Sloshing in Arbitrary Shaped Tanks

The paper describes a calculation procedure developed at Lloyd's Register of Shipping for design purposes, based on a two-dimensional numerical finite-difference method which predicts the sloshing behaviour of fluids in arbitrary shaped tanks when excited by ship motions in a seaway.The method overcomes some problems associated with model experiments. Furthermore, tank shape, internal structure and excitation can be readily modelled and the calculation provides realistic free surface behaviour and pressure time histories, including impacts. A standard excitation method is suggested which takes into account the important interactions of fluid and ship natural periods and amplitudes of ship motions.Other modes of excitation are also examined including one based on records of irregular ships' motions and another based on a numerical model of the coupled phenomenon of sloshing and ship motions.