The numerical simulation of liquid sloshing on board spacecraft

The subject of study is the influence of sloshing liquid on the dynamics of spacecraft. A combined theoretical and experimental approach has been followed. On the one hand, CFD simulations have been carried out to predict the combined liquid/solid body motion. Basically a volume-of-fluid (VOF) approach is followed, however with improvements in the treatment of the free liquid surface: these cover the surface reconstruction and displacement and the calculation of surface tension effects by means of a local height function. Also attention has been paid to the stability of the numerical coupling between solid-body dynamics and liquid dynamics. On the other hand, in-orbit experiments have been carried out with the Sloshsat FLEVO satellite. The paper describes a first comparison between theoretical predictions and experimental findings.