification of high concentration wastewater. To investigate the stability of the nitrification and denitrification process in moving bed biofilm systems, a hydraulic shock and a toxic shock were applied to the system. These two systems showed high stability and process efficiency did not change significantly, in spite of intensive variation during the applied shocks

  7. Erratum to "SWASHES: a compilation of Shallow Water Analytic Solutions for Hydraulic and Environmental Studies" [Int. J. Numer. Meth. Fluids, 2013, 72 (3), 269-300

    OpenAIRE

    Delestre, Olivier; Lucas, Carine; Ksinant, Pierre-Antoine; Darboux, Frédéric; Laguerre, Christian; Vo, Thi Ngoc Tuoi; James, François; Cordier, Stéphane

    2014-01-01

    Numerous codes are being developed to solve shallow water equations. Because these are used in hydraulic and environmental studies, their capability to simulate flow dynamics properly is critical to guarantee infrastructure and human safety. Although validating these codes is an important issue, code validations are currently restricted because analytic solutions to the shallow water equations are rare and have been published on an individual basis over a period of more than five decades. Thi...

  8. Numerical simulation study on turbulence of hydraulic jump with low Froude number%低佛氏数水跃紊流数值模拟研究

    Institute of Scientific and Technical Information of China (English)

    张春财; 杜宇

    2012-01-01

    【Objective】The research studied the hydraulic jump characteristic of low Froude number.【Method】By using VOF method in water surface upstream and downstram of the gate and 2-d k-ε RNG turbulence model,hydraulic jump with low Froude number(Fr1=2.0-4.5) was simulated numerically.Water depth after hydraulic jump,length of hydraulic jump and distribution of flow velocity of hydraulic jump with low Froude number were analyzed.Furthermore,pressure,turbulent kinetic energy,turbulent dissipation and coefficient of energy dissipation in the hydraulic jump region and the open cannel flow region were studied.【Result】The length of hydraulic jump whose degree of submergence is more than 1.2 is longer than that of calculated by empirical formula,and increases along with the increase of Froude number.The maximum velocity reduces along the flowing of the main flow in the hydraulic jump region,and the reduction of the average velocity in section is small in open channel flow region after hydraulic jump.The pressure distribution of hydraulic jump is closely related to flow aeration.Turbulent kinetic energy and coefficient of energy dissipation are the maximum near the boundary of the main flow and ground droller in the hydraulic jump.The higher the Froude number is,the higher the theoretical and practical coefficient of energy dissipation is.The theory coefficient of energy dissipation is higher than actual coefficient considering the turbulent kinetic energy after hydraulic jump.【Conclusion】Because low-head key water control project has larger flood discharge power,less energy dissipation hydraulic characteristic of hydraulic jump with low Froude number should be seriously considered,and reasonable energy dissipation instrument should be designed to solve its problems of energy dissipation and erosion-control.%【目的】研究低佛氏数(Fr。)水跃紊流的水力特性。【方法】采用VOF方法处理闸门上、下游表面,用二维RNG型肛e

  9. Study on local thermal–hydraulic performance and optimization of zigzag-type printed circuit heat exchanger at high temperature

    International Nuclear Information System (INIS)

    Highlights: • Flow and temperature at high temperature cannot be fully-developed. • Non-dimensional velocity and temperature are proposed to evaluate performances. • Local Nusselt number and friction factor at high and low temperature are similar. • Bigger inclined angle should be used in cold region when using hybrid channels. • Optimal inclined angles are depended on operating conditions. - Abstract: High temperature heat exchanger is one of the most important components to transfer heat from the first loop to the second loop in the very high temperature reactor in nuclear energy application. In order to enhance the heat transfer performance, a mini-channel heat exchanger called printed circuit heat exchanger has attracted more attention in recent years. In this paper, the thermal–hydraulic performance of zigzag-type printed circuit heat exchanger with helium as the working fluid operating at the typical temperature of 900 °C in the very high temperature reactor is studied. It is found that the flow and temperature at high temperature cannot achieve a fully-developed condition due to the significant variation of thermal physical properties arisen from the large temperature difference. However, the non-dimensional velocity and temperature can become steady after the second pitch and is similar to the fluid flow behaviors at low temperature. Therefore the local Nusselt number and friction factor at high temperature can match well with those at low temperature when the Reynolds number is bigger than 900. With the increase of inclined angle, the heat transfer and pressure drop increase. It is recommended to put the channel with a larger inclined angle to the cold region when using the hybrid channels. The heat transfer enhancement method with inclined angles completely depends on the operating conditions

  10. Characterizing hydraulic conductivity with the direct-push permeameter

    Science.gov (United States)

    Butler, J.J., Jr.; Dietrich, P.; Wittig, V.; Christy, T.

    2007-01-01

    The direct-push permeameter (DPP) is a promising approach for obtaining high-resolution information about vertical variations in hydraulic conductivity (K) in shallow unconsolidated settings. This small-diameter tool, which consists of a short screened section with a pair of transducers inset in the tool near the screen, is pushed into the subsurface to a depth at which a K estimate is desired. A short hydraulic test is then performed by injecting water through the screen at a constant rate (less than 4 L/min) while pressure changes are monitored at the transducer locations. Hydraulic conductivity is calculated using the injection rate and the pressure changes in simple expressions based on Darcy's Law. In units of moderate or higher hydraulic conductivity (more than 1 m/d), testing at a single level can be completed within 10 to 15 min. Two major advantages of the method are its speed and the insensitivity of the K estimates to the zone of compaction created by tool advancement. The potential of the approach has been assessed at two extensively studied sites in the United States and Germany over a K range commonly faced in practical field investigations (0.02 to 500 m/d). The results of this assessment demonstrate that the DPP can provide high-resolution K estimates that are in good agreement with estimates obtained through other means. ?? 2007 National Ground Water Association.

  11. Thermal-hydraulic unreliability of passive systems

    International Nuclear Information System (INIS)

    Advanced light water reactor designs like AP600 and the simplified boiling water reactor (SBWR) use passive safety systems for accident prevention and mitigation. Because these systems rely on natural forces for their operation, their unavailability due to hardware failures and human error is significantly smaller than that of active systems. However, the coolant flows predicted to be delivered by these systems can be subject to significant uncertainties, which in turn can lead to a significant uncertainty in the predicted thermal-hydraulic performance of the plant under accident conditions. Because of these uncertainties, there is a probability that an accident sequence for which a best estimate thermal-hydraulic analysis predicts no core damage (success sequence) may actually lead to core damage. For brevity, this probability will be called thermal-hydraulic unreliability. The assessment of this unreliability for all the success sequences requires very expensive computations. Moreover, the computational cost increases drastically as the required thermal-hydraulic reliability increases. The required computational effort can be greatly reduced if a bounding approach can be used that either eliminates the need to compute thermal-hydraulic unreliabilities, or it leads to the analysis of a few bounding sequences for which the required thermal-hydraulic reliability is relatively small. The objective of this paper is to present such an approach and determine the order of magnitude of the thermal-hydraulic unreliabilities that may have to be computed

  12. Control issues for a hydraulically powered dissimilar teleoperated system

    International Nuclear Information System (INIS)

    This paper will address two issues associated with the implementation of a hydraulically powered dissimilar master-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented. (Schilling's Titan II hydraulic manipulators are the slave manipulators and the master manipulators are from the Oak Ridge National Laboratory-developed Advanced Servo Manipulator.)

  13. Control issues for a hydraulically powered dissimilar teleoperated system

    Energy Technology Data Exchange (ETDEWEB)

    Jansen, J.F.; Kress, R.L.

    1995-12-31

    This paper will address two issues associated with the implementation of a hydraulically powered dissimilar master-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented. (Schilling`s Titan II hydraulic manipulators are the slave manipulators and the master manipulators are from the Oak Ridge National Laboratory-developed Advanced Servo Manipulator.)

  14. A three dimensional two energy group coupled reactor physics and thermal hydraulics code (M32) - A tool for student design studies

    International Nuclear Information System (INIS)

    This paper describes a new code M32 that has been developed to perform coupled reactor physics and thermal hydraulic calculations undertaken in student reactor design studies. M32 is a general three-dimensional, two-energy group code that couples a diffusion theory representation of the core with a thermal hydraulic description that accounts for the heat flux and coolant enthalpy rise. A sample application examining the feasibility of a high temperature helium cooled reactor based on the General Atomics GT-MHR design for marine applications is described. M32 has been demonstrated to be a useful addition to the portfolio of computational tools for education and training in reactor design methodologies. British Crown Copyright 2004/MOD. (authors)

  15. NATO Advanced Study Institute on Recent Advances in the Modeling of Hydrologic Systems

    CERN Document Server

    O’Connell, P

    1991-01-01

    Modeling of the rainfall-runoff process is of both scientific and practical significance. Many of the currently used mathematical models of hydrologic systems were developed a genera­ tion ago. Much of the effort since then has focused on refining these models rather than on developing new models based on improved scientific understanding. In the past few years, however, a renewed effort has been made to improve both our fundamental understanding of hydrologic processes and to exploit technological advances in computing and remote sensing. It is against this background that the NATO Advanced Study Institute on Recent Advances in the Modeling of Hydrologic Systems was organized. The idea for holding a NATO ASI on this topic grew out of an informal discussion between one of the co-directors and Professor Francisco Nunes-Correia at a previous NATO ASI held at Tucson, Arizona in 1985. The Special Program Panel on Global Transport Mechanisms in the Geo-Sciences of the NATO Scientific Affairs Division agreed to sp...

