Streamwise vortices in plane Couette flow
Résumé
Experimental observations of various flows have led to the conclusion of the existence of streamwise vortices involved in the destabilization process of these flows. In the plane Couette flow, a linear shear flow, such structures have never been observed, because of the linear stability of the flow. The flow was slightly modified by introducing a wire in its central plane, parallel to the spanwise direction. A destabilization then occurs. It generates streamwise structures periodically spaced in the spanwise direction. These structures have been identified as pairs of counter‐rotating streamwise vortices. This Letter characterizes the dependence on the Reynolds number of the behavior of these vortices and how their destabilization leads to turbulence.