Abstract
A RELAP5/MOD3.2 model of a VVER-1000/MODEL V320 nuclear power plant, Balakovo Unit 4, was updated, improved and validated on the basis of an input deck prepared by the Kurchatov Institute of Moscow. The RELAP5 model includes both the primary and the secondary systems. The Emergency Core Cooling System (ECCS) is modeled according to the plant configuration. The feedwater system, along with the emergency feedwater system, is included in the model. The point reactor kinetics model, in which the decay heat is calculated with ANS decay heat data, enables the model to be used for analysis of a large spectrum of transients and accidents. The plant model is used for analysis and prediction of a cold leg Large Break Loss-of-Coolant Accident (LBLOCA). The RELAP5/MOD3.2 results showed a good agreement with calculations obtained with TECH-M computer program. The cladding temperatures of the MOX assembly have been compared with that of the hot UO₂ assembly. The peak cladding temperature of MOX assembly is about 55 K higher than that of UO₂ assembly. An uncertainty analysis has been performed for the peak cladding temperature, in which Monte Carlo calculations have been performed using the response surface built up from fifteen sets of RELAP5 calculations. The result shows that the ECCS would be sufficient to keep the cladding temperature during the scenario of a LBLOCA well below the required licensing limit.
Fu, Chun (2000). RELAP5/MOD3.2 analysis of a VVER-1000 reactor with UO[2] fuel and MOX fuel. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -2000 -THESIS -F8.