Experimental and numerical studies on sloshing in a membrane-type LNG tank with two floating plates

Sloshing with two floating plates in a membrane-type liquefied natural gas (LNG) tank is experimentally studied at three different filling rates under purely harmonic roll excitation. Our primary objective is to determine the performance of the suppressing device and of corresponding mechanisms. It is concluded that the suppressing device can effectively damp the wave runup along the longitudinal bulkhead and the impact pressure acting on the bulkhead under the mild excitation amplitudes and, especially at the top of the tank. Furthermore, a numerical simulation based on a computational fluid dynamics (CFD) program is introduced to conduct an additional investigation. The accuracy of the numerical simulation is verified against experimental results by comparing the wave elevation and heave motion of two floating plates relative to the tank. The wave runup along the vertical side wall and the velocity field in the tank with floating plates are numerically evaluated and discussed as a supplement to obtain more dissipative mechanisms.