Similarity Solutions of Boundary Layer Flow of a Nanofluid Past a Stretching Sheet with a Convective Boundary Condition in the Presence of Magnetic Field and Thermal Radiation

摘要

Boundary layer flow induced in a nanofluid due to a linearly stretching sheet in the presence of thermal radiation and induced magnetic field is studied numerically, following a similarity analysis of the transport equations. The transport model employed includes the effect of Brownian motion and thermophoresis. The analysis shows that temperature and concentration profiles in the respective boundary layers depend, besides the Prandtl and Lewis numbers, on five additional dimensionless parameters, namely a Brownian motion parameter Nb, a thermophoresis parameter Nt, a thermal radiation parameter Ra, magnetic field parameter M and a convection Biot number Bi. The thermal boundary thickens with a rise in the local temperature as the radiation parameter, Brownian motion, thermophoresis and convective heating each intensify. The Lewis number has profound effects on the temperature distribution at the wall plate at Nt = Nb = 0.5 but has no effect when Nt = Nb = 0 1. Fixing the other parameters, the local concentration of nanoparticles increases as the convection Biot number increases but decreases as the Lewis number increases. For fixed Ra, M, Pr, Le and Bi, the reduced Nusselt number decreases but the reduced Sherwood number increases as the Brownian motion and thermophoresis effects increases.