带装药裂纹发动机内流场数值研究

Influence of propellant crack on turbulence flow in solid rocket motor

关键词:  固体推进剂火箭发动机  固体火箭推进剂  裂纹  流动分布  数值仿真

Key words:  Soild propellant rocket engine  Solid rocket propellant  Crack  Flow distribution  Numerical simulation

摘要:

在N S方程基础上 ,考虑网格移动 ,建立了适用于固体火箭发动机内流场的湍流控制方程组 ,并对带装药裂纹的固体火箭发动机内流场进行了数值模拟 ,分析了推进剂中裂纹深度、宽度、位置、角度等多种因素对发动机内流场的影响。计算结果表明 :(1)裂纹出口处流速高 ,大于主通道流速 ,在裂纹出口附近存在回流区 ;(2 )当裂纹紧靠发动机前封头时 ,裂纹出口附近回流强度减弱 ,裂纹对发动机内的流动影响较小 ;(3 )当裂纹深度与裂纹宽度比大于 2 4 0时 ,裂纹内压强急剧升高 ,对发动机装药结构完整性具有重要影响

Abstract:

Considering grid movement, the governing equations of fluid turbulence flow was established for solid rocket motor (SRM). Numerical computations of turbulence flow with propellant crack in SRM was performed. The influence of propellant crack depth, width, position and angle on flow field in SRM was analyzed. The conclusions are as follows: (1) The velocity at crack exit is much bigger than that in SRM. There exist the vortexs at crack exit. (2) At aft dome, the vortex intensity becomes weaker. (3) As the ratio of crack depth to width is bigger than 240, the pressure in crack is high very much and the propellant structure will be destroyed.