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Title: Coupled full core neutron transport/CFD simulations of pressurized water reactors

Abstract

Recently as part of the CASL project, a capability to perform 3D whole-core coupled neutron transport and computational fluid dynamics (CFD) calculations was demonstrated. This work uses the 2D/1D transport code DeCART and the commercial CFD code STAR-CCM+. It builds on previous CASL work demonstrating coupling for smaller spatial domains. The coupling methodology is described along with the problem simulated and results are presented for fresh hot full power conditions. An additional comparison is made to an equivalent model that uses lower order T/H feedback to assess the importance and cost of high fidelity feedback to the neutronics problem. A simulation of a quarter core Combustion Engineering (CE) PWR core was performed with the coupled codes using a Fixed Point Gauss-Seidel iteration technique. The total approximate calculation requirements are nearly 10,000 CPU hours and 1 TB of memory. The problem took 6 coupled iterations to converge. The CFD coupled model and low order T/H feedback model compared well for global solution parameters, with a difference in the critical boron concentration and average outlet temperature of 14 ppm B and 0.94 deg. C, respectively. Differences in the power distribution were more significant with maximum relative differences in the core-wide pin peakingmore » factor (Fq) of 5.37% and average relative differences in flat flux region power of 11.54%. Future work will focus on analyzing problems more relevant to CASL using models with less approximations. (authors)« less

Authors:
; ; ;  [1]; ;  [2];  [3]
  1. Dept. of Nuclear Engineering and Radiological Sciences, Univ. of Michigan, 2200 Bonisteel Blvd, Ann Arbor, MI 48104 (United States)
  2. CD-adapco, 60 Broadhollow Road, Melville, NY 11747 (United States)
  3. Westinghouse Electric Company LLC, Columbia, SC (United States)
Publication Date:
Research Org.:
American Nuclear Society, Inc., 555 N. Kensington Avenue, La Grange Park, Illinois 60526 (United States)
OSTI Identifier:
22105708
Resource Type:
Conference
Resource Relation:
Conference: PHYSOR 2012: Conference on Advances in Reactor Physics - Linking Research, Industry, and Education, Knoxville, TN (United States), 15-20 Apr 2012; Other Information: Country of input: France; 6 refs.
Country of Publication:
United States
Language:
English
Subject:
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; APPROXIMATIONS; BORON; COMBUSTION; COMPARATIVE EVALUATIONS; COMPUTER CODES; COMPUTERIZED SIMULATION; FEEDBACK; FLUID MECHANICS; ITERATIVE METHODS; NEUTRON TRANSPORT; POWER DISTRIBUTION; PWR TYPE REACTORS

Citation Formats

Kochunas, B., Stimpson, S., Collins, B., Downar, T., Brewster, R., Baglietto, E., and Yan, J. Coupled full core neutron transport/CFD simulations of pressurized water reactors. United States: N. p., 2012. Web.
Kochunas, B., Stimpson, S., Collins, B., Downar, T., Brewster, R., Baglietto, E., & Yan, J. Coupled full core neutron transport/CFD simulations of pressurized water reactors. United States.
Kochunas, B., Stimpson, S., Collins, B., Downar, T., Brewster, R., Baglietto, E., and Yan, J. 2012. "Coupled full core neutron transport/CFD simulations of pressurized water reactors". United States. doi:.
@article{osti_22105708,
title = {Coupled full core neutron transport/CFD simulations of pressurized water reactors},
author = {Kochunas, B. and Stimpson, S. and Collins, B. and Downar, T. and Brewster, R. and Baglietto, E. and Yan, J.},
abstractNote = {Recently as part of the CASL project, a capability to perform 3D whole-core coupled neutron transport and computational fluid dynamics (CFD) calculations was demonstrated. This work uses the 2D/1D transport code DeCART and the commercial CFD code STAR-CCM+. It builds on previous CASL work demonstrating coupling for smaller spatial domains. The coupling methodology is described along with the problem simulated and results are presented for fresh hot full power conditions. An additional comparison is made to an equivalent model that uses lower order T/H feedback to assess the importance and cost of high fidelity feedback to the neutronics problem. A simulation of a quarter core Combustion Engineering (CE) PWR core was performed with the coupled codes using a Fixed Point Gauss-Seidel iteration technique. The total approximate calculation requirements are nearly 10,000 CPU hours and 1 TB of memory. The problem took 6 coupled iterations to converge. The CFD coupled model and low order T/H feedback model compared well for global solution parameters, with a difference in the critical boron concentration and average outlet temperature of 14 ppm B and 0.94 deg. C, respectively. Differences in the power distribution were more significant with maximum relative differences in the core-wide pin peaking factor (Fq) of 5.37% and average relative differences in flat flux region power of 11.54%. Future work will focus on analyzing problems more relevant to CASL using models with less approximations. (authors)},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2012,
month = 7
}

Conference:
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