S-SS-3-5 Tube-Baffle Leakage Flow Analysis for Integral Finned Tube Bundles

J. W. Palen and J. Taborek

A new correlation for the tube-baffle leakage ("A" stream) flow resistance coefficients was developed to predict the tube-to-baffle hole leakage flow rate for finned tube bundles which contain no lands (plain surface in the baffle holes). The new correlation is applicable to both gas and liquid streams when used in the HTRI Stream Analysis Method and reduces at the limit to the correlation for the plain tube bundles as derived in HTRI Report S-SS-3-1.

An analysis is also made in this report for the relative importance of the spiral channel flow of the fluid along the fin grooves around the tube hole area. The amount of spiral flow compared to the labyrinth flow is found to be significant only for 11 fins/in. or less fin density.

The predicted pressure drop of the single-phase finned tube data by the new correlation tested with the ST-4 Computer Program shows significant improvement in the higher Reynolds number range.