An exegesis of a novel mechanism leading to vortex splitting and subsequent shedding that is valid for two-dimensional incompressible, inviscid or viscous, and external or internal or wall-bounded flows, is detailed in this research. The mechanism, termed the vortex shedding mechanism (VSM) is simple and intuitive, requiring only two coincident conditions in the flow: (1) the existence of a location with zero momentum and (2) the presence of a net force having a positive divergence. Numerical solutions of several model problems illustrate causality of the VSM. Moreover, the VSM criteria is proved to be a necessary and sufficient condition for a vortex splitting event in any two-dimensional, incompressible flow. The VSM is shown to exist in several canonical problems including the external flow past a circular cylinder. Suppression of the von Kármán vortex street is demonstrated for Reynolds numbers of 100 and 400 by mitigating the VSM.

中文翻译：

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二维不可压缩流中涡旋脱落的成因

本研究详细解释了导致涡旋分裂和随后脱落的新机制，该机制适用于二维不可压缩、无粘性或粘性以及外部或内部或壁面流动。这种称为涡旋脱落机制 (VSM) 的机制简单直观，只需要流动中的两个重合条件：(1) 存在动量为零的位置和 (2) 存在具有正散度的合力. 几个模型问题的数值解说明了 VSM 的因果关系。此外，VSM 准则被证明是任何二维不可压缩流中涡旋分裂事件的充分必要条件。VSM 被证明存在于几个典型问题中，包括通过圆柱体的外部流。