Heat Transfer around Tubes in Staggered Tube Banks

Abstract

An experimental study was conducted to investigate the heat transfer and flow around tubes in staggered tube banks in a cross flow of air. The cylinder spacings examined C_y/d x C_x/d are 1.6 x 1.6 and 1.2 x 1.2 where C_x and C_y denote the cylinder spacings along and normal to the upstream uniform flow direction, and d the cylinder diameter, respectively. Main results obtained are as follows. In case of 1.2 x 1.2, the mean Nusselt numbers for the second and subsequent cylinders are almost equal to each other and much higher than that for the first cylinder. In case of 1.6 x 1.6, the third cylinder exhibits the maximum heat transfer rate. This may be due to the high velocity of an oncoming flow to that along with its high turbulence intensity.