基于基团法的冲压发动机燃烧室性能分析

Performance Analysis of Ramjet Combustor Based on Group Contribution Method

利用基团贡献法及变物性燃烧模型建立了冲压发动机燃烧室性能计算模型。利用模型分析了不同速度、海拔高度、余气系数条件下,燃烧室出口总温、加热比的变化。分析结果表明,性能计算模型可在基团法允许范围内,对不同来流条件下冲压发动机燃烧室的性能进行预估。对流层以内,马赫数越高、高度越低、余气系数越低则燃烧室出口总温越高,反之则越低;马赫数越低、高度越高、余气系数越小则加热比越大,反之则越低;进入平流层以后,出口总温和加热比随海拔高度的变化趋于平缓。

A performance calculation model of ramjet combustor was established by using group contribution method and variable physical property combustion model.The total temperature and heating ratio at the outlet of the combustor were analyzed by using the model under different velocities,altitudes and excess air coefficient.The analysis shows that the performance calculation model can predict the performance of ramjet combustor under different inflow conditions within the allowable range of group method.Within the troposphere,the higher the Mach number,the lower the height and the lower the excess air coefficient,the higher the total temperature of the combustor exit,and vice versa;the lower the Mach number,the higher the height and the smaller the excess air coefficient,the higher the heating ratio,and vice versa;after entering the stratosphere,the change of the total temperature and heating ratio at the exit tends to be gentle with the altitude.