Verification, Validation and Uncertainty Quantification of Multi-Physics Modeling of Nuclear Reactors

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Publisher : Woodhead Publishing Series in
ISBN 13 : 9780128149546
Total Pages : 300 pages
Book Rating : 4.1/5 (495 download)

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Book Synopsis Verification, Validation and Uncertainty Quantification of Multi-Physics Modeling of Nuclear Reactors by : Maria Avramova

Download or read book Verification, Validation and Uncertainty Quantification of Multi-Physics Modeling of Nuclear Reactors written by Maria Avramova and published by Woodhead Publishing Series in. This book was released on 2018-09-15 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: Verification, Validation and Uncertainty Quantification in Multi-Physics Modeling of Nuclear Reactors is a key reference for those tasked with ensuring the credibility and reliability of engineering models and simulations for the nuclear industry and nuclear energy research. Sections discuss simulation challenges and revise key definitions, concepts and terminology. Chapters cover solution verification, the frontier discipline of multi-physics coupling verification, model validation and its applications to single and multi-scale models, and uncertainty quantification. This essential guide will greatly assist engineers, scientists, regulators and students in applying rigorous verification, validation and uncertainty quantification methodologies to the M&S tools used in the industry. The book contains a strong focus on the verification and validation procedures required for the emerging multi-physics M&S tools that have great potential for use in the licensing of new reactors, as well as for power uprating and life extensions of operating reactors. Uniquely--and crucially for nuclear engineers--demonstrates the application of verification, validation and uncertainty methodologies to the modeling and simulation (M&S) of nuclear reactors Equips the reader to develop a rigorously defensible validation process irrespective of the particular M&S tool used Brings the audience up-to-speed on validation methods for traditional M&S tools Extends the discussion to the emerging area of validation of multi-physics and multi-scale nuclear reactor simulations

Improved Best Estimate Plus Uncertainty Methodology Including Advanced Validation Concepts to License Evolving Nuclear Reactors

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (873 download)

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Book Synopsis Improved Best Estimate Plus Uncertainty Methodology Including Advanced Validation Concepts to License Evolving Nuclear Reactors by :

Download or read book Improved Best Estimate Plus Uncertainty Methodology Including Advanced Validation Concepts to License Evolving Nuclear Reactors written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Many evolving nuclear energy programs plan to use advanced predictive multi-scale multi-physics simulation and modeling capabilities to reduce cost and time from design through licensing. Historically, the role of experiments was primary tool for design and understanding of nuclear system behavior while modeling and simulation played the subordinate role of supporting experiments. In the new era of multi-scale multi-physics computational based technology development, the experiments will still be needed but they will be performed at different scales to calibrate and validate models leading predictive simulations. Cost saving goals of programs will require us to minimize the required number of validation experiments. Utilization of more multi-scale multi-physics models introduces complexities in the validation of predictive tools. Traditional methodologies will have to be modified to address these arising issues. This paper lays out the basic aspects of a methodology that can be potentially used to address these new challenges in design and licensing of evolving nuclear technology programs. The main components of the proposed methodology are verification, validation, calibration, and uncertainty quantification. An enhanced calibration concept is introduced and is accomplished through data assimilation. The goal is to enable best-estimate prediction of system behaviors in both normal and safety related environments. To achieve this goal requires the additional steps of estimating the domain of validation and quantification of uncertainties that allow for extension of results to areas of the validation domain that are not directly tested with experiments, which might include extension of the modeling and simulation (M & S) capabilities for application to full-scale systems. The new methodology suggests a formalism to quantify an adequate level of validation (predictive maturity) with respect to required selective data so that required testing can be minimized for cost saving purposes by showing further testing wold not enhance the quality of the validation of predictive tools. The proposed methodology is at a conceptual level. When matured and if considered favorably by the stakeholders, it could serve as a new framework for the next generation of the best estimate plus uncertainty licensing methodology that USNRC developed previously. In order to come to that level of maturity it is necessary to communicate the methodology to scientific, design and regulatory stakeholders for discussion and debates. This paper is the first step to establish this communication.

