| Title |
Experimental Study on Evaporation Heat Transfer and Oil Effect in Micro-fin Tube Using CO2 |
| Authors |
이상재(Sang-Jae Lee) ; 최준영(Jun-Young Choi) ; 이재헌(Jae-Heon Lee) ; 권영철(Young-Chul Kwon) |
| Keywords |
이산화탄소 ; 증발열전달 ; 오일영향 ; 마이크로핀관 ; 드라이아웃 Carbon dioxide ; Evaporation heat transfer ; Oil effect ; Micro-fin tube ; Dryout |
| Abstract |
In this paper, the experimental results on evaporation heat transfer characteris-tics were reported for a micro-fin tube using CO2. An experimental refrigerant loop had been established to measure the evaporation heat transfer coefficient and pressure drop of CO2. Experiments were conducted for mass fluxes, heat fluxes, saturation temperatures and PAG oil concentrations. With increasing the heat flux and the saturation temperature, the evapor-ation heat transfer coefficient increased. At the higher mass flux, however, the exit vapor quality of the micro-fin tube was to be lower. The peak of the heat transfer coefficient was shifted toward low quality region. The evaporation pressure drop increased as the mass flux increased and the saturation temperature decreased. As PAG oil concentration increased, the evaporation heat transfer coefficient decreased and the dryout was delayed by oil addition. |