Flow Boiling Heat Transfer of R-22 in a Flat Extruded Aluminum Multi-Port Tube

  • Kim Nae-Hyun (Department of Mechanical Engineering, University of Incheon) ;
  • Sim Yang-Sup (Graduate School, University of Incheon) ;
  • Min Chang-Keun (Graduate School, University of Incheon)
  • Published : 2004.09.01

Abstract

Convective boiling heat transfer coefficients of R-22 were obtained in a flat extruded aluminum tube with $D_h=1.41mm$. The test range covered mass flux from 200 to $600kg/m^{2}s$, heat flux from 5 to $15kW/m^2$ and saturation temperature from $5^{\circ}C\;to\;15^{\circ}C$. The heat transfer coefficient curve shows a decreasing trend after a certain quality (critical quality). The critical quality decreases as the heat flux increases, and as the mass flux decreases. The early dryout at a high heat flux results in a unique 'cross-over' of the heat transfer coefficient curves. The heat transfer coefficient increases as the mass flux increases. At a low quality region, however, the effect of mass flux is not prominent. The heat transfer coefficient increases as the saturation temperature increases. The effect of saturation temperature, however, diminishes as the heat flux decreases. Both the Shah and the Kandlikar correlations un-derpredict the low mass flux and overpredict the high mass flux data.

Keywords

References

  1. Katsuta, M., 1994, The effect of a cross-Sectional geometry on the condensation heat transfer inside multi-pass Tube, Proc. WTPF, POSTECH, Vol. 2, pp.245-252
  2. Yang, C. Y. and Webb, R. L., 1996, Condensation of R-12 in small hydraulic diameter extruded aluminum tubes with and wthout micro-fins, Int. J Heat Mass Trans., Vol.39, pp. 791-800
  3. Koyama, S., Kuwahara, K., Nakashita, K. and Yamamoto, K., 2002, An experimental study on condensation of R134a in a multiport extruded tube, Proceedings of 2002 International Refrigeration Conference at Purdue, R6-2
  4. Kim, N.-H., Cho, J-P., Kim, J.-O. and Youn, B., 2003, Condensation heat transfer of R-22 and R-410A in flat aluminum multi-channel tubes with or without microfins, Int. J. Refrigeration, Vol. 26, pp. 830-839
  5. Yan, Y.-Y. and Lin, T.-F., 1998, Evaporation heat transfer and pressure drop of refrigerant R-134a in a small pipe, Int. J. Heat Mass Transfer, Vol. 41, pp.4183-4194
  6. Yan, Y.-Y. and Lin, T.-F., 2003, Letter to the editors; Reply to Prof. R. L. Webb and J. W. Paek's Comments, Int. J. Heat Mass Transfer, Vol. 46, pp. 1111-1113
  7. Zhao, Y., Molki, M. and Ohadi, M. M., 2000, Heat transfer and pressure drop of $CO^2$ flow boiling in microchannels, Proceedings of the ASME Heat Transfer Division, HTD-Vol.366-2, Vol. 2, pp.243-249
  8. Zhao, Y., Molki, M. and Ohadi, M. M., 2001,Predicting flow boiling of $CO^2$ in microchannels, Proceedings of 2001 International Mechanical Engineering Congress and Exposition, HTD-Vol. 369-3, IMECE2001/HTD-24216, pp. 205-210
  9. Liu, Z. and Winterton, R. H. S., 1991, A general correlation for saturated and subcooled flow boiling in tubes and annuli based on a nucleate pool boiling equation, Int. J. Heat Mass Transfer, Vol. 34, pp.2759-2766
  10. Cornwell, K and Kew, P. A., 1993, Boiling in small parallel channels, in energy efficiency in process technology, ed., P. A. Pilvachi, New York, Elsevier, pp. 624-638
  11. Pettersen, J., 2003, Two-phase flow pattern, heat transfer and pressure drop in microchannel vaporization of $CO^2$, ASHRAE Transactions, Vol. 109, Pt.1, CH-03-8-1
  12. Shah, M. M. and Siddiqui, M. A., 2000, A general correlation for heat transfer during dispersed-flow film boiling in tubes, Heat Transfer Engineering, Vol. 21, No.4, pp.18-32
  13. Kon'kov, A.S., 1965, Experimental study on the conditions under which heat exchange deteriorates when a steam-water mixture flows in heated tubes, Teploenergetika, Vol.13, No.2, p.77
  14. Agostini, B., Bontemp, A., Watel, B. and Thonon, B., 2003, Boiling heat transfer in mini-channels: influence of the hydraulic diameter, International Congress of Refrigeration 2003, Washington D. C., ICR0070
  15. Kandlikar, S. G. and Steinke, M. E., 2003, Predicting heat transfer during flow Boiling in minichannels and microchannels, ASHRAE Transactions, Vol. 109, Pt.1, CH-03-13-1
  16. Kandlikar, S. G., 1990, A general correlation for saturated two-phase flow boiling heat transfer inside horizontal and vertical tubes, J. Heat Transfer, Vol.112, pp.219-228
  17. Webb, R. L. and Paek, J. W., 2003, Letter to the editors; Discussions on Y.-Y. Yan and T.-F. Lin's paper, Int. J. Heat Mass Transfer, Vol.46, pp.1111-1113
  18. Kline, S.J. and McClintock, F. A., 1953, The description of uncertainties in single sample experiments, mechanical engineering, Vol. 75, pp.3-9
  19. Hapke, I., Boye, H. and Schmidt, r, 2000, Flow boiling of water and n-heptane in micro-channels, in heat transfer and transport phenomena in microscales, G. P. Celata et al., eds., Begell House, Inc., pp. 222-228
  20. Coleman, J. W. and Garimella, S., 1999, Characterization of two-phase flow patterns in small diameter round and rectangular tubes, Int. J. Heat Mass Trans., Vol. 42, pp. 2869-2881
  21. Shah, M. M., 1976, A new correlation for heat transfer during boiling flow through pipes, ASHRAE Trans., Vol. 82, Pt. 2, pp.66-86
  22. Dittus, F. W. and Boelter, L. M. K., 1930, Heat transfer in automobile radiators of a tubular type, university of california publication on engineering, Vol. 2, p.433
  23. Petukhov, B. S., 1970, Heat transfer in turbulent pipe flow with variable physical properties, in advances in heat transfer, eds. T. F. Irvine and J. P. Hartnett, Academic Press, Vol. 6, pp.504-564
  24. Gnielinski, V., 1976, New equations for heat and mass transfer in turbulent pipe and channel flow, International Chemical Engineering, Vol. 16, pp.359-368