Heat transfer investigation in a three dimensional annulus made of laminated composite Aluminum/hexadecane and filled with porous media

Heat transfer by natural convection of air flow has been studied numerically in a three dimensional inclined annulus. Two cases are taken for the annulus material which is made of laminated composite materials. Aluminum/Hexadecane phase change material (PCM) is taken in the first case and pure hexadecane material in the second case for the purpose of comparison. The annulus enclosure is filled with porous media between two inclined concentric cylinders under steady state condition and constant wall temperature boundary condition. The parameters affected on the system are modified Rayleigh number (10 ≤Ra*≤ 1000), radius ratio Rr (0.2, 0.3, 0.4 and 0.5) and the annulus inclination angle δ (0, 30, 45, 60 and 90). The results show a maximum heat transfer for horizontal Aluminum/Hexadecane annulus which increases with the increase of Ra* and Rr. The maximum variance in heat transfer for the two materials is 65.4% for horizontal annulus with Rr=0.2 and Ra*=1000. A correlation of Nu in terms of Ra*, Rr and the annulus inclination angle δ has been developed for the two cases.