Transient hydromagnetic radiative convection flow of a micropolar fluid past a moving semi- infinite vertical porous plate

Unsteady two-dimensional laminar radiative convection flow of an incompressible, electrically conducting micropolar fluid past a moving semiinfinite vertical porous plate in the presence of magnetic field is studied. The effects of material parameters on the velocity and temperature fields are investigated. The Rosseland approximation is used to describe the radiative heat flux in the energy equation. The micropolar fluid is considered to be gray, absorbing-emitting but non-scattering optically thick medium. Numerical results of velocity field and temperature distribution are discussed with the help of figures, while skin-friction and rate of heat transfer are discussed by the use of tables. It is observed that when radiation parameter increases, the velocity increases and temperature decreases, whereas an increase in Grashof number or magnetic parameter decreases the velocity. 197 NOMENCLATURE: u ', v' dimensional components of velocities along x' and y' -directions u , v non-dimensional components of velocities along x' and y' -directions x', y ' dimensional spatial coordinates along and normal to the plate x, y non-dimensional spatial coordinates along and normal to the plate g acceleration due to gravity T' dimensional temperature of the fluid T non-dimensional temperature of the fluid T~ temperature of the free stream '(, temperature of the wall B0 uniform magnetic field m' dimensional exponential index m non-dimensional exponential index t ' dimensional time t non-dimensional time J non-dimensional micro-inertia j' dimensional micro-inertia k effective thermal conductivity kc absorption coefficient q'" non-uniform heat generation /absorption q , radiative heat flux in y ' direction r u: free stream velocity U~ dimensional velocity of the plate t 198 UP nondimensional velocity of the plate A real positive constant V0 scale of suction velocity U0 scale of free stream velocity Pr Prandtl number Gr Grashof number R radiation parameter A. space dependent heat source/sink parameter s• temperature dependent heat source/sink parameter Greek symbols: