Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Flow Condensation Heat Transfer Characteristic of R245fa in a Horizontal Plain Tube

수평 평활관내 R245fa의 흐름 응축 열전달 특성

  • Published : 2008.02.10
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Abstract

Flow condensation heat transfer coefficients(HTCs) of R123 and R245fa are measured in a horizontal plain tube. The main test section in the experimental flow loop is made of a plain copper tube of 9.52 mm outside diameter and 530 mm length. The refrigerant is cooled by passing cold water through an annulus surrounding the test section. Tests are performed at a fixed saturation temperature of $50\;{\pm}\;0.2\;^{\circ}C$ with mass fluxes of 50, 100, $150\;kg/m^2s$ and heat flux of $7.3{\sim}7.7\;kW/m^2$. Heat transfer data are obtained in the vapor quality range of $10{\sim}90%$. Test results show that the flow condensation HTCs of R245fa are overall 7.9% higher than those of R123 at all mass fluxes. The pressure drop of R245fa is smaller than that of R123 at the same heat flux. In conclusion, R245fa is a good candidate to replace ozone depleting R123 currently used in chillers from the view point heat transfer and environmental properties.

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References

  1. Molina, M. J. and Rowland, F. S., 1974, Stratospheric sink for chlorofluoromethanes : chlorine atom catalyzed destruction of ozones, Nature, Vol. 249, pp. 810-812 https://doi.org/10.1038/249810a0
  2. Montreal protocol on substances that deplete the ozone layer, 1989, Final Act, United Nations Environment Programme
  3. Global Environmental Change Report, 1997, A brief analysis of the Kyoto protocol, Vol. 4, No. 24, December
  4. Marto, P. J. and Nunn, R. H., 1981, Power condenser heat transfer technology, Hemisphere Washington, pp. 287-372
  5. Bergles, A. E., 1985, Techniques to augment heat transfer, Handbook of heat transfer application, McGraw-Hill, New York, Ch. 3
  6. Calm, J. M. and Hourahan, G. C., 2001, Refrigerant data summary, Engineered Systems, Vol. 18, No. 11, pp. 74-88
  7. Furuta, T., 2006, Development of centrifugal refrigeration machine with R245fa, The International Symposium on New Refrigerants and Environmental Technology 2006, Session 7
  8. Furuta, T., 2006, Development of centrifugal refrigeration machine with R245fa, The International Symposium on New Refrigerants and Environmental Technology 2006, Session 7
  9. Angelino, G. and Invernizzi, C. C., 2003, Experimental investigation on the thermal stability of some new zero ODP refrigerants, International Journal of Refrigeration, Vol. 26, pp. 51-58 https://doi.org/10.1016/S0140-7007(02)00023-3
  10. Kwon, O. B., Oh, H. K., Oh, J. T. and Kim, S. G., 1993, Condensation heat transfer characteristics of HCFC-123 inside horizontal smooth tube, Journal of the Korean Society of Marine Engineering, Vol. 17, No. 3, pp. 160-168
  11. Jung, D., Song, K. H., Cho, Y. M. and Kim, S. J., 2003, Flow condensation heat transfer coefficients of pure refrigerants, International Journal of Refrigeration, Vol. 26, No. 1, pp. 4-11 https://doi.org/10.1016/S0140-7007(02)00082-8
  12. Lim, T. W., 2005, Flow pattern and pressure drop of pure refrigerants and their mixture in horizontal tube, Journal of Mechanical Science and Technology, Vol. 19, No. 12, pp. 2289-2295 https://doi.org/10.1007/BF02916469
  13. Lemmon, E. W., McLinden, M. O. and Huber, M. L., 2003, NIST reference fluid thermodynamic and transport properties, REFPROP version 7.1
  14. Kline, S. J. and McClintock, F. A., 1953, Describing Uncertainties in Single Sample Experiments, Mechanical Engineering Vol. 75, pp. 3-8
  15. Kim, S. J., Song, K. H. and Jung, D., 2002, Flow condensation heat transfer coefficients of pure refrigerants, Korean Journal of Air- Conditioning and Refrigeration Engineering, Vol. 14, No. 2, pp. 175-183
  16. Dobson, M. K. and Chato, J. C., 1998, Condensation in smooth horizontal tubes, ASME J. Heat Transfer Vol. 120, pp. 193-213 https://doi.org/10.1115/1.2830043
  17. Jung, D. S., Mclinden, M., Radermacher, R. and Didion, D., 1989, A study of flow boiling heat transfer with refrigerant mixture, International Journal of Heat Mass Transfer, Vol. 32, No. 9, pp. 1751-1764 https://doi.org/10.1016/0017-9310(89)90057-4
  18. Akers, W. W., Deans, H. A. and Crosser, O. K., 1959, Condensation heat transfer within horizontal tubes, Chem. Eng. Prog. Symp. Ser. Vol. 55, No. 29, pp. 171-176
  19. Soliman, H. M., Schuster, J. R., and Berenson, P. J., 1968, A General heat transfer correlation for annular flow condensation, J. Heat Transfer, Vol. 90, pp. 167-176
  20. Traviss, D. P., Rohsenow, W. M. and Baron, A. B., 1973, Forced convection condensation in tubes : A heat transfer correlation for condenser design, ASHRAE Trans., Vol. 79, Part 1, pp. 157-165
  21. Cavallini, A. and Zecchin, R., 1974, A dimensionless correlation for heat transfer in forced convection condensation, Proceedings of the Fifth International Heat Transfer Conference, Vol. 3, pp. 309-313
  22. Shah, M. M., 1979, A General correlation for heat transfer during film condensation inside pipes, International Journal of Heat Mass Transfer, Vol. 22, pp. 547-556 https://doi.org/10.1016/0017-9310(79)90058-9