Numerical and experimental study on the nonlinear liquid sloshing in ellipsoidal tanks

Liquid sloshing within partially filled tanks of large liquid cargo ships has been a major concern in marine engineering. An arbitrary Lagrangian-Eulerian (ALE) finite element (FE) method is proposed to simulate three-dimension large-amplitude liquid sloshing in ellipsoidal tanks, and its effectiveness is verified by experiments. Firstly, a scheme of the fractional step algorithm for solving the Navier-Stokes (NS) equations, combining with the characteristic-based split (CBS), in the ALE framework is constructed. Then a deft and effective mesh moving and update strategy is designed for large-amplitude liquid sloshing in ellipsoidal tanks. Subsequently, computer programming and numerical simulation are carried out and the obtained results show excellent agreements with the experiments. Finally, the nonlinear phenomena for large amplitude liquid sloshing in ellipsoidal tanks under the external excitations are investigated and the multi-modal characteristics of liquid nonlinear sloshing is revealed through a combination of numerical simulations and the ground physical experiment.