本文主要以實驗方法分析冷媒R-134a與不同濃度潤滑油混合後，在管徑1.1mm及0.8mm混合物流經蒸發器之含油量變化，分析其冷媒流量與含油濃度之關係，實驗量測含油濃度由1 ~ 5%，質量速度為200 ~ 600 kg/m2s，熱通量為10 kw/m2。 本實驗入出口的含油濃度幾乎都會高於計算的局部油含量表示式，其改變的大小主要受到乾度和質量速度的影響，而質量速度愈小增加的量就愈大。本實驗在出口處的局部含油濃度並無預期中的減少，反而有增加的趨勢。造成這樣的結果，可能是本實驗系統的取樣裝置設計不良，由於本實驗所有的潤滑油皆會溶解於液態冷媒中，而取樣時只取到液態的混合物，並沒有取樣到上方的氣態冷媒，才會造成潤滑油濃度增加。 This paper used experimental analysis to R-134a mixture with different concentration of lubricant pass by evaporator in diameter 1.1mm and 0.8mm micro tubes. We analyzed the relation between flow rate of refrigerant and lubricant concentration. We measured lubricant concentration from 1 ~ 5%, mass velocity from 200 ~ 600 kg/m2s and fixed heat flux in 10 kW/m2 . The lubricant concentration of inlet and exit of test section were almost higher than calculated local lubricant concentration correlation. Local lubricant concentration influenced of vapor quality and mass velocity. When we decreased mass velocity, the local lubricant concentration increased. The local lubricant concentration of exit did not satisfy with our expect and trend to increase. To cause this experimental result, it maybe not design optimum of sample device. Due to all of lubricant dissolved in liquid refrigerant and we got the sample of lubricant only included the liquid mixture of refrigerant not included the gas mixture of refrigerant, therefore the lubricant concentration increase.
