International Journal of Heat and Mass Transfer, Vol.103, 291-297, 2016
A revised model to analyze the heat and mass transfer mechanisms in the flow of Carreau nanofluids
In the current framework, an investigation is carried out on the flow of Carreau nanofluids with focus on heat and mass transfer which includes the effects of Brownian motion and thermophoresis. This paper provides information about newly proposed boundary condition of normal mass flux of nanoparticles at the wall. In this condition the nanofluid volume fraction on the boundary is considered to be passively controlled which make the analysis more interesting. The study is conducted by means of the local similarity variables to transform the governing equations into a set of nonlinear ordinary differential equations. The arising differential system which is composed of momentum, temperature and concentration equations is treated through a numerical approach called the Runge-Kutta Fehlberg integration technique. Finally, the main aim upon which the present study is based is about the influence of controlling parameters on momentum, thermal and concentration fields. The numerical results indicate that an appreciable declined in the rate of heat transfer coefficient is noted with the increase of both thermophoretic force and Lewis number. Also, it can be concluded that an enhancement in the Brownian motion results in a significant diminution of the nanoparticles volume friction. (C) 2016 Elsevier Ltd. All rights reserved.
Keywords:Carreau nanofluid;Heat transfer;New mass flux condition;Stretching surface;Runge-Kutta method