ESG-12 Pitch and Layout Effects on Heat Transfer and Pressure Drop of High-Finned Tube Banks

A. Ganguli

Test data are reported on the heat transfer and pressure loss of several ideal high-finned tube banks tested in the HTRI Wind Tunnel. Data were obtained on the thermal hydraulics of typical 1-in. (25.4-mm) and 1.5-in. (38.1-mm) OD finned tubes arranged in equilateral and nonequilateral staggered layouts and with wide pitches. The presently recommended HTRI correlations were tested against the data.

The pressure drop data for nonequilateral staggered layouts were found to be underpredicted by about 20 percent, while the remaining heat transfer and pressure drop data were predicted to within ± 15 percent. A new correlation has been developed for the longitudinal pitch correction factor, lambda sub l, and applied to the estimation of f-factors for nonequilateral layouts. The new correlation predicts all the available data within a ± 10 percent error range.