Abstract
In the present paper, the free convection oscillatory flow of a micropolar fluid determined by a vertical an infinite surface plane has fluctuates harmonically temperature with a relaxation time is studied. The surface has a constant suction and oscillates free steam velocity, and absorbs the fluid. The Eringen model for micropolar fluid is applied to solve the problem. The components of velocity, induced magnetic field, and concentration profiles have been obtained. The technique of regular perturbation is considered to solve the equations governing to a set of linear coupled and uncoupled ordinary differential equations. The problem has been solved for the small values of the micropolar perturbing parameter χ. The effects of Prandetl number Pr, Grashof number Gr, material parameter χ,β,γ are discussed. The cooling and heating effect on the fluid has been discussed. The numerical results indicate that the external parameters are affected strongly on the electrically conducting micropolar concentration fluid. If the electrically conducting and thermal relaxation time, the results obtained deduce to the results obtained by Sharma and Gupta (1995) [31].