The main content of the current study is to establish the simplified analysis for the sloshing analysis method, and to validate the reliability of the simplified equivalent mass for sloshing analysis.
Vertical and horizontal liquid storage tank have been considered in this paper, separately. The finite element software with dynamic analysis capability was used to solve the problem. In order to include the interaction problem, finite elements that incorporate the effect of liquid and the shell were used. Both the shell regions and liquid regions are modeled using finite elements. And for simplified equivalent mass model, the convective mass is lumped at the center and at a height of the tank by spring of horizontal direction and vertical direction, this mass is connected to the joints of the finite element at the same height level as the spring, and the impulsive mass is distributed to tank wall by equivalent mass method.
By modal analysis, we can get the very similar natural frequency of the fundamental convective mode and impulsive mode between fluid-structure interaction method and equivalent mass method. The maximum error is less than 5.5%.
By response spectrum analysis for test spectra and real FRS, the reaction force of fluid-structure interaction model is relatively slightly less than equivalent mass model for vertical liquid storage tank.
The impulsive mass of the equivalent mass model have been researched in different case for the horizontal liquid storage tank. By comparing the different cases, when the impulsive mass is equal to subtracting convective mass from total fluid mass, both the resonance mode by modal analysis and reaction force by spectrum analysis for test spectra and real FRS of the equivalent mass method is closer with the fluid-structure interaction method.