Numerical investigation of Cu-water nanofluid natural convection and entropy generation within a cavity with an embedded conductive baffle

This article presents a numerical study of natural convection and entropy generation of cu-waternanofluid within an enclosure with a conductive baffle embedded on bottom hot wall. the governingequations are solved numerically with finite volume method using the simpler algorithm. effects ofrayleigh number, position of conductive baffle and volume fraction of nanoparticles on the streamlines,isotherms, mean nusselt number, entropy generation, bejan number and irreversibility factor have beenstudied. at ra d 104 the convection heat transfer is very weak and the dominant conduction weakensby displacing the baffle toward the center of the cavity, thus the mean nusselt number decreases. athigher rayleigh numbers due to enhanced convection, the improved mean nusselt number increases byincreasing the volume fraction and displacing the baffle toward the center of the cavity. the effect ofvolume fraction and position of the baffle on entropy generation and bejan number at ra d 104 is differentfrom ra d 105 and 106. this is due to the effects of addition of nanoparticles on the effective viscosityand conductivity of nanofluid and conduction dominance. it has been shown that assuming a constantirreversibility factor, , with change of ra and ' is not correct.