压水堆核电厂稳压器波动管热分层现象数值分析

Numerical Simulation for Thermal Stratification of PWR NPP Pressurizer Surge Line

为分析评价压水堆核电厂稳压器波动管热分层现象对波动管结构完整性的影响,采用计算流体力学(CFD)分析方法,对稳压器波动管热分层现象进行了数值模拟。研究了波动管内的流体流动,得到了稳压器波动管的传热特性、流体流场和温度分布,分析了稳压器波动管波动热分层现象与波动流速之间的关系。研究结果表明:波动流速在一定范围内变化时,管道最大截面温差随着波动流速的增大而增大。并且得到了不同波动流速下管道最大截面温差及其出现的位置,指出了热分层现象发生时波动管的薄弱环节。

In order to evaluate the structural integrity of pressurizer surge line affected by thermal stratification, this paper presents the numerical simulation for thermal stratification of PWR NPP pressurizer surge line by using Computational Fliud Dynarnics（CFD） method. The flow in the surge line is studied, and the heat transfer characteristics, flow field and temperature distribution are obtained and the relationship between the phenomenon of thermal stratification and the surge velocity is analyzed. The result shows that the maximal temperature difference increases along with the increasing of surge velocity, as the surge velocity changes within certain range. The maximum temperature difference of cross section and its locations with different surge velocity are obtained, and vulnerability of the surge line when thermal stratification occurrs is pointed out.