固体火箭燃气射流驱动液柱过程的CFD分析

摘要

固体火箭燃气射流驱动液柱过程会产生一个复杂的非稳态多相流场,为了研究液柱对固体火箭发动机工作过程中射流流场的降温效果,并揭示燃气冲击液柱的流动演化和气水之间的相互作用,利用FLU-ENT软件中耦合了液态水汽化方程的VOF多相流计算模型对燃气与液柱之间的耦合流动及相变过程进行了数值模拟,并与无液柱情况下射流流场的计算结果进行了对比分析.计算结果表明,当有液柱平衡体时射流流场中的压力、温度、速度波动幅度均减小,减弱了射流流场中的湍流脉动强度;液柱与燃气之间的汽化以及液柱的阻碍作用减小了射流流场的轴向发展位移,尾管后的完全发展射流流场核心区域内的压力峰值降低了0.9 MPa,温度峰值降低了503 K,速度峰值降低了291 m/s,验证了实验中液柱对燃气射流流场的降温效果.%A complex unsteady multiphase flow field is produced in the process of solid rocket gas jet driven liquid column.In this work,to study the temperature-reducing effect of the liquid column on the jet flow field of the solid rocket motor and reveal the flow evolution and the interaction between gas and water,the coupling flow and phase transition process of the gas and liquid column are simulated using the VOF multiphase flow model coupled with the FLUENT software.The results are compared with the calculation results of the jet flow field where no liquid column exists.The calculation results show that the pressure,temperature and velocity fluctuation in the jet flow field decreased when the liquid column is taken as an equilibrium body.The turbulence in tensity in the jet flow field is reduced.The development of the axial displacement of the jet flow field is reduced by the vaporization of the gas and the liquid column as well as the blocking action of the liquid column.The peak pressure is reduced by 0.9 MPa,the peak temperature by 503 K and the peak velocity by 291 m/s in the core area of the jet flow field,thus verifying the temperature-reducing effect of the liquid column on the gas jet flow field.