Unsteady laminar boundary layer flow over a spinning body in free convection

Initial development of the unsteady laminar free-convection boundary-layer flow over an impulsively started spinning isothermal axisymmetrical vertical body is investigated. Stream function, swirl velocity and temperature are obtained in series of functions in powers of time. The general results are applied to a family of downward and upward thickening bodies to investigate the effects of the body shape on the formation of unseparated and separated boundary-layer flow regimes. The onset of flow separation is observed to take place at higher spin rates for downward thickening bodies. The surface heat flux is enhanced by the circulating flow inside the separated region. The series solutions are limited to the small values of the dimensionless time.