CFD Analysis of Convective Heat Transfer for Nanoparticles and Porous Medium

Water flowing in circular pipe heated horizontally with constant heat flux has been used to evaluate numerically force convection heat transfer. In order to create porous media, stainless-steel balls of two sizes (1 mm and 3 mm) have been inserted into fully developed pipe to give distinct porosity values (0.3501 and 0.3558). Reynolds numbers have ranged from 5000 to 9000, with heat flux rates of 10,000, 12,000, and 14,000 W/m2 depending on tube diameter. The internal diameter has been 51.4mm, 5mm thickness, and 304mm heating distance. Nanoparticles improve thermophysical properties of porous media. Stainless steel pipe has been simulated by using CFD. Eddy creation has increased the flow turbulently. The Reynolds number directly affects pressure drop and the Nusselt number. Reynolds number has increased as the outlet temperature has lowered, reducing heat flux. Nusselt number has risen with a ball diameter of 1 mm to 3 mm. The pipe pressure drop has dropped 74.84% to 1.6% porosity. Nusselt number has increased by 6.8% when Reynolds number has increased by 33% and 21.9% when heat flux has increased by 28.57%. Additionally, nanofluid2 has 32.27% higher Nusselt than the porous medium. Although nanofluid 2 transfers heat more effectively than nanofluid1, nanofluid2 has a higher pressure drop than nanofluid1, because CuO nanoparticles (Nanofluid2) may be denser and more viscous than SiO2 nanoparticles.