海洋条件下小型堆堆芯补水系统模化分析

Scaling Analysis on Core Makeup System of Small Reactor under Marine Conditions

为解决海洋条件下非能动堆芯补水系统(PCMS)设计的试验验证问题,本研究以堆芯补水箱(CMT)支路为例,开展了海洋条件下PCMS热工水力现象识别,基于多级双向比例分析(H2TS)方法,对识别的关键热工水力现象进行了模化分析,获得了PCMS模化设计的相似准则。研究结果表明,PCMS内存在多种复杂热工水力现象及其耦合过程,其中CMT支路的热工水力现象最具代表性,其自然循环过程受海洋条件的影响最为显著;海洋条件导致PCMS内流体产生附加惯性力,附加加速度一致是试验模型再现海洋条件影响的必要条件。海洋条件下PCMS模化设计应遵循阻力数、Richardson数、冷凝数和加速度等相似准则,基于上述相似准则设计的试验模型能够以合理的失真水平再现设计原型内的主要热工水力现象及其耦合效应。

In order to solve the test verification problem of passive core makeup system(PCMS)design under marine conditions,this study takes the branch of core makeup tank(CMT)as an example to identify the thermal hydraulic phenomena of PCMS under marine conditions.Based on the hierarchical two-tiered scaling(H2TS)analysis method,scaling analysis is conducted for the identified key thermal hydraulic phenomena,and the similarity criteria for scaled PCMS design are obtained.The results show that there are various complex thermal hydraulic phenomena and their coupling processes in PCMS,among which the thermal hydraulic phenomena of CMT branch are the most representative,and its natural circulation process is most significantly affected by ocean conditions.The ocean conditions lead to additional inertia force on the fluid in PCMS system,and the consistent additional acceleration is a necessary condition for the experimental model to reproduce the influence of ocean conditions.The scaling design of core makeup system under ocean conditions should follow similarity criteria such as resistance number,Richardson number,condensation number and acceleration.The test model designed based on these similarity criteria can reproduce the key thermal hydraulic phenomena and their coupling effects in the prototype with reasonable distortion level.