Effect of radiation on MHD free convection flow past an impulsively moving vertical plate with ramped wall temperature

The effects of radiation on MHD free convection flow of a viscous incompressible electrically conducting fluid past a moving infinite vertical plate with ramped wall temperature have been studied.The Laplace transform technique has been applied to obtain an exact solution in a closed form, when the plate is moving impulsively with a velocity 0 U .It is examined that two different solutions for the fluid velocities, one valid for fluids of Prandtl number ( Pr ) different from 1 and the other for which the Prandtl number equal to 1.The variations of velocity and fluid temperature are presented graphically.It is observed that the velocity decreases with an increase in Prandtl number for ramped temperature as well as for constant wall temperature.An increase in Grashof number leads to a rise in the values of velocity due to enhancement in buoyancy force.The velocity decreases with an increase in Hartmann number which implies that magnetic field has an retarding influence on the flow.The effect of the Prandtl number is very important in the temperature field.A fall in temperature occurs due to an increasing value of the Prandtl number.It is seen that the temperature decreases as the radiation parameter increases for ramped temperature as well as for constant wall temperature.