Unsteady MHD flow and heat transfer near stagnation point over a stretching/shrinking sheet in porous medium filled with a nanofluid

作     者：Sadegh Khali Saeed Dinarvand Reza Hossei Hossein Tamim Ioan Pop 

作者机构：Young Researchers and Elite Club Saveh Branch Islamic Azad University Mechanical Engineering Department Amirkabir University of Technology Department of Mechanical Engineering Saveh Branch Islamic Azad University Department of Mathematics Babes-Bolyai University 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2014年第23卷第4期

页      面：669-676页

核心收录：

学科分类：080103[工学-流体力学] 08[工学] 0801[工学-力学（可授工学、理学学位）] 

主　　题：nanofluid Navier-Stokes equations MHD dual solutions porous media 

摘      要：In this article, the unsteady magnetohydrodynamic （MHD） stagnation point flow and heat transfer of a nanofluid over a stretching/shrinking sheet is investigated numerically. The similarity solution is used to reduce the governing system of partial differential equations to a set of nonlinear ordinary differential equations which are then solved numerically using the fourth-order Runge-Kutta method with shooting technique. The ambient fluid velocity, stretching/shrinking velocity of sheet, and the wall temperature are assumed to vary linearly with the distance from the stagnation point. To investigate the influence of various pertinent parameters, graphical results for the local Nusselt number, the skin friction coefficient, velocity profile, and temperature profile are presented for different values of the governing parameters for three types of nanoparticles, namely copper, alumina, and titania in the water-based fluid. It is found that the dual solution exists for the decelerating flow. Numerical results show that the extent of the dual solution domain increases with the increases of velocity ratio, magnetic parameter, and permeability parameter whereas it remains constant as the value of solid volume fraction of nanoparticles changes. Also, it is found that permeability parameter has a greater effect on the flow and heat transfer of a nanofluid than the magnetic parameter.