외경 5mm 수직 평활관 및 마이크로핀관 내의 이산화탄소/프로판 혼합냉매의 증발열전달 특성에 관한 실험적 연구 = An Experimental Study on the Evaporative Heat Transfer Characteristics of CO2/Propane Mixtures Flowing Upward in Vertical Smooth and Micro-fin Tubes with an Outer Diameter of 5mm

다국어 초록 (Multilingual Abstract)

Refrigerant mixtures provide an opportunity to adjust their properties to fit design criteria and a possibility to create new blends that can improve heat transfer characteristics. Therefore, mixture of CO2 and propane is chosen which may be a promising refrigerant and has good environmental compatibility. This paper presents measured heat transfer coefficient data during evaporation process of CO2/propane mixtures flowing upward in vertical smooth and micro-fin tubes. Smooth and micro-fin tubes with outer diameters of 5mm and length of 1.44m were selected as test tubes. The tests were conducted at mass fluxes of 212 to 656kg/㎡s, inlet temperatures of -10 to 30℃, heat fluxes of 15 to 60kW/㎡ and for several compositions (75/25, 50/50, 25/75wt%). Among CO2/propane refrigerant mixtures, the heat transfer characteristics are much better than that of any compositions when the composition is 75/25 (wt%).

참고문헌 (Reference)

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