An Investigation of Mixed Convection Flow on a Vertical Flat Plate of a Saturated Nanofluid in a Porous Medium near the Stagnation Point

Document Type : Article


Department of mechanical engineering, Payame Noor University, Tehran, Iran


In the present paper, a non-similar solution of a steady saturated nano-fluid flow, heat, and mass transfer is investigated. The nano-fluid flow is under dual effects of stagnation flow and natural convection heat transfer on a vertical flat plate in a porous medium. Effects of variations in Thermophoresis, Brownian motion, and buoyancy force have been studied. The partial differential equations are transformed into six ordinary differential equations with appropriate non-similarity variables, which also consider the longitudinal coordinate of the x-axis. In order to solve, we have formed a set of fourteen ordinary differential equations of the first order. A complicated double method finds six unknown initial values in the boundary value problem. Variations of longitudinal velocity, shear stress, temperature, and nanoparticle volume fraction are considered as functions of transverse and longitudinal coordinates. As a result, the minimum accuracy of the first-order non-similar solution in regions very close to the stagnation point is 96%. Also, the velocity profile is observed to vary along the longitudinal x-axis near the stagnation point, which is an improvement over the existing knowledge which largely assumes a constant velocity profile throughout the stagnant flow region.


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