Investigation on Unsteady Interaction Phenomena of Shock Waves and Turbulent Boundary Layers in Supersonic Internal Flows

对超燃冲压发动机进气道和隔离器相关的矩形通道内存在激波的超音速内部流动进行了实验和数值研究。实验结果总结如下：(1)通过彩色照相和管道壁面压力脉动测量，研究了马赫数为2和4的PSWs的位置、内部结构和特性。结果表明，在均匀流动马赫数M∞=2时，方管内出现了几何对称的λ型脉冲波。当马赫数M∞=4时，管道内出现X型脉冲波，并出现与顶壁或底壁偏离很大的不对称流动。(2)当M_∞=2时，脉冲波第一激波作用下，壁面压力发生较大波动，而当M_∞=4时，脉冲波…第一激波和第二激波作用下壁面压力波动较大(3)用剪切灵敏液晶对PSWs的壁面剪应力进行了定性的可视化，并用自制的剪应力传感器进行了定量测量。结果表明，在马赫数为4时，顶壁边界层分离区存在反向流动，分离后的附面层重新附着，壁面剪应力的大小如何变化。数值模拟采用Harten-Yee二阶TVD格式和Baldwin-Lomax湍流模型。结果表明：(4)对于马赫数为2的PSW，计算结果与实验结果吻合较好。(5)对于马赫数为4的PSW，由于实验中的不对称特性，计算结果与实验结果有一定的差异，而这些差异在模拟中是不能再现的。然而，计算结果对于理解复杂的不对称现象是有价值的。较少

Experimental and numerical investigations on the supersonic internal flows with shock waves, i.e., so called Pseudo-Shock Wave ( PSW) phenomena in rectangular ducts related to scramjet engine isolators and intakes, were conducted. Experimental results are summarized as follows:(1) The location, internal structure and characteristic of the Mach 2 and 4 PSWs were investigated by color shlieren photographs and duct wall pressure fluctuation measurements. As the results, it was revealed that in the case of uniform flow Mach number M∞= 2, λ-type PSW with symmetric geometry occurs in the square duct. In the case of Mach number M∞= 4, an X-type PSW occurs in the duct, and an asymmetric flow which deviates greatly to top or bottom wall appears.(2) In the case of M_∞= 2, large wall pressure fluctuations due to the PSW oscillations occur under the first shock wave of the PSW, while in the case of M_∞= 4, the large wall pressure fluctuations occur under the first and second shock waves of the PSW … More .(3) The wall shear stresses in PSWs were visualized qualitatively by shear-sensitive liquid crystal, and measured quantitatively by the hand made shear stress transducer. As the results, it was revealed that in the case of Mach 4 PSW reverse flows exist in the top wall boundary layer separation region, and that the separated boundary layer on the top wall is reattached, and how the magnitude of the wall shear stress change in the PSW. It was also revealed that the bottom wall boundary layer separates widely in the PSW and the reverse flow exist in the separation region.Numerical simulations were carried out using the Harten-Yee second order TVD scheme and the Baldwin-Lomax turbulence model. Numerical results are summarized as follows:(4) The computational results for the Mach 2 PSW are in good agreement with the experimental results.(5) In the case of Mach 4 PSW, the several differences were found between the computational results and experiments due to asymmetric characteristics in the experiment which could not be reproduced in the simulation. However, the computational results are valuable for understanding the complex asymmetric phenomena. Less