In this work, we first reformulate the unsteady flow of gas through a porous medium problem in [0,+∞) to a problem in [-1,1] by variable transformation μ = (x-s)/(x+s), and using spectral collocation method based on Chebyshev polynomials to approximate the resulting problem. The comparison of the results obtained by this method with results obtained by other methods shows that this method provi...

The effect of non-uniform heat generation on an unsteady MHD laminar boundary layer flow of viscous, incompressible fluid over a vertical stretching plate embedded in a sparsely packed porous medium is investigated numerically. The flow in the porous medium is governed by Brinkman-Forchheimer extended Darcy model. The variation of porosity, permeability and thermal conductivity is assumed. By a...

The purpose of present problem is to studies of effects of variable viscosity and heat source on unsteady laminar flow of dusty conducting fluid between parallel porous plates through porous medium with temperature dependent viscosity. The fluid is considered as unsteady laminar flow through porous medium and acted upon by a constant pressure gradient and an external uniform magnetic field is a...

A global nonlinear stability analysis is performed for a couple-stress fluid layer heated from below saturating a porous medium with temperature-pressure dependent viscosity for different conducting boundary systems. Here, the global nonlinear stability threshold for convection is exactly the same as the linear instability boundary. This optimal result is important because it shows that lineari...

A finite-element simulation of binary alloy solidification based on a single-domain formulation is presented and tested. Resolution of phase change is first checked by comparison with the analytical results of Worster [M.G. Worster, Solidification of an alloy from a cooled boundary, J. Fluid Mech. 167 (1986) 481–501] for purely diffusive solidification. Fluid dynamical processes without phase c...

The steady free convection boundary layer over a vertical cone embedded in a porous medium filled with a non-Newtonian fluid with an exponential decaying internal heat generation is studied in this paper. We adopt for the non-Newtonian fluid the well-known model of a power-law fluid. Two cases are considered, Variable Wall Temperature (VWT) and Variable Heat Flux (VHF), respectively. As for the...

This paper describes a theoretical study to investigate the heat transfer characteristics of porous radiant burners. A one dimensional model is used to solve the governing equations for porous medium and gas flow before the premixed flame to the exhaust gas. Combustion in the porous medium is modeled as a spatially dependent heat generation zone. The homogeneous porous media, in addition to its...

A free convective unsteady visco-elastic flow through porous medium bounded by an infinite vertical porous plate with variable suction, constant heat flux under the influence of transverse uniform magnetic field along with permeability in the presence of radiation has been investigated in the present study. The suction velocity of the porous medium fluctuates with time about the constant mean. ...