一种缩短碳氢燃料-空气混合物点火延迟的方法

采用激波风洞-激波管组合设备对预混的碳氢燃料——空气混合物的点火与超声速燃烧进行了研究。为缩短碳氢燃料-空气混合物的点火延迟时间，通过激波风洞喷管入口与接触面之间的激波反射对经过雾化与气化的碳氢燃料(汽油)进行预热；此外，由燃烧驱动激波管产生的高温燃气作为引导火焰点燃激波风洞产生的预混与预热的超声速碳氢燃料——空气混合物。采用纹影系统对超声速可燃气流中的火焰传播进行流场显示。实验结果表明，上述方法可将碳氢燃料——空气混合物的点火延迟时间缩短至小于0.2ms，同时还得出了火焰相对于超声速可燃气流的传播速度。

A method for shortening ignition delay of hydrocarbon fuel-air mixture

A combination facility,which consists of a shock tunnel and a shock tube,was used for studying ignition and supersonic combustion of premixed hydrocarbon fuel air mixture.In order to shorten the ignition delay time of hydrocarbon fuel air mixture,an atomized and vaporized hydrocarbon fuel (gasoline) was preheated by shock reflections between the entrance of nozzle and contact surface,which was located between working gas and driver gas,in the shock tunnel.In addition, a hot, burned gas generated from the shock tube was used as pilot flame for igniting the premixed and preheated supersonic hydrocarbon air mixture generated in the shock tunnel.A schlieren system was used for flow visualization of the flame propagating in a supersonic,combustible flow.By means of these methods mentioned above, the ignition delay time of the supersonic hydrocarbon air mixture can be shortened to less than 0.2 ms, and the speed of flame propagation relative to the supersonic,combustible gas was obtained.