  16. Definition study for temperature control in advanced protein crystal growth

    Science.gov (United States)

    Nyce, Thomas A.; Rosenberger, Franz; Sowers, Jennifer W.; Monaco, Lisa A.

    1990-01-01

    Some of the technical requirements for an expedient application of temperature control to advanced protein crystal growth activities are defined. Lysozome was used to study the effects of temperature ramping and temperature gradients for nucleation/dissolution and consecutive growth of sizable crystals and, to determine a prototype temperature program. The solubility study was conducted using equine serum albumin (ESA) which is an extremely stable, clinically important protein due to its capability to bind and transport many different small ions and molecules.

  17. Promoting water hydraulics in Malaysia: A green educational approach

    Science.gov (United States)

    Yusof, Ahmad Anas; Zaili, Zarin Syukri; Hassan, Siti Nor Habibah; Tuan, Tee Boon; Saadun, Mohd Noor Asril; Ibrahim, Mohd Qadafie

    2014-10-01

    In promoting water hydraulics in Malaysia, this paper presents research development of water hydraulics educational training system for secondary and tertiary levels in Malaysia. Water hydraulics trainer with robotic attachment has been studied in order to promote the usefulness of such educational tools in promoting sustainability and green technology in the country. The trainer is being developed in order to allow constructive curriculum development and continuous marketing research for the effectiveness and usefulness of using water in hydraulic power trainer. The research on water-based hydraulic trainer is now possible with the current development in water hydraulics technology.

  18. Hydraulic properties of ladle slags

    Directory of Open Access Journals (Sweden)

    J. Vlček

    2016-07-01

    Full Text Available The article presents results of examining of hydraulic properties of ladle slags formed during production of steel. The studied ladle slags were subjected to different cooling mode from the molten state. Based on the ability of the slag react with the water was assessed their hydraulic activity. The hydraulic properties are caused by the presence of minerals dicalcium silicate, tricalcium aluminate, mayenite, brownmillerite and dicalcium ferite. The emergence of required hydrating phases in the ladle slags is conditioned by a sufficient CaO content and their cooling rate. The contact the slag with water during processing and their ageing has a negative effect. The experiment has shown that the phase transformation of the mineral dicalcium silicate which occurs during cooling of the ladle slags cause their volume instability.

  19. NATO Advanced Study Institute on Methods in Computational Molecular Physics

    CERN Document Server

    Diercksen, Geerd

    1992-01-01

    This volume records the lectures given at a NATO Advanced Study Institute on Methods in Computational Molecular Physics held in Bad Windsheim, Germany, from 22nd July until 2nd. August, 1991. This NATO Advanced Study Institute sought to bridge the quite considerable gap which exist between the presentation of molecular electronic structure theory found in contemporary monographs such as, for example, McWeeny's Methods 0/ Molecular Quantum Mechanics (Academic Press, London, 1989) or Wilson's Electron correlation in moleeules (Clarendon Press, Oxford, 1984) and the realization of the sophisticated computational algorithms required for their practical application. It sought to underline the relation between the electronic structure problem and the study of nuc1ear motion. Software for performing molecular electronic structure calculations is now being applied in an increasingly wide range of fields in both the academic and the commercial sectors. Numerous applications are reported in areas as diverse as catalysi...

  20. Simulation Study on the Hydraulic System Fault Injection%液压系统故障注入仿真研究

    Institute of Scientific and Technical Information of China (English)

    丁遥; 陈小虎; 阳能军; 高淑祥

    2014-01-01

    The control method is an important part of the fault injection studies. PID controller was introduced into the hydraulic system,the parameter was established using MATLAB/Simulink simulation,the results proved that PID control could improve the sys-tem performance effectively. Then the hydraulic system simulation model based on PID control was established using AMESim software. Hydraulic cylinder fault injection was realized through parameter settings. Conclusions were obtained which were required through a lot of experiments before.%控制是故障注入研究的重要部分。将PID控制器引入液压系统控制,利用MATLAB/Simulink仿真软件进行仿真,确立了控制参数,证明了PID控制能有效改善系统的响应性能,然后利用AMESim软件建立了基于PID控制的液压系统仿真模型,通过参数设置实现了液压缸故障注入,得到了需要大量实验得出的结论。

  1. Comparative study on the characteristics of AC, DC servomotors and hydraulic motors; Dendoki to yuatsu motor no tokusei taihi ni kansuru chosa kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Konno, Y. [Shibaura Inst. of Tech., Tokyo (Japan); Nakano, K.

    1997-07-15

    The relationship of the output torque and power rate of the electric motor with the inertial moment and the mass of the motor is investigated, and the validity of the study is verified in reference to the specifications given in catalogs. Based on the result of the investigation, comparison with the characteristics of the hydraulic motor is carried out. Paying attention particularly to smaller size, lighter weight and accelerating performance of the AC and DC servomotors and the hydraulic motor, the relation among the data, rated values and performance of motors by the assumption based on the performance principle is exhibited to clarify the comparison of the performance. It is made clear that the relationships hold good with the catalog data of actual machines not only for DC motors but also for AC motors. In addition, similar relationships are obtained for the hydraulic motor, and it is made clear that they agree with the result of the investigation. The tendency of distribution based on the relationships among data, rated values and performance of motors obtained by inference is given in this report. 18 refs., 7 figs., 1 tab.

  2. Large-scale simulations on thermal-hydraulics in fuel bundles of advanced nuclear reactors (Annual Report of the Earth Simulator Center, Dec 2008, 2007 issue)

    International Nuclear Information System (INIS)

    In order to predict the water-vapor two-phase flow dynamics in a fuel bundle of an advanced light-water reactor, large-scale numerical simulations were performed using a highly parallel-vector supercomputer, the earth simulator. Although conventional analysis methods such as subchannel codes and system analysis codes need composition equations based on the experimental data, it is difficult to obtain high prediction accuracy when experimental data to obtain the composition equations. Then, the present large-scale direct simulation method of water-vapor two-phase flow was proposed. The void fraction distribution in a fuel bundle under boiling heat transfer condition was analyzed and the bubble dynamics around the fuel rod surface were predicted quantitatively. (author)

  3. Determination of hydraulic conductivity of fractured rock masses: A case study for a rock cavern project in Singapore

    OpenAIRE

    Zhipeng Xu; Zhiye Zhao; Jianping Sun; Ming Lu

    2015-01-01

    In order to reduce the risk associated with water seepage in an underground rock cavern project in Singapore, a reliable hydro-geological model should be established based on the in situ investigation data. The key challenging issue in the hydro-geological model building is how to integrate limited geological and hydro-geological data to determine the hydraulic conductivity of the fractured rock masses. Based on the data obtained from different stages (feasibility investigation stage, constru...

  4. An Appraisal of Qualifying Role of Hydraulic Heritage Systems: A Case Study of Qanat in the Central Iran

    OpenAIRE

    M Fasihi Harandi; De Vries, M.J.

    2014-01-01

    Hydraulic heritage systems, both underground and exposed, have been known to be sustainable for millennia. Persian and also Roman aqueducts are examples of such hydrosystems. Their value is often overlooked but they have undeniable advantages: they have functional interconnectedness with their surrounding society and ecology, which sometimes leads to revitalization plans. By using the notion ‘qualifying role’, this paper will raise questions concerning the disregarded functions and early and ...

  5. Hydraulic Yaw System

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Mørkholt, M.

    system and rotor shaft when utilizing the soft yaw drive concept compared to the original stiff yaw system. The physical demands of the hydraulic yaw system are furthermore examined for a life time of 20 years. Based on the extrapolated loads, the duty cycles show that it is possible to construct...... a hydraulic soft yaw system, which is able to reduce the loads on the wind turbine significantly. A full scale hydraulic yaw test rig is available for experiments and tests. The test rig is presented as well as the system schematics of the hydraulic yaw system....

  6. Thermal-Hydraulics Research in the Valencia Polytechnic University

    International Nuclear Information System (INIS)

    The research on thermal-hydraulics at the Polytechnic University of Valencia is performed by the TIN group (thermal-hydraulic and Nuclear Engineering). The group activities are currently carried out at the Energy Engineering Institute. The main research topics are: transient analysis of reactors, nuclear reactor stability, passive and advanced safety reactors, two-phase flow in nuclear reactors. (Author)

  7. Hydraulics and pneumatics: don`t blow your money

    Energy Technology Data Exchange (ETDEWEB)

    Davis, B.

