过载条件下固体发动机内流场数值模拟

Numerical simulation on 3-D two-phase flow field in SRM with acceleration load

关键词:  过载飞行  固体推进剂火箭发动机  三维流  二相流  数值仿真

Key words:  Overload flight  Solid propellant rocket engine  Two phase flow  Three dimensional flow  Numerical simulation

摘要:

应用颗粒轨道模型 ,连续相控制方程按二阶迎风有限体积方法进行离散 ,并对纵、横加速度载荷均为2 0g、 30g和 35g的固体火箭发动机燃烧室内两相流动进行了模拟。结果表明 ,有纵横加速度载荷的情况下 ,发动机燃烧室内颗粒相会形成粒子聚集流 ,对承载方向的装药和壁面产生严重的冲蚀 ,明显改变了发动机燃烧室内原有的轴对称流动形态 ,同时承载方向上粒子聚集流的最大密度点随横向加速度的增加而远离发动机后封头。这些结果与实验发动机试车结果有较好的一致性 ,为发动机绝热层异常烧蚀机理分析提供了理论依据

Abstract:

The 3 D two phase flow in a solid rocket motor combustion chamber with axial and lateral direction acceleration was calculated During this calculation, the particle trajectory model was applied, and 2nd order up wind limited volume methodology was employed to discretize the control equations for the continuous phase With this method, the two phase flow under the condition of 20 g , 30 g and 35 g axial and cross direction acceleration was simulated The results indicate that in such kind of circumstances, particles will impinge dramatically onto the grain and combustion chamber insulation wall in the reverse direction of acceleration action, and change the normal axisymmetry flow status in the rocket motor In addition, The high density particles flow is formed on the side wall in the reverse direction of acceleration with the phenomena that the higher is lateral direction acceleration on SRM, the far is the point of maximal density of particle flow from aft dome All these results, which are agreed well with experiment data of test motor, can provide some theoretical analysis basis for the research about abnormal ablation of insulator and abnormal combustion of grain