A linear stability analysis is applied to a system consisting of three horizontal layers, a viscous fluid layer sandwiched between two porous medium permeated by the fluid that the lower layer is heated uniformlly from below. Flow in the porous medium is assumed to be governed by Darcy’s law. The Beavers-Joseph condition is applied at the interface between any two different layers.Spectral meth...

Unsteady oscillatory flow of generalized Burgers’ fluid in a circular channel tube in the porous medium is investigated under the influence of time-dependent trapezoidal pressure gradient given by an infinite Fourier series. An exact analytical expression for the solution for the fluid velocity and the shear stress are recovered by using the similarity arguments together with the integral trans...

In this paper the two-dimensional flow of a micropolar fluid through porous medium over a continuously moving porous vertical plate under the combined buoyancy effects of thermal and heat source has been studied under the action of transverse magnetic field taking into account the thermal radiation field. The Roseland approximation is used to describe radiative heat transfer in the limit of opt...

The effect of the magnetic field dependent (MFD) viscosity on the thermal convection in a ferromagnetic fluid in the presence of a uniform vertical magnetic field is considered for a fluid layer in a porous medium, heated from below. For a ferromagnetic fluid layer between two free boundaries an exact solution is obtained, using a linear stability analysis. For the case of stationary convection...

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...

The paper first discusses the real fluids circulating in the earth’s crust, and justifies the need to examine the natural convection in a porous medium of a simple pure fluid with properties resembling those near the thermodynamic critical point. The literature on natural convection in a homogenous porous medium between isothermal horizontal plates, the lower one hotter, is then reviewed. Resul...

In the present paper, we have studied MHD free convective two dimensional unsteady viscous incompressible flows through a porous effect bounded by an infinite vertical porous plate with constant suction. The permeability of the porous medium fluctuates in time about a constant mean, and the viscosity of fluid is assumed to vary as a linear function of temperature. The flow is permitted under th...

A fuel cell is an electro-chemical tool capable of converting chemical energy into electricity. High operating temperature of solid oxide fuel cell, between 700oC to 1000oC, causes thermal stress. Thermal stress causes gas escape, structure variability and cease operation of the SOFC before its lifetime.The purpose of the current paper is to present a method that predicts ...

Unsteady flow with magneto-hydrodynamics and heat generation through porous medium past an impulsively started vertical plate with constant wall temperature and mass diffusion is considered here. The effect studied is a combination of Hall current and chemical reaction. The motivation behind this study is the applications of such kind of problems in industry. In many industrial applications ele...

In this study, the linear stability of an unsteady thermal boundary layer in a semi-infinite porous medium is considered. This boundary layer is induced by varying the temperature of the horizontal boundary sinusoidally in time about the ambient temperature of the porous medium; this mimics diurnal heating and cooling from above in subsurface groundwater. Thus if instability occurs, this will h...