Computional fluid dynamics (CFD) study on free surface anti-roll tank and experimental validation

Abstract

The excessive motion of a ship can seriously degrade the performance of machinery and personnel. Anti-roll tanks are tanks fitted onto ships in order to improve their response to roll motion, which is typically the largest amplitude of all the degrees of freedom. In this thesis project, a numerical model based on Volume of Fluid (VOF) is introduced to simulate the liquid sloshing inside a free surface tank (FST). And this particular model is suitable for a general thermostatic incompressible sloshing problem. Through the simulation of the model, the performance of the FST is fully investigated when the tank is excited by different periods and different amplitudes. Besides, different tank filling levels are studied to find out the optimal filling level. The results are proved by the existing experimental database. Furthermore, a model platform is designed and established to give further validation to the numerical model. The comparisons between the model tests and simulations have shown good consistency. Further improvements are proposed in the end.