Mixed convection flow of aluminium-oxide nanoparticles in water through a circular tube was modelled using the discrete
phase model and implemented on ANSYS-Fluent 17.0 through customised user-defined functions. The inclination angle
was varied to study its effect on the migration and deposition of the nanoparticles. Experimentally determined thermophysical
properties were used in the analysis instead of theoretical or empirical models from the literature. Varying
inclination angles were found to significantly affect the migration and deposition of nanoparticles. A critical angle of
maximum deposition of approximately 30 was found for volume concentrations 1%, 3% and 5%. The effect of varying
inclination angle on the heat transfer coefficient was minimal for low angles of inclination between 0 and 35% and
decreased significantly after 40%. The effect of Saffman’s lift, thermophoretic, Magnus and Brownian effects were also
investigated, and results show that thermophoretic and Brownian effects were most dominant effects.
