ESG-4 Survey and Evaluation of Heat Transfer and Pressure Drop Correlations for Ideal Finned Tube Banks with Staggered Tube Layouts

T. Aoki and J. Taborek

A summary and evaluation of published correlation methods for predicting the performance of finned tube banks arranged in staggered layouts is presented in this report. A carefully selected set of data representing typical air cooler tubes is used to evaluate the correlation methods.

The first part of the report considers heat transfer correlations in which a Colburn j-factor is used as the basis of comparison. The results of the evaluations are presented in a series of error plots showing the ratio of predicted to experimentally obtained j-factors. A new HTRI correlation method is presented which is shown to be superior to previous methods.

Pressure drop correlations are presented in the second part of this report in which a Fanning friction factor is used as the basis of comparison. The evaluation of pressure drop correlations are presented in a manner similar to that for heat transfer correlations. A recommendation as to the best method is made.

For the first time a nonisothermal correction factor is introduced into the correlations for finned tube bank performance predictions. The correction has the same form but a different value for heat transfer and pressure drop.