Analysis of natural convection of nanoliquid in a heated incinerator shaped cavity with a pair cold finned cylinders

Abstract

This paper presents a numerical investigation of natural convection fluid flow and heat transfer in an incinerator-shaped cavity containing a pair of cold finned cylinders. The discretized system is treated via the finite element method with COMSOL software. Numerical results are presented as streamlines, isotherms, entropy generation iso-contours and average Nusselt number. Effects of Rayleigh number (Ra=103-106), number of fins (N), and the solid volume fraction (ϕ=1%-4%) have been investigated. The effect of the baffles location on convective heat flux is also investigated. Results show that the rate of heat transfer is enhanced with an increase of the Rayleigh number while it is decreased by enhancement of the number of fins. In addition, the numerical results demonstrate that the average Nusselt number increases with the rise of the solid volume fraction (ϕ) for all Rayleigh numbers. Finally, it is found that the energy transfer to the cold cylinders was obtained when the baffles are located on the walls of the cylinder near the inlet (hot regions) and not on the cold walls.