A weakly compressible formulation for modelling liquid-gas sloshing

Abstract

This study presents the development and extension of free-surface modelling techniques with the purpose of improving the modelling accuracy for liquid-gas sloshing. Considering high density ratio fluids under low Mach number conditions, the implementation of a weakly compressible formulation which accounts for variations in the gas density is presented. With the aim of ensuring a computational efficient implementation of the proposed formulation, an implicit iterative GMRES solver with LU-SGS preconditioning is employed. To evaluate the weakly compressible formulation a partially filled tank subjected to lateral excitation is numerically modelled. Pressures predicted by the weakly compressible formulation are compared to that of an incompressible solver as well as results obtained experimentally. For the problem considered, it is demonstrated that the weakly compressible formulation provides an accurate approximation of the experimental results and offers a notable improvement over the incompressible solver.