Numerical Study of the Effect of Different Tank Shapes on Liquid Sloshing Characteristics

In nuclear power engineering, there are many tanks with irregular shapes (e.g., the cooling water tank of the containment, etc.), whose shapes are quite different from the traditional rectangular tanks. Under seismic excitation, the sloshing of the liquid in the tank produces the fluid-structure interaction (FSI) with the structure. It is crucial to study the sloshing characteristics of the water tank during the design of the reactor structure. There is a difference between the sloshing characteristics of irregularly shaped tanks and rectangular tanks, but there are few studies on this difference and the significance of the difference needs to be further investigated. To explore the aforementioned issues, based on the fluid-structure interaction theory and Housner’s equivalent mechanical model, the finite element models of the irregularly shaped water tank and the regular water tank (rectangular) are established by ANSYS software. The effect of the tank shape on the sloshing frequency and added mass of water in the tank is studied by modal analysis and calculation of the added mass. Further, the significance of the effect of tank shape on the natural and dynamic characteristics of tanks is investigated by comparing the variability of the sloshing frequency and the added mass. The results can guide the fluid-structure interaction problem in nuclear power engineering and provide a reference for the structural design of similar irregular water tanks, thus improving the safety and economy of reactor design.