R245fa與R152a及其混合冷媒之滴淋蒸發與池沸騰熱傳研究

A Heat Transfer Study of Falling Film Evaporation and Pool Boiling on Refrigerant R245fa, R152a and Their Mixtures

陳冠杰(Chen Guan-Jie)；簡良翰(Chien Liang-Han)；劉政勲(Liu Cheng-Hsun)

非共沸混合冷媒 ； 薄膜蒸發 ； 池沸騰 ； Non-azeotropic Refrigerants ； thin film evaporation ； pool boiling

冷凍空調&能源科技

117期（2019 / 09 / 10）

31 - 37

繁體中文;英文

環境保護並永續發展是必須被注重的議題，近年氣候變遷，災害不斷，也突顯了落實環保的重要性。本研究在飽和（沸騰）溫度25～70℃，並測試兩種純冷媒R245fa、R152a及兩種混合冷媒比例R245fa：R152a（3：1）、R245fa：R152a（3：1）應用在光滑管之滴淋蒸發與池沸騰熱傳性能，此四種冷媒實驗測試中，以純R152a的熱傳性能最佳。在未發生乾枯現象時熱傳係數受熱通量增加而上升。隨著飽和溫度升高，純R245fa、純R152a冷媒及其兩種混合比率流體之沸騰熱傳係數隨之提升。

Environmental protection and sustainable development are issues that drew a lot of attention. In recent years, climate change and series of disasters highlight the importance of environmental protection. In this study, two pure refrigerants R245fa、R152a and two mixed refrigerant ratios R245fa:R152a (3:1)、R245fa:R152a (3:1) were tested at saturation (boiling) temperature of 25~70 °C on smooth tubes. Both falling film evaporation and pool boiling heat transfer performance were tested. We found that the pure R152a yields the best performance. The the heat transfer coefficient increased by heat flux and temperature increased when dry up did not occur. For all fluids in the tests, the falling film evaporation and boiling heat transfer coefficients increase with increasing evaporation temperature.

1. Dang, Chao,Jia, Li,Peng, Qi,Huang, Qian,Zhang, Xuan(2017).Experimental and analytical study on nucleate pool boiling heat transfer of R134a/R245fa zeotropic mixtures.International Journal of Heat and Mass Transfer,119,508-522.
2. Holman, J. P.(1994).Experimental methods for engineers.McGraw-Hill, Inc..
3. Nagata, Ryuichi,Kondou, Chieko,Koyama, Shigeru(2016).Comparative assessment of condensation and pool boiling heat transfer on horizontal plain single tubes for R1234ze(E), R1234ze(Z), and R1233zd(E).International Journal of Refrigeration,63,157-170.
4. 蔡岳霖(2003)。國立臺北科技大學。