♦ Flow past an airfoil at high angle of attack shortly after a sudden start of motion. A marginal separation near the leading edge is followed by reattachment. The starting vortex is clearly seen.♦ Flow past the same airfoil at a later time. There is a substantial region of separation.♦ And even later.♦ This is an early stage of the development of the Karman vortex street behind a circular cylinder.♦ Flow past a car.♦ This is a spatially developing Karman vortex street: further downstream the vortices will gradually arrange themselves into the usual mutual position.
