Unsteady stagnation point flow on the surface of a quiescent fluid
Abstract
The selfsimilar solution is considered for the unsteady incompressible twodimensional and axisymmetric stagnationpoint flow with or without a magnetic field. The case is considered where a lighter fluid impinges downward on a heavier otherwise quiescent fluid. The governing equations are solved numerically using a shooting method. Analytical solutions are also obtained for certain limiting cases. Results show that the selfsimilar solution exists only when the free stream velocity decreases with time or remains constant. The shear stress parameters for both upper and lower fluids decrease as the deceleration parameter increases, but the heat transfer parameters increase. For the upper fluid, both shear stress and heat transfer increase with the magnetic field, but, for the lower fluid, the shear stress increases and the heat transfer decreases as the magnetic parameter increases. The interface velocity effect is more pronounced on the skin friction than on the heat transfer. For both fluids, the Prandtl number strongly affects the heat transfer rates.
 Publication:

Acta Technica
 Pub Date:
 1988
 Bibcode:
 1988AcTec..33..715S
 Keywords:

 Axisymmetric Flow;
 Computational Fluid Dynamics;
 Incompressible Flow;
 Stagnation Point;
 Two Dimensional Flow;
 Unsteady Flow;
 Heat Transfer;
 Magnetic Fields;
 Prandtl Number;
 Shear Stress;
 Skin Friction;
 Velocity Distribution;
 Wall Temperature;
 Fluid Mechanics and Heat Transfer