微重力下低温贮箱内推进剂相变仿真模型研究

Computational Research on Phase Change Model for Cryogenic Propellant in Microgravity

低温推进剂具有沸点低、易汽化的特点,相变是低温推进剂长时间在轨蒸发量控制问题中需要考虑的首要影响因素。相变模型对低温推进剂蒸发仿真起到重要作用,构建合理的相变模型成为低温流体蒸发量仿真重要的研究方向。基于4种相变理论,采用FLUENT软件二次开发的方法,建立基于相平衡和非平衡理论的4种相变模型,开展微重力下液氢推进剂蒸发的数值模拟,并与国外探空火箭试验进行比较和验证。研究结果表明:比较4种相变模型对贮箱内压力升高速率预示的准确性,得出了适用于微重力下低温推进剂仿真的相变模型。

Boil off is a characteristic of cryogenic propellant,and the phenomenen of phase change is the major factor of cryogenic propellant storage on orbit.As the phase change model plays a key role in cryogenic fluid Computational Fluid Dynamics(CFD)simulation,the usage of reasonable phase change model will be important.Based on four different phase change theory,the commercial software FLUENT are used and four different phase change models are presented by user defined secondary developing code.A CFD research on liquid hydrogen evaporation in microgravity is present,comparing with NASA sounding rocket experiment.Finally,a reasonable phase change model is commended by comparing the pressurizing rate of the four models,which can be used in cryogenic fluid management simulation.