Model Validation and Uncertainty Quantification, Volume 3

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Publisher : Springer Science & Business Media
ISBN 13 : 3319045520
Total Pages : 419 pages
Book Rating : 4.3/5 (19 download)

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Book Synopsis Model Validation and Uncertainty Quantification, Volume 3 by : H. Sezer Atamturktur

Download or read book Model Validation and Uncertainty Quantification, Volume 3 written by H. Sezer Atamturktur and published by Springer Science & Business Media. This book was released on 2014-04-11 with total page 419 pages. Available in PDF, EPUB and Kindle. Book excerpt: This third volume of eight from the IMAC - XXXII Conference, brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Structural Dynamics, including papers on: Linear Systems Substructure Modelling Adaptive Structures Experimental Techniques Analytical Methods Damage Detection Damping of Materials & Members Modal Parameter Identification Modal Testing Methods System Identification Active Control Modal Parameter Estimation Processing Modal Data

Multi-Physics and Multi-Scale Modeling and Simulation Methods for Nuclear Reactor Application

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Publisher : Frontiers Media SA
ISBN 13 : 2832545378
Total Pages : 105 pages
Book Rating : 4.8/5 (325 download)

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Book Synopsis Multi-Physics and Multi-Scale Modeling and Simulation Methods for Nuclear Reactor Application by : Xingjie Peng

Download or read book Multi-Physics and Multi-Scale Modeling and Simulation Methods for Nuclear Reactor Application written by Xingjie Peng and published by Frontiers Media SA. This book was released on 2024-02-28 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: A nuclear reactor operates in an environment where complex multi-physics and multi-scale phenomena exist, and it requires consideration of coupling among neutronics, thermal hydraulics, fuel performance, chemical dynamics, and coupling between the reactor core and first circuit. Safe, reliable, and economical operation can be achieved by leveraging high-fidelity numerical simulation, and proper considerations for coupling among different physics and required to provide powerful numerical simulation tools. In the past simplistic models for some of the physics phenomena are used, with the recent development of advanced numerical methods, software design, and high-performance computing power, the appeal of multi-physics and multi-scale modeling and simulation has been broadened.

Uncertainty Quantification in Multiscale Materials Modeling

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Publisher : Woodhead Publishing
ISBN 13 : 008102942X
Total Pages : 606 pages
Book Rating : 4.0/5 (81 download)

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Book Synopsis Uncertainty Quantification in Multiscale Materials Modeling by : Yan Wang

Download or read book Uncertainty Quantification in Multiscale Materials Modeling written by Yan Wang and published by Woodhead Publishing. This book was released on 2020-03-10 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt: Uncertainty Quantification in Multiscale Materials Modeling provides a complete overview of uncertainty quantification (UQ) in computational materials science. It provides practical tools and methods along with examples of their application to problems in materials modeling. UQ methods are applied to various multiscale models ranging from the nanoscale to macroscale. This book presents a thorough synthesis of the state-of-the-art in UQ methods for materials modeling, including Bayesian inference, surrogate modeling, random fields, interval analysis, and sensitivity analysis, providing insight into the unique characteristics of models framed at each scale, as well as common issues in modeling across scales. Synthesizes available UQ methods for materials modeling Provides practical tools and examples for problem solving in modeling material behavior across various length scales Demonstrates UQ in density functional theory, molecular dynamics, kinetic Monte Carlo, phase field, finite element method, multiscale modeling, and to support decision making in materials design Covers quantum, atomistic, mesoscale, and engineering structure-level modeling and simulation

A Framework for Multi-physics Modeling, Design Optimization and Uncertainty Quantification of Fast Spectrum Liquid Fuel Molten Salt Reactors

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Publisher :
ISBN 13 :
Total Pages : 184 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis A Framework for Multi-physics Modeling, Design Optimization and Uncertainty Quantification of Fast Spectrum Liquid Fuel Molten Salt Reactors by : Sandesh Bhaskar

