Numerical estimation on applying air-trapping mechanism to suppress sloshing loads in a prismatic tank

Abstract

The performance of the air-trapping mechanism to suppress sloshing impact pressure in a prismatic tank was numerically evaluated. In order to implement the air-trapping mechanism, a short horizontal baffle array was installed on either side of the tank to collect air by the sloshing flow. The impact pressure change was analyzed by setting the ratio of the baffle length to the tank width as a parameter, and the pressure distribution on the wall was observed through eight calculation points (CPs) set between the baffles in the direction of tank height. The suppression performance of impact pressure was evaluated using Eulerian- Eulerian multiphase model to consider the water-air two-phase flow. The visualization results show the generation of sloshing impact pressure and the effects of the air-trapping mechanism. Quantitative comparisons of time series results of pressure were performed using peak pressure comparison and fast Fourier transform (FFT) analysis. The overall sloshing impact pressure reduction was 58.2 % in the FFT analysis and the maximum reduction rate was 70.4 %.