This paper studies the mathematical implications of the two dimensional viscous steady laminar combined free-forced convective flow of an incompressible fluid over a semi infinite fixed vertical porous plate embedded in a porous medium. It is assumed that the left surface of the plate is heated by convection from a hot fluid which is at a temperature higher than the temperature of the fluid on the right surface of the vertical plate. To achieve numerical consistency for the problem under consideration, the governing non linear partial differential equations are first transformed into a system of ordinary differential equations using a similarity variable and then solved numerically under conditions admitting similarity solutions. The effects of the physical parameters of both the incompressible fluid and the vertical plate on the dimensionless velocity and temperature profiles are studied and analysed and the results are depicted both graphically and in a tabular form. Finally, algebraic expressions and the numerical values are obtained for the local skin-friction coefficient and the local Nusselt number.
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A finite-difference solution to the unsteady free and forced convection flow of a dissipative fluid through a homogeneous porous medium past an infinite vertical isothermal plate is derived. Velocity and temperature profiles are shown graphically whereas the numerical values of the skin-friction and the rate of heat transfer are listed in a table. It is observed that the velocity decreases when the permeability parameter 'sigma' or the Grashof number G or the Eckert number E increase. Temperature and the rate of heat transfer are found to increase with increasing 'sigma' but the skin-friction decreases with increasing 'sigma'. The skin-friction decreases with increasing 'sigma'. The skin-friction increases but the rate of heat transfer decreases with increasing G, E (Eckert number) or time t.
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A regular perturbation analysis is presented for the laminar natural convection flows of micropolar fluids with temperature dependent viscosity: a freely-rising plane plume, the flow above a horizontal line source on an adiabatic surface (a plan wall plume) and the flow adjacent to a vertical uniform flux surface. While these flows have well-known power-law similarity solutions when the fluid viscosity is taken to be constant, they are non-similar when the viscosity is considered to be a function of temperature. A flow adjacent to a vertical isothermal surface is also analyzed for comparison in order to estimate the extent of validity of the perturbation analysis. The formulation used here provides a unified treatment of variable viscosity effects on those four flows. Computed first-order perturbation quantities are presented for all four flows. The velocity, microrotation distribution, temperature and concentration profiles are shown. Numerical results are presented for the local Nusselt number and Sherwood number, wall shear stress and wall couple stress.
Combined free and forced convection flow of water at 4oC has been studied when the free-stream is of the form exp (mx/2) where m is a constant and x is the distance measured along the semi-infinite vertical plate from the leading edge. Similarity solutions are obtained and the velocity and temperature profiles are shown on graphs, whereas the numerical values of the skin-friction and the rate of heat transfer are listed in a table. The effects of the fall in the temperature of water from 20oC to 4oC are discussed. Also the effects of Gr/Re2 (Gr - the Grashof number and Re - the Reynolds number) on the skin friction and the heat transfer are discussed.
Combined free and forced convection flow of a viscous incompressible fluid past a semi-infinite vertical plate embedded in a homogeneous porous medium is studied here. With usual boundary layer transformations, the equations are reduced to local non-similar forms and these are solved numerically on a computer. Velocity and temperature profiles are shown graphically and the numerical values of the skin-friction and the rate of heat transfer are listed in a table. The effects of the parameters Gr/Re2 (Gr - Grashof number Re - the Reynolds number), 'alpha' (coefficient of viscosities of the fluid and porous medium), 'sigma' (the Darcy number), Pr (the Prandtl number) and E (the Eckert number) on the flow field are discussed.
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