多物理耦合方法在严重事故仿真软件SimSA开发中的应用

摘要

In order to expanding the scope of the full scale simulator (FSS ) to severe accident ,a simulation code was developed and named SimSA ,and the main processes of severe accident can be modeled in this code .There are three main modules in the SimSA code ,including thermal-hydraulics module (Therm) ,core behavior module (Core) and containment module (Cont ) . A multi-physical coupling method similar to SCDAP/RELAP5 was used in the integration between Therm and Core .This paper introduced the application process of the multi-physical coupling method in the development of Sim-SA ,and it was used to calculate and analyze the severe accident sequences of loss of coolant (LOCA) with failure of safety injection and station blackout (SBO) with loss of auxiliary feed water (AFW) .The calculation results of this code were compared with the calculation results of MAAP4 code .The results indicate that the application of the multi-physical coupling method in SimSA is successful .%为满足核电厂全范围模拟机对严重事故过程仿真的需求,自主开发了严重事故仿真软件SimSA,能模拟从设计基准事故到严重事故的主要事故过程,并能准确给出相关进程的计算结果.SimSA包含3大主要模块:热工水力模块(Therm)、堆芯行为模块(Core)以及安全壳行为模块(Cont).其中,Therm与Core两个模块的耦合过程中采用了SCDAP/RELAP5相似的基于过程机理的耦合方法.本文结合SimSA软件的具体情况介绍了这种耦合方法的实现过程,并采用耦合后的程序对大破口叠加安注失效及全厂断电叠加辅助给水丧失两个典型初因事故导致的严重事故序列进行了计算,将计算结果与相同初始条件下MAAP4的计算结果进行对比分析.结果表明,SimSA中采用的这种耦合方式是成功的.