Mixed convection flow of non‐Newtonian fluid from a slotted vertical surface with uniform surface heat flux

Abstract

In the present paper, the combined convection flow of an Ostwald-de Waele type power-law non-Newtonian fluid past a vertical slotted surface has been investigated numerically. The boundary condition of uniform surface heat flux is considered. The equations governing the flow and the heat transfer are reduced to local non-similarity form. The transformed boundary layer equations are solved numerically using implicit finite difference method. Solutions for the heat transfer rate obtained for the rigid surface compare well with those documented in the published literature. From the present analysis, it is observed that, an increase in leads to increase in 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 heat transfer increase.Dans cet article, on aétudié numériquement l'écoulement de convection combinée d'un fluide non-newtonien de loi de puissance de type Ostwald-de Waele en aval d'une surface perforée verticale. La condition limite d'un flux de chaleur de surface uniforme est considérée. Leś equations gouvernant l'écoulement et le transfert de chaleur sont réduitesà la forme de non-similarité locale. Leséquations de couche limite transformées sont résolues numériquement par la méthode des différences finies implicites. Les solutions pour la vitesse de transfert de chaleur obtenues pour la surface rigide se comparent bienà celles qui sont décrites dans la littérature scientifique publiée.À partir de la présente analyse, on observe qu'une augmentation de mèneà une augmentation du frottement superficiel ainsi qu'à une réduction du transfert de chaleurà la surface. Lorsque l'indice de loi de puissance n augmente, le facteur de friction et le transfert de chaleur augmententégalement.

Mixed convection in a doubly stratified micropolar fluid saturated non‐Darcy porous medium

“…Jaluria and Gebhart (1974) studied the stability of the flow adjacent to a vertical plate dissipating a uniform heat flux into a stratified medium both theoretically and experimentally. The combined convection flow of an Ostwald-de Waele type power-law non-Newtonian fluid past a vertical slotted surface in the presence of uniform surface heat flux, has been investigated numerically by Gorla et al (2009). Unlike the case of linear stratification, the flow reversal and temperature deficit in this case (Gebhat et al, 1988), where the variation of the ambient temperature is relatively weak, are extremely small.…”

“…The effects of heat and mass transfer in non-Newtonian fluid have great significance in engineering applications such as thermal design of industrial equipment dealing with molten plastics, polymeric liquids, foodstuffs or slurries. The combined convection flow of an Ostwald-de Waele type power-law non-Newtonian fluid past a vertical slotted surface in the presence of uniform surface heat flux, has been investigated numerically by Gorla et al (2009). The micropolar fluid model introduced by Eringen (1966) exhibits some microscopic effects arising from the local structure and micromotion of the fluid elements.…”

Solutal Dispersion and Viscous Dissipation Effects on Non‐Darcy Free Convection Over a Cone in Power‐Law Fluids

“…These can be obtained by differentiating Eqs. (23)- (25) with respect to ε and neglecting the terms ∂G / ∂ε, ∂H / ∂ε, and ∂K / ∂ε. This generates three auxiliary equations:…”

“…The corresponding boundary conditions are The coupled nonlinear differential Eqs. (23)- (25) and (28) With Gr * = 0, n = 1, ε = 0, and Ra ξ = 0 (i.e., for the Newtonian fluid), Eqs. (7)-(9) governing the present investigation of power-law fluid-saturated non-Darcy porous medium reduce to those limiting the case of the free convection flow of Yih [31], who investigated the problem of free convection in a Newtonian fluid-saturated porous medium by considering constant viscosity.…”

Transient Combined Convective Heat Transfer over a Stretching Surface in a Non-Newtonian Nanofluid Using Buongiorno’s Model

“…The flow and heat transfer characteristics on a moving plate in a nanofluid were investigated [10]. [11] studied the mixed Convection Flow of Non-Newtonian fluid from a Slotted Vertical Surface with Uniform Surface Heat Flux. [12] investigated theoretically the mixed convection in an axisymmetric stagnation flow of a non-Newtonian nanofluid on a vertical cylinder.…”