analysis of particle dispersion in turbulent mixed convection of cuo-water nanofluid

In the present paper, turbulent convection of CuO-Water Nanofluid in a vertical channel is investigated numerically. In order to simulate the flow, the fluid is considered as a continuous phase while the discrete nanoparticles are dispersed through it. The dispersion of CuO nanoparticles in different flow conditions are studied in order to find the effective mechanisms of particles dispersion in the channel. The results show that in the fully developed turbulent convection flow, thermophoresis is more dominant than Brownian motion of nanoparticles and therefore the nanoparticles aggregation are more in the central areas of the channel. While in entrance region, where the boundary layer is not fully formed, the particles dispersion are more uniform. Also, an increase in the nanoparticles concentration will increase the turbulent velocity fluctuations in regions near the wall and this two-sided effect will cause improvement in turbulent flow thermal transmitance than the laminar flow.