Studies Of Liquid Sloshing Under Random Excitations And Suppressing Effectiveness In Rectangle Tank

Sloshing is a very common fluid movement,usually occurring in a partially filled tank,such as a liquid cargo ship on a voyage.When the external excitation frequency is close to the natural frequency of the liquid in the tank or the excitation amplitude is very large,it is easy to cause the violent sway of the liquid in the tank,and then produce a strong impact pressure on the bulkhead or roof,resulting in structural damage.Sloshing has always been a hot research topic in the field of ship and Marine engineering.In this paper,based on the theory of viscous flow,the CFD software STAR-CCM+ was used to observe the evolution characteristics of free liquid surface in the whole process of sloshing through long-term numerical simulation.The sloshing of liquid tank under random excitation is studied and the effect of different baffles on suppressing sloshing is discussed.Firstly,the numerical model of two-dimensional tank is established to verify the reliability of the numerical model.Then by extending the time of numerical simulation,the free liquid level movement is studied.The whole process of swinging is divided into two stages: transient state and steady state,and the transient effect is studied.A buffer function is proposed to reduce or even eliminate the influence of transient effect.On this basis,the influence of excitation frequency and amplitude on tank sloshing is analyzed.Furthermore,the sloshing of liquid tank under immediate excitation is studied.Firstly,the influence of transient effect on random excitation is analyzed,and then the time sensitivity analysis is carried out to determine the simulation duration of random excitation.On this basis,the influence of amplitude and peak frequency of random excitation spectrum on random response is studied.Finally,the influence of baffle parameters on fluid sloshing in tank is analyzed.The influence of baffle parameters on tank natural frequency and the oscillation amplitude was analyzed.The influence of different external excitation frequencies on the steady-state amplitude of liquid in the tank is analyzed.At last,the random excitation is used to compare the response of liquid.