化工学报Issue(3)：924-931,8.DOI:10.11949/j.issn.0438-1157.20141404
超临界CO2/R41小通道内的换热特性
Heat transfer characteristics of supercritical CO2/R41 flowing in mini-channel
摘要
Abstract
An experiment was conducted to study the heat transfer characteristics of supercritical pure R41, mixtures of CO2/R41 (20.5/79.5), and CO2/R41 (51.4/48.6) cooled in a horizontal smooth mini-channel tube with inner-diameter of 2 mm. Mass flow rate was in the range of 400 to 800 kg·m−2·s−1, pressure changed from 6.0 to 8.0 MPa,heat flux ranged from 12 to 48 kW·m−2 and bulk temperature varied from 20℃ to 80℃. The maximum heat transfer coefficient (α) of the three fluids increased with the CO2 mass fraction. Additionally,αof pure R41 is smaller than that of the mixtures. However,αvariation tendency of the mixtures is the same as that of pure R41.αof the three working fluids are ranging from 2 kW·m−2·K−1 to 25 kW·m−2·K−1 under the