Document Type : Research Article
DEPT. OF MECH. ENGR., UNIVERSITY OF LAGOS, NIGERIA.
In this paper the geometry effects of different nanoparticles such as cylindrical, spherical and lamina on heat transfer of fluid transported through contracting or expanding microchannel are considered. The nanofluid flow and heat transfer through the porous channel are described using mathematical models. Since the mathematical models are nonlinear in nature the homotopy perturbation method (HPM), an approximate analytical method is adopted to provide analytical solution to the mathematical model. The fast convergence rate coupled with analytical procedural stability motivates the use of the HPM as the favored method in providing solutions to the system of coupled, higher order differentials.The obtained analytical solution is used to investigate the influence of particle shape of the nano sized materials on heat transfer of fluid flowing through a porous medium considering a uniform magnetic field. It is illustrated from results that lamina nanoparticle shape shows higher dimensionless temperature and thermal conductivity when compared with nano shaped particles of cylinder and sphere respectively due to variations in thermal boundary layers. Results obtained from this study prove useful in the advancement of science and technology including micro mixing, nanofluidics and energy conservation. Comparing obtained analytical solution with fourth order numerical solution, good agreement was established.