Boundary layer separation over a rotating cylinder in a flow of an incompressible fluid

The problem of a two-dimensional plane-parallel flow of a viscous incompressible fluid past a rotating cylinder is solved numerically assuming a boundary layer with a given pressure gradient. The latter is determined from the external nonviscous flow. The ratio of the rotational velocity to the velocity of the incoming flow that corresponds to the onset of separation is obtained, and the point at which the separation is initiated is determined. The results obtained for nonseparated flow are in good agreement with the small-perturbation solution.