Heat transfer and friction characteristics of typical wavy fin-and-tube heat exchangers

Extensive experiments on the heat transfer and pressure drop characteristics of typical wavy fin-and-tube heat exchangers were carried out. In the present study, 18 samples of wavy fin-and-tube heat exchangers with different geometrical parameters, including the number of tube rows, lin pitch, and flow arrangements, were tested in a wind tunnel. Results are presented as plots of the Fanning friction factor f and the Colburn j factor against Reynolds number based on tube collar diameter in the range of 400 to 8000. Comparisons with the existing wavy fin correlations also are reported. It is found that fin pitch has negligible effect an the Colburn j factor, and the effect of tube row on friction factors is negligible. (C) Elsevier Science, Inc., 1997.