液体火箭贮箱增压过程数值模拟研究

基于流体体积函数方法建立了N2O4贮箱的二维轴对称非稳态模型，对贮箱增压过程进行了数值模拟。通过模拟结果与火箭遥测数据的对比分析证明了模型建立的合理性。模拟结果显示，贮箱内外壁面温度接近，气枕顶部温度较高。将增压消能器等效处理为I、II两种结构。对于结构I，在飞行末期整个气枕存在明显的轴向温度分层，而结构II与I相比，贮箱顶部壁面附近的温度明显低于结构I的温度，且增压气体对液面没有明显冲击作用，在设计增压消能器时宜选结构II。

Numerical Study on Tank Pressurization Process of Liquid Rocket

A two-dimensional axisymmetrical model based on volume of lfuid (VOF) method is set up to solve the unsteady process of nitrogen tetroxide(N2O4) tank. The model is used to simulate the tank pressurization process. The validity of model is tested through the comparison with the experimental data of lfight. The simulated results provided the distributions of ullage temperature and wall temperature of tank. The inner and outer wall temperature of tank is almost equal. The maximum temperature is located at the top of tank ullage. In this paper, the pressurized gas injector is equivalent to two structures of I orⅡ. For the structure ofⅠ, thermal stratiifcation of tank ullage is obvious during the lfight, and the temperature at the top of tank ullage is higher than the result of structure ofⅡ. The impact of pressurized gas to propellant liquid is negligible for the structure ofⅡ. Therefore, the structure ofⅡ is superior to the structure of I.