BWR STABILITY ANALYSIS WITH SIMULATE-3K

SIMULATE-3K is a two group, advanced nodal reactor analysis transient code. It has been used by many utilities for the prediction and analysis of BWR stability events. In recent years, several enhancements of the SIMULATE-3K channel and vessel thermal-hydraulic model have been made. This paper summarizes the status of the SIMULATE-3K core and vessel models. It presents results for the Ringhals-1 Stability Benchmark and for regional instability in a large BWR. Finally, modeling sensitivities to space and time discretization are discussed.