A comparison of the tube-side performance of enhanced heat transfer tubing for naval condensers

Abstract

The data of several investigators conducting research in the area of enhanced heat transfer in internally ribbed and spirally corrugated tubes is compiled and examined to determine the effects of the geometric characteristics of enhanced tubing on flow resistance and heat transfer. The data are compared to determine if there are any relations, either new or previously published, which can be of use to the designer to predict the friction factor and heat transfer coefficient for a specified enhanced tube. Empirical relations are recommended for friction factor and heat transfer coefficient for single-start and multiplestart spirally corrugated tubes based on the lav/ of the wall similarity analysis and a heat transfer similarity analysis. The empirical relations are compared to experimental data for single-start and multiple-start corrugated tubes with pitch-to-groove ratios greater than 10 and dimensionless groove depths less than 0.05. The recommended relations correlate with the experimental data for heat transfer coefficient within ±15% for 94% of the specified tubes.