| Title |
Experimental Study on Characteristics of Evaporation Heat Transfer and Oil Effect of CO2 in Mini-channels |
| Authors |
이상재(Sang-Jae Lee) ; 김대훈(Dae-Hoon Kim) ; 최준영(Jun-Young Choi) ; 이재헌(Jae-heon Lee) ; 권영철(Young-Chul Kwon) |
| Keywords |
이산화탄소 ; 증발열전달 ; 오일영향 ; 압력강하 ; 미세채널 CO2 ; Evaporation heat transfer ; Oil effect ; Pressure drop ; Mini-channels |
| Abstract |
In order to investigate CO2 heat transfer coefficient and pressure drop by PAG oil concentration during CO2 evaporation, the experiment on evaporation heat transfer characteristics in a mini-channels were performed. The experimental apparatus consisted of a test section, a DC power supply, a heater, a chiller, a mass flow meter, a pump and a measurement system. Experiment was conducted for various mass fluxes(300～800kg/m2s), heat fluxes(10～40kW/m2), saturation temperatures(-5～5℃), and PAG oil concentration(0, 3, 5wt%). The variation of the heat transfer coefficient was different according to the oil concentration. With the increase of the oil concentration, the evaporation heat transfer coefficient decreased and the delay of dryout by oil addition was found. Pressure drop increased with the increase of the oil concentration and heat flux, and the decrease of saturation temperature. |