喷嘴型面对膏体火箭内弹道的影响

为研究燃面变化对膏体火箭发动机内弹道调节精度的影响,根据膏体火箭发动机的工作原理,分别推导了直圆管喷嘴和锥形扩张喷嘴型面下的膏体推进剂燃面方程,建立了膏体火箭发动机零维内弹道模型,分析了喷嘴型面对发动机内弹道性能的影响,并进行了直圆管喷嘴发动机试验.结果表明,直圆管喷嘴下计算的点火时间比试验结果短,但平衡时间及平衡压强与试验结果基本吻合,喷嘴型面变化对发动机平衡时间影响很大.

Influence of Nozzle Profile on Interior Ballistics of Pasty Propellant Rocket Motor

In order to study effects of burning surface variation on interior ballistics adjustment precision of pasty propellant rocket motor, burning surface functions of straight round pipe nozzle and conical expand nozzle were derived respectively based on the working principle of pasty propellant rocket motor. A 0-dimensional interior ballistics model was built. The influence of nozzle profile on interior ballistic performance of pasty propellant rocket motor was analyzed. Engine test with straight round pipe nozzle was carried out. Results show that the computed ignition time of straight round pipe nozzle is shorter than test time, but balance time and balance pressure are in agreement with test results. Nozzle profile variation affects balance time greatly.