Abstract The existence and properties of the logarithmic layer in a turbulent streamwise oscillating flow are investigated through direct numerical simulations and wall-resolved large-eddy simulations. The phase dependence of the von Kármán constant and the logarithmic layer intercept is explored for different values of the Reynolds number and the depth-ratio between the water depth and the Stokes boundary layer thickness. The logarithmic layer exists for a longer fraction of the oscillating period and a larger fraction of the water depth with increasing values of the Reynolds number. However, the values of both the von Kármán and the intercept depend on the phase, the Reynolds number and depth-ratio. Additionally, the simulations characterized by a low value of the depth-ratio and Reynolds number show intermittent existence of the logarithmic layer. Finally, the Reynolds number based on the friction velocity does not support a previously mentioned analogy between oscillatory flows and steady wall-bounded flows.

中文翻译：

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振荡流中对数层的存在和性质

摘要 通过直接数值模拟和壁面分辨大涡模拟研究了湍流振荡流中对数层的存在和性质。针对不同雷诺数值和水深与斯托克斯边界层厚度之间的深度比，探索了冯卡门常数和对数层截距的相位依赖性。随着雷诺数值的增加，对数层存在于振荡周期的较长部分和水深的较大部分。然而，von Kármán 和截距的值取决于相位、雷诺数和深度比。此外，以低深度比值和雷诺数为特征的模拟显示对数层的间歇性存在。最后，基于摩擦速度的雷诺数不支持前面提到的振荡流和稳定壁面流之间的类比。