Abstract The wake flow characteristics of a spherical bubble against the interface contaminated degree are deeply investigated at moderate Reynolds number (Re = 25–200) based on the 3D rear stagnant cap model. The interface contaminated degree is controlled by changing the magnitude of the cap angle, for θ = 0–180°. It is found that the vortex size does not change obviously when θ = 0–67.5°; when θ > 67.5°, it decreases until it is equal to zero when θ > 135°. The variations of vortex size and separation angle are related to the deceleration of fluid near the lee face of the bubble. The vortexes display the 3D characteristic due to the skip of pressure coefficient component in the flow direction at the leading edge of the stagnant cap when θ = 45°, 67.5°, 112.5° and 135°.

中文翻译：

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等温流动条件下界面污染程度对中等雷诺数球形气泡尾流特性的影响

摘要 基于3D后滞流帽模型，在中等雷诺数（Re = 25-200）下，针对界面污染程度的球形气泡尾流特性进行了深入研究。界面污染程度通过改变帽角的大小来控制，θ = 0-180°。发现当θ=0-67.5°时，涡流大小没有明显变化；当 θ > 67.5° 时，它减小直到 θ > 135° 时为零。涡流大小和分离角的变化与气泡背风面附近流体的减速有关。当 θ = 45°、67.5°、112.5° 和 135° 时，由于在滞流帽前缘处的流动方向上的压力系数分量跳过，涡流显示 3D 特性。