LH2 tank pressure control by thermodynamic vent system (TVS) at zero gravity

26th International Cryogenic Engineering Conference & International Cryogenic Materials Conference 2016

材料科学;物理学

Wang, B.^1 ; Huang, Y.H.^1 ; Chen, Z.C.^1 ; Wu, J.Y.^1 ; Li, P.^2 ; Sun, P.J.^2

Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, China^1

Shanghai Institute of Aerospace System Engineering, China^2

关键词: Cycle duration;    Evaporation loss;    Liquid hydrogen tanks;    Lumped parameter modeling;    Mathematical simulations;    Pressure variations;    Propellant tank;    Thermodynamic vent systems;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/171/1/012046/pdf
DOI  :  10.1088/1757-899X/171/1/012046

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Thermodynamic vent system (TVS) is employed for pressure control of propellant tanks at zero gravity. An analytical lumped parameter model is developed to predict pressure variation in an 18.09 m3liquid hydrogen tank equipped with TVS. Mathematical simulations are carried out assuming tank is filled up to 75% volume (liquid mass equals to 945 kg) and is subjected to heat flux of 0.76 W/m2. Tank pressure controls at 165.5-172.4, 165.5-179.3 and 165.5-182.2 kPa are compared with reference to number of vent cycles, vent duration per cycle and loss of hydrogen. Analysis results indicate that the number of vent cycles significantly decreases from 62 to 21 when tank pressure control increases from 6.9 to 20.4 kPa. Also, duration of vent cycle increases from 63 to 152 and cycle duration decreases from 3920 to 3200 s. Further, the analysis result suggests that LH2evaporation loss per day decreases from 0.17 to 0.14%. Based on the results of analysis, TVS is found effective in controlling the propellant tank pressure in zero gravity.