煤油超音速燃烧的试验研究

Experimental Study of Supersonic Combustion of Kerosene

在地面直连式试车台上,研究了煤油碳氢燃料超燃冲压发动机的点火燃烧性能。通过测量模型发动机壁面压力分布,比较了不同工况下的煤油点火燃烧性能。试验结果表明,在当量比为0.27～1.46的大范围内,煤油在超燃冲压模型发动机中能够成功点火,支板和凹腔对煤油在超声速气流中的点火及稳定燃烧有重要作用,少量氢气的喷入对煤油的点火燃烧有良好的促进作用。太厚的支板、过高的当量比、模型发动机第一级燃烧室加入燃料过多会使发动机壅塞,影响隔离段的正常工作,进而影响加热器喷管工作。

Research on the ignition and combustion performance of kerosene in a direct-connected scramjet model was conducted. Successful ignition and sustain combustion were achieved in the supersonic combustor. The distribution of wall pressure was measured to validate the combustion performances under different conditions. The test results indicate that kerosene fuel can be self-ignited when the equivalent fuel-air ratio varies from 0.27 to 1.46. The strut and cavity structure are important for the ignition and stable supersonic combustion of kerosene in the model scramjet. When a little hydrogen was injected with kerosene, the ignition and combustion performance was greatly improved. Too thick strut, too high equivalent fuel/air ratio, too much kerosene injected into the first combustor can make the combustor choke, consequently, affect the work of the isolator and air-heater nozzle.