核电厂房安全壳流固耦合动力响应分析

在地震荷载作用下，核电厂房安全壳水箱内水会发生晃动，这种流固耦合作用会影响到安全壳的动力响应。采用简化附加质量法和光滑粒子流体动力学(SPH)法，分别对应不考虑和考虑水体晃动的效应，选取常用自然波Northridge波和上海人工合成波作为地震动输入，获取了7个水位工况下包括基底剪力、位移和加速度的动力响应。通过对比两种方法的模拟结果，发现考虑水体流动的SPH法要比不考虑水体晃动的简化附加质量法的动力响应要小，水箱内水的晃动对结构整体的动力响应起到了减震的作用；并分析SPH法各水位工况下的动力响应，结果表明:水位高度4.0 m时，安全壳动力响应相对较小，是水箱较为合理的储水水位。

THE DYNAMIC RESPONSE OF NPP CONTAINMENT CONSIDERING THE FLUID-STRUCTURE INTERACTION EFFECTS

The water in the containment tank of a nuclear power plant (NPP) sloshes when the structure is subjected to earthquake action. The dynamic response of the containment is affected by the fluid-structure interaction effect. The simplified additional mass method which does not consider the water sloshing and the smoothed particle hydrodynamics (SPH) method which considers the water sloshing are used to study the dynamic response of the containment of NPPs. The dynamic response including the base shear, displacement and acceleration under seven cases of various water levels is obtained when the structure is subjected to the commonly used Northridge earthquake wave and the Shanghai synthetic seismic wave. The comparison of the simulation results of the two methods shows that the dynamic response obtained by the SPH method is smaller than that by the simplified additional mass method. It indicates that the water sloshing in the tank has a damping effect on the overall dynamic response of the structure. The dynamic response at various water levels is analyzed by the SPH method. The results show that when the water level is 4.0 m, the dynamic response of the containment is relatively smaller. Therefore, 0.4 m is a reasonable water storage level of the water tank.