| Title |
Study on CO2 Evaporation Heat Transfer and PressureDrop in a Horizontal Smooth Tube |
| Authors |
이상재(sang-Jae Lee) ; 최준영(Jun-Young Choi) ; 이재헌(Jae-heon Lee) ; 권영철(Young-Chul Kwon) |
| Keywords |
증발 ; 열전달 ; 이산화탄소 ; 건도 ; 압력강하 Evaporation ; Heat transfer ; CO2 ; Quality ; Pressure drop |
| Abstract |
Experimental study on the heat transfer characteristics of CO2 in a horizontal smooth tube was carried out to investigate the heat transfer coefficient and pressure drop during evaporation of CO2. The experiment 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 (200～1200kg/m2s), heat fluxes (10～100kW/m2) and saturation temperatures (-5, 0, 5℃). With increasing the heat flux, the evaporation heat transfer coefficient increased. But the variation of the heat transfer coefficient on the increase of the mass flux was not large. And the significantly drops of the heat transfer coefficient was observed at any heat flux and mass flux because of the change of the flow pattern in the tube. With increasing the saturation temperature, the heat transfer coefficient increased due to the promotion of a nucleate boiling. The measured pressure drop during evaporation increased with increasing the mass flux and decreasing the saturation temperature. |