Abstract Flow past stationary and oscillating square cylinders at Reynolds number 22,000 are studied using immersed boundary method (IBM) in large eddy simulation (LES), as the IBM is able to seamlessly simulate arbitrarily-moving bodies at a high efficiency. The square cylinders are forced to oscillate in a prescribed sinusoidal motion at reduced velocity 7.7, which corresponds to the resonance point. Two amplitude ratios A ∕ D = 0.05 and 0.1 based on a cylinder height D are studied. The accuracy of the current solver with the immersed boundary method is rigorously assessed against the reference data. To understand the effect of structural motion on the flow and turbulence, aerodynamics of the oscillating cylinder is compared with that of the stationary cylinder. It is found that the oscillation motion reduces the spanwise correlation of flow field and triggers earlier reattachment on the side faces. Consequently, more chaotic surface pressure is generated downstream the reattachment point, and a smaller correlation is observed between upper and lower surface pressures. This helps to fully understand the interaction of turbulence and the flow-induced motion of a structure.

中文翻译：

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流过静止和摆动方圆柱体的大涡模拟

摘要 使用浸入边界法 (IBM) 在大涡模拟 (LES) 中研究通过雷诺数为 22,000 的静止和振荡方圆柱体的流动，因为 IBM 能够高效无缝地模拟任意运动的物体。方柱体被迫以规定的正弦运动以 7.7 的减速速度摆动，这对应于共振点。研究了基于圆柱高度 D 的两个振幅比 A ∕ D = 0.05 和 0.1。使用浸入边界法的当前求解器的准确性根据参考数据进行了严格评估。为了理解结构运动对流动和湍流的影响，将摆动圆柱体的空气动力学与静止圆柱体的空气动力学进行比较。发现振荡运动降低了流场的展向相关性并触发了侧面的早期再附着。因此，在再附着点下游产生了更多的混沌表面压力，并且观察到上表面压力和下表面压力之间的相关性较小。这有助于充分了解湍流与结构的流动引起的运动之间的相互作用。