Abstract In this study, experimental investigations of the flow pattern around an oblong pier (OP) mounted on a rigid flat surface are carried out in a laboratory flume and the results are compared with that of a circular pier (CP) for better understanding of the flow hydrodynamics applicable to scour. The novelty of this work is the study of turbulence characteristics such as mean velocities, Reynolds stresses, turbulent kinetic energy and the contributions of burst-sweep cycles to the total Reynolds shear stresses along the oblong and the circular piers and their inter-comparison, which have not been previously addressed. Application of power spectral analysis suggests that the peak values of vortex shedding frequency for OP are higher than those of CP, indicating lower wake instabilities for OP. The influence of perturbed flow around the CP is considerably higher than that of OP, resulting in more scour around the CP, under identical flow conditions.

中文翻译：

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圆形和椭圆形码头周围引起冲刷的流动的湍流统计

摘要 在这项研究中，在实验室水槽中对安装在刚性平面上的椭圆形墩（OP）周围的流型进行了实验研究，并将结果与​​圆形墩（CP）的结果进行了比较，以更好地了解适用于冲刷的流动流体动力学。这项工作的新颖之处在于研究了湍流特性，例如平均速度、雷诺应力、湍流动能以及爆发-扫掠循环对沿长方形和圆形桥墩的总雷诺剪应力的贡献及其相互比较，其中以前没有解决。功率谱分析的应用表明，OP 的涡旋脱落频率峰值高于 CP，表明 OP 的尾流不稳定性较低。