Analysis of Anderson Acceleration on a Simplified Neutronics/Thermal Hydraulics System
Abstract
ABSTRACT A standard method for solving coupled multiphysics problems in light water reactors is Picard iteration, which sequentially alternates between solving single physics applications. This solution approach is appealing due to simplicity of implementation and the ability to leverage existing software packages to accurately solve single physics applications. However, there are several drawbacks in the convergence behavior of this method; namely slow convergence and the necessity of heuristically chosen damping factors to achieve convergence in many cases. Anderson acceleration is a method that has been seen to be more robust and fast converging than Picard iteration for many problems, without significantly higher cost per iteration or complexity of implementation, though its effectiveness in the context of multiphysics coupling is not well explored. In this work, we develop a onedimensional model simulating the coupling between the neutron distribution and fuel and coolant properties in a single fuel pin. We show that this model generally captures the convergence issues noted in Picard iterations which couple highfidelity physics codes. We then use this model to gauge potential improvements with regard to rate of convergence and robustness from utilizing Anderson acceleration as an alternative to Picard iteration.
 Authors:
 North Carolina State University (NCSU), Raleigh
 ORNL
 Sandia National Laboratories (SNL)
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Consortium for Advanced Simulation of LWRs (CASL)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1265290
 DOE Contract Number:
 AC0500OR22725
 Resource Type:
 Conference
 Resource Relation:
 Conference: NS MC2015  Joint International Conference on Mathematics and Computation (M&C), Supercomputing in Nuclear Applications (SNA) and the Monte Carlo (MC) Method, Nashville, TN, USA, 20150419, 20150423
 Country of Publication:
 United States
 Language:
 English
Citation Formats
Toth, Alex, Kelley, C. T., Slattery, Stuart R, Hamilton, Steven P, Clarno, Kevin T, and Pawlowski, R. P. P. Analysis of Anderson Acceleration on a Simplified Neutronics/Thermal Hydraulics System. United States: N. p., 2015.
Web.
Toth, Alex, Kelley, C. T., Slattery, Stuart R, Hamilton, Steven P, Clarno, Kevin T, & Pawlowski, R. P. P. Analysis of Anderson Acceleration on a Simplified Neutronics/Thermal Hydraulics System. United States.
Toth, Alex, Kelley, C. T., Slattery, Stuart R, Hamilton, Steven P, Clarno, Kevin T, and Pawlowski, R. P. P. 2015.
"Analysis of Anderson Acceleration on a Simplified Neutronics/Thermal Hydraulics System". United States.
doi:.
@article{osti_1265290,
title = {Analysis of Anderson Acceleration on a Simplified Neutronics/Thermal Hydraulics System},
author = {Toth, Alex and Kelley, C. T. and Slattery, Stuart R and Hamilton, Steven P and Clarno, Kevin T and Pawlowski, R. P. P.},
abstractNote = {ABSTRACT A standard method for solving coupled multiphysics problems in light water reactors is Picard iteration, which sequentially alternates between solving single physics applications. This solution approach is appealing due to simplicity of implementation and the ability to leverage existing software packages to accurately solve single physics applications. However, there are several drawbacks in the convergence behavior of this method; namely slow convergence and the necessity of heuristically chosen damping factors to achieve convergence in many cases. Anderson acceleration is a method that has been seen to be more robust and fast converging than Picard iteration for many problems, without significantly higher cost per iteration or complexity of implementation, though its effectiveness in the context of multiphysics coupling is not well explored. In this work, we develop a onedimensional model simulating the coupling between the neutron distribution and fuel and coolant properties in a single fuel pin. We show that this model generally captures the convergence issues noted in Picard iterations which couple highfidelity physics codes. We then use this model to gauge potential improvements with regard to rate of convergence and robustness from utilizing Anderson acceleration as an alternative to Picard iteration.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2015,
month = 1
}

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