Numerical Simulation of Natural Convection Heat Transfer of Nanofluid with Cu, MWCNT, and Al2O3 Nanoparticles in a Cavity with Different Aspect Ratios

Effect of the size of a closed cavity and different nanoparticles on natural convection heat transfer is investigated using the finite volume method. In the current numerical study, free convection of nanofluid with Cu, multi-walled carbon nanotubes, and Al2O3 nanoparticles is considered at Rayleigh numbers (Ra) of 10–100,000 inside a two-dimensional rectangular cavity with different aspect ratios. Results of this study show that in the presence of cooling fluid with low temperature and hot zone in the cavity, due to the temperature difference between the fluid and hot zone, heat transfer occurs. Heat transfer in the cavity is influenced by fluid circulation caused by natural convection heat transfer and conductive heat transfer mechanism.