Unsteady boundary layer flow of a nanofluid over a stretching sheet with variable fluid properties in the presence of thermal radiation
Mitiku Daba and P. Devaraj
Anna University, Chennai, India E-mail: mitbru2007@yahoo.com, devaraj@annauniv.edu
Keywords: unsteady boundary layer, nanofluid, Brownian motion, Keller-box method, stretching sheet, thermophoresis, thermal radiation
Pages: 403–413
Abstract
In this paper, we investigated numerically an unsteady boundary layer flow of a nanofluid over a stretching sheet in the presence of thermal radiation with variable fluid properties. Using a set of suitable similarity transformations, the governing partial differential equations are reduced into a set of nonlinear ordinary differential equations. System of the nonlinear ordinary differential equations are then solved by the Keller-box method. The physical parameters taken into consideration for the present study are: Prandtl number Pr, Lewis number Le, Brownian motion parameter Nb, thermophoresis parameter Nt, radiation parameter Nr, unsteady parameter M. In addition to these parameters, two more new
parameters namely variable thermophoretic diffusion coefficient parameter ε and
variable Brownian motion diffusion coefficient parameter β have been introduced
in the present study. Effects of these parameters on temperature, volume
fraction of the nanoparticles, surface heat and mass transfer rates are
presented graphically and discussed briefly. To validate our method, we have
compared the present results with some previously reported results in the literature.
The results are found to be in a very good agreement.
DOI: 10.1134/S0869864316030100
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