燃烧室燃烧与排放特性试验与数值计算

为了探寻燃烧室进口空气温度、压力以及油气比对点熄火边界、温升、燃烧效率以及主要排放物摩尔分数的影响规律， 对航空发动机燃烧室在多工况下的点熄火特性、出口温度分布与主要排放物摩尔分数进行了试验测试。分别采用正癸烷的简化 反应机理与C 12 H 23 燃料的单步反应机理，对该燃烧室火焰筒内流场结构、温度场、中间组分与主要排放物摩尔分数分布特性进行了 数值计算，并与相应试验数据进行了对比分析。结果表明：随着燃烧室进口空气温度、压力以及油气比的提高，燃烧室燃烧效率、 温升、出口平均温度与NO X 摩尔分数逐渐提高，而UHC与CO摩尔分数逐渐降低；与采用C 12 H 23 燃料单步反应机理相比，采用正癸 烷的简化反应机理计算得到的火焰筒内流场与温度场分布更为合理，火焰筒出口温度场分布以及主要排放物摩尔分数与相应试 验数据更为接近，计算精度得到较大提高。

Experiment and Simulation on Combustion and Emission Characteristics of an Aero-engine Combustor

In order to explore the influences of inlet air temperature, pressure and fuel-air ratio on the ignition and flameout boundar? ies, temperature rise, combustion efficiency and main emissions mole fraction, tests were conducted on the ignition and flameout character? istics, outlet temperature distribution and main emissions mole fraction of an aeroengine combustor under different operating conditions. The structure of flow field, the distributions of temperature field, intermediate species and main emissions mole fraction fields in the flame tube were simulated by using the reduced reaction mechanism of n-decane and the single step reaction mechanism of C 12 H 23 respectively, and the computational results were compared with the corresponding experimental data. The results show that with the increase of inlet air temperature, pressure and fuel-air ratio of the combustor, combustion efficiency, temperature rise, outlet average temperature and NOX mole fraction gradually increase, while UHC and CO mole fraction gradually decrease. Compared with the single step reaction mechanism of C 12 H 23 , when adopting the reduced reaction mechanism of n-decane, the distributions of flow field and temperature field in the flame tube are more reasonable, the distributions of temperature field and main emissions mole fraction at the flame tube outlet are closer to the experimental data, and the calculation accuracy is greatly improved.