RBCC引射火箭燃烧室设计及试验研究 *

Design and Experimental Investigation of Ejector Rocket Chamber for RBCC Propulsion System

关键词:  火箭基组合循环  气氧/煤油  氧燃比

Key words:  RBCC  GO₂/Kerosene  Mixture ratio

摘要:

为了满足RBCC推进系统需求，进行了气氧/煤油引射火箭燃烧室的设计和试验研究。燃烧室室压为2MPa，氧燃比为1.6，火箭流量在95~285g/s范围内变化。通过火箭单独的冷、热态试验，对其流量控制、点火、喷注及面板和身部热防护进行了考核验证，均得到了较满意的结果。在此基础上研究了RBCC联试中火箭燃烧室的工作性能，试验结果表明:燃烧室的特征速度燃烧效率能达到88%~98%，且受到流量、氧燃比、动量通量比和喷注压降的影响较大，在适合的范围内选取大的动量通量比和喷注压降，能得到更好的雾化、掺混及燃烧性能；气氧/煤油的内直外旋喷嘴构型在煤油压降仅为设计点的11%时，仍能通过有效的气动作用，获得88%以上的特征速度燃烧效率；点火器的吹除气在占到火箭流量5%时，会造成燃烧室3%的性能损失，需要在试验中进行控制并在性能计算时予以考虑。在对火箭单试和联试的比较中发现，联试中由于其特征长度长燃烧更充分，火箭得到了近7%的特征速度燃烧效率增长。

Abstract:

A GO₂/kerosene ejector rocket chamber was designed and tested to meet the requirements of the RBCC propulsion system. It was required to operate at chamber pressure 2MPa and 1.6 mixture ratio，while the mass flow rate of the rocket was changed from 95g/s to 285g/s. The mass flow rate controlling，ignition，injection and thermal protection of the faceplate and chamber body have achieved reasonably good performance during the reacting flow tests and non-reacting flow tests. Then the performance of the rocket was investigated in the RBCC combined tests. As the results shown，the rocket has achieved efficiency 88%~98% C*，and it is influenced by the mass flow rate，mixture ratio，momentum flux ratio and pressure decrease of the rocket. The higher momentum flux ratio and pressure decrease in a suitable range，the better performance of the atomizing，mixing and burning will attain. Although the pressure decrease of the kerosene is only 11% of the design value，the GO₂/kerosene Gas Center Swirl Coaxial (GCSC) injector can achieve efficienicy at least 88% C* by effective aerodynamic effects. The purge flow should be controlled in tests and taken into account when the performance of the rocket is analyzed，as there will be efficiency decrease by 3% C* when the purge flow reaches 5% of the rocket mass flow rate. When the performance of the rocket is compared in the separate tests and combined tests，the rocket is found to attain almost efficiency 7% higher C* in combined test，because of its longer characteristic length.