Effect of dual vertical porous baffles on sloshing reduction in a swaying rectangular tank

Abstract

Liquid sloshing inside tanks of a vessel may result in increased/decreased vessel motions or structural damages. The resonant sloshing motions can be suppressed by using baffles inside a tank. Especially, more energy dissipation is possible by using porous baffles. Here, the effect of dual vertical porous baffles on the sloshing reduction inside a rectangular tank is investigated both theoretically and experimentally. The matched eigenfunction expansion method is applied to obtain the analytic solutions in the context of linear potential theory with porous boundary conditions. The porosity effect is included through inertial and quadratic-drag terms. The theoretical prediction is then compared with a series of experiments conducted by authors with harmonically oscillated rectangular tank at various frequencies and baffle parameters. The measured data reasonably correlate with the predicted values. It is found that the dual vertical porous baffles can significantly suppress sloshing motions when properly designed by selecting optimal porosity, submergence depth, and installation position.