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RELAP-7 Progress Report. FY-2015 Optimization Activities Summary

Berry, Ray Alden·Zou, Ling·Andrs, David
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Abstract

This report summarily documents the optimization activities on RELAP-7 for FY-2015. It includes the migration from the analytical stiffened gas equation of state for both the vapor and liquid phases to accurate and efficient property evaluations for both equilibrium and metastable (nonequilibrium) states using the Spline-Based Table Look-up (SBTL) method with the IAPWS-95 properties for steam and water. It also includes the initiation of realistic closure models based, where appropriate, on the U.S. Nuclear Regulatory Commission’s TRACE code. It also describes an improved entropy viscosity numerical stabilization method for the nonequilibrium two-phase flow model of RELAP-7. For ease of presentation to the reader, the nonequilibrium two-phase flow model used in RELAP-7 is briefly presented, though for detailed explanation the reader is referred to RELAP-7 Theory Manual [R.A. Berry, J.W. Peterson, H. Zhang, R.C. Martineau, H. Zhao, L. Zou, D. Andrs, “RELAP-7 Theory Manual,” Idaho National Laboratory INL/EXT-14-31366(rev. 1), February 2014].

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21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS97 MATHEMATICS AND COMPUTINGENTROPYEntropy Viscosity MethodEQUILIBRIUMEVALUATIONNUMERICAL SOLUTIONOPTIMIZATIONPROGRESS REPORTR CODESRELAP-7 Closure RelationsRELAP-7 Equation of StateSTABILIZATIONSTEAMTWO-PHASE FLOWVISCOSITYWATER

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Berry, Ray Alden, Zou, Ling, Andrs, David. 2015-09-01. RELAP-7 Progress Report. FY-2015 Optimization Activities Summary. https://doi.org/10.2172/1244637

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