核电厂非能动安全壳冷却系统储水箱的振动特性分析

Dynamic Characteristic Analysis of the Passive Containment Cooling System Water Tank of Nuclear Power Plant

PCS储水箱是AP系列核电站非能动安全壳冷却系统的重要组成部分。水体和水箱的耦合作用会影响结构的整体性能,并可能造成水箱破坏,因此有必要在考虑流固耦合前提下对储水箱进行振动分析。首先给出了研究水体晃动的理论模型,得到了储水量分别为60%、70%、80%时水箱的1阶固有频率。之后运用有限元软件ANSYS对空水箱模型及含三种不同储水量的水箱模型进行了模态分析,研究了储水量对结构振动特性的影响,并将数值仿真结果与理论计算结果进行了对比。最后,对空箱及含60%储水量的水箱模型进行了地震反应谱分析,结果显示水体由于固有频率低,在地震载荷下易被激起,在设计中必须加以考虑。

PCS tank is an important part of passive containment cooling system of AP series nuclear power plants. The dynamic characteristics of the whole tank will be changed by the fluid-structure coupling effect, even worse it may be destroyed by the effect. Hence, it is necessary to take the fluid-structure interaction into consideration when addressing the dynamic analysis of the PCS tank. A theoretical method about the water sloshing analysis has been showed in the paper, and the first natural frequency of the tank with 60%, 70%, 80% water have been got. Then the modal analysis is preceded for the empty tank model and three different water storage models by using the finite element software ANSYS, At the same time, the influence analysis of water storage is processed. The result of the modal analysis have been compared with the result of theoretical method. Finally, the seismic response spectrum analysis have been processed. The results showed that the fluid can be excited easily by seismic load due to the lower frequency. So the sloshing effect of the water must be considered in the design of the PCS tank.