Unsteady viscous flow past an impulsively started oscillating and translating elliptic cylinder

The unsteady two-dimensional flow of a viscous incompressible fluid past an impulsively started oscillating and translating elliptic cylinder has been investigated. The governing Navier-Stokes equations expressed in terms of a stream-function/vorticity formulation are solved numerically for the early stages of the flow for moderate to high Reynolds numbers. A boundary-layer type transformation was adopted to scale out the singular nature in the vorticity at the start of the motion. Some comparisons of the flow patterns with the impulsively started translating case have been included to illustrate the effect of oscillation. Wherever possible, comparisons with existing numerical results have been made and the agreement was found to be good.