Mhd Flow in a Channel Using New Combination of Order of Magnitude Technique and Hpm

Original scientific paper The present work is concerned with the steady incompressible flow through a parallel plate channel with stretching walls under an externally applied magnetic field. The governing continuity and Navier-Stokes equations are reduced to a fourth order nonlinear differential equation by using vorticity definition and similarity solution transformation. The obtained equations are solved by applying the analytical homotopy perturbation method (HPM). The method is called order of magnitude suggested for simplifying series solution to finite expression that is useful in engineering problems. The results are verified by comparing with numerical solutions and demonstrate a good accuracy of the obtained analytical solutions. Profiles for velocity are presented for a range of plate velocity and magnetic field. The study shows that a back flow occurs near the center line of the channel and with the increase in strength of magnetic field, the back flow decreases.