Axisymmetric Vortex Breakdown in an Enclosed Cylinder Flow

The attraction of the confined swirling flow generated inside an enclosed cylinder by the constant rotation of one of its endwalls to a study of vortex breakdown is that the flow is defined by only four variables, these being the height H and radius R of the cylinder, the constant angular speed of rotation of the endwall f~ and the kinematic viscosity t~. These four variables are used to define two non-dimensional parameters which completely specify the flow conditions the aspect ratio H/R and a rotational Reynolds number Re = ~R2/r,. The boundary conditions are also defined precisely since the flow is confined in a fixed volume. As Re and/or t t / R are increased beyond critical values, the central vortex core undergoes breakdown.