池式钠冷快堆热分层现象模型开发及瞬态分析

Model Development and Transient Analysis of Thermal Stratification Phenomenon in Pool-Type Sodium-Cooled Fast Reactors

针对池式钠冷快堆特点,建立了三维系统分析模型,并结合热分层现象演化机制,提出了准确模拟热分层的关键处理方法,包括能量源项处理、三维动量方程对流项处理及三维空间进口效应处理。在此基础上,采用KALIMER及MONJU热分层实验对所开发的三维系统分析模型进行验证。结果表明模型有效解决了池式钠冷快堆三维热工水力分析的难题,实现了对钠池内温度场瞬态变化及热分层现象演化进程的快速准确模拟,同时也能够确定热分层过程中池式结构表面热应力最大位置,为池式快堆安全设计提供参考。

In this paper,a three-dimensional(3D)system analysis model is established according to the characteristics of the pool-type sodium-cooled fast reactor,and combined with the evolution mechanism of thermal stratification,the key processing method of accurately simulating thermal stratification is proposed,including energy source term processing,3D momentum equation convection term processing and 3D space inlet effect processing.On this basis,the developed 3D system analysis model is verified by KALIMER and MONJU thermal stratification experiments.The results show that the model effectively solves the problem of 3D thermal hydraulic analysis of pool-type sodium-cooled fast reactor,realizes the rapid and accurate simulation of the transient change of temperature field in the sodium pool and the evolution process of thermal stratification,and can also determine the maximum position of thermal stress on the surface of pool type structure in the process of thermal stratification,which can provide a reference for the safety design of pool-type fast reactor.