Download or read book A Framework for Multi-physics Modeling, Design Optimization and Uncertainty Quantification of Fast Spectrum Liquid Fuel Molten Salt Reactors written by Sandesh Bhaskar and published by . This book was released on 2022 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Multiscale and Multiphysics Modeling of Nuclear Facilities with Coupled Codes and its Uncertainty Quantification and Sensitivity Analysis

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Publisher : Springer Spektrum
ISBN 13 : 9783658434212
Total Pages : 0 pages
Book Rating : 4.4/5 (342 download)

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Book Synopsis Multiscale and Multiphysics Modeling of Nuclear Facilities with Coupled Codes and its Uncertainty Quantification and Sensitivity Analysis by : Chunyu Liu

Download or read book Multiscale and Multiphysics Modeling of Nuclear Facilities with Coupled Codes and its Uncertainty Quantification and Sensitivity Analysis written by Chunyu Liu and published by Springer Spektrum. This book was released on 2024-01-17 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, the author provides a deep study into multiscale and multiphysics modeling of nuclear facilities, underscoring the critical role of uncertainty quantification and sensitivity analysis to ensure the confidence in the numerical results and to identify the system characteristics. Through an in-depth study of the liquid metal cooling system from the TALL-3D loop to the SMDFR core, the research highlights the natural circulation instability, strong coupling effects, perturbation tolerance, and system stability. The culmination of the research is the formulation of an optimized uncertainty-based control scheme, demonstrating its versatility beyond the nuclear domain to other energy sectors. This groundbreaking work not only advances the comprehension and utilization of coupling schemes and uncertainty methodologies in nuclear system modeling but also adeptly bridges the theoretical constructs with tangible application, positioning itself as an indispensable resource for design, safety analysis, and advanced numerical modeling in the broader energy sector.

Model Validation and Uncertainty Quantification, Volume 3

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Publisher : Springer Nature
ISBN 13 : 3031370031
Total Pages : 208 pages
Book Rating : 4.0/5 (313 download)

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Book Synopsis Model Validation and Uncertainty Quantification, Volume 3 by : Roland Platz

Download or read book Model Validation and Uncertainty Quantification, Volume 3 written by Roland Platz and published by Springer Nature. This book was released on 2023-10-06 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: Model Validation and Uncertainty Quantification, Volume 3: Proceedings of the 41st IMAC, A Conference and Exposition on Structural Dynamics, 2023, the third volume of ten from the Conference brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Model Validation and Uncertainty Quantification, including papers on: Introduction of Uncertainty Quantification Uncertainty Quantification in Dynamics Model Form Uncertainty and Selection incl. Round Robin Challenge Sensor and Information Fusion Virtual Sensing, Certification, and Real-Time Monitoring Surrogate Modeling

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

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Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (967 download)

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Book Synopsis Validation and Calibration of Nuclear Thermal Hydraulics Multiscale Multiphysics Models - Subcooled Flow Boiling Study by :

Download or read book Validation and Calibration of Nuclear Thermal Hydraulics Multiscale Multiphysics Models - Subcooled Flow Boiling Study written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 quantitative assessment of the CASL modeling of Crud-Induced Power Shift (CIPS) phenomenon, in particular, and the CASL advanced predictive capabilities, in general. This report is prepared for the Department of Energy's Consortium for Advanced Simulation of LWRs program's VUQ Focus Area.

