The von Kármán vortex street

The von Kármán vortex street is a pattern of swirling air or fluid that forms behind a solid object, like a bridge pillar or a cylinder in a wind tunnel. When fluid flows past the object, it creates alternating regions of vortices—spiral-shaped flows—that shed on opposite sides. These vortices appear in a regular, repeating pattern downstream, resembling a street of alternating whirlpools. This phenomenon results from the instability in the flow and can cause vibrations or noise. It is an important concept in fluid mechanics, influencing engineering designs and understanding natural flows around structures.