Effects of Slip velocity Boundary condition on Natural Convection of MgO-Ag/Water nanofluid in Microcavity

The present study investigates MgO-Ag/Water hybrid nanofluid in a microcavity at Rayleigh numbers ۱۰۳, ۱۰۴ and ۱۰۵ and φ=۰.۰۵ and ۰.۱۵% nanoparticles with slip velocity boundary condition. The results show that with increasing the Rayleigh number, the nanoparticle volume fraction and slip velocity of the Nusseltnumber increase. The results also show that the Rayleigh number is a more effective parameter for increasing the Nusselt number and the volume fraction of the nanoparticles is a more effective parameter than the slip velocity for increasing the Nusselt number. The results show that increasing the slip velocity causes the vortices to become larger and that the vortices become larger due to better mixing and that the a mean Nusselt number on the microcavity hot wall should be increased. The results also suggest that increasing the slip velocity will cause wider isothermal and will help the temperature mix and increase the Nusselt number on hot wall. In general, slip velocity is more effective at larger Rayleigh numbers.

Keywords:

microcavity , hybrid nanofluid , slip boundary condition , Nusselt number