Heat Transfer Performance of Internally Finned Tubes in Turbulent Flow

The heat transfer performance for heating water in turbulent flow was experimentally determined for II tubes having integral internal spiral and longitudinal fins. Eight of these tubes were previously tested with air and results have previously been reported. Individual tube performance is presented and compared with a smooth tube datum at constant pumping power. A longitudinal and spiral fin tube from within the II tubes and a smooth tube were also tested heating a 50% w/w ethylene glycol-water solution, and these data are included. These data are compared with relevant data available in the literature. Correlating equations are presented for heat transfer and Fanning friction factor that describe the air, water, and ethylene glycol-water data within ± 10%