基于火焰面/进度变量模型的超声速燃烧IDDES模拟

IDDES Simulation of Supersonic Combustion Based on Flamelet/Progress Variable Model

关键词:  超燃冲压发动机  湍流燃烧  火焰面/进度变量模型  IDDES模型

Key words:  Scramjet engine  Turbulent combustion  Flamelet/progress variable model  Improved delayed detached eddy simulation

摘要:

为了清晰地描述超声速条件下的复杂流动与燃烧过程，建立了基于IDDES模型和火焰面/进度变量模型的湍流燃烧数值模拟方法，并应用于德国宇航中心(DLR)超燃冲压发动机的数值模拟。计算结果与实验数据符合良好，表明该方法可以较为准确地描述超声速湍流燃烧过程，也验证了经过可压缩性修正的火焰面/进度变量模型适用于超声速燃烧问题的求解。同时，利用k-ω SST模型对同一算例进行了计算，发现其对物理量分布的计算精度要低于IDDES模型，说明湍流输运过程的描述对火焰面/进度变量模型的计算精度有重要影响。

Abstract:

In order to clarify complex processes of turbulent combustion in supersonic flows，a method combining IDDES model and flamelet/progress variable model is developed and then applied in the simulation of the German Aerospace Center(DLR)scramjet engine. The results show good agreements with experimental data，indicating that this method is able to predict supersonic turbulent combustion process accurately. The results also suggest that flamelet/progress variable model，with compressibility correction，is applicable in supersonic combustion modeling. As a comparison，k-ω SST model combined with flamelet/progress variable model is applied in the same case. It is found that the application of k-ω SST model leads to larger deviations compared with that of IDDES model，suggesting that the prediction of turbulent transport process has a significant effect on the precision of flamelet/progress variable model.