Numerical Investigation of Natural Convection Heat Transfer on Aligned Arrangement Tube Banks

The aim of the present study is to numerical investigate the 2-D natural convection heat transfer on an aligned arrangement of tube banks. The fluid was considered to be Newtonian, laminar and steady state with Boussinesq approximation. Number of tube was varied from 6 to 8 and Rayleigh number changed from 106 to 108. The ratio of longitude distance to cylinder's diameter (dL /D) and the ratio of transverse distance to cylinder's diameter (dT /D) were varied in rang of 1.5, 2 and 3. Tubes diameter and the passing air temperature were assumed to be 30 cm and 300K respectively. The computational fluid dynamics was used to investigate the changes of the mean Nusselt number of the fluid passing through aligned arrangement of tube banks. The results showed that the maximum heat transfer rate was for the case with dT /D=2, dL /D=2 and Ra=108 characteristics.