低温推进剂在轨压力控制方法及效能对比分析

Analysis of on-orbit pressure control method and effectiveness comparison of cryogenic propellants

针对液氢、液氧低温推进剂在轨贮存时长及排气量,建立了直接排气和热力排气数学模型。在0.13—0.14 MPa和0.2—0.3 MPa两种控压区间分析了40 W和100 W漏热环境下的贮箱排气量的对比分析,结果表明液氧易于实现长期无损贮存,而液氢在轨无损贮存时间相对较短,若要实现10天或更长时间的空间任务,有必要对液氢贮箱采用热力学排气技术进行压力控制,降低液氢蒸发量。对基于热力学排气技术的液氢在不同工况下的排气量进行了计算,根据液氢在轨任务时长的要求给出了合适的控压方式选择方向。

Based on the on-orbit of storage time and gas vent, the mathematical models of direct venting and thermodynamics vent system ( TVS ) were established. The venting gas amount were analyzed in the pressure range of 0. 13-0. 14 MPa and 0. 2-0. 3 MPa when the heat leak were 40 W and 100 W respectively, which shows that the liquid oxygen is much easier to be stored in cryogenic tank than normal hydrogen. The storage time of liquid hydrogen on orbit is short so that it's necessary to use TVS in hydrogen tank to control the tank pressure and decrease the venting amount of hydrogen vapor if 10 days or longer time is required in the space mission. The venting of hydrogen vapor in storage tank with TVS is calculated under different working conditions. The appropriate method of pressure control is given according to the on-orbit mission duration.