Numerical and experimental comparisons of the self-pressurization behavior of an LH2 tank in normal gravity

In optimizing the design of cryogenic storage facilities for future in-orbit or on-surface applications the boil-off and the self-pressurization rates must be accurately predicted for different g-levels and for a variety of heat loads and distributions. In this paper, a two-phase CFD model is presented that describes the self-pressurization behavior of a flightweight partially full LH2 tank in normal gravity. Existing experimental data at different fill levels are used to assess the predictive capability of the model. The model’s predictions indicate favorable agreement with the experimentally measured pressure histories. Small deviations are observed for the median fill level cases where it is suggested that a non-uniform heat load may be the source of this discrepancy.