关键词: Williamson fluid, exponential stretching, generalized hyperbolic perturbation method, optimal homotopy analysis method (OHAM), nonlinear autonomous sys-tem, heat transfer, homoclinic solution, prescribed exponential order surface temperature (PEST), prescribed exponential order heat flux (PEHF), permeable wall

Abstract:

This study explores the effects of heat transfer on the Williamson fluid over a porous exponentially stretching surface. The boundary layer equations of the Williamson fluid model for two dimensional flow with heat transfer are presented. Two cases of heat transfer are considered, i.e., the prescribed exponential order surface temperature (PEST) case and the prescribed exponential order heat flux (PEHF) case. The highly nonlinear partial differential equations are simplified with suitable similar and non-similar variables, and finally are solved analytically with the help of the optimal homotopy analysis method (OHAM). The optimal convergence control parameters are obtained, and the physical features of the flow parameters are analyzed through graphs and tables. The skin friction and wall temperature gradient are calculated.

Key words: permeable wall, Williamson fluid, exponential stretching, prescribed exponential order surface temperature (PEST), homoclinic solution, prescribed exponential order heat flux (PEHF), heat transfer, optimal homotopy analysis method (OHAM), generalized hyperbolic perturbation method, nonlinear autonomous sys-tem