    1997-09-25

    The significant savings obtained when operating air compressors and hydraulic systems using variable speed drives and new designs are noted. Details are given of recent advances in air compressor technology such as the SSR 2-stage rotary air compressor and the Cyclon 475SR(speed regulation) rotary screw compressor. The UK hydraulics and pneumatics markets are discussed. (UK)

  8. Experimental Study of Crack Initiation and Extension Induced by Hydraulic Fracturing in a Tree-Type Borehole Array

    Directory of Open Access Journals (Sweden)

    Yiyu Lu

    2016-06-01

    Full Text Available High-pressure hydraulic fracturing technology in coal and coal bed methane mines can lead to roof and floor damage, and fracture initiation disorder that leads to a “blank area”, and other issues. A new method of hydraulic fracturing is proposed to increase the homogeneous permeability of coal in underground coalmines. Numerical and other simulation tests for different forms of a tree-type, branched borehole model are presented. The results show that the branched array causes cracks to initiate from the bottom of the array, and these extend along the direction of the adjacent boreholes. Generally, as the number of branched boreholes increases, the coal seam fracture network also increase, improving the distribution of the fracture network, making the fracturing effect better. The branched boreholes appear to reduce initiation pressure and, with increasing branches, the initiation pressure decreases. A model with four tree-type, branched boreholes leads to a reduction in initiation pressure of 69%. In terms of permeability improvement technology in underground coalmines, a branched hydraulic fracturing borehole array has the advantages of reducing initiation pressure, controlling crack initiation and extension, enhancing the fracturing effect and reducing the destruction of the roof and floor.

  9. Critical review of hydraulic modeling on atmospheric heat dissipation

    International Nuclear Information System (INIS)

    Objectives of this study were: to define the useful roles of hydraulic modeling in understanding the predicting atmospheric effects of heat dissipation systems; to assess the state-of-the-art of hydraulic modeling of atmospheric phenomena; to inventory potentially useful existing hydraulic modeling facilities both in the United States and abroad; and to scope hydraulic model studies to assist the assessment of atmospheric effects of nuclear energy centers

  10. Advantages of Oscillatory Hydraulic Tomography

    Science.gov (United States)

    Kitanidis, P. K.; Bakhos, T.; Cardiff, M. A.; Barrash, W.

    2012-12-01

    Characterizing the subsurface is significant for most hydrogeologic studies, such as those involving site remediation and groundwater resource explo¬ration. A variety of hydraulic and geophysical methods have been developed to estimate hydraulic conductivity and specific storage. Hydraulic methods based on the analysis of conventional pumping tests allow the estimation of conductivity and storage without need for approximate petrophysical relations, which is an advantage over most geophysical methods that first estimate other properties and then infer values of hydraulic parameters. However, hydraulic methods have the disadvantage that the head-change signal decays with distance from the pumping well and thus becomes difficult to separate from noise except in close proximity to the source. Oscillatory hydraulic tomography (OHT) is an emerging technology to im¬age the subsurface. This method utilizes the idea of imposing sinusoidally varying pressure or discharge signals at several points, collecting head observations at several other points, and then processing these data in a tomographic fashion to estimate conductivity and storage coefficients. After an overview of the methodology, including a description of the most important potential advantages and challenges associated with this approach, two key promising features of the approach will be discussed. First, the signal at an observation point is orthogonal to and thus can be separated from nuisance inputs like head fluctuation from production wells, evapotranspiration, irrigation, and changes in the level of adjacent streams. Second, although the signal amplitude may be weak, one can extract the phase and amplitude of the os¬cillatory signal by collecting measurements over a longer time, thus compensating for the effect of large distance through longer sampling period.

  11. Hydraulic jumps in a channel

    DEFF Research Database (Denmark)

    Bonn, D.; Andersen, Anders Peter; Bohr, Tomas

    2009-01-01

    We present a study of hydraulic jumps with flow predominantly in one direction, created either by confining the flow to a narrow channel with parallel walls or by providing an inflow in the form of a narrow sheet. In the channel flow, we find a linear height profile upstream of the jump as expected...

  12. Advances of Studies on the Viral Proteins of PRRSV

    Institute of Scientific and Technical Information of China (English)

    Cao; Zongxi; Shi; Zhihai; Lin; Zhemin; Jiao; Peirong; Zhang; Guihong

    2014-01-01

    Porcine reproductive and respiratory syndrome( PRRS) is one of viral diseases with severe reproductive obstacle of pregnant sows and respiratory tract symptoms and higher mortality of piglets as characteristics,which is caused by porcine reproductive and respiratory syndrome virus( PRRSV). PRRS has brought great threats to swine industry in the world. The advances of studies on the viral proteins of PRRSV were reviewed from the genome,non-structural proteins and structural proteins of PRRSV.

  13. Validation study of thermal-hydraulic analysis program spiral for fuel pin bundle of sodium-cooled fast reactors

    International Nuclear Information System (INIS)

    Full text of publication follows: Japan Nuclear Cycle Development Institute (JNC) has been developing a numerical simulation system in order to offer methodologies to clarify thermal-hydraulic phenomena in fuel subassemblies of sodium-cooled fast reactors under various operating conditions such as normal operation, transient condition or deformed geometry condition from the viewpoint of the assessment of fuel pin structure integrity. This paper describes the validation study of SPIRAL that is one component code of the numerical simulation system and contributes to detailed simulations of local flow and temperature fields in a wire-wrapped fuel pin bundle. SPIRAL is a multi-dimensional finite element method code that can treat complicated geometries like a fuel pin bundle. For numerical stabilization, one can choose Streamline Upwind Petrov Galerkin method and Balancing Tensor Diffusivity method. Semi-implicit solution scheme (fractional step method) developed by Ramaswamy is used for time integration. As the pressure equation matrix solver, ICCG or Gaussian elimination is applied. Energy conservation equations of coolant and structure are also solved and therefore temperature distributions of both coolant and fuel pins can be calculated. Several turbulence models, high/low Reynolds number isotropic/anisotropic models, were incorporated to the code. The code was parallelized using MPI for enhancing simulation efficiency. Pre-processor is also available for numerical grid generation for wire-wrapped fuel pin bundles by curvilinear coordinate system. Fundamental validity related to solving mass, momentum and energy conservation equations and applicability of turbulence models were confirmed by simulating several basic problems. As typical examples, two kinds of simulations using high Re number models, backward facing step flow and 4- fuel-pin bundle in rectangular duct, are introduced in this paper. The simulation results indicate that RNG k-ε model shows relatively

  14. Correlation of Hydraulic Fracturing Induced Seismicity with Operation Parameters of Shale Gas Extraction: Two Case Studies in Western Canada

    Science.gov (United States)

    Farahbod, A. M.; Kao, H.; Cassidy, J. F.; Snyder, D. B.; Cairns, S.; Walker, D.

    2015-12-01

    Northeast British Columbia, specifically the Horn River Basin (HRB) and Montney Trend, are among the largest shale gas production regions in western Canada. In contrast, there has been no large-scale hydraulic fracturing (HF) operation in the Northwest Territories in the Norman Wells region of the central Mackenzie valley. In this study, we investigate the effect of injection pressure, operation duration and injected volume on the observed seismicity in the HRB and Norman Wells regions and compare our observations with the pre-HF records. In the HRB, we apply the single-station location and waveform correlation methods to establish a homogenous earthquake catalog (2006/12-2011/12). In the Northwest Territories, we combine data from a local seismograph network of 4 stations plus a dense array of 7 stations located from 1 km to 50 km from the operation wells to locate earthquakes (2013/09-2014/07). In the HRB, the initial effect of an increased injected volume is an increase in earthquake frequency but not magnitude. Local earthquakes gradually become larger in magnitude as the scale of HF in the region expands. While the injection pressure during HF operations has been regulated at a relatively constant level, the massive increase of injection volume in 2010 and 2011 coincides with a series of ML>3 events. Relatively large seismic moment release (>1014 N m) occurred only when the monthly injected volume exceeded ~150,000 m3. In addition, we observe variable time lags, from days to up to 4 months between intense HF and the occurrence of a significant local earthquake. On the other hand, in the Norman Wells region, two small-scale HF were performed in 2014 with a total injected volume of ~ 14000 m3. We observed an increase in the number of micro-earthquakes (M < 2.0) during the HF period without a clear change in the overall seismic pattern. From these two observations, we conclude that HF operations do not necessarily result in an increase in the occurrence rate of

  15. Thermally Actuated Hydraulic Pumps

    Science.gov (United States)

    Jones, Jack; Ross, Ronald; Chao, Yi

    2008-01-01

    Thermally actuated hydraulic pumps have been proposed for diverse applications in which direct electrical or mechanical actuation is undesirable and the relative slowness of thermal actuation can be tolerated. The proposed pumps would not contain any sliding (wearing) parts in their compressors and, hence, could have long operational lifetimes. The basic principle of a pump according to the proposal is to utilize the thermal expansion and contraction of a wax or other phase-change material in contact with a hydraulic fluid in a rigid chamber. Heating the chamber and its contents from below to above the melting temperature of the phase-change material would cause the material to expand significantly, thus causing a substantial increase in hydraulic pressure and/or a substantial displacement of hydraulic fluid out of the chamber. Similarly, cooling the chamber and its contents from above to below the melting temperature of the phase-change material would cause the material to contract significantly, thus causing a substantial decrease in hydraulic pressure and/or a substantial displacement of hydraulic fluid into the chamber. The displacement of the hydraulic fluid could be used to drive a piston. The figure illustrates a simple example of a hydraulic jack driven by a thermally actuated hydraulic pump. The pump chamber would be a cylinder containing encapsulated wax pellets and containing radial fins to facilitate transfer of heat to and from the wax. The plastic encapsulation would serve as an oil/wax barrier and the remaining interior space could be filled with hydraulic oil. A filter would retain the encapsulated wax particles in the pump chamber while allowing the hydraulic oil to flow into and out of the chamber. In one important class of potential applications, thermally actuated hydraulic pumps, exploiting vertical ocean temperature gradients for heating and cooling as needed, would be used to vary hydraulic pressures to control buoyancy in undersea research

  16. An economic study of an advanced technology supersonic cruise vehicle

    Science.gov (United States)

    Smith, C. L.; Williams, L. J.

