Nucleate boiling heat transfer coefficients of HFO1234yf on various enhanced surfaces

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• 作者：Yohan Lee ; Dong-Gyu Kang ; Joo-Hyung Kim ; Dongsoo Jung
• 关键词：Nucleate boiling ; Heat transfer coefficient ; Alternative refrigerant ; Enhanced surfaces ; Evaporators ; HFO1234yf
• 刊名：International Journal of Refrigeration
• 出版年：February, 2014
• 年：2014
• 卷：38
• 期：Complete
• 页码：198-205
• 全文大小：1311 K

文摘

In this study, nucleate boiling heat transfer coefficients (HTCs) of HFO1234yf HFC134a are measured on a flat plain, Turbo-B, Turbo-C, and Thermoexcel-E surfaces. All data are taken at the liquid pool temperature of 7聽掳C on small flat horizontal square copper plates (9.53聽mm聽脳聽9.53聽mm) at heat fluxes from 10聽kW聽m^鈭? to 200聽kW聽m^鈭? with an interval of 10聽kW聽m^鈭?. Test results show that nucleate boiling HTCs of HFO1234yf on all four surfaces are similar to those of HFC134a at all heat fluxes tested in this study. At heat fluxes below 150聽kW聽m^鈭?, Thermoexcel-E surface shows the highest heat transfer performance and hence is the best surface for the manufacture of the evaporators in refrigeration and air-conditioning equipment. On the other hand, at high heat fluxes above 150聽kW聽m^鈭?, Turbo-B and Turbo-C show better heat transfer performance than Thermoexcel-E and hence are good for electronic cooling applications. Overall, HFO1234yf is a good long term candidate with excellent environmental properties to replace successfully HFC134a from the view point of pool boiling heat transfer. Hence HFO1234yf can be readily applied to the conventional evaporators designed for HFC134a.