Reactor Physics: Methods and Applications

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Publisher : Frontiers Media SA
ISBN 13 : 2889764575
Total Pages : 272 pages
Book Rating : 4.8/5 (897 download)

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Book Synopsis Reactor Physics: Methods and Applications by : Tengfei Zhang

Download or read book Reactor Physics: Methods and Applications written by Tengfei Zhang and published by Frontiers Media SA. This book was released on 2022-06-29 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Handbook on Thermal Hydraulics in Water-Cooled Nuclear Reactors

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Publisher : Elsevier
ISBN 13 : 0323856098
Total Pages : 818 pages
Book Rating : 4.3/5 (238 download)

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Book Synopsis Handbook on Thermal Hydraulics in Water-Cooled Nuclear Reactors by : Francesco D'Auria

Download or read book Handbook on Thermal Hydraulics in Water-Cooled Nuclear Reactors written by Francesco D'Auria and published by Elsevier. This book was released on 2024-07-29 with total page 818 pages. Available in PDF, EPUB and Kindle. Book excerpt: Handbook on Thermal Hydraulics of Water-Cooled Nuclear Reactors, Volume 3, Procedures and Applications includes all new chapters which delve deeper into the topic, adding context and practical examples to help readers apply learnings to their own setting. Topics covered include experimental thermal-hydraulics and instrumentation, numerics, scaling and containment in thermal-hydraulics, as well as a title dedicated to good practices in verification and validation. This book will be a valuable reference for graduate and undergraduate students of nuclear or thermal engineering, as well as researchers in nuclear thermal-hydraulics and reactor technology, engineers working in simulation and modeling of nuclear reactors, and more. In addition, nuclear operators, code developers and safety engineers will also benefit from the practical guidance provided. Presents a comprehensive analysis on the connection between nuclear power and thermal hydraulics Includes end-of-chapter questions, quizzes and exercises to confirm understanding and provides solutions in an appendix Covers applicable nuclear reactor safety considerations and design technology throughout

Advanced Modeling and Simulation of Nuclear Reactors

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Publisher : Frontiers Media SA
ISBN 13 : 2832520316
Total Pages : 161 pages
Book Rating : 4.8/5 (325 download)

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Book Synopsis Advanced Modeling and Simulation of Nuclear Reactors by : Jingang Liang

Download or read book Advanced Modeling and Simulation of Nuclear Reactors written by Jingang Liang and published by Frontiers Media SA. This book was released on 2023-04-10 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt:

IAEA Coordinated Research Project on HTGR Reactor Physics, Thermal-hydraulics and Depletion Uncertainty Analysis

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Publisher :
ISBN 13 :
Total Pages : 68 pages
Book Rating : 4.:/5 (946 download)

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Book Synopsis IAEA Coordinated Research Project on HTGR Reactor Physics, Thermal-hydraulics and Depletion Uncertainty Analysis by :

Download or read book IAEA Coordinated Research Project on HTGR Reactor Physics, Thermal-hydraulics and Depletion Uncertainty Analysis written by and published by . This book was released on 2015 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: The continued development of High Temperature Gas Cooled Reactors (HTGRs) requires verification of HTGR design and safety features with reliable high fidelity physics models and robust, efficient, and accurate codes. The predictive capability of coupled neutronics/thermal-hydraulics and depletion simulations for reactor design and safety analysis can be assessed with sensitivity analysis (SA) and uncertainty analysis (UA) methods. Uncertainty originates from errors in physical data, manufacturing uncertainties, modelling and computational algorithms. (The interested reader is referred to the large body of published SA and UA literature for a more complete overview of the various types of uncertainties, methodologies and results obtained). SA is helpful for ranking the various sources of uncertainty and error in the results of core analyses. SA and UA are required to address cost, safety, and licensing needs and should be applied to all aspects of reactor multi-physics simulation. SA and UA can guide experimental, modelling, and algorithm research and development. Current SA and UA rely either on derivative-based methods such as stochastic sampling methods or on generalized perturbation theory to obtain sensitivity coefficients. Neither approach addresses all needs. In order to benefit from recent advances in modelling and simulation and the availability of new covariance data (nuclear data uncertainties) extensive sensitivity and uncertainty studies are needed for quantification of the impact of different sources of uncertainties on the design and safety parameters of HTGRs. Only a parallel effort in advanced simulation and in nuclear data improvement will be able to provide designers with more robust and well validated calculation tools to meet design target accuracies. In February 2009, the Technical Working Group on Gas-Cooled Reactors (TWG-GCR) of the International Atomic Energy Agency (IAEA) recommended that the proposed Coordinated Research Program (CRP) on the HTGR Uncertainty Analysis in Modelling (UAM) be implemented. This CRP is a continuation of the previous IAEA and Organization for Economic Co-operation and Development (OECD)/Nuclear Energy Agency (NEA) international activities on Verification and Validation (V & V) of available analytical capabilities for HTGR simulation for design and safety evaluations [1], [2], [3]. Within the framework of these activities different numerical and experimental benchmark problems were performed and insight was gained about specific physics phenomena and the adequacy of analysis methods.

