Similarity Solution of Unsteady MHD Boundary Layer Flow and Heat Transfer past a Moving Wedge in a Nanofluid using the Buongiorno Model

Abstract

The present work is focused on the unsteady MHD boundary layer flow and heat transfer over a wedge stretching surface moving in a nanofluid with the effects of various dimensionless parameters by using the Boungiorno model. The solution for the velocity, temperature and nanoparticle concentration depends on parameters like Prandtl number Pr, Brownian motion Nb, thermophoresis Nt, unsteadiness parameter A, velocity ratio parameter λ, pressure gradient parameter β and magnetic parameter M. The local similarity transformation is used to convert the governing partial differential equations into coupled higher order non-linear ordinary differential equations. These equations are numerically solved by using fourth order RungeKutta method along with shooting technique. Numerical results are obtained for distributions of velocity, temperature and nanoparticle concentration, as well as, for the skin friction, local Nusselt number and local Sherwood number for several values of governing parameters. The results are shown in graphically and as well as in a tabular form. From the graph the results indicate that the velocity increases for increasing values of magnetic parameter, unsteadiness parameter and pressure gradient parameter but decreases for velocity ratio parameter. The temperature profile increases for thermophoresis and Brownian motion parameter but reverse results arises for Prandtl number and velocity ratio parameter. On the other hand, nanoparticle concentration decreases for thermophoresis parameter, Lewis number and velocity ratio parameter. But in case of Brownian motion parameter the concentration decreases up to η < 1 and then increases. Besides, the present results are compared with previously published work and found to be in good agreement.