Lattice Boltzmann Simulation of Mixed Convection Heat Transfer in a Corrugated Wall Cavity Utilizing Water-Based Nanofluids

In the present study, the effects of Cu and CuO nanoparticles' presence on mixed convection heat transfer in a lid-driven cavity with a corrugated wall are investigated using the lattice Boltzmann method. The boundary fitting method with second-order accuracy at both velocity and temperature fields is used to simulate the curved boundaries in the LBM. The problem is investigated for different Richardson numbers (0.1-10), volume fractions of nanoparticles (0-0.05), curve amplitudes (0.05-0.25), and phase shifts of corrugated wall (0-270) when the Reynolds number is equal to 25. The volume fraction of added nanoparticles to the water-based fluid is less than 0.05 to make dilute suspensions. Results show that adding nanoparticles enhances the rate of heat transfer. It is found that nanoparticles have significant effects on both fluid flow and heat transfer of the mixed convection, especially for low Richardson numbers. A comparison between Cu and CuO nanoparticles shows the Cu nanoparticles have a better effect on heat transfer enhancement for all tested conditions. The results also represent the effective role of a corrugated wall on the rate of nanofluid heat transfer. It is observed that increasing the wavy wall's amplitude leads to a decrease of the average Nusselt numberfor a high Richardson number.(C) 2012 Wiley Periodicals, Inc.