Calculation and position optimization on vapor cooled shield for liquid hydrogen storage

Abstract

The ZBO (zero boil off) storage of liquid hydrogen (LH2) has broad prospects in aerospace and civil market. Because of low critical temperature and volatility, LH2 tank poses severe requirements to the insulation system (multilayer insulation (MLI) is considered to be the most promising). In order to reduce heat leak into tank, vapor cooled shield (VCS) was set up to cool the MLI by retrieving the cold energy of discharged low temperature GH2. In this study, a simplified physical model is established to investigate the optimal position of VCS in MLI, and the influence of various factors on the performance of VCS has been analysed. Taking the minimum heat leak as the target, the best installation position is around 50% in MLI (inside looking outward) for the given condition. The heat leak of the tank can be reduced by 48.03% at most.