Optimal solution of nonlinear heat and mass transfer in a two-layer flow with nano-Eyring–Powell fluid

This paper deals with the fully-developed two-layer Eyring–Powell fluid in a vertical channel divided into two equal regions. One region is filled with the clear Eyring–Powell fluid and other with the nano-Eyring–Powell fluid. The flow is observed under the uniform wall temperature and concentration boundary conditions for combined heat and mass transfer. The governing coupled nonlinear ordinary differential equations (ODEs) of the flow in each layer are analytically solved by using optimal homotopy analysis method (OHAM) based on the homotopy analysis method (HAM). HAM is an efficient analytical approximation method to solve highly nonlinear problems. The effect of Brownian motion parameter on Eyring–Powell fluid is also observed and the influence of significant parameters is presented for their different values.