Mixed Convection Heat Transfer of Water-Based CUO Nanofluids in an Inclined Lid-Driven Enclosure

Mixed convection of water-based CuOnanofluids in a lid-driven inclined enclosure heated and cooled from the adjacent left and top walls was studied numerically in this study for various values of pertinent parameters. The computational results of the governing equations were obtained by a commercialfinite element modelling and simulation software. The Grash of number was taken constant at a value of 104. Reynolds number was varied in a way that the Richardson number takes on values in the range of 0.1 to 10. Three different nanoparticle volume fractions were considered: 0%, 4% and 8%.The inclination angle was taken as 0, 30, 45, and 90 degrees. The results show that flow in the enclosure is unicellular for the low values of inclination angle and a secondary counterclockwise circulation emerges with an increase in the inclination angle. The average Nusselt number takes higher values with an increase in the solid volume fraction and with a decrease in the Richardson number. The results also indicate that the average Nusselt number shows a decrease with increasing inclination angle except for Ri=0.1. The results finally show that the average Nusselt number gets its highest value at the inclination angle of 30 degrees for Ri=0.1. Keywords - Heat transfer, mixed convection, inclined enclosure, nanofluid, water, CuO, Nusselt number.