流量连续可调火箭发动机极度富燃燃烧特性

Combustion characteristics of an extreme fuel-rich throttleable rocket engine

以气氧/煤油作为推进剂对火箭发动机进行流量连续调节试验,研究火箭发动机连续变工况过程中的燃烧特性。火箭发动机通过可调气蚀文氏管连续调节煤油流量。试验在富燃工况（混合比0.405-0.690）下成功点火,并实现了混合比、燃气总流量连续调节。试验发现流量连续调节过程中,当混合比小于0.535时,燃烧室压力随煤油流量减小而增大;当混合比大于0.535时,燃烧室压力随煤油流量减小而减小。同时,特征速度和燃烧效率随混合比增大而增大,并且混合比小于0.535时特征速度、燃烧效率增大的速率大于混合比大于0.535时的速率。研究表明推进剂流量与燃烧效率同时影响燃烧室压力。当混合比小于0.535时,燃烧效率的影响占优;混合比大于0.535时,推进剂流量影响占优。

To study the combustion characteristics of a rocket engine under continuous throttling, a continuous throttling experiment was conducted by using GOX （gaseous oxygen ）/kerosene as propellants. Mass flow rate of kerosene was continuously throttled by a throttleable cavitation Venturi nozzle. Successful ignition under fuel rich condition （ mixture ratio ranged from 0. 405 to 0. 690 ） and the continuous throttling of mixture ratio and combustion gas flow rate were achieved. Results show that chamber pressure increases with the decrease of kerosene flow when the mixture ratio is less than 0. 535 but decreases when the mixture ratio is greater than 0. 535. Meanwhile, characteristic velocity and combustion efficiency increase with the increasing mixture ratio, but the increasing ratio is bigger when the mixture ratio is less than 0. 535 than that when the mixture ratio is greater than 0. 535. The results indicate that the mass flow rate of propellants and combustion efficiency simultaneously affect the chamber pressure. Combustion efficiency dominates the chamber pressure when the mixture ratio is less than 0. 535 while mass flow rate of propellants dominates when the mixture ratio is greater than 0. 535.