Numerical simulation of the flow and heat-transfer characteristics of an aligned external three-dimensional rectangular-finned tube bank

The results indicated that the heat transferability and friction loss of the aligned external three-dimensional rectangular-finned tube bank were higher than those of the smooth tube bank, while the comprehensive performance of external rectangular finned tube bank was not always superior. In addition, increasing the longitudinal tube pitch, fin height and fin width or decreasing the transverse tube pitch and fin pitch in the axial direction caused the heat-transfer capability and flow loss of the external rectangular-finned tube bank to increase, which can provide theoretical guidance for the design of a 3D finned-tube heat exchanger. The correlations of the Nusselt number (Nu) and the friction factor (f) for the six-row tube bank were presented, which can be helpful to engineering applications of heat exchanger for clean gas situations.