MIXED CONVECTION HEAT TRANSFER IN A DOUBLE LID-DRIVEN INCLINED SQUARE ENCLOSURE SUBJECTED TO Cu–WATER NANOFLUID

In this article, mixed convection fl ow in a two-sided lid-driven cavity at diff erent inclination angles fi lled with Cu–water nanofl uid (with diameter of 90 nm) is studied numerically using the fi nite volume method. For diff erent values of solid volume fraction of nanoparticles, fl ow is induced by the top and right-hand sidewalls sliding at constant speed. The left-hand sidewall is kept constant at higher temperature (Th), while the right moving wall is maintained at a lower temperature (Tc), thereby introducing natural convection. In this study, bott om and top walls were assumed isolated; Richardson number ranged from 0.001 to 10, nanoparticles solid volume fraction (φ) up to 0.06 were investigated, and cavity inclination angle from 0 ° to 90 ° was con-sidered and the Grashof number was set to 104. The infl uence of inclination angle and φ of the nanofl uids on hydrodynamic and thermal characteristics is discussed. The results indicated that increase in φ for a constant Ri enhances heat transfer. Also, heat transfer was increased as Ri was decreased for a particular φ. Moreover, where natural convection is dominant (i.e., higher Ri), the fl ow form seems to be infl uenced more by φ. KEY WORDS: nanofl uid, heat transfer, mixed convection, double lid-driven cavity, numerical analysi