Experimental studies on condensation heat transfer of R404A outside horizontal low thermal conductivity tubes

The thermal conductivity of tube material has a significant effect on heat transfer coefficient of film condensation outside horizontal tube. Experimental studies of film condensation of R404A on single horizontal two-and three-dimensional finned tubes have been conducted. The results indicate that for the same tube material, the condensation heat transfer coefficient of R404A on three-dimensional finned tubes is larger than on two-dimensional finned tubes. And for the same surface structure, the lower thermal conductivity tubes obtain smaller condensation heat transfer coefficient.