Natural convection flow of a non-Newtonian power-law fluid from a slotted vertical surface with uniform surface heat flux

Abstract

In the present paper, the natural convection flow of an Ostwalde—de Waele type power-law non-Newtonian fluid past a uniformly heated vertical slotted surface has been investigated numerically. The equations governing the flow and heat transfer are reduced to local non-similarity form. The transformed boundary-layer equations are solved numerically using implicit finite-difference method for values of ξ in the interval [0, ∞]. Solutions for heat transfer rate obtained for the rigid surface compared well with those documented in the published literature. From the present analysis, it is observed that an increase in ξ leads to increasing the skin-friction as well as reduction in heat transfer at the surface. As the power-law index n increases, the friction factor as well as the surface heat transfer increases.

Keywords

natural convection power-law fluid slotted surface boundary layer

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