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采用大涡模拟(LES)方法对平面超声速引射器的内部流动进行了数值研究。为了验证LES方法的可靠性,对计算结果和实验数据进行了定量对比,对比的物理量有速度和温度剖面。结果表明当前计算结果和实验数据吻合得较好,这说明LES方法能够有效地研究此类问题。引射器主射流的失稳过程与自由射流的失稳过程相同,分为增长、失稳和混合3个阶段。Lamb矢量散度的分布表明,混合室内部的混合过程被限制在狭小的带状区域。混合室内压力信号的功率谱分析表明,主射流的失稳主导着混合室内部流体的混合过程,其特征St数约为0.27。
A large eddy simulation (LES) method was used to study the internal flow of a planar supersonic ejector. In order to verify the reliability of the LES method, the calculated results and experimental data were quantitatively compared with the velocity and temperature profiles of the compared physical quantities. The results show that the current calculation results agree well with the experimental data, which shows that the LES method can effectively study such problems. The instability process of ejector main jet is the same as the instability process of free jet, which is divided into three stages: growth, instability and mixing. The distribution of the Lamb vector divergence shows that the mixing process inside the mixing chamber is confined to a narrow zone of banding. Power spectrum analysis of mixed chamber pressure signal shows that the main jet instability dominates the mixing process of the fluid inside the mixing chamber, and the characteristic St number is about 0.27.