底排装置在压力跃变条件下的燃烧控制

为研究底排装置在压力跃变条件下的燃烧机理,实现底排燃烧控制,采用半密闭爆发器进行了模拟底部排气弹出膛口后底排药剂燃烧环境压力突然降低的试验.结果表明在压力跃变的过程中底排火焰首先熄灭;在最初130 ms内,底排装置的喷口处为超音速流动或临界流动;在点火具火焰的持续作用下,底排药剂反应表面建立起新的传热与化学反应平衡;约780 ms时底排喷口恢复稳定的燃烧与喷射.研究表明在底排喷口加装燃烧控制块能有效减缓压力跃变对底排药剂燃烧过程的影响,恢复稳定燃烧的时间显著缩短,为提高底部排气弹的纵向射程分布找到了一种新的技术途径.

Combustion Control of Base Bleed Unit at Pressure Transition

To study the combustion mechanism and combustion control of base bleed unit at pressure transition, semi-closed bomb was used to simulate the process of abrupt drop of environmental pressure when the base bleed projectile was shot. The results show that during the pressure transition the flame of base bleed charge was extinguished firstly. During the initial 130 ms, there was a supersonic stream of critical flow in the nozzle of the base bleed unit. Then with the action of the ignition device, a new balance of heat transfer and chemical reaction was built in the surface of the base bleed charge. After about 780 ms, steady combustion was resumed. Combustion control unit can effectively weaken the effect of pressure transition, and decrease the time of rebuilding steady combustion. By the research work, a new way to increase the longitudinal dispersion of base bleed projectile was found.