Assessment of RELAP5/MOD2 critical flow model using Marviken Test Data 15 and 24

Technical Report · Wed Apr 01 00:00:00 EST 1992

OSTI ID:10150030

Kim, K; Kim, H J ^[1]

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1. Korea Inst. of Nuclear Safety, Taejon (Korea, Republic of)

The simulations of Marviken CFT 15 and 24 have been performed using RELAP5/MOD2. For the modeling of a nozzle as a pipe, the results of simulations and the CFT 15 test data are in good agreement, but the simulations underpredict by about 5 to 10% in transition region between subcooled and two-phase. In the two phase region, there happens the fluctuations of the calculated mass flowrate for the case of using the critical flow model in RELAP5/MOD3. It seems that the improvement of the critical flow model in RELAP5 during the transition period is necessary. RELAP5 critical flow model underpredicts the CFT 24 data by 10 to 20% in two phase choked flow region, while its predictions are in good agreement with subcooled choked flowrate data. The modeling of a nozzle as a pipe in the case of CFT 24 may give rise of unreasonable results in subcooled critical flow region.

• Research Organization: Nuclear Regulatory Commission, Washington, DC (United States). Office of Nuclear Regulatory Research; Korea Inst. of Nuclear Safety, Taejon (Korea, Republic of)
• Sponsoring Organization: Nuclear Regulatory Commission, Washington, DC (United States)
• OSTI ID: 10150030
• Report Number(s): NUREG/IA-0086; ON: TI92014144
• Resource Relation: Other Information: PBD: Apr 1992
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
MARVIKEN REACTOR
LOSS OF COOLANT
FLOW MODELS
NOZZLES
PIPES
FLUID FLOW
HEAT TRANSFER
HYDRAULICS
R CODES
FLOW RATE
EVALUATION
INTERNATIONAL COOPERATION
RESEARCH PROGRAMS
REACTOR SAFETY
COMPUTER PROGRAM DOCUMENTATION
220900
210400
990200
POWER REACTORS
NONBREEDING
OTHERWISE MODERATED OR UNMODERATED
MATHEMATICS AND COMPUTERS