Semi-analytical solution for the flow of a nanofluid over a permeable stretching/shrinking sheet with velocity slip using Buongiorno's mathematical model

In this analysis, the flow and heat transfer characteristics of a nanofluid over a stretching/shrinking surface with suction are investigated. Using a similarity transformation, the nonlinear system of partial differential equations is converted into nonlinear ordinary differential equations. These resulting equations are solved analytically and numerically using a collocation method. Multiple (dual: upper and lower branch) solutions are shown to exist in a range of the governing parameters. In addition, the reduced skin friction coefficient and the reduced heat transfer from the surface of the sheet as well as the velocity, temperature and concentration profiles are analyzed subject to several parameters of interest, namely suction parameter, Brownian motion and thermophoresis parameters, Prandtl number, nanofluid Lewis number and dimensionless slip parameter. The results indicate that the skin friction coefficient and the heat transfer from the surface of the sheet increase with suction effect. It is also observed that suction widens the range of the stretching/shrinking parameter for which the solution exists.