液体火箭发动机尾焰对发射平台冲击效应

为研究液体火箭发动机尾焰对发射平台的冲击效应特性，建立液体火箭发动机尾焰对发射平台冲击数值计算模型.针对液氧/煤油发动机尾焰对发射平台冲击特性，基于建立模型研究了喷管出口距离平台3，5m工况下推进剂流量和复燃对冲击特性的影响，并分析了影响差异及其产生差异的原因.结果表明:尾焰自由射流区的激波膨胀、压缩距离和壁射流区面积随推进剂流量的增大而增大；考虑复燃化学反应不仅改变了自由射流区和滞止区的形状结构，而且增大了壁射流区的面积和温度；复燃和推进剂流量均是通过影响尾焰结构对冲击特性产生影响，具体影响效果与喷管出口和发射平台间距离有关. 

Impact effect of liquid rocket motor exhaust plume on launching platform

To study the impact effect of liquid rocket motor exhaust plume on launching platform, a mathematical calculation model of exhaust plume impact on launching platform for liquid rocket motor was built. For the impact effect of LOX (liquid oxygen)/ kerosene exhaust plume on the launching platform, the influences of the propellant flux and afterburning on the impact effect from the nozzle exit to the platform in two different cases of 3m and 5m were studied, the differences and the reasons for the differences were also analyzed. Results show that, with the increase of the propellant flux, the distance of shock wave expansion and compression of the free jet region and the area of the wall-jet region increased. Afterburning can not only change the structure of the free jet region and the stagnation zone, but also increase the temperature and the area of the wall-jet region. Afterburning and propellant flux influence the impact effect by generating influence on the structure of the exhaust plume, and the impact effect is related to the distance from the nozzle exit to launching platform.