The aim of this work is the numerical study of natural convection in a square enclosure filled with nanofluids, using (Cu-water) and (TiO 2 - water) nanofluids. The finite volume method is used to solve the Navier-Stocks and energy equations. The effects of different relevant parameters, such as types of nanoparticles, volume fraction of nanoparticles (0-30%) and whose Rayleigh number varying from 10 3 to 10 6 . It appears from this study that heat transfer increases by increasing the Rayleigh number and the volume fraction of the nanoparticles. The use of nanofluid enhances heat transfer, the highest heat transfer enhancement is observed in Cu-nanofluid. Consequently, the type of nanoparticle is a main factor for the enhancement of heat transfer. A comparison of our results with those of Barakos and Mitsoulis revealed a good agreement.
Lahlal et al. (Wed,) studied this question.