In order to predict the pressure and investigate the
interrelation among the physical processes in cryogenic
propellant tanks, a 2D axial symmetry Volume-of-Fluid (VOF)
computational fluid dynamic (CFD) model including a liquid
propellant phase and a mixture real gas phase is established.
The propellant phase change model is based on the assumption
of thermodynamic equilibrium. Two comparisons between the
simulation results and the self-pressurization tests of two
different liquid hydrogen tanks are made to validate the model.
And the deviations of pressure in the tanks are 2.7%~6.1%. The
results indicate that the evaporation induced by the initial
overheat is the key factor of the pressure rising in the liquid
hydrogen tank at the beginning of self-pressurization, but has
less influence when the tank becomes saturated.
Papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016.