| Title |
R-22 and R-410A Condensation in Flat Aluminum Multi-Channel Tubes |
| Keywords |
Flat tube ; 평판관 ; Multi-channel tube ; 다채널 관) Condensation ; 응축 ; R-22, R-410A |
| Abstract |
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. Two internal geometries were tested; one with a 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(200～600kg/m2s) and heat flux(5～15kW/m2). 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 for 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 reverse is true. Possible reasoning is provided considering the physical properties of the refrigerants. For the smooth tube, a correlation of Akers et al. type predicts the data reasonably well. For the micro-fin tube, the Yang and Webb model was modified to correlate the present data. |