Cryogenic Sloshing Tests in a Pressurized Cylindrical Reservoir

Coupling between thermodynamic aspects and sloshing propellant is frequently of interest in cryogenic upper stages, especially during the lift-off phase and in missions including multiple restarts. Particularly in the first case, the fluid dynamic condition of the propellant is mainly influenced by various flight maneuvers. In contrast to storable propellant, cryogenic liquid sloshing evokes disturbances of the thermodynamic equilibrium between liquid and vapor. Under some circumstances, this may be critical leading to ullage collapse. The understanding of these phenomena is of major importance concerning the next generation of cryogenic upper stages. In order to investigate the coupled phenomena, benchmark tests are currently being carried out that are focused on sloshing of LN2 in a cylindrical tank. Three different setups are investigated, where the required tank pressure is established by self-pressurization, GN2 pressurization and GHe pressurization.