How Does Turbulence Get Started? (2014)

In 2004, Bruno Eckhardt of the University of Marburg and Rich Kerswell of the University of Bristol discovered, at least in theory, an elusive third state between laminar flow and turbulence called a traveling wave. The experiment is rooted in the 2003 discovery by Eckhardt and Kerswell of the first bona fide mathematical solutions, aside from laminar flow, to the Navier-Stokes equations in a pipe. Hof’s experiment has proved that Eckhardt was right: Puffs continue to have a finite life span even above Reynolds number 2,000.

Source: nautil.us