Nanofluid flow on the stagnation point of a permeable non-linearly stretching/shrinking sheet

Abstract

This paper studies a steady two-dimensional stagnation-point flow of nanofluids over a nonlinearly stretching/shrinking sheet in the presence of blowing/suction. The effects of different nanoparticle materials, namely copper, alumina and titania on the flow and heat transfer rate are investigated. Employing similarity variables, the governing partial differential equations including continuity, momentum and energy have been reduced to ordinary equations and are solved numerically via Runge-Kutta-Fehlberg scheme. It is shown that two solutions exist for shrinking sheets in both blowing and impermeable cases, while an additional solution appears in the case of suction (there are three solutions). Moreover, the effects of nonlinearly parameter β, blowing/suction S, and solid volume fraction ϕ on the heat and fluid flow characteristics are investigated in details. Keywords: Nano-fluid, Stagnation-point flow, Stretching/shrinking sheet, Similarity solution, Multiple solutions