Turbulence Combined Convective Heat Transfer and Nanofluids Flows over Double Forward Facing Steps

Predictions are reported for mixed convection using various types of nanofluids over forward-facing double steps in a duct. The continuity, momentum and energy equations are discretized and the simple algorithm is applied to link the pressure and flow fields inside the domain. Different types of nanoparticles Al2O3, CuO, SiO2 and ZnO, with different volume fractions in range of 1-4% are investigated to identify their effects on the heat transfer and fluid characteristics. Numerical investigations are conducted using finite volume method. The results indicate that SiO2 -water has the highest Nusselt number followed by Al2O3-water, CuO -water and ZnO-water. The Nusselt number increases as the volume fraction increases but decreases as the nanoparticles diameter increases