高空低压低温环境航空发动机燃烧室熄火特性实验

航空发动机高空熄火是非常严重的安全威胁，高空燃烧稳定性与可靠再点火是航空发动机燃烧室的普遍要求.文章介绍了高空低压低温条件下航空发动机燃烧室模拟实验设备方案和调试结果，实现了对地面状态到高空10 km处环境条件的模拟.研究表明，随着高度增加，贫油熄火极限油气比不断增大.地面状态的贫油熄火油气比为0.016，高空10 km条件下，熄火油气比为0.071，增大3倍以上.低压低温环境下，火焰锋面位置不断向喷嘴收缩，燃烧释放热区域缩小到燃油喷嘴头部附近，CH*发光强度不断衰减.在模拟高度4 km时，火焰开始转为淡蓝色，10 km时燃烧室内为淡蓝色火焰，燃烧趋于不稳定. 

Experimental Study on Blowout Characteristics of Aeroengine Combustor under High Altitude Low Pressure and Low Temperature Condition

Flameout at high altitude is a serious security threat for the aircraft engine. Stable combustion and reliable reignition at high altitude are basic requirements for the combustor of the aircraft engine. The design and debugging results of the simulated altitude test facility (TSATF) were introduced in this paper. The simulation of high-altitude condition from ground state to 10 km was realized by TSATF. Results show that the fuel-air-ratio (FAR) of lean blow-out (LBO) limit rises with the mcrease of simulation altitude. The FAR of the LBO limit at ground state was 0.016. The FAR of the LBO limit at 10 km was 0.071, which increased three times than ground state. At low-temperature and low-pressure environment, the position of flame front decreased continuously. The area of heat released from combustion was limited near the fuel nozzle with the luminous intensity of CH* decreasing continuously. The flame in the combustor began to show light blue at the simulation altitude of 4 km, and turned to light blue completely at the simulation altitude of 10 km meaning that. Then the combustion tended to be unstable.