RB2-4 Shellside Condensation Finned Tube Bundle Pressure Drop Data

K. Ishihara and J. W. Palen

This research brief summarizes the results of the pressure drop part of the finned tube bundle condensation research project undertaken at HTRI since 1979. The pressure drop data accumulated from the HTRI boiling-condensing research plant cover a wide range of flow regimes from vacuum to high pressure on two types of finned tubes. The new data indicated that pressure drop predictions by the previous method were too low. The previous method used correlations for plain tube bundles described in HTRI Reports TPF-2 and TPF-3 as a tentative approach for finned tube bundles. At that time no data were available for confirmation.

New data have permitted the development of an effective diameter for finned tube pressure drop that permits use of the same correlations and methods for plain tubes, but accounts for the special crossflow characteristics of finned tubes. The effective diameter of the finned tubes is a function of fin geometries, fluid properties, and flow regimes.

A new research report (HTRI Report TPF-4) will be issued later to discuss this development.