Research on thermal insulation technology of aerospace cryogenic propellant tank

Abstract In this paper, the thermal insulation layer, thermal insulation support, and metal interface of the cryogenic tank are taken as the research objects, and the structural design, heat transfer mechanism analysis, heat transfer calculation model establishment, heat transfer calculation and result analysis, and temperature field numerical simulation of the cryogenic tank are studied. The heat transfer mechanism of Spray-On Foam Insulation (SOFI)/Varied Density Multi-Layer Insulation (VD-MLI) in the ground stage and space stage is analyzed. In the ground stage, SOFI heat conduction and radiation heat transfer between adjacent radiation layers in VD-MLI, gas heat conduction between adjacent radiation layers, and solid heat conduction between adjacent radiation layers were considered in terms of insulation layer design. In the space stage, SOFI heat conduction and radiation heat transfer between adjacent radiation layers in VD-MLI, residual gas heat conduction between adjacent radiation layers, and solid heat conduction between adjacent radiation layers were considered in terms of insulation layer design. Based on the heat transfer process of SOFI/VD-MLI in the ground stage and space stage, the heat transfer calculation model of SOFI/VD-MLI in the ground stage and space stage is established. According to the evaporation rate requirements of aerospace cryogenic propellant, the thermal insulation layer, thermal insulation support, and metal interface were optimized, which effectively controlled the heat flux density (HFD) and heat leakage (HL) of the cryogenic tank and ensured the evaporation rate index of cryogenic propellant and Zero Boil Off (ZBO) storage.