冷却剂不同流动方式对膨胀循环推力室再生冷却换热的影响

为了解液体火箭发动机膨胀循环推力室再生冷却换热特性,对某一参考发动机推力室和另外两种面积比的膨胀循环推力室建立三维计算模型,采用数值模拟的方法,考察冷却剂的温升、冷却通道压降以及推力室内壁面温度和热流密度的分布情况.重点比较了不同燃烧室圆柱段长度、冷却剂不同流动方式以及不同面积比对以上结果的影响.计算过程中采用二阶迎风格式离散控制方程.计算结果表明:采用逆流冷却时,通过加长推力室圆柱段长度使推力室受热面积增加70%后,冷却剂温升提高了一倍左右;对膨胀循环推力室进行再生冷却时,采用顺流冷却要比逆流冷却的冷却通道压降低,但同时冷却剂温升也较低,并且对喉部壁面的冷却效果较差.

Heat transfer characteristics of expander cycle thrust chamber with different cooling routing

To study the heat transfer characteristics of expander cycle regeneratively-cooled thrust chamber,three dimension computational models of a referenced thrust chamber and two expander cycle thrust chambers with different area ratio were established.The coolant heat pick-up,pressure loss in the cooling circuit,wall temperature and heat flux distribution were calculated by numerical simulation.Influence of increased length of chamber cylinder,different cooling routing and area ratio were investigated.Governing equations were discrete with two order upstream scheme.Numerical results show that when a converse cooling is taken,the area of hot gas wall surface of chamber is increased 70% by increased length of chamber cylinder and the coolant heat pick-up is increased about as much as one time;while the selected co-flow cooling routing is employed,the pressure loss is decreased in cooling circuit but the coolant heat pick-up is less than the converse cooling and this cooling routing leads higher wall temperature at the throat.