3D unsteady numerical analysis on heat transfer performance of a fin-and-tube element in heat exchanger

摘要

A three dimensional unsteady numerical analysis has been made for a unit of single row plate-finned tube heat exchanger located in a uniform flow. The effects of Reynolds number and fin pitch on the local and mean Nusselt number and the pressure coefficient were examined parametrically. It is found that the flow unsteadiness affects the heat transfer from the fin-and-tube surface. As Reynolds number or fin pitch increases, flow unsteadiness is strengthened so that the size of the low heat transfer area of the fin behind the tube decreases and the pressure coefficient in the wake shows a peak based on local increasing of the momentum.