R410A-油在7mm C形光管流动沸腾的压降特性

Frictional Pressure Drop Characteristics of R410A-Oil Flow Boiling in 7mm C-Shape Horizontal Smooth Tube

对R410A-油在7 mm C形水平光管内流动沸腾的压降特性进行了研究,并基于混合物性开发出7 mm C形水平光管内流动沸腾的压降预测关联式.测试段长度2 m,实验工况：质量流率为200,300,400 kg/（m^2·s）;蒸发温度5℃;入口干度0.2～0.7;测试段干度变化0.2;润滑油质量分数1%～5%.润滑油的存在引起压降增大,不同干度下,压降都随油浓度的增加而增大,压降最大增加33.5%.基于混合物性开发的关联式预测值与80%以上的实验数据偏差在±15%以内,平均偏差9.13%,最大偏差28.97%.

Evaporation pressure drop characteristics of R410A-oil mixture in 7 mm C-shape smooth tube were investigated. The experiment was carried out at evaporation temperature 5 ℃, and inlet quality ranges from 0.2 to 0.7, quality change of test is section 0.2, oil concentration ranges from 1% to 5 %, mass flux range from 200 to 400 kg/（m^2 · s）. Oil increases the pressure drop, and the pressure drop becomes much larger with the increase of oil concentration, and the largest increase of pressure drop caused by oil is about 33.5% as compared to that of pure refrigerant. A new pressure drop correlation for R410A-oil mixture in 7 mm C-shape smooth tube is developed based on refrigerant-oil mixture properties. It can agree with 80% experimental data within deviation of ± 15% and the average deviation and maximum deviation are 9.13% and 28.97% respectively.