Welcome & Introduction Richard R. Schultz RELAP5-3D Program Manager 2007 RELAP5 International Users Seminar Idaho Falls, Idaho November 7-8, 2007
Overview • Summary of improvements in RELAP5-3D • Summary of ongoing work involving RELAP5-3D
Summary of Improvements in RELAP5-3D • Code coupling modifications (PVM improvements) • Code streamlining • Heat conduction model • 2D conduction • Alternate coupling to fluid model • Modified pump degradation model • CO2 property improvements for running near and through the critical point • Improved compressor model • SCDAP improvements—HTGR and molecular diffusion • Coupling to GAMMA code • Coding to give cross-section input to NESTLE from HELIOS
Summary of Ongoing Work Involving RELAP5-3D • Developmental assessment (DA): Paul Bayless • FORTRAN90: George Mesina • Next Generation Nuclear Plant (NGNP): Dick Schultz • GNEP: Cliff Davis • MAPLE Production Reactor • ATR Analysis • Training Workshops • MHI • Bettis • KAPL • Simulators: Three efforts are ongoing—BEST, GSE, and Western • RELAP5/GAMMA Coupled Code: Chang Oh • SNAP & RELAP5-3D: Glenn Roth • MHI • Fission surface power (Space Nuclear Fast Reactors: Scott Lucas (Dick Schultz in Scott’s absence)
Appendix K Licensing for U.S.--APWR • Customer—Mitsubishi Heavy Industries, Ltd. • Purpose—MHI intends to submit the US-APWR for licensing to the U.S. Nuclear Regulatory Commission • Work Scope: Support for Appendix K small-break LOCA licensing analyses of US-APWR using RELAP5-3D
INL Work Scope: MHI • Model changes to conform to Appendix K • Model validation & verification • Review of analysis methods and results • Methods and results documentation • Support to address NRC requests/questions
Code Modification Categories • Category 1: Required models are missing and must be added to the RELAP5-3D code. • Category 2: Requirements can be satisfied by inserting the correct input into the code for a required analysis (since the required models are already present in the code). • Category 3: Requirements can only be satisfied by performing parametric or sensitivity calculations once all the the Appendix K required models are present.
Appendix K Small-Break LOCA Models • ANS 1971 model for fission product decay. • Baker-Just model for metal-water reaction rate. • Moody model for two-phase critical flow • Appendix K models for critical heat flux • RELAP4 models for post-CHF heat transfer
Summary: MHI Work • Initial agreement for a period of 6 to 8 months with potential extension for up to 2 years. • Work consistent with INL mission and unique expertise. • Initial work scope will require about 1.3 FTEs.
Summary • RELAP5-3D has new modeling capabilities • Developmental assessment is beginning • Modernization continuing (streamlining & FORTRAN90) • Scope of applications expanding • Generation IV reactor designs • GNEP • Space nuclear reactors • Additional Appendix K efforts