Ray-tracing in high-speed boundary layers has been used to explore the potential for acoustic energy trapping as function of edge Mach number, wall temperature ratio, and thermodynamic parameters. We proposed a figure of merit for acoustic energy trapping as the critical angle of inclination for rays originating in the boundary that are trapped, i.e., these rays always stay within the boundary layer. Using this concept, we find that an increasing amount of acoustic energy is trapped with increasing edge Mach number (M_E), and decreasing wall temperature ratio (T_W/T_)(ad)). These trends agree qualitatively with the results of high-speed boundary layer stability calculation by Mack.
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机译：高速边界层中的光线跟踪已被用来探索声能捕获的可能性，该能量是边缘马赫数，壁温比和热力学参数的函数。我们提出了声能俘获的品质因数，作为对于被俘获的边界中的光线的临界倾斜角，即，这些光线始终停留在边界层内。使用这个概念，我们发现，随着边缘马赫数（M_E）的增加和壁温比（T_W / T _）（ad）的降低，声能的数量会增加。这些趋势在本质上与Mack的高速边界层稳定性计算结果一致。
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