液氧煤油火箭发动机排放预冷数值仿真

Numerical research of LOX/RP1 rocket engine bleed precooling

针对预冷过程中输送系统和发动机流道内沸腾传热和两相流动过程,建立一维二流体模型。以某液氧煤油发动机为原型,对不同气枕压力、排放管径和空中排放时间条件下排放预冷过程进行仿真,分析进出口温度以及流量特性的变化情况,结果表明增大排放管径和排放压力均可以增强预冷效果,而空中排放预冷时达到同样预冷效果所需的推进剂量则与管径大小无关,并且预冷效果受到地面状态的影响。

One-dimensional two-fluid model was constituted to describe the boiling heat transfer phenomenon and two-phase flow in the propellant feed system and the engine during the precooling process.Based on a LOX/RP1 engine of a second stage rocket,the bleed precooling process were simulated at different tank pressures,bleed pipe diameters and bleed time in space,mass flux,entrance and exit temperatures were analyzed.The results show that larger bleed pipe diameter and high bleed pressure can enhance the precooling effect,but the amount of popellant needed to reach the same precooling level when bleeding in space is irrelevant with the bleed pipe diameter,also the precooling effect is affected by the system condition on the ground.