Destabilization of inertio-elastic mode via spatiotemporal intermittency in a Couette-Taylor viscoelastic flow
Résumé
We have characterized the transition to turbulence in a flow with semi-dilute solutions (concentration of 0.07%) of polyethylene oxide (PEO) in the Couette-Taylor system with rotating only the inner cylinder. The first instability mode occurs via a supercritical Hopf bifurcation in form of interacting right and left spirals. For higher values of the rotation velocity, turbulent spots appear in the flow and coexist with the spirals. This spatio-temporal intermittency (STI) regime has been characterized by the turbulent fraction and the statistical properties of the laminar domains.