核岛结构PCS水箱FSI效应简化方法研究

Simplified method for simulating the FSI effect of PCS water tank in a nuclear island building

高置冷却水箱是核电厂非能动安全壳冷却系统(PCS)的重要组成部分,在进行动力分析时,必须考虑冷却水与屏蔽厂房之间的流固耦合(FSI)效应。由于FSI效应问题复杂,数值分析耗时较长,因此,在研究核岛结构动力分析时,有必要采用简化方法,在满足计算精度要求的前提下,提高计算效率。基于Housner模型,提出一种考虑液体-水箱相互作用的简化模型。采用ADINA软件分别进行水箱FSI模型和简化模型的核岛结构三向地震反应分析,分析了FSI模型和简化模型结构反应的峰值加速度、楼层反应谱和有效应力相对误差。结果表明:提出的水箱简化模型可用于高置冷却水箱核岛结构三向地震反应分析,能够很好地模拟FSI效应。

High cooling water tank is an important component of the passive containment cooling system(PCS)in a nuclear island building,and the fluid-structure interaction(FSI)between cooling water and shield building should be considered in dynamic analysis.The FSI effect is complex and it will take a long computing time in numerical analysis,a simplified method needs to be explored to improve the calculation efficiency under the condition of satisfying a certain computing accuracy.Based on the Housner model,a simplified liquid-tank interaction model was proposed,which could be used in the dynamic analysis of PCS water tank.Three-dimensional seismic response analyses on the FSI model and simplified model were done for some nuclear island building by using ADINA software.The peak accelerations,acceleration spectra of floor responses and effective stresses by the FSI model and simplified model were compared and the relative errors were analyzed.The results show that the proposed simplified liquid-tank interaction model is suitable for the dynamic analysis of nuclear island buildings with high cooling water tank under three-dimensional earthquake actions,and good results of the simulation of FSI effect can be achieved.