INFLUENCE OF WALL CONDUCTIVITES ON A FULLY DEVELOPED MIXED-CONVECTION MAGNETOHYDRODYNAMIC NANOFLUID FLOW IN A VERTICAL CHANNEL

A fully developed mixed-convection nanofl uid fl ow in a vertical channel with variable thermal and electrical wall
conductivities in the presence of a uniform transverse magnetic fi eld is studied. The working fl uid is a homogeneous
mixture of a base fl uid (water) and metallic nanoparticles of three different kinds, namely, copper, alumina, and
titanium dioxide. The fl uid is also electrically conducting in the presence of an applied magnetic fi eld. The fl ow is
characterized by a moderate magnetic Reynolds number. An induced magnetic fi eld is present. The effects of the
pertinent parameters on the nanofl uid temperature, velocity, and induced magnetic fi eld strength, as well as on the
shear stress and heat transfer rate at the channel wall, are shown. In the case of a negative vertical temperature
gradient (heating from below), there exists a critical Rayleigh number at which the fl uid becomes unstable. This
number is also found as a function of the wall conductivities.

   
Author:  S. Das, B. Tarafdar, R. N. Jana, and O. D. Makinde
Keywords:  fully developed fl ow, mixed convection, nanofl uids, wall conductivity, channel
Page:  784