Mechanisms for the transition to waviness for Taylor vortices

Articles you may be interested in Boundary layer dynamics at the transition between the classical and the ultimate regime of Taylor-Couette flow Building on the weakly nonlinear amplitude equation of the saturated Taylor vor-tices developing in a Taylor–Couette cell with a rotating inner cylinder and a fixed outer one, the physical mechanism underlying the destabilization of these vortices resulting in azimuthal waviness is addressed using Floquet analysis. For narrow gap configurations, analysis and direct numerical simulations together with existing experimental results support the idea that the waviness is generated by the axial shear in the azimuthal velocity due to the alternate advection by the Taylor vor-tices of azimuthal momentum between the cylinders. For wide gap configurations, this mechanism is no longer able to drive the azimuthal waviness and a different mechanism tends to select a subharmonic instability. C 2014 AIP Publishing LLC.