Share

Condensation heat transfer coefficients of the zeotropic refrigerant mixture R22/R142b in smooth horizontal tubes.

Author(s) : SMIT F. J., MEYER J. P.

Summary

Heat transfer coefficients during condensation of the zeotropic refrigerant mixture R22 with R142b are presented. Measurements were obtained at different mass fractions in a smooth horizontal tube. All measurements were conducted at a high condensing saturation pressure of 2.43 MPa, which corresponds to a condensation temperature of 60 °C for R22. The measurements were taken in 8.11 mm inner diameter smooth tubes with lengths of 1603 mm. The heat transfer coefficients were determined with the Log Mean Temperature Difference equations. It was found that at low mass fluxes, between 40 to 350 kg/m2.s, the refrigerant mass fraction influences the heat transfer coefficient by up to a factor of two. The heat transfer coefficients decrease as the fraction of R142b is increased. At high mass fluxes, of 350 kg/m2.s and more the heat transfer coefficients were not strongly influenced by the refrigerant mass fraction. The average heat transfer coefficient decreased by only 7% as the refrigerant mass fraction changed from 100% R22 to 50%/50% R22/R142b.

Details

  • Original title: Condensation heat transfer coefficients of the zeotropic refrigerant mixture R22/R142b in smooth horizontal tubes.
  • Record ID : 2004-2728
  • Languages: English
  • Publication date: 2002/07
  • Source: Source: Int. J. therm. Sci./Proc. ExHFT-5, Thessaloniki
    vol. 41; n. 7; 625-630; fig.; tabl.; 15 ref.

Indexing