احمد آذری

The performance of bilateral inclined solid and porous fins in natural convection within an H-shaped cavity with a hot bottom wall, cold vertical walls, and insulated horizontal walls are numerically investigated in this work. The key factors, namely Rayleigh number (Ra = 103
105), the porosity of fins (e = 0
1), Darcy number (Da = 10
10
10
2), inclination angle of fins (a = 68o,90o,112o), and the aspect ratio of the cavity (AR = 0.1, 0.2) are analyzed comprehensively in 180 cases. Porous zone governing equation and buoyancy force within the cavity are implemented by volume-average theory and Boussinesq approximation, respectively. A 60% enhancement in mean Nusselt number is observed in the presence of porous fins compared to the solid fins. The maximum Nusselt number is obtained by the perpendicular fins (a = 90o) and the aspect ratio of (AR = 0.2). In addition, the fins with the Darcy numbers (Da < 10
6) behave like solid fins. Finally, two correlations between the significant parameters and average Nusselt number are presented.