When multiple streaklines are introduced along a line, this configuration is referred to as a rake of streaklines. Because of the unsteady vortices shed from the cylinder in an alternating pattern, the smoke collects into a clearly defined structure known as a Kármán vortex street

Streak lines can be computed efficiently by simple curve integration. In the 2D time-dependent flow around a cylinder, the von Kármán vortex street is revealed by the rolling-up behavior of streak lines, which becomes more pronounced for larger values of the streak-line age parameter