An unstable laminar flow over a wavy region of a plate placed parallel to the oncoming air flow is studied. The results have been obtained by the hot-wire method in a low-turbulent wind tunnel at low subsonic velocities. Flow near a wall with transverse undulation, whose amplitude is sufficiently large and can contribute to the formation of local regions of boundary layer separation, is considered. The external harmonic (acoustic) forcing of the periodic flow leads to the suppression of perturbations that dominate in the spectrum of velocity disturbances near the model surface. The results of this work may be useful in developing methods for controlling spatially inhomogeneous flows.

中文翻译：

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层流边界层分离时空间周期流动的稳定性

研究了平行于迎面而来的气流的波状区域上不稳定的层流。通过热线法在低亚音速下在低湍流风洞中获得了结果。考虑到具有横向起伏的壁附近的流动，该壁的振幅足够大并且可以有助于边界层分离的局部区域的形成。周期性流动的外部谐波（声）强迫导致抑制了扰动，扰动在模型表面附近的速度扰动谱中占主导地位。这项工作的结果可能对开发用于控制空间不均匀流的方法很有用。