CS-3 Shellside Condensation of Pure Components on the Outside of Horizontal Finned Tube Bundles

K Ishihara, J. W. Palen, and A. E. Kassem

Extensive data have been accumulated at HTRI for the shellside condensation heat transfer on two types of integral low-finned tube bundles. The data covered a full range of flow regimes from gravity- to shear-controlled regimes for pure fluids over a wide range of fluid properties from low surface tension to very high surface tension.

A major modification of the previous method has been made in the heat transfer correlations for both gravity-controlled and shear-controlled flow regimes based on these new data which include the visual observation of the actual condensing process recorded on a film. However, no changes were made to the basic calculation structure of the shellside condensation method, in which the heat transfer process during condensation is modeled by either a shear-controlled flow mechanism or a gravity-controlled flow mechanism.

The major improvements in the new method as compared to the previous method are in the following areas:

  • Introduction of an effective finned tube diameter to account for the presence of condensate
  • Effect of condensate retention flooding a portion of the heat transfer surface
  • Effect of condensate loading on film thickness
  • Two-phase convection factor constants developed especially for finned tubes

The new method significantly improves the prediction of shellside pure component condensation heat transfer coefficients.