Symmetry breaking and multiplicity of states in small aspect ratio Taylor–Couette flow

We report the results of an experimental and numerical study of the bifurcation structure of steady cellular states in small aspect ratio Taylor–Couette flows. In particular we focus on Z 2 symmetry-breaking bifurcations where asymmetric states which break the mid-plane symmetry arise. We find good quantitative agreement between numerical and experimental results for the bifurcation set. The surprising new observation we make is that the symmetry-breaking bifurcation sequences coalesce in a self-consistent way as the aspect ratio is reduced so that only symmetric steady flows exist for very short cylinders. The implications of this for the onset of disordered motion are discussed.