关键词: 液体晃荡, 多孔挡板, 冲击压力, 时域频域, 涡旋

Abstract: The liquid sloshing in the tank was excited by ship navigation in waves. The exciting forces would cause local damages to the tank structure and affect the ships motion attitude, which might effectively avoid by the porous baffles. A large-amplitude horizontal excitation test platform was constructed to discuss the response laws of impact pressure to frequency. The time domain and frequency domain characteristics of impact pressure were analyzed under the influences of porous baffles at different excitation frequencies. The reasons for the difference of impact pressure characteristics were explained from the aspect of baffle structure and vortex strength. The results show that the nonlinear characteristics such as wave overturning and breaking under large amplitude excitations will lead to the deviation of resonance frequency from natural frequency. The porous baffle may reduce the peak value and peak width of liquid sloshing impact pressure, and the reduction rate of pressure peak value is more significant at the first natural frequency. The porous baffle does not change the primary frequency component in the amplitude-frequency, and there is only a low-frequency component with low energy in the time spectrum. The solid structure of the porous baffle blocks most of the fluid movement in the traveling wave, and a small part of the remaining fluid will produce vortex movement through the pores to dissipate energy and slow down the impact of the fluid on the liquid bulkhead surfaces.

Key words: liquid sloshing, porous baffle, impact pressure, time and frequency domain, vortex