Assessing the Reliability of Complex Models

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Publisher : National Academies Press
ISBN 13 : 0309256348
Total Pages : 144 pages
Book Rating : 4.3/5 (92 download)

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Book Synopsis Assessing the Reliability of Complex Models by : National Research Council

Download or read book Assessing the Reliability of Complex Models written by National Research Council and published by National Academies Press. This book was released on 2012-07-26 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in computing hardware and algorithms have dramatically improved the ability to simulate complex processes computationally. Today's simulation capabilities offer the prospect of addressing questions that in the past could be addressed only by resource-intensive experimentation, if at all. Assessing the Reliability of Complex Models recognizes the ubiquity of uncertainty in computational estimates of reality and the necessity for its quantification. As computational science and engineering have matured, the process of quantifying or bounding uncertainties in a computational estimate of a physical quality of interest has evolved into a small set of interdependent tasks: verification, validation, and uncertainty of quantification (VVUQ). In recognition of the increasing importance of computational simulation and the increasing need to assess uncertainties in computational results, the National Research Council was asked to study the mathematical foundations of VVUQ and to recommend steps that will ultimately lead to improved processes. Assessing the Reliability of Complex Models discusses changes in education of professionals and dissemination of information that should enhance the ability of future VVUQ practitioners to improve and properly apply VVUQ methodologies to difficult problems, enhance the ability of VVUQ customers to understand VVUQ results and use them to make informed decisions, and enhance the ability of all VVUQ stakeholders to communicate with each other. This report is an essential resource for all decision and policy makers in the field, students, stakeholders, UQ experts, and VVUQ educators and practitioners.

High Resolution Numerical Methods for Coupled Non-linear Multi-physics Simulations with Applications in Reactor Analysis

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Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (76 download)

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Book Synopsis High Resolution Numerical Methods for Coupled Non-linear Multi-physics Simulations with Applications in Reactor Analysis by : Vijay Subramaniam Mahadevan

Download or read book High Resolution Numerical Methods for Coupled Non-linear Multi-physics Simulations with Applications in Reactor Analysis written by Vijay Subramaniam Mahadevan and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The modeling of nuclear reactors involves the solution of a multi-physics problem with widely varying time and length scales. This translates mathematically to solving a system of coupled, non-linear, and stiff partial differential equations (PDEs). Multi-physics applications possess the added complexity that most of the solution fields participate in various physics components, potentially yielding spatial and/or temporal coupling errors. This dissertation deals with the verification aspects associated with such a multi-physics code, i.e., the substantiation that the mathematical description of the multi-physics equations are solved correctly (both in time and space). Conventional paradigms used in reactor analysis problems employed to couple various physics components are often non-iterative and can be inconsistent in their treatment of the non-linear terms. This leads to the usage of smaller time steps to maintain stability and accuracy requirements, thereby increasing the overall computational time for simulation. The inconsistencies of these weakly coupled solution methods can be overcome using tighter coupling strategies and yield a better approximation to the coupled non-linear operator, by resolving the dominant spatial and temporal scales involved in the multi-physics simulation. A multi-physics framework, KARMA (K(c)ode for Analysis of Reactor and other Multi-physics Applications), is presented. KARMA uses tight coupling strategies for various physical models based on a Matrix-free Nonlinear-Krylov (MFNK) framework in order to attain high-order spatio-temporal accuracy for all solution fields in amenable wall clock times, for various test problems. The framework also utilizes traditional loosely coupled methods as lower-order solvers, which serve as efficient preconditioners for the tightly coupled solution. Since the software platform employs both lower and higher-order coupling strategies, it can easily be used to test and evaluate different coupling strategies and numerical methods and to compare their efficiency for problems of interest. Multi-physics code verification efforts pertaining to reactor applications are described and associated numerical results obtained using the developed multi-physics framework are provided. The versatility of numerical methods used here for coupled problems and feasibility of general non-linear solvers with appropriate physics-based preconditioners in the KARMA framework offer significantly efficient techniques to solve multi-physics problems in reactor analysis.

