Abstract

Physical experiment and direct numerical simulation are employed to study a transitional flow of viscous fluid past a spanwise circular cylinder mounted near the wall of a rectangular channel. The Reynolds number varies in the range of 60 to 480. Spiraling tornado-like motion of fluid directed from the sidewalls toward the center of the channel behind the cylinder is discovered. The evolution of this motion with the Reynolds number is outlined. Formation of large-scale vortical structures (analogue of Karman vortex street) and their turbulent breakdown in the cylinder wake are described. The behavior of the drag coefficient of the cylinder and the nearest wall with the Reynolds number is revealed.

中文翻译：

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在中等雷诺数下通过靠近通道壁的圆柱的横流中的涡流模式

摘要

采用物理实验和直接数值模拟来研究粘性流体通过安装在矩形通道壁附近的展向圆柱体的过渡流动。雷诺数在 60 到 480 的范围内变化。发现流体从侧壁流向圆柱体后面通道中心的螺旋状龙卷风运动。概述了这种运动与雷诺数的演变。描述了大型涡流结构（类似于卡门涡街）的形成及其在圆柱尾流中的湍流击穿。揭示了具有雷诺数的圆柱体和最近壁的阻力系数的行为。