Mixed Convection in Non-Newtonian Fluids along a Vertical Plate in Porous Media with Constant Surface Heat Flux

A non-similar boundary layer analysis is presented for the problem of mixed convection in power-law type nonNewtonian fluids along a vertical plate embedded in saturated porous medium. The boundary condition of uniform surface heat flux distribution is assumed. Mixed convection covers the heat transfer regime in which forced and free convection mechanisms are of a comparable magnitude, and as such both are considered in the analysis. Numerical results are presented for the details of the velocity and temperature fields. A discussion is provided for the effects of viscosity index and the surface mass transfer on the surface heat transfer rate. KeywordsMixed Convection; Porous Media; NonNewtonian Fluids Nomenclature f dimensionless stream function; g acceleration due to gravity [m s]; h heat transfer coefficient [W m K]; k thermal conductivity[W m K]; K permeability for the porous medium; L plate length [m]; n viscosity index; Nu Nusselt number; Pe Peclet number qw wall heat flux[W m]; Ra Rayleigh number; T Temperature [K]; u,v velocity components in x and y directions [m s]; U∞ free stream velocity [m s]; x,y axial and normal co-ordinates[m]; α thermal diffusivity of porous medium [ms]; β volumetric coefficient of thermal expansion[K]; η similarity variable; θ dimensionless temperature; ν kinematic viscosity[ms]; ξ mass transfer parameter; ρ density of fluid[kg m]; μ consistency index for viscosity[kg ms]; τw wall shear stress [N m]; ψ stream function; Subscripts w wall conditions; ∞ free stream conditions;