ASYMPTOTIC AND FINITE-ELEMENT APPROXIMATIONS FOR HEAT-TRANSFER IN ROTATING COMPRESSIBLE FLOW OVER AN INFINITE POROUS DISK

The problem of flow and heat transfer in the laminar compressible boundary layer over a rotating infinite disk is solved through analytical and numerical methods. Motions which are induced by a difference both in rotation and temperature rates including suction (or blowing) effects are studied. The laminar boundary layer equations for the compressible flow due to the finite difference in rotation and temperature rates are solved for the case of uniform suction through the disk. The effects of viscous dissipation on the incompressible flow are taken into account for any rotation rate, whereas for a compressible fluid they are considered only for a disk rotating in a stationary fluid. For the general case, the governing equations are solved numerically using a standard finite element scheme. Series solutions are developed for those cases where the suction effect is dominant. Based on the above analytical and numerical solutions, a new asymptotic finite element scheme is presented. By using this scheme one can significantly improve the pointwise accuracy of the standard finite element scheme.