Homotopy analysis of unsteady heat transfer started impulsively from rest along a symmetric wedge

In this paper, the unsteady heat transfer over an impulsively started wedge is investigated. The mixed convection, namely, the thermal boundary-layer growth is caused by the sudden increase of the surface temperature as it is set into motion. The analytic approximations with high accuracy are given using the Homotopy–Padé technique, which agree well with the numerical results using an implicit finite-difference method known as Keller–Box method. It is found that the Homotopy–Padé approximations have no relation to the auxiliary parameters ћf and ћg, which play important roles in the homotopy analysis method.