Computational Fluid Dynamics and Turbulence Model Uncertainty Quantification for Nuclear Reactor Safety Applications

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Publisher :
ISBN 13 :
Total Pages : 192 pages
Book Rating : 4.:/5 (128 download)

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Book Synopsis Computational Fluid Dynamics and Turbulence Model Uncertainty Quantification for Nuclear Reactor Safety Applications by : Michael John Acton

Download or read book Computational Fluid Dynamics and Turbulence Model Uncertainty Quantification for Nuclear Reactor Safety Applications written by Michael John Acton and published by . This book was released on 2020 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational fluid dynamics (CFD) simulations are becoming an increasingly important tool across a wide range of engineering disciplines. CFD simulations improve the accuracy and predictive capability of the evaluation process through numerical solution of the Reynolds-Averaged form of the Navier-Stokes (RANS) equations describing fluid flow. Uncertainty arises in CFD simulations due to a variety of sources, and this uncertainty must be rigorously quantified in order to be useful in support of reactor licensing and decision making. In traditional system thermal hydraulics codes, the code scaling, applicability, and uncertainty (CSAU) approach is used to ensure simulation quality and to estimate the level of uncertainty present. No such method is presently available for CFD. This thesis discusses the pathway for utilizing CFD in reactor licensing applications in the face of uncertainty through the introduction of CFD-CSAU. In order to do this, modifications to the CSAU method are proposed to bring the process in line with requirements of CFD. This includes processes to ensure the quality of a simulation which are utilized in the CFD verification and validation community, but which are not currently utilized. In addition to ensuring simulation quality and confidence, a rigorous estimate of simulation uncertainty must be made. Emphasis is placed on the quantification of turbulence modeling uncertainty in a predictive context, as it is the clear missing link in the handling of CFD uncertainty. Previous work has commonly focused on the propagation of uncertainty due to turbulence model calibration coefficients, however such an approach ignores much of the uncertainty associated with the turbulence model, and does not extrapolate well to a full variety of flow conditions. In this work, a novel approach is discussed which is based on treating the uncertainty directly through the turbulent viscosity field (pt). This allows for a more complete treatment of the modeling uncertainty compared to the uncertainty in the calibration coefficients. As the turbulent viscosity takes on unique values in continuous space, the uncertainty must be modeled as a random field, defined by the marginal distribution and the covariance function. These properties are defined through two unique hyper-parameters, which are inferred on a training data set and applied to a variety of validation data sets. The approach is shown to generalize well to a wide variety of turbulent test cases in the accurate prediction of uncertainty bounds especially as compared to previous methods. The applicability for a representative reactor flow condition is demonstrated.

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

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Publisher :
ISBN 13 :
Total Pages : 347 pages
Book Rating : 4.:/5 (93 download)

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Book Synopsis Scalable Methods for Uncertainty Quantification, Data Assimilation and Target Accuracy Assessment for Multi-Physics Advanced Simulation of Light Water Reactors by : Bassam Abdullah Ayed Khuwaileh

Download or read book Scalable Methods for Uncertainty Quantification, Data Assimilation and Target Accuracy Assessment for Multi-Physics Advanced Simulation of Light Water Reactors written by Bassam Abdullah Ayed Khuwaileh and published by . This book was released on 2015 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: