標題: R-22與二元近共沸混合冷媒R-410A於水平圓管內的蒸發熱流分析
An Investigation of Convective Evaporation of R-22 and Binary Near-Azeotropic Refrigerant Mixture R-410A in Horizontal Circular Tubes
作者: 余致廣
Yu, Jyh-Goang
盧定昶
Lu, Ding-Chong
機械工程學系
關鍵字: R-22;R-410A
公開日期: 1996
摘要: 賑膍s以實驗方法分別探討R-22及二元近共沸混合冷媒R-401A(R-32/R-125,
50%/150%,重量比)於內徑6.54mm的水平平滑管及6.48mm水平
微鰭管中的對流蒸發熱傳性能及兩相流動壓降。質量速度範圍為100∼
400kg/m2sec,飽和汽泡點溫度為2℃與10℃。實驗結果顯示R-410A在
平滑管及微鰭管內之熱傳係數均高於R-22,但在高質量速度及高乾度
區時,熱傳係數會有低落的現象。與平滑管相較,R-22於微鰭管的熱
傳係數提昇1.5∼2.4倍, R-410A則提昇1.5∼2.1倍。
本研究之實驗數據與前人之熱傳經驗式及壓降經驗式比對的結果,
Wattelet之經驗式能預測R-22於平滑管內之熱傳係數在±30%之內;
Souza之經驗式則能預測壓降在±30%之內。
The characteristics of convection evaporation heat transfer coefficients and two-phase flow pressure drops were measured for R-22 and binary near-azeotropic refrigerant mixture R-410A (R32/R125, 50%/50%, by weight) flowing in smooth tube with inner diameter of 6l.54 mm and micro-fin tubes with inner diameter of 6.48mm. The range of mass flux is between 100 to 400 kg/m2 sec, and data were taken at two evaporation temperature (2℃ and 10℃ respectively). The experimental results show that the heat transfer coefficient of R-410A is higher than R-22 in both smooth and micro-fin tubes, but it will be dacaied at high amss flux and high vapor quality region. Compare with smooth tubes, the heat transfer coefficients of R-22 in the micro-fin tubes increase by 150% 240% and the heat transfer coefficient of R-410A in the micro-fin tubes increase by 150% to 210%.
Between experimental data and correlations proposed for the heat transfer coefficients, Wattlet's correlation can predict R-22 datain smooth tube within ±30%. For the pressure drops, Souza's correlaiton can predict the data within ±30%.
URI: http://140.113.39.130/cdrfb3/record/nctu/#NT853489014
http://hdl.handle.net/11536/62361
顯示於類別:畢業論文