Browse > Article

R-22 and R-410A Condensation in Flat Aluminum Multi-Channel Tubes  

Kim, Nae-Hyun (Department of Mechanical Engineering, University of Incheon)
Min, Chang-Keun (Graduate School, University of Incheon)
Jung, Ho-Jong (Graduate School, University of Incheon)
Publication Information
International Journal of Air-Conditioning and Refrigeration / v.11, no.3, 2003 , pp. 114-124 More about this Journal
In this study, condensation heat transfer tests were conducted in flat aluminum multi-channel tubes using R-410A, and the results are compared with those of R-22. The flat tubes have two internal geometries; one with smooth inner surface and the other with micro-fins. Data are presented for the following range of variables; vapor Quality (0.1∼0.9), mass flux (200∼600 kg/$m^2$s) and heat flux (5∼15 kW/$m^2$). Results show that the effect of surface tension drainage on the fin surface is more pronounced for R-22 than R-410A. The smaller Weber number of R-22 may be responsible. For the smooth tube, the heat transfer coefficient of R-410A is slightly larger than that of R-22. For the micro-fin tube, however, the trend is reversed. Possible reason is provided considering physical properties of the refrigerants. For the smooth tube, Webb's correlation predicts the data reasonably well. For the micro-fin tube, the Yang and Webb model was modified to correlate the present data. The modified model adequately predicts the data.
Condensation; Multi-channel; Small diameter; R410A; R-22; Tube;
Citations & Related Records
연도 인용수 순위
  • Reference
1 Yang, C. Y. and Webb, R. L., 1996, Condensation of R-12 in small hydraulic diameter extruded aluminum tubes with and without micro-fins, Int. J. Heat Mass Trans., Vol. 39, No.4, pp. 791-800
2 Shah, M. M., 1979, A general correlation for heat transfer during film condensation in tubes, Int. J. Heat Mass Transfer, Vol. 22, No. 4, pp. 547-556
3 Carnavos, T. C., 1979, Cooling air in turbulent flow with internally finned tubes, Heat Transfer Engineering, Vol. 1, No. 2, pp. 41-46
4 Kwon, J. T., Park, S. K. and Kim, M. H., 2000, Enhanced effect of a horizontal microfin tube for condensation heat transfer with R22 and R410A, J. Enhanced Heat Transfer,Vol. 7, pp. 97-107
5 Tang, L., Ohadi, M. M. and Johnson, A. T., 2000, Flow condensation in smooth and micro-fin tubes with HCFC-22, HFC-134a and HFC-410A refrigerants, J. Enhanced Heat Transfer, Vol. 7, pp. 289-310
6 Wijaya, A. and Spatz, M. W., 1994, Two-phase flow condensation heat transfer and pressure drop characteristics, Proceedings of 1994 International Refrigeration Conference at Purdue, pp.305-310
7 Zivi, S. M., 1964, Estimation of steady state steam void fraction by means of principle of minimum entropy production, J. Heat Trans., Vol. 86, pp. 237-252
8 Kline, S. J. and McClintock, F. A., 1953, The description of uncertainties in single sample experiments, Mechanical Engineering, Vol. 75, p. 3-9
9 Moser, K., Webb, R. L. and Na, B., 1998, A new equivalent Reynolds number model for condensation in smooth tubes, J. Heat Trans., Vol. 120, pp. 410-417
10 Kim, N. H., Cho, J. P. and Kim, J. O., 2000, R-22 condensation in flat aluminum multichannel tubes, J. Enhanced Heat Transfer, Vol. 7, pp. 427-438
11 Akers, W. W., Deans, H. A. and Cosser, O. K., 1959 Condensation heat transfer within horizontal tubes, Chem. Eng. Progress Symp. Series, Vol. 55, No. 29, pp.171-176
12 Webb, R. L. and Yang, C. Y., 1995, A comparison of R-12 and R-134a condensation inside small extruded aluminum plain and micro-fin tubes, C4961053195, IMechE, pp.77-86
13 Yang, C. Y. and Webb, R. L., 1997, A predicted model for condensation in small hydraulic diameter tubes having axial microfins, J. Heat Trans., Vol. 119, pp.776-782
14 Friedel, L., 1979, Improved friction pressure drop correlations for horizontal and vertical two phase pipe flow, Paper E2, EuropianTwo Phase Flow Group Meeting, Ispra, Italy
15 Farrell, P., Wert, K. and Webb, R. L., 1991, Heat transfer and friction characteristics of turbulator radiator tubes, SAE Technical Paper Series 910197
16 Webb, R. L., 1998, Prediction of condensation and evaporation in micro-fin and microchannel tubes, In: Kakac, S., Bergles, A. E., Mayinger, F. and Yuncu, H., editors, Heat transfer enhancement of heat exchangers: Kluwer Academic Publishers, pp. 529-550