一次火箭流量对RBCC性能影响的数值和实验研究

利用三维两相数值计算方法和地面直联试验系统,开展了不同来流速度下一次火箭流量变化对发动机性能的影响。数值研究结果表明,在不同来流条件下,一次流流量的增加对发动机推力和比冲的贡献不同,在低速条件时,一次火箭流量的增加对来流空气的加热以及缩短二次燃料的雾化蒸发时间和距离起着积极的作用,对性能的提高有一定作用;当来流速度较高时,过大一次流流量对流动通道产生了阻塞效应,造成对推力和比冲贡献作用的减小。试验结果验证了数值研究得到的规律,特别在高马赫数条件下,一次火箭流量的增加对推力和比冲的贡献是减小的,且飞行速度越高,这种贡献越小。无论低速还是高速来流条件,存在着一个优化的一次流流量,这对提高发动机性能有很大好处。

Numerical and experimental investigation on effect of primary rocket flow on performance of RBCC

Under different inflow rates,the effects of primary rocket flow on motor performance were investigated by using 3D two-phase numerical calculation method and ground direct-connect test system.The numerical results show that under different inflow conditions,the increment of primary flow has different effects on thrust and special impulse;under lower inflow rate,the increment of primary rocket flow can accelerate inflow air heating and shorten atomizing evaporation time and distance of secondary combustion,which can improve motor performance;under higher inflow rate,excessive primary rocket flow can choke flow path,which may weaken the influence of primary flow on thrust and special impulse.The experimental results validate numerical investigation law of primary flow and RBCC performance.Especially under the higher Mach number inflow condition,the effect of increment of primary flow on RBCC performance can decrease with the increase of the inflow rate.Under either lower Mach number or higher Mach number inflow condition,there exists the optimized primary flow,which can improve RBCC performance.