Double diffusive unsteady free convection on two-dimensional and axisymmetric bodies in a porous medium
Article first published online: 14 MAR 2007
Copyright © 1989 John Wiley & Sons, Ltd.
International Journal of Energy Research
Volume 13, Issue 4, pages 379–391, 1989
How to Cite
Kumari, M. and Nath, G. (1989), Double diffusive unsteady free convection on two-dimensional and axisymmetric bodies in a porous medium. Int. J. Energy Res., 13: 379–391. doi: 10.1002/er.4440130402
- Issue published online: 14 MAR 2007
- Article first published online: 14 MAR 2007
- Manuscript Revised: MAY 1988
- Manuscript Received: DEC 1987
- Unsteady free convection;
- Porous medium;
- Magnetic field
The unsteady laminar free convection flow of an incompressible electrically conducting fluid over two-dimensional and axisymmetric bodies embedded in a highly porous medium with an applied magnetic field has been studied. The unsteadiness in the flow field is caused by the variation of the wall temperature and concentration with time. The coupled nonlinear partial differential equations with three independent variables have been solved numerically using an implicit finite-difference scheme in combination with the quasilinearization technique. It is observed that the skin friction, heat transfer and mass transfer increase with the permeability parameter but decrease with the magnetic parameter. The results are strongly dependent on the variation of wall temperature and concentration with time. The skin friction and heat transfer increase or decrease as the buoyancy forces from species diffusion assist or oppose the thermal buoyancy force. However, the mass transfer is found to be higher for small values of the ratio of the buoyancy parameters than for large values.