CS-8 Condensation on 11-Fins-per-Inch Tube Bundles - Comparison with Previous Results

K. Ishihara

Heat transfer and pressure drop data were obtained on two types of 11 fins/in. tube bundles: the Wolverine S/T Trufin tube bundle and the Wieland GEWA-D finned tube bundle. Steam, p-xylene, n-pentane/p-xylene, N2/p-xylene, and N2/steam were used as test fluids.

The 11 fins/in. condenser bundles were found to give better heat transfer coefficients than 19 or 30 fins/in. tube bundles for p-xylene and steam, both of which have relatively high surface tension and viscosity. Good performance of the finned tubes is believed to be attained by low retention of condensate liquid on the fins due to their design.

The existing condensation heat transfer methods implemented in CST-2 Computer Program Mod. 0.2 were compared to the data of the 11 fins/in. tube bundles. These methods give good prediction for pure component data as well as hydrocarbon mixtures and mixtures with a noncondensable gas. The pressure-drop method developed in Research Brief 7-6 can predict tube bundle data within 3- percent of error range.