    1975-01-01

    A description is given of the methods used and the results of an economic study of an advanced technology supersonic cruise vehicle. This vehicle was designed for a maximum range of 4000 n.mi. at a cruise speed of Mach 2.7 and carrying 292 passengers. The economic study includes the estimation of aircraft unit cost, operating cost, and idealized cash flow and discounted cash flow return on investment. In addition, it includes a sensitivity study on the effects of unit cost, manufacturing cost, production quantity, average trip length, fuel cost, load factor, and fare on the aircraft's economic feasibility.

  17. A scientific case study of an advanced LISA mission

    International Nuclear Information System (INIS)

    A brief status report of an ongoing scientific case study of the Advanced Laser Interferometer Antenna (ALIA) mission is presented. Key technology requirements and primary science objectives of the mission are covered in the study. Possible descope options for the mission and the corresponding compromise in science are also considered and compared. Our preliminary study indicates that ALIA holds promise in mapping out the mass and spin distribution of intermediate mass black holes possibly present in dense star clusters at low redshift as well as in shedding important light on the structure formation in the early Universe.

  18. Study of consolidation chemotherapy in advanced epithelial ovarian carcinoma

    Institute of Scientific and Technical Information of China (English)

    Cheng Ning-hai; Huang Hui-fang; Pan Lin-ya; Shen Keng; Wu Ming; Yang Jia-xin

    2007-01-01

    Objective: A prospective randomized study was designed to evaluate the role of consolidation chemotherapy in advanced epithelial ovarian carcinoma.Methods: 50 patients with advanced epithelial ovarian carcinoma treated in our hospital during the period from March 2000 to October 2005 were enrolled in this study.All patients had achieved clinical complete remission by means of standard treatments, and were randomly divided into consolidation chemotherapy group and control group.Relapse rate, and disease-free survival(DFS) time were analyzed in both groups.Results: 24 patients were assigned in consolidation chemotherapy group, and 26 patients in control group.Tumor relapse interval in consolidation group was (26.5±7.4) months, vs.(16.8±7.0) months in control group respectively, P=0.001.Time to relapse(TTR) in consolidation group was (19.2±6.8) months, vs.(10.0±6.9)months in control group, P=0.002.Analysis of DFS time and overall survival time, Log Rank test:P=0.042 and P= 0.062, respectively.Conclusions: Consolidation chemotherapy could be the relevant factor that postpones tumor relapse interval and prolongs DFS time in advanced epithelial ovarian carcinoma patients who had achived chlinical complete remission.But so far the statistic result of our clinical study is beyond the conclusion that consolidation chemotherapy can decrease relapse rate or increase survival rate.Muhicenter randomized clinical trial should be performed to confirm the role of consolidation chemotherapy in advanced epithelial ovarian carcinoma.

  19. Power management in hydraulically actuated mobile equipment

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen; Andersen, Torben Ole; Hansen, Michael Rygaard

    2008-01-01

    The focus of the current paper is on the control of hydraulic systems when utilizing the advances that electronic control may bring with regard to power management, prioritized flow sharing and anti-stall, arising from being able to control both pump, valves and engine electronically. A simple...

  20. Recent case studies and advancements in probabilistic risk assessment

    International Nuclear Information System (INIS)

    During the period from 1977 to 1984, Pickard, Lowe and Garrick, Inc., had the lead in preparing several full scope probabilistic risk assessments for electric utilities. Five of those studies are discussed from the point of view of advancements and lessons learned. The objective and trend of these studies is toward utilization of the risk models by the plant owners as risk management tools. Advancements that have been made are in presentation ad documentation of the PRAs, generation of more understandable plant level information, and improvements in methodology to facilitate technology transfer. Specific areas of advancement are in the treatment of such issues as dependent failures, human interaction, and the uncertainty in the source term. Lessons learned cover a wide spectrum and include the importance of plant specific models for meaningful risk management, the role of external events in risk, the sensitivity of contributors to choice of risk index, and the very important finding that the public risk is extremely small. The future direction of PRA is to establish less dependence on experts for in-plant application. Computerizing the PRAs such that they can be accessed on line and interactively is the key

  1. Advanced studies on the Polycapillary Optics use at XLab Frascati

    Science.gov (United States)

    Hampai, D.; Dabagov, S. B.; Cappuccio, G.

    2015-07-01

    X-ray analytical techniques are widely used in the world. By the way, due to the strong radiation-matter interaction, to design optical devices suitable for X-ray radiation remains still of wide interest. As a consequence of novel advanced material studies, in the last 30 years several typologies of X-ray lenses have been developed. In this work, a short review on the status of Polycapillary Optics (polyCO), from design and fabrication to various applications, has been presented making comparison of the results achieved by several groups through different X-ray optical elements. A focus is regarded for advanced X-ray imaging and spectroscopy tools based on combination of the modern polyCO hardware and the reconstruction software, available as homemade and commercially ones. Recent results (in three main fields, high resolution X-ray imaging, micro-XRF spectroscopy and micro-tomography) obtained at XLab Frascati have been discussed.

  2. NATO Advanced Study Institute on Low Temperature Molecular Spectroscopy

    CERN Document Server

    1996-01-01

    Molecular spectroscopy has achieved rapid and significant progress in recent years, the low temperature techniques in particular having proved very useful for the study of reactive species, phase transitions, molecular clusters and crystals, superconductors and semiconductors, biochemical systems, astrophysical problems, etc. The widening range of applications has been accompanied by significant improvements in experimental methods, and low temperature molecular spectroscopy has been revealed as the best technique, in many cases, to establish the connection between experiment and theoretical calculations. This, in turn, has led to a rapidly increasing ability to predict molecular spectroscopic properties. The combination of an advanced tutorial standpoint with an emphasis on recent advances and new perspectives in both experimental and theoretical molecular spectroscopy contained in this book offers the reader insight into a wide range of techniques, particular emphasis being given to supersonic jet and matri...

  3. System dynamics studies of advanced fuel cycle scenarios

    International Nuclear Information System (INIS)

    This work describes dynamic analysis studies of possible U.S. deployment scenarios of advanced nuclear energy systems. Different scenarios of future nuclear energy demand and different spent nuclear fuel management strategies to respond to those demands are considered. The management strategies include once-through, limited recycling, and transitional and sustained recycling strategies. The scenarios descriptions, data, timeline, and analysis are provided. Comparisons between the once-through and the recycling strategies show that the continuation of the current once-through fuel cycle practice can lead to unfavorable consequences as the demand for nuclear energy increase in the US. Those consequences include substantial increase in the number of geologic repository sites, continued accumulation of weapons-usable materials, and inefficient use of limited uranium resources. The analysis presented here shows that those concerns can only be addressed by employing an advanced fuel cycle. (author)

  4. Oluvil Port Development Project.:3rd party opinion on report by Lanka Hydraulic Institute Ltd: Oluvil Port Development Project: Studies on Beach Erosion, June 2011.

    OpenAIRE

    Frigaard, Peter; Margheritini, Lucia

    2011-01-01

    Oluvil Port Development Project is the first development of a large port infrastructure in the entire eastern coastline of Sri Lanka. The project is supported by the Danish Foreign Ministry. Feasibility studies and detailed design studies were carried out by Lanka Hydraulic Institute Ltd during the years 1995 to 2003. The design was reviewed by COWI a/s. Construction of the port was started in 2008. MT Højgaard a/s acted as contractor. The outer breakwaters were constructed as first part of t...

  5. Uncertainty in hydraulic tests in fractured rock

    International Nuclear Information System (INIS)

    Interpretation of hydraulic tests in fractured rock has uncertainty because of the different hydraulic properties of a fractured rock to a porous medium. In this study, we reviewed several interesting phenomena which show uncertainty in a hydraulic test at a fractured rock and discussed their origins and the how they should be considered during site characterisation. Our results show that the estimated hydraulic parameters of a fractured rock from a hydraulic test are associated with uncertainty due to the changed aperture and non-linear groundwater flow during the test. Although the magnitude of these two uncertainties is site-dependent, the results suggest that it is recommended to conduct a hydraulic test with a little disturbance from the natural groundwater flow to consider their uncertainty. Other effects reported from laboratory and numerical experiments such as the trapping zone effect (Boutt, 2006) and the slip condition effect (Lee, 2014) can also introduce uncertainty to a hydraulic test, which should be evaluated in a field test. It is necessary to consider the way how to evaluate the uncertainty in the hydraulic property during the site characterisation and how to apply it to the safety assessment of a subsurface repository. (authors)

  6. Modeling and Simulation of Hydraulic Engine Mounts

    Institute of Scientific and Technical Information of China (English)

    DUAN Shanzhong; Marshall McNea

    2012-01-01

    Hydraulic engine mounts are widely used in automotive powertrains for vibration isolation.A lumped mechanical parameter model is a traditional approach to model and simulate such mounts.This paper presents a dynamical model of a passive hydraulic engine mount with a double-chamber,an inertia track,a decoupler,and a plunger.The model is developed based on analogy between electrical systems and mechanical-hydraulic systems.The model is established to capture both low and high frequency dynatmic behaviors of the hydraulic mount.The model will be further used to find the approximate pulse responses of the mounts in terms of the force transmission and top chamber pressure.The close form solution from the simplifiod linear model may provide some insight into the highly nonlinear behavior of the mounts.Based on the model,computer simulation has been carried out to study dynamic performance of the hydraulic mount.

