Comparison and Analysis on Two Kinds of Passive Residual Heat Removal System Designs Under Station Blackout Accident for Integral Small Modular Reactor

Abstract

Small Modular Reactor has gained much attention in recent years. The passive residual heat removal system (PRHRS) is designed to increase the inherent safety features of the Integral Small Modular Reactor. There are many differences on the design of PRHRS. To get a comprehensive understanding of the PRHRS design in ISMRs, two simplified simulation models of ISMRs with different PRHRS design are built by the use of thermal hydraulic system code Relap5/Mod3.2 in this paper. A blackout accident is introduced to study the different performance between two PRHRS design models. The calculation results show that both two cases can successfully remove decay heat from the core. But there are still some differences between two cases in aspects of primary and PRHRS coolant parameters. Comparisons of the results from two cases are conducted in this paper, and the differences are carefully analyzed too.