污染效应对超声速燃烧室贫油熄火极限影响实验研究

Experimental Study of Vitiation Effects on Supersonic Combustor Blowout Limit

关键词:  超声速燃烧室  直连式实验  污染效应  贫油熄火极限  平面激光诱导荧光

Key words:  Supersonic combustor  Direct-connect experiment  Vitiation effects  Lean blowout limit  PLIF

摘要:

针对污染效应对超声速燃烧室熄火性能影响问题，采用甲烷燃烧和电阻加热的燃烧室直连式对比实验方法，开展了污染效应对燃烧室贫油熄火极限影响研究。基于超声速燃烧室实验模型，研究了煤油喷嘴结构对贫油熄火极限的影响；采用高速摄像仪和平面激光诱导荧光技术（PLIF），研究了加热方式对贫油熄火极限的影响，获得了光学测量结果和壁面压力分布，给出了纯净来流和污染来流条件下的燃烧室贫油熄火极限。研究表明：采用甲烷燃烧加热的燃烧室贫油熄火极限对应的当量比高于电阻加热的，分别为0.135和0.105；不同加热方式来流条件下，超声速燃烧室在燃烧不同阶段的稳定模式均为凹槽火焰稳定模式，火焰基底会呈现一定程度的脉动，但稳定在凹槽剪切层内。

Abstract:

In order to investigate vitiation effects on supersonic combustor blowout limit， comparative tests are conducted in a supersonic combustor using the direct-connected electrical heating facility and methane combustion heating facility. Based on the supersonic combustor test model， the effects of injector configurations on the lean blowout limit of combustor model are studied. And also the effects of heating methods on the lean flameout limit are studied by using high-speed camera and planar laser induced fluorescence technology （PLIF）. Combined with flame luminosity image， kerosene-PLIF image， OH & kerosene-PLIF image and wall pressure distribution， the lean blowout limit under the clean air and vitiated air are obtained. The results show that the lean blowout limit equivalence ratio for methane combustion heated airflow and electrical heated airflow is 0.135 and 0.105， respectively. The flame stability mode of supersonic combustor is groove flame stability mode in each combustion stage under the condition of different heating modes. The flame base will show a certain degree of pulsation， but it is stable in the groove shear layer.