  7. INFORMATION-MEASURING TEST SYSTEM OF DIESEL LOCOMOTIVE HYDRAULIC TRANSMISSIONS

    OpenAIRE

    ZHUKOVYTSKYY I.V.; KLIUSHNYK I.A.; OCHKASOV O.B.; KORENIYK R.O.

    2015-01-01

    Purpose. The article describes the process of developing the information-measuring test system of diesel locomotives hydraulic transmission, which gives the possibility to obtain baseline data to conduct further studies for the determination of the technical condition of diesel locomotives hydraulic transmission. The improvement of factory technology of post-repair tests of hydraulic transmissions by automating the existing hydraulic transmission test stands according to the specifications of...

  8. Soil hydraulic properties of a Nitisol in Kabete, Kenya

    OpenAIRE

    Karuku, GN; Gachene, CKK; Karanja, N.; Cornelis, Wim; Verplancke, Hubert; Kironchi, G

    2012-01-01

    Water relations are among the most important physical phenomena that affect the use of soils for agricultural, ecological, environmental, and engineering purposes. To formulate soil-water relationships, soil hydraulic properties are required as essential inputs. The most important hydraulic properties are the soil-water retention curve and the hydraulic conductivity. The objective of this study was to determine the soil hydraulic properties of a Nitisol, at Kabete Campus Field Station. Use of...

  9. Thermal-hydraulics of the Loviisa reactor pressure vessel overcooling transients

    International Nuclear Information System (INIS)

    In the Loviisa reactor pressure vessel safety analyses, the thermal-hydraulics of various overcooling transients has been evaluated to give pertinent initial data for fracture-mechanics calculations. The thermal-hydraulic simulations of the developed overcooling scenarios have been performed using best-estimate thermal-hydraulic computer codes. Experimental programs have been carried out to study phenomena related to natural circulation interruptions in the reactor coolant system. These experiments include buoyancy-induced phenomena such as thermal mixing and stratification of cold high-pressure safety injection water in the cold legs and the downcomer, and oscillations of the single-phase natural circulation. In the probabilistic pressurized thermal shock study, the Loviisa training simulator and the advanced system code RELAP5/MOD2 were utilized to simulate selected sequences. Flow stagnation cases were separately calculated with the REMIX computer program. The methods employed were assessed for these calculations against the plant data and own experiments

  10. Vibration of hydraulic machinery

    CERN Document Server

    Wu, Yulin; Liu, Shuhong; Dou, Hua-Shu; Qian, Zhongdong

    2013-01-01

    Vibration of Hydraulic Machinery deals with the vibration problem which has significant influence on the safety and reliable operation of hydraulic machinery. It provides new achievements and the latest developments in these areas, even in the basic areas of this subject. The present book covers the fundamentals of mechanical vibration and rotordynamics as well as their main numerical models and analysis methods for the vibration prediction. The mechanical and hydraulic excitations to the vibration are analyzed, and the pressure fluctuations induced by the unsteady turbulent flow is predicted in order to obtain the unsteady loads. This book also discusses the loads, constraint conditions and the elastic and damping characters of the mechanical system, the structure dynamic analysis, the rotor dynamic analysis and the system instability of hydraulic machines, including the illustration of monitoring system for the instability and the vibration in hydraulic units. All the problems are necessary for vibration pr...

  11. New advances in pollination biology and the studies in China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Pollination biology is the study of the various biological features in relation to the event of pollen transfer. It is one of the central concerns of plant reproductive ecology and evolutionary biology. In this paper, we attempt to introduce the main advances and some new interests in pollination biology and make a brief review of the research work that has been done in China in recent years. We also give some insights into the study that we intend to carry out in this field in the future.

  12. Advances in molecular genetic studies of primary dystonia

    Directory of Open Access Journals (Sweden)

    MA Ling-yan

    2013-07-01

    Full Text Available Dystonias are heterogeneous hyperkinetic movement disorders characterized by involuntary muscle contractions which result in twisting, repetitive movements and abnormal postures. In recent years, there was a great advance in molecular genetic studies of primary dystonia. This paper will review the clinical characteristics and molecular genetic studies of primary dystonia, including early-onset generalized torsion dystonia (DYT1, whispering dysphonia (DYT4, dopa-responsive dystonia (DYT5, mixed-type dystonia (DYT6, paroxysmal kinesigenic dyskinesia (DYT10, myoclonus-dystonia syndrome (DYT11, rapid-onset dystonia parkinsonism (DYT12, adult-onset cervical dystonia (DYT23, craniocervical dystonia (DYT24 and primary torsion dystonia (DYT25.

  13. Wave Energy Study in China: Advancements and Perspectives

    Institute of Scientific and Technical Information of China (English)

    游亚戈; 郑永红; 沈永明; 吴必军; 刘荣

    2003-01-01

    The history and current status of research and development of wave energy in the world is briefly introduced. The main problems existing in these studies are pointed out. The description is focused on the current status and the advancements achieved in China. After analysis of the wave energy resources and practical situations in China, it is pointed out that the studies on wave energy should be not only concentrated on the conversion efficiency and costs of wave energy devices, but also focused on the technology of independent operation and stable output of electricity. Finally, the perspectives of application of wave energy in China are discussed.

  14. Experimental and Dynamic Study of the Piston Rod Lateral Friction for the Twin-Tube Hydraulic Shock Absorber

    OpenAIRE

    Yanqing Liu; Jianwu Zhang; Xiaoming Cheng

    2003-01-01

    In this paper, dynamic loads acting on a twin-tube hydraulic shock absorber are derived out both in wheel and axle planes by modeling mechanically car rear suspensions, and internal and external forces that yield lateral surface damage and wear-out of the piston rod for the absorber are analyzed according to bench and real road test measures. From viewpoint of vehicle system dynamics and experiment, such key factors as road unevenness, very high car speed and severe shock induced vibrations a...

  15. Comparison Study on Thermal-Hydraulic Analysis Depending on Liquid Relief Valve Response for an Station Blackout in CANDU-6

    International Nuclear Information System (INIS)

    The purpose of this analysis is to compare the results of thermal-hydraulic analysis depending on liquid relief valve response during a station black out (SBO) events in CANDU-6. The primary heat transport system (PHTS) behavior following the postulated SBO is analyzed using CATHENA code. In the paper, analysis was performed to evaluate the effect on coolant system where LRVs are assumed to be opened or opened according to normal open characteristics in the condition of SBO. The result showed that the primary pressure boundary is extended from LRV to DCT and the effects on primary system behavior were neglectable

  16. Comparison Study on Thermal-Hydraulic Analysis Depending on Liquid Relief Valve Response for an Station Blackout in CANDU-6

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S. M.; Kho, D. W. [KHNP-CRI, Daejeon (Korea, Republic of); Choi, S. H.; Moon, B. J.; Kim, S. R. [Nuclear Engineering Service and Solution Co., Daejeon (Korea, Republic of)

    2014-10-15

    The purpose of this analysis is to compare the results of thermal-hydraulic analysis depending on liquid relief valve response during a station black out (SBO) events in CANDU-6. The primary heat transport system (PHTS) behavior following the postulated SBO is analyzed using CATHENA code. In the paper, analysis was performed to evaluate the effect on coolant system where LRVs are assumed to be opened or opened according to normal open characteristics in the condition of SBO. The result showed that the primary pressure boundary is extended from LRV to DCT and the effects on primary system behavior were neglectable.

  17. Handbook of hydraulic fluid technology

    CERN Document Server

    Totten, George E

    2011-01-01

    ""The Handbook of Hydraulic Fluid Technology"" serves as the foremost resource for designing hydraulic systems and for selecting hydraulic fluids used in engineering applications. Featuring new illustrations, data tables, as well as practical examples, this second edition is updated with essential information on the latest hydraulic fluids and testing methods. The detailed text facilitates unparalleled understanding of the total hydraulic system, including important hardware, fluid properties, and hydraulic lubricants. Written by worldwide experts, the book also offers a rigorous overview of h

  18. Preliminary Study of Advanced Turboprops for Low Energy Consumption

    Science.gov (United States)

    Kraft, G. A.; Strack, W. C.

    1975-01-01

    The fuel savings potential of advanced turboprops (operational about 1985) was calculated and compared with that of an advanced turbofan for use in an advanced subsonic transport. At the design point, altitude 10.67 km and Mach 0.80, turbine-inlet temperature was fixed at 1590 K while overall pressure ratio was varied from 25 to 50. The regenerative turboprop had a pressure ratio of only 10 and an 85 percent effective rotary heat exchanger. Variable camber propellers were used with an efficiency of 85 percent. The study indicated a fuel savings of 33 percent, a takeoff gross weight reduction of 15 percent, and a direct operating cost reduction of 18 percent was possible when turboprops were used instead of the reference turbofan at a range of 10 200 km. These reductions were 28, 11, and 14 percent, respectively, at a range of 5500 km. Increasing overall pressure ratio from 25 to 50 saved little fuel and slightly increased takeoff gross weight.

