Condensation heat transfer of HFC134a on horizontal low thermal conductivity tubes

Experimental studies of film condensation of HFC134a and CFC12 on single horizontal smooth tube and three enhanced tubes have been conducted. The objective is to obtain the basic data for film condensation of HFC134a on low thermal conductivity enhanced tubes. The results indicate that the predicted condensation heat transfer coefficients of HFC134a and CFC12 on smooth tube from Nusselt theory agree with the experimental data within ± 10%. The condensation heat transfer coefficients of HFC134a are about 32.6% larger than that of CFC12 for the cupronickel Thermoexcel-C tube. The cupreous integral-fin tubes provide more than twice condensation heat transfer coefficients than that of the cupronickel Thermoexcel-C tube. The heat transfer coefficients for each integral-finned tube are also compared with existing single-tube models.