Numerical Investigation of External Excitation Frequency Influence on Liquid Sloshing in Two-dimensional Rectangular Tank

Sloshing in a tank is relevant for liquid tank structure design, especially on the development and application of large liquid carries. When the external excitation frequency is close to the resonance frequency of the liquid in the partial tank or the excitation amplitudes is very large, the liquid inside a partially filled tank is prone to violent oscillation and then causes violent fluid impact on tank wall or ceiling with high pressure, which can cause structure damage. In this study, the numerical model of viscous liquid in a two-dimensional rectangular tank under surge excitation were build to study the influence of external excitation frequency on liquid sloshing in 2-D rectangular tank, the liquid sloshing natural frequencies of different modes were also computed. Numerical simulations were carried out based on volume of fluid (VOF) techniques with Arbitrary-Lagrangian-Eulerian. The resulting slosh heights for various external excitation frequencies and amplitudes are compared with the data available from literatures. It is observed that the numerical results are closer to that obtained experimentally. The response of the couple system is obtained by using the based on Finite element software ADINA, sloshing characteristics of viscous liquid and elastic rectangular tank under surge excitation were analyzed. The numerical model is validated against the measured data together with other available the analytical solution and numerical result for liquid sloshing under surge motion. Through the numerical simulation, the influence of different excitation amplitude, the free elevation and the impact pressure on the tank wall were computed. Finally, the influences of different external excitation frequency on the liquid sloshing in a two dimensional rectangular tank were analyzed in detail. Frequency domain analyses of the time series of free surface elevation are carried out using the Fast Fourier Transformation (FFT) technique.