Effect of time-dependent heat source/sink on slip flow and heat transfer from a stretching surface with homotopy analysis method

In this paper, the effect of time-dependent heat source/sink on heat transfer characteristics of the unsteady mixed convection flow over an exponentially stretching surface are investigated analytically. Both hydrodynamic and thermal slip conditions are considered in this flow. The fluid viscosity is assumed to vary as a reciprocal linear function of temperature. The governing equations are simplified by suitable transformations into a system of dimensionless ordinary differential equations. The reduced equations are then solved analytically by the homotopy analysis method (HAM). The convergence of the HAM solution is obtained by plotting \(\hbar \)-curves for velocity and temperature gradients. Solutions of the velocity profiles, the temperature profiles, the local skin friction coefficient and the local heat transfer rate are obtained for some representative values of the variable viscosity parameter \(\Theta \), mixed convection parameter ξ, velocity slip parameter \(\Gamma \), thermal slip parameter \(\delta \) and heat source/sink parameter Q _H .