Abstract We performed direct simulations of channel flow subjected to rotation about a spanwise axis, comparing cases with smooth and rough walls. The destabilizing effect of roughness counteracts the stabilizing effect of rotation on the cyclonic (stable) side. When the surface is rough the Reynolds stresses remain significant at all rotation rates considered, even those that results in a quasi-laminar state when the wall is smooth. The wake fluctuations result in significant dispersive stresses, which give an important contribution to the generation of turbulence on the stable side, mainly through added production of shear stresses. The dispersive stresses are mostly associated with the channeling of the flow between roughness elements.

中文翻译：

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粗糙壁旋转通道中的湍流统计

摘要 我们对受绕展向轴旋转的通道流动进行了直接模拟，比较了光滑和粗糙壁的情况。粗糙度的不稳定作用抵消了旋风（稳定）侧旋转的稳定作用。当表面粗糙时，雷诺应力在所有考虑的旋转速率下仍然显着，即使是那些在壁光滑时导致准层状状态的应力。尾流波动导致显着的分散应力，这对稳定侧湍流的产生有重要贡献，主要是通过增加剪切应力的产生。分散应力主要与粗糙元素之间的流动通道有关。