Novel bifurcation phenomena in a rotating annulus

We present an experimental and numerical study of a novel variant of the Taylor–Couette problem. The ends of the annular region rotate with the inner cylinder producing a strong, symmetric forcing of the flow. One consequence of the imposed forcing is that asymmetric flows are more readily found than in the standard stationary-ends case. This has led to the discovery of several new and interesting bifurcation phenomena, including codimension-two points of a type normally associated with chaos in finite-dimensional dynamical systems.