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为了揭示低音爆进气道的特殊流动机理,设计了一种新型二元低音爆超声速进气道,其具有零度角唇罩和发散等熵压缩前体这两个典型特征,并通过仿真手段获得了其在典型状态下的流场结构和工作特性。结果表明:由于唇罩内侧倾角过大,在低来流马赫数下(Ma∞=1.8,2.0),低音爆进气道在口部产生了唇罩弯曲激波及相应的局部亚声速区,这一流动结构的存在使其在临界状态下的总压恢复系数与外压式进气道相比分别降低了2.3%和5.5%;而在高来流马赫数下(Ma∞=2.5),唇罩激波在肩部下游诱导出一个大的分离包,该分离包使得低音爆进气道的性能随下游堵塞度的变化变得敏感。由于本文设计的低音爆进气道外唇罩角为0°,其音爆水平与外压式进气道相比显著降低,其中其音爆在设计马赫数的通流状态下减小了98.6%。此外,进气道的音爆还与其工作状态相关,进气道的溢流程度越大、超声速来流的马赫数越低,音爆水平则越高。
In order to reveal the special flow mechanism of bass burst into the airway, a new type of binary bass supersonic inlet was designed, which has two typical characteristics: zero-degree angle lip and divergent isentropic compression precursors, and obtained by simulation Its typical flow field structure and operating characteristics. The results show that due to the excessive inclination angle of the lip, the brim burst shock and corresponding local subsonic velocities occur in the mouth at low flow Mach number (Ma∞ = 1.8, 2.0) The existence of a flow structure reduces the total pressure recovery coefficient in the critical state by 2.3% and 5.5%, respectively, compared with the external pressure inlet. However, at the high flow Mach number (Ma∞ = 2.5), the lip The shroud shock induces a large separation bag downstream of the shoulder that makes the performance of the bass blasting airway sensitive as the downstream clogging changes. Because the bass exploded in this paper, the outer lip angle is 0 °, the sound-explosion level is significantly lower than that of the external pressure inlet, in which the sonic burst decreases by 98.6% at the designed flow-through state of Mach number . In addition, the sonic boom of the air intake is also related to its working condition. The greater the overflow of the air intake, the lower the Mach number of the supersonic flow and the higher the sound explosion level.