煤油在超声速气流中非定常横向喷射的实验观察

本文目的是研究煤油在超声速气流中非定常横向喷射问题，并与静止和亚声速气流中的结果进行对比。改造普通油嘴并采用单次高压燃油喷射系统，得到不同延时的流场阴影照片。结果表明：在超声速气流中，射流柱破碎是由迎风面的表面波引起的，破碎点位于表面波的波谷。雾化过程过分四个区域。射流激波由近射流柱的迎风面，并在人壁反射，非定常喷射的波系演化复杂。煤油在亚声速气流中喷射，不存在射流激波，破碎点沿射流柱上移，穿透深

Experimental Investigation on Unsteady Transverse Injection of Kerosene into a Supersonic Flow

The unsteady transverse injection of kerosene into a supersonic flow was studied experimentally in this paper. The transverse injections of kerosene into a quiescent and subsonic air inflow are also presented for a comparison. A modified fuel nozzle and a new high pressure fuel injection system were used in the experiment, and shadowgraphs were obtained for the fuel injection. In supersonic flow, results indicate that the disintegration of the jet column is caused by the surface waves induced by aerodynamic forces and the breakup point is at the wave trough. Four regimes appear clearly during the process of kerosene atomization. The jet shock wave is in three dimension and close to the windward surface of the jet column. The shock wave reflects in the duct and changes its structure with time. The results of kerosene injected into a subsonic flow are also demonstrated for comparison. In subsonic flow, the breakup point moves upwards along jet body, and depth of penetration is increased. There is no jet shock ahead of fuel jet. But the characteristics of jet breakup and atomization are similar to that in a supersonic flow. The results also show that the fuel properties have less effect on jet breakup, atomization and shock wave structure in sub and supersonic flow.