Natural Convection of Nanofluids in a Cavity with Nonuniform Temperature Distributions on Side Walls

A numerical study is performed to investigate the effects of amplitude and phase deviation of sinusoidal temperature distribution on the convective flow and heat transfer of nanofluids in a square cavity. The horizontal walls of the cavity are adiabatic. The governing equations are solved by the finite volume method with the SIMPLE algorithm. The results are discussed for different combinations of phase deviation, amplitude ratio, volume fraction of nanoparticles, and Rayleigh numbers. It is observed that the heat transfer rate is increased when increasing the amplitude ratio and volume fraction of nanoparticles. The heat transfer rate behaves nonlinearly with the Rayleigh number and the phase deviation, attaining the maximum at 3 pi/4.