超燃冲压发动机二维凹腔剪切层数值研究(英文)  

Numerical Study of Shear Layer over Two-dimensional Cavity for Scramjet Applications

作　　者：汪洪波[1] 孙明波[1] 吴海燕[1] 王振国[1] 

机构地区：[1]国防科技大学航天与材料工程学院,湖南长沙410073

出　　处：《系统仿真学报》2008年第19期5305-5310,共6页Journal of System Simulation

基　　金：National Natural Science Foundation of China (90505009)

摘　　要：数值研究了冷流及反应流情况下超燃冲压发动机二维凹腔剪切层的非定常特性。应用混合RANS/LES方法预报非定常流场,该模型很好地捕捉到了非定常大尺度结构并揭示了凹腔剪切层的演化。着重研究了凹腔上游横向喷流和燃烧放热对凹腔剪切层行为的影响。结果表明:凹腔上游横向喷流使凹腔剪切层增厚并上抬,同时减弱了剪切层与凹腔后壁的撞击,明显抑制了凹腔-剪切层自激振荡;燃烧发生后,凹腔剪切层进一步上抬,凹腔自激振荡大幅减弱,同时压力振荡转到相对较低的频率。The unsteady behaviors of shear layer over a two-dimensional cavity for scramjet applications within supersonic cold flow and reactive flow were investigated numerically in the present study. Calculations used hybrid RANS/LES method to predict unsteady state flow fields. The hybrid model favorably captured the large scale unsteadiness and revealed the evolvement of cavity shear layer. The effects of transverse fuel injection upstream of the cavity and heat release on the unsteady behaviors of the shear layer were studied in particular. The hybrid RANS/LES data suggest that transverse injection upstream of the cavity thickens and raises the cavity shear layer, and weakens the intensity of the impingement between shear layer and cavity aft wall, which suppresses the cavity-shear layer self oscillation obviously. The cavity shear layer is raised farther and the cavity oscillation becomes much weaker when combustion occurs. Meanwhile, pressure fluctuation spectra shift to relative lower frequencies.

关 键 词：混合RANS/LES 凹腔剪切层 非定常 自激振荡 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]