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A mixed convection flow and heat transfer of pseudo-plastic power law nanofluid past a stretching vertical plate is investigated. Three types of nano-particles, such as copper (Cu), aluminum oxide (Al 2 O 3 ) and titanium oxide (TiO 2 ), are considered. The generalized Fourier law proposed by Zheng for varying thermal conductivity of nanofluids, which is dependent on the power law of velocity gradient as well as the nano-particles property, is taken into account. Dual solutions are obtained by Bvp4c with Matlab. The stability of the solution also is discussed by introducing the unsteady governing equations. Furthermore, a new interesting phenomenon is found: the local Nusselt number do not maintain the similar characteristics of Newtonian fluid near the point where the velocity ratio is equal to 0.5. [ABSTRACT FROM AUTHOR]

In this paper, we examine the laminar film condensation of pseudo-plastic non-Newtonian fluids with variable thermal conductivity on an isothermal vertical plate. The thermal conductivity is assumed to be power-law-dependent on the velocity gradient. The dual similar solutions, which are influenced by the parameters of the power law number n and the thickness η δ of the condensation film, are obtained numerically by Runge–Kutta method coupled with shooting method. More attention is paid to discuss the first branch of the solutions with physical meaning. Especially the effects of above both parameters on the velocity and temperature distribution, condensation mass flow rate and the local Nusselt number are analyzed in detail. [ABSTRACT FROM AUTHOR]

Abstract: Considering the influence of the viscous dissipation in the energy equation, we investigate the flow and heat transfer of an incompressible micropolar fluid in a channel with expanding or contracting walls. By introducing suitable similarity transformations, the nonlinear partial differential equations are reduced to a system of ordinary differential equations. Homotopy analysis method (HAM) is employed to obtain the series solutions for the velocity, microrotation and temperature distribution. In order to analyze the influence of the micropolar parameter, the Reynolds number and the deformation of the wall, the graphs for velocity components, microrotation, temperature, couple stress and shear stress in the channel are presented and discussed in detail. [Copyright &y& Elsevier]