Mixed convection flow of a micropolar fluid near a non-orthogonal stagnation-point on a stretching vertical sheet

Abstract

Purpose - The purpose of this paper is to study theoretically the steady two-dimensional mixed convection flow of a micropolar fluid impinging obliquely on a stretching vertical sheet. The flow consists of a stagnation-point flow and a uniform shear flow parallel to the surface of the sheet. The sheet is stretching with a velocity proportional to the distance from the stagnation point while the surface temperature is assumed to vary linearly. The paper attempts also to show that a similarity solution of this problem can be obtained. Design/methodology/approach - Using a similarity transformation, the basic partial differential equations are first reduced to ordinary differential equations which are then solved numerically using the Keller box method for some values of the governing parameters. Both assisting and opposing flows are considered. The results are also obtained for both strong and weak concentration cases. Findings - These results provide information about the effect of a/c (ratio of the stagnation point velocity and the stretching velocity), (shear flow parameter) and K (material parameter) on the flow and heat transfer characteristics in mixed convection flow near a non-orthogonal stagnation-point on a vertical stretching surface. The results show that the shear stress increases as K increases, while the heat flux from the surface of the sheet decreases with an increase in K. Research limitations/implications - The results in this paper are valid only in the small region around the stagnation-point on the vertical sheet. It is found that for smaller Prandtl number, there are difficulties in the numerical computation due to the occurrence of reversed flow for opposing flow. An extension of this work could be performed for the unsteady case. Originality/value - The present results are original and new for the micropolar fluids. They are important in many practical applications in manufacturing processes in industry.