Symmetry breaking of the flow in a cylinder driven by a rotating end wall

The flow driven by a rotating end wall in a cylindrical container with aspect ratio H/R=2.5 is time dependent for Reynolds numbers Re=Omega R-2/nu > 2700. For Reynolds numbers up to 4000 three solution branches have been identified, and we examine a solution on each one. At Re=3000, the flow is axisymmetric and time periodic. At Re=3500, the flow is quasiperiodic with a low-frequency modulation and supports a modulated rotating wave with azimuthal wave number k=5. At Re=4000, the flow is time periodic with a qualitatively different mode of oscillation to that at Re=3500. It also supports a modulated rotating wave, with k=6. The peak kinetic energy of the nonaxisymmetric modes is associated with the jet-like azimuthal flow in the interior. (C) 2000 American Institute of Physics. [S1070- 6631(00)00311-1].