  19. Hydraulic conductivity of rock fractures

    International Nuclear Information System (INIS)

    Yucca Mountain, Nevada contains numerous geological units that are highly fractured. A clear understanding of the hydraulic conductivity of fractures has been identified as an important scientific problem that must be addressed during the site characterization process. The problem of the flow of a single-phase fluid through a rough-walled rock fracture is discussed within the context of rigorous fluid mechanics. The derivation of the cubic law is given as the solution to the Navier-Stokes equations for flow between smooth, parallel plates, the only fracture geometry that is amenable to exact treatment. The various geometric and kinetic conditions that are necessary in order for the Navier-Stokes equations to be replaced by the more tractable lubrication or Hele-Shaw equations are studied and quantified. Various analytical and numerical results are reviewed pertaining to the problem of relating the effective hydraulic aperture to the statistics of the aperture distribution. These studies all lead to the conclusion that the effective hydraulic aperture is always less than the mean aperture, by a factor that depends on the ratio of the mean value of the aperture to its standard deviation. The tortuosity effect caused by regions where the rock walls are in contact with each other is studied using the Hele-Shaw equations, leading to a simple correction factor that depends on the area fraction occupied by the contact regions. Finally, the predicted hydraulic apertures are compared to measured values for eight data sets from the literature for which aperture and conductivity data were available on the same fracture. It is found that reasonably accurate predictions of hydraulic conductivity can be made based solely on the first two moments of the aperture distribution function, and the proportion of contact area. 68 refs

  20. Study on Detailed Calculation and Experiment Methods of Neutronics, Fuel Materials, and Thermal Hydraulics for a Commercial Type Japanese Sodium-Cooled Fast Reactor

    Directory of Open Access Journals (Sweden)

    Toshikazu Takeda

    2012-01-01

    Full Text Available This paper discusses the objectives and results of a multiyear R&D project to improve the modeling accuracy for the detailed calculation of the Japanese Sodium-cooled Fast Reactor (JSFR, although the preliminary design of JSFR is prepared using conventional methods. For detailed design calculations, new methods are required because the JSFR has special features, which cannot be accurately modeled with existing codes. An example is the presence of an inner duct in the fuel assemblies. Therefore, we have developed new calculational and experimental methods in three areas: (1 for neutronics, we discuss the development of methods and codes to model advanced FBR fuel subassemblies, (2 for fuel materials, modeling and measurement of the thermal conductivity of annular fuel is discussed, and (3 for thermal hydraulics, we describe advances in modeling and calculational models for the intermediate heat exchanger and the calculational treatment of thermal stratification in the hot plenum of an FBR under low flow conditions. The new methods are discussed and the verification tests are described. In the validation test, measured data from the prototype FBR Monju is partly used.

  1. GCFR thermal-hydraulic experiments

    International Nuclear Information System (INIS)

    The thermal-hydraulic experimental studies performed and planned for the Gas-Cooled Fast Reactor (GCFR) core assemblies are described. The experiments consist of basic studies performed to obtain correlations, and bundle experiments which provide input for code validation and design verification. These studies have been performed and are planned at European laboratories, US national laboratories, Universities in the US, and at General Atomic Company

  2. Amazon flood wave hydraulics

    Science.gov (United States)

    Trigg, Mark A.; Wilson, Matthew D.; Bates, Paul D.; Horritt, Matthew S.; Alsdorf, Douglas E.; Forsberg, Bruce R.; Vega, Maria C.

    2009-07-01

    SummaryA bathymetric survey of 575 km of the central Amazon River and one of its tributaries, the Purus, are combined with gauged data to characterise the Amazon flood wave, and for hydraulic modelling of the main channel for the period June 1995-March 1997 with the LISFLOOD-FP and HEC-RAS hydraulic models. Our investigations show that the Amazon flood wave is subcritical and diffusive in character and, due to shallow bed slopes, backwater conditions control significant reach lengths and are present for low and high water states. Comparison of the different models shows that it is necessary to include at least the diffusion term in any model, and the RMSE error in predicted water elevation at all cross sections introduced by ignoring the acceleration and advection terms is of the order of 0.02-0.03 m. The use of a wide rectangular channel approximation introduces an error of 0.10-0.15 m on the predicted water levels. Reducing the bathymetry to a simple bed slope and with mean cross section only, introduces an error in the order of 0.5 m. These results show that when compared to the mean annual amplitude of the Amazon flood wave of 11-12 m, water levels are relatively insensitive to the bathymetry of the channel model. The implication for remote sensing studies of the central Amazon channel, such as those proposed with the Surface Water and Ocean Topography mission (SWOT), is that even relatively crude assumptions regarding the channel bathymetry will be valid in order to derive discharge from water surface slope of the main channel, as long as the mean channel area is approximately correct.

  3. Hydraulic characterization of " Furcraea andina

    Science.gov (United States)

    Rivera-Velasquez, M. F.; Fallico, C.; Molinari, A.; Santillan, P.; Salazar, M.

    2012-04-01

    The present level of pollution, increasingly involving groundwaters, constitutes a serious risk for environment and human health. Therefore the remediation of saturated and unsaturated soils, removing pollutant materials through innovative and economic bio-remediation techniques is more frequently required. Recent studies on natural fiber development have shown the effectiveness of these fibers for removal of some heavy metals, due to the lignin content in the natural fibers which plays an important role in the adsorption of metal cations (Lee et al., 2004; Troisi et al., 2008; C. Fallico, 2010). In the context of remediation techniques for unsaturated and/or saturated zone, an experimental approach for the hydraulic characterization of the "Furcraea andina" (i.e., Cabuya Blanca) fiber was carried out. This fiber is native to Andean regions and grows easily in wild or cultivated form in the valleys and hillsides of Colombia, Ecuador, and Peru. Fibers of "Furcraea andina" were characterized by experimental tests to determine their hydraulic conductivity or permeability and porosity in order to use this medium for bioremediation of contaminated aquifer exploiting the physical, chemical and microbial capacity of natural fiber in heavy metal adsorption. To evaluate empirically the hydraulic conductivity, laboratory tests were carried out at constant head specifically on the fibers manually extracted. For these tests we used a flow cell (used as permeameter), containing the "Furcraea andina" fibers to be characterized, suitably connected by a tygon pipe to a Marriott's bottle, which had a plastic tube that allow the adjustment of the hydraulic head for different tests to a constant value. By this experiment it was also possible to identify relationships that enable the estimation of permeability as a function of density, i.e. of the compaction degree of the fibers. Our study was carried out for three values of hydraulic head (H), namely 10, 18, and 25 cm and for each

  4. Hydraulic study of parallel channels coupled to recirculation loops; Estudio hidraulico de canales paralelos acoplados a lazos de recirculacion

    Energy Technology Data Exchange (ETDEWEB)

    Campos G, R. M.; Cecenas F, M. [Instituto de Investigaciones Electricas, Av. Reforma 113, Col. Palmira, 62490 Cuernavaca, Morelos (Mexico)], e-mail: rmcampos@iie.org.mx

    2009-10-15

    In this work is integrated a model of recirculation loops that allows to characterize each loop for separate and with which is possible to analyze events as shot of recirculation bombs or its transfer of high to low speed. The recirculation pattern is integrated to a model of 36 channels in parallel that represents the core of a BWR. Because the core reactor is conformed by fuel assemblies physically prepared in a parallel arrangement, it is natural to obtain a parallel application of complete pattern, where are have 36 channels tasks more other two tasks that calculates recirculation and punctual kinetics, respectively. As initial test of system, which even it is found in development, was analyzed a discharge of both recirculation pumps. In this test transitory it is only verified the hydraulic behavior, the power is imposed artificially as frontier condition that is function of flow in the calculated core by the recirculation pattern. The pattern of thermal hydraulics channel and the recirculation loops are programmed in language C, the neutronic pattern is programmed in Fortran 77. For the simulations was used a work station Alpha Station DS20E with operative system Unix and the communication system Parallel Virtual Machine, that allows to a heterogeneous collection of computers in net to work like a virtual computer in parallel. (Author)

  5. Thermal-hydraulic system study of a high pressure, high temperature helium loop using RELAP5-3D code

    International Nuclear Information System (INIS)

    Highlights: ► A thermal-hydraulic system analysis for a high pressure, high temperature helium loop has been investigated. ► The loop belongs to the Helium Loop Karlsruhe (HELOKA) facility, which contains the European Helium Cooled Pebble Beds Test Blanket Module (HCPB TBM) as the test module. ► The loop including all components has been modeled using the system code REALP5-3D, and the main control strategy has been implemented as well. ► With this model, the loop dynamics in conditions relevant for blanket module operation have been demonstrated. - Abstract: The thermal-hydraulic system analysis for the Helium Loop Karlsruhe (HELOKA) facility, a high pressure, high temperature experimental helium loop having the European Helium Cooled Pebble Beds Test Blanket Module (HCPB TBM) as the test module, was investigated. Using the system code REALP5-3D, all components in the loop are modeled as well as the main control strategy. With this model, the loop dynamics in conditions relevant for blanket module operation are simulated and analyzed.

  6. Study on advanced measurement of multi-dimensional thermal hydraulics by a fast X-ray CT scanner

    International Nuclear Information System (INIS)

    A fast X-ray CT system for measurement of mixed phase flow was developed which consists of highly sensitive semiconductor detectors and a multi-pulse X-ray generator composed of electron beam source and high voltage anode ring. A scanning time of milli-second order was realized, which enables to show high performance in time resolution. After precision evaluation by acrylic plastic models, application of the CT system was performed to gas-liquid two-phase flow. It was confirmed that three-dimensional flow visualization can be made for unsteady transient and multi-dimensional phase surface distributions. Parameters of measurement can be set freely and properly according to a object. (H. Yokoo)

  7. Capacity Loss Studies on High Capacity Li-ion Cells for the Orbiter Advanced Hydraulic Power System

    Science.gov (United States)

    Jeevarajan, Judith A.; Irlbeck, Bradley W.

    2004-01-01

    Contents include the following: Introduction. Physical and electrochemical characteristics. Performance evaluation. Rate performance. Internal resistance. Performance at different temperatures. Safety evaluation. Overcharge. Overdischarge. External short. Simulated internal short. Heat-to-vent. Vibration. Drop rest. Vent and burst pressure.

  8. Drought Impacts on the Mortality of Tree Species of Different Hydraulic Adaptation Strategies Revealed in a Decade-Long Study of a Central US Temperate Forest

    Science.gov (United States)

    Gu, L.

    2014-12-01

    Although tree mortality induced by episodic drought events has been extensively reported in the literature, investigation of drought-induced tree mortality in the context of long-term plant-water relations and in the continuum of hydraulic adaptation strategies of plant species has been rare. Yet such investigation can lead to in-depth understanding of tree mortality mechanisms and predictive models. Using decade-long continuous observations of tree mortality and plant water status at the Missouri Ozark AmeriFlux (MOFLUX) site, we studied characteristics of precipitation regimes that drove drought-induced tree mortality of half a dozen of tree species with different hydraulic adaptation strategies. We found that water availability determined inter-annual variations in tree mortality with a one-year time delay. The Predawn Leaf Water Potential Integral (PLWPI) and the Mean Non-Exceedance Interval (time periods with no daily precipitation rates exceeding a threshold) with a daily threshold precipitation at 5 mm day-1 (MNEI5) of the growing season were strong predictors of the following year's mortality of species as well as plant community as a whole. The mean daily precipitation rate and the Precipitation Variability Index (PVI) individually were also good predictors of tree mortality caused by severe drought but must be used jointly to predict tree mortality caused by intermediate water stress. The PLWPI-mortality relationship was monotonic for the same species and the plant community as a whole. But it was non-monotonic across species such that species with extreme (lowest or highest) values in the continuum of PLWPI suffered higher mortality than species with intermediate values of PLWPI. This finding reconciles contradictory reports in previous studies regarding the effects of hydraulic adaptation strategies on tree mortality across species.

  9. Mirror Advanced Reactor Study (MARS) final report summary

    International Nuclear Information System (INIS)

    The Mirror Advanced Reactor Study (MARS) has resulted in an overview of a first-generation tandem mirror reactor. The central cell fusion plasma is self-sustained by alpha heating (ignition), while electron-cyclotron resonance heating and negative ion beams maintain the electrostatic confining potentials in the end plugs. Plug injection power is reduced by the use of high-field choke coils and thermal barriers, concepts to be tested in the Tandem Mirror Experiment-Upgrade (TMX-U) and Mirror Fusion Test Facility (MFTF-B) at Lawrence Livermore National Laboratory

  10. Large-eddy simulation in hydraulics

    CERN Document Server

    Rodi, Wolfgang

    2013-01-01

    Complex turbulence phenomena are of great practical importance in hydraulics, including environmental flows, and require advanced methods for their successful computation. The Large Eddy Simulation (LES), in which the larger-scale turbulent motion is directly resolved and only the small-scale motion is modelled, is particularly suited for complex situations with dominant large-scale structures and unsteadiness. Due to the increasing computer power, LES is generally used more and more in Computational Fluid Dynamics. Also in hydraulics, it offers great potential, especially for near-field probl

  11. The views of older Malaysians on advanced directive and advanced care planning: a qualitative study.

    Science.gov (United States)

    Htut, Y; Shahrul, K; Poi, P J H

    2007-01-01

    The provision of optimum care for the ageing population is dependent on the understanding of their views and values on end of life issues. A qualitative descriptive study was conducted to describe views of elderly Malaysians on Advanced Care Planning (henceforth ACP) and Advanced Directives (henceforth AD), and explore factors influencing these views. Fifteen elderly subjects with ages ranging from 65 to 83 years, representing different ethnic and religious groups in Malaysia were selected for in-depth interviews guided by a questionnaire. Five core themes were extracted from the interviews: 1) Considering the future 2) Contingency plans for future illnesses 3) Attitudes towards life prolonging treatment procedures 4) Doctor-patient relationships and 5) Influence of religion on decisions related to future illness. Despite the lack of knowledge on ACP and AD, older respondents were very receptive to their concept. Although the majority agreed on the importance of planning for future medical management and having open discussion on end of life issues with their doctor, they felt it unnecessary to make a formal written AD. Most felt that the future was best left to fate or God, and none had made any contingency plan for severe future illnesses citing religion as reason for this view. Cardiopulmonary resuscitation, mechanical ventilation and dialysis were considered by most to be invasive life prolonging treatments. We suggest that doctors initiate discussions on end of life care with every older patient and their family so as to promote awareness and introduce the concept of ACP/AD to a Malaysian setting. PMID:18330404

  12. Root hydraulic conductivity and adjustments in stomatal conductance: hydraulic strategy in response to salt stress in a halotolerant species

    Science.gov (United States)

    Vitali, Victoria; Bellati, Jorge; Soto, Gabriela; Ayub, Nicolás D.; Amodeo, Gabriela

    2015-01-01

    Recent advances at the molecular level are introducing a new scenario that needs to be integrated into the analysis of plant hydraulic properties. Although it is not yet clear to what extent this scenario alters the current proposal for the hydraulic circuit models, it introduces new insights when studying plants that are able to easily overcome water restrictions. In this context, our aim was to explore water adjustments in a halotolerant model (Beta vulgaris) by studying the coordination between the root in terms of root hydraulic conductivity (Lpr) and the shoot as reflected in the stomatal conductance (gs). The root water pathways were also analysed in terms of root suberization (apoplastic barrier) and aquaporin transcript levels (cell-to-cell pathway). Beta vulgaris showed the ability to rapidly lose (4 h) and gain (24 h) turgor when submitted to salt stress (200 mM). The reduction profile observed in Lpr and gs was consistent with a coupled process. The tuning of the root water flow involved small variations in the studied aquaporin's transcripts before anatomical modifications occurred. Exploring Lpr enhancement after halting the stress contributed to show not only a different profile in restoring Lpr but also the capacity to uncouple Lpr from gs. Beta vulgaris root plays a key role and can anticipate water loss before the aerial water status is affected. PMID:26602985

  13. A CLINICAL STUDY OF LOCALLY ADVANCED CARCINOMA OF BREAST

    Directory of Open Access Journals (Sweden)

    Mrinalini

    2015-06-01

    Full Text Available BACKGROUND : In India it is observed that most of the patients of breast cancer clinically present in late stage due to their ignorance of disease despite so much advancement in its detection and management. Locally advanced breast cancer (LABC accounts for 30 - 35% of all cases of breast cancers in India. This study aims to evaluate C linical features, Investigations, various Treatment modalities and the Clinico - pathological correlation & outcome of various treatment modalities of LABC, with special emphasis on Neo - adjuvant chemotherapy (NACT in Indian setting. MATERIAL AND METHOD : This was a non - randomised prospective observational study. We analyzed 57 patients of LABC Stage IIIB & IIIC presenting at Government Medical College, Nagpur, Maharashtra, a tertiary care C entre from September 2012 to November 2014. RESULTS : Stage IIIB comprised 84.21% patients while remaining 15.79% were having Stage IIIC disease. Skin involvement was observed in 91.23% patients. 15.79% showed supraclavicular lymph node involvement. 32 patients received NACT (2 to 6 cycles. Out of these 32, complete clinical response (cCR was 12.5%, partial response (cPR was 68.75% and pathological CR (pCR was 6.25% with Total Objective response (cCR+cPR 81.25%. Feasibility of Breast Conserving Surgery (BCS was observed in 12.5% patients. 25 patients underwent primary surgery followed by adjuvant chemotherapy. Modified Radical Mastectomy was performed in 89.48% patients. CONCLUSIONS : With overall clinical response of 81.25%, n eoadjuvant chemotherapy is the best treatment option for patients with Locally Advanced Breast Cancer with added advantage of in vivo testing the sensitivity of chemotherapeutic agents, early management of micrometastasis and down staging the primary tumour with feasibility of BCS. Patients presenting LABC constitute a diverse group for whic h a variety of treatment modalities should be instituted with co o rdinated treatment planning among surgeons

  14. Characterization of natural porous media by NMR and MRI techniques. High and low magnetic field studies for estimation of hydraulic properties

    International Nuclear Information System (INIS)

    The aim of this thesis is to apply different NMR techniques for: i) understanding the relaxometric properties of unsaturated natural porous media and ii) for a reliable quantification of water content and its spatial and temporal change in model porous media and soil cores. For that purpose, porous media with increasing complexity and heterogeneity were used (coarse and fine sand and different mixture of sand/clay) to determine the relaxation parameters in order to adapt optimal sequence and parameters for water imaging. Conventional imaging is mostly performed with superconducting high field scanners but low field scanners promise longer relaxation times and therefore smaller loss of signal from water in small and partially filled pores. By this reason high and low field NMR experiments were conducted on these porous media to characterize the dependence on the magnetic field strength. Correlations of the NMR experiments with classical soil physics method like mercury intrusion porosimetry; water retention curves (pF) and multi-step-outflow (MSO) were performed for the characterization of the hydraulic properties of the materials. Due to the extensive research the experiments have been structured in three major parts as follows. In the first part a comparison study between relaxation experiments in high and low magnetic field was performed in order to observe the influence of the magnetic field on the relaxation properties. Due to these results, in the second part of the study only low field relaxation experiments were used in the attempt of correlations with classical soil physics methods (mercury intrusion porosimetry and water retention curves) for characterizing the hydraulic behavior of the samples. Further, the aim was to combine also MRI experiments (2D and 3D NMR) with classical soil physics methods (multi-step-outflow, MSO) for the same purpose of investigating the hydraulic properties. Because low field MRI systems are still under developing for the

  15. Characterization of natural porous media by NMR and MRI techniques. High and low magnetic field studies for estimation of hydraulic properties

    Energy Technology Data Exchange (ETDEWEB)

    Stingaciu, Laura-Roxana

    2010-07-01

    The aim of this thesis is to apply different NMR techniques for: i) understanding the relaxometric properties of unsaturated natural porous media and ii) for a reliable quantification of water content and its spatial and temporal change in model porous media and soil cores. For that purpose, porous media with increasing complexity and heterogeneity were used (coarse and fine sand and different mixture of sand/clay) to determine the relaxation parameters in order to adapt optimal sequence and parameters for water imaging. Conventional imaging is mostly performed with superconducting high field scanners but low field scanners promise longer relaxation times and therefore smaller loss of signal from water in small and partially filled pores. By this reason high and low field NMR experiments were conducted on these porous media to characterize the dependence on the magnetic field strength. Correlations of the NMR experiments with classical soil physics method like mercury intrusion porosimetry; water retention curves (pF) and multi-step-outflow (MSO) were performed for the characterization of the hydraulic properties of the materials. Due to the extensive research the experiments have been structured in three major parts as follows. In the first part a comparison study between relaxation experiments in high and low magnetic field was performed in order to observe the influence of the magnetic field on the relaxation properties. Due to these results, in the second part of the study only low field relaxation experiments were used in the attempt of correlations with classical soil physics methods (mercury intrusion porosimetry and water retention curves) for characterizing the hydraulic behavior of the samples. Further, the aim was to combine also MRI experiments (2D and 3D NMR) with classical soil physics methods (multi-step-outflow, MSO) for the same purpose of investigating the hydraulic properties. Because low field MRI systems are still under developing for the

  16. Contribution to the study of thermal-hydraulic problems in nuclear reactors; Contribution a l`etude de problemes de thermohydraulique dans les reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Cognet, G

    1998-07-07

    In nuclear reactors, whatever the type considered, Pressurized Water Water Reactors (PWRs), Fast Breeder reactors (FBRs)..., thermal-hydraulics, the science of fluid mechanics and thermal behaviour, plays an essential role, both in nominal operating and accidental conditions. Fluid can either be the primary fluid (liquid or gas) or a very specific fluid called corium, which, in case of severe accident, could result from core and environning structure melting. The work reported here represents a 20-year contribution to thermal-hydraulic issues which could occur in FBRs and PWRs. Working on these two types of reactors, both in nominal and severe accident situations, has allowed me to compare the problems and to realize the importance of communication between research teams. The evolution in the complexity of studied problems, unavoidable in order to reduce costs and significantly improve safety, has led me from numerical modelling of single-phase flow turbulence to high temperature real melt experiments. The difficulties encountered in understanding the observed phenomena and in increasing experimental databases for computer code qualification have often entailed my participation in specific measurement device developments or adaptations, in particular non-intrusive devices generally based on optical techniques. Being concerned about the end-use of this research work, I actively participated in `in-situ` thermalhydraulic experiments in the FBRs: Phenix and Super-Phenix, of which I appreciated their undeniable scientific contribution. In my opinion, the thermal-hydraulic questions related to severe accidents are the most complex as they are at the cross-roads of several scientific specialities. Consequently, they require a multi-disciplinary approach and a continuous see-saw motion between experimentalists and modelling teams. After a brief description of the various problems encountered, the main ones are reported. Finally, the importance for research teams to

  17. Study on the system development for evaluating long-term alteration of hydraulic field in near field

    International Nuclear Information System (INIS)

    For the high performance evaluation of reliability of TRU waste repository, the system development for evaluating long-term alteration in consideration of the changes action of barrier materials of hydraulic field in Near Field is required. In this research, system development for evaluating long-term alteration of hydraulic field in Near Field was examined. Examination of the basic specification of chemical/dynamic alteration action analysis system used as the composition element of this system and a whole system were performed. The research result of this year is shown below. 1) The system by which the chemical changes happened by Near Field as influence of the exudation liquid from cement material are evaluated was examined. In this year, document investigation about the various processes about chemical alteration and extraction of a choice, presentation of the uncertainty about a model or data, preliminary modeling, a simple analysis tool creation and sensitivity analysis, extraction of the process which should be taken into consideration in a system valuation modeling and a phenomenon analysis model, and a corresponding mathematics model, optimization of the software composition for development of a system valuation modeling, the exercise by the preliminary system analysis model, the experiment plan for the corroboration of a model were shown. 2) In consideration of change of the physical characteristic accompanying chemical alteration of bentonite material and cement material, the system by which dynamic changes action of repository is evaluated was examined. In this year, arrangement of the dynamics action of repository for long-term were shown. Extraction of a phenomenon made applicable to evaluation was shown. And the dynamic models were investigated and the prototype of the dynamics model that can take into consideration the characteristic of bentonite material was shown. And the basic composition of a dynamic changes action analysis system was shown. 3

  18. Orbit transfer rocket engine technology program: Advanced engine study

    Science.gov (United States)

    Erickson, C. M.

    1992-01-01

    In Task D.6 of the Advanced Engine Study, three primary subtasks were accomplished: (1) design of parametric data; (2) engine requirement variation studies; and (3) vehicle study/engine study coordination. Parametric data were generated for vacuum thrusts ranging from 7500 lbf to 50,000 lbf, nozzle expansion ratios from 600 to 1200, and engine mixture ratios from 5:1 to 7:1. Failure Modes and Effects Analysis (FMEA) was used as a departure point for these parametric analyses. These data are intended to assist in definition and trade studies. In the Engine Requirements Variation Studies, the individual effects of increasing the throttling ratio from 10:1 to 20:1 and requiring the engine to operate at a maximum mixture ratio of 12:1 were determined. Off design engine balances were generated at these extreme conditions and individual component operating requirements analyzed in detail. Potential problems were identified and possible solutions generated. In the Vehicle Study/Engine Study coordination subtask, vehicle contractor support was provided as needed, addressing a variety of issues uncovered during vehicle trade studies. This support was primarily provided during Technical Interchange Meetings (TIM) in which Space Exploration Initiative (SEI) studies were addressed.

  19. Forest fire advanced system technology (FFAST) conceptual design study

    Science.gov (United States)

    Nichols, J. David; Warren, John R.

    1987-01-01

    The National Aeronautics and Space Administration's Jet Propulsion Laboratory (JPL) and the U.S. Department of Agriculture (USDA) Forest Service completed a conceptual design study that defined an integrated forest fire detection and mapping system that will be based upon technology available in the 1990s. Potential system configuration options in emerging and advanced technologies related to the conceptual design were identified and recommended for inclusion as preferred system components. System component technologies identified for an end-to-end system include airborne mounted, thermal infrared (IR) linear array detectors, automatic onboard georeferencing and signal processing, geosynchronous satellite communications links, and advanced data integration and display. Potential system configuration options were developed and examined for possible inclusion in the preferred system configuration. The preferred system configuration will provide increased performance and be cost effective over the system currently in use. Forest fire management user requirements and the system component emerging technologies were the basis for the system configuration design. The conceptual design study defined the preferred system configuration that warrants continued refinement and development, examined economic aspects of the current and preferred system, and provided preliminary cost estimates for follow-on system prototype development.

  20. Methods and advances in the study of aeroelasticity with uncertainties

    Directory of Open Access Journals (Sweden)

    Dai Yuting

    2014-06-01

    Full Text Available Uncertainties denote the operators which describe data error, numerical error and model error in the mathematical methods. The study of aeroelasticity with uncertainty embedded in the subsystems, such as the uncertainty in the modeling of structures and aerodynamics, has been a hot topic in the last decades. In this paper, advances of the analysis and design in aeroelasticity with uncertainty are summarized in detail. According to the non-probabilistic or probabilistic uncertainty, the developments of theories, methods and experiments with application to both robust and probabilistic aeroelasticity analysis are presented, respectively. In addition, the advances in aeroelastic design considering either probabilistic or non-probabilistic uncertainties are introduced along with aeroelastic analysis. This review focuses on the robust aeroelasticity study based on the structured singular value method, namely the μ method. It covers the numerical calculation algorithm of the structured singular value, uncertainty model construction, robust aeroelastic stability analysis algorithms, uncertainty level verification, and robust flutter boundary prediction in the flight test, etc. The key results and conclusions are explored. Finally, several promising problems on aeroelasticity with uncertainty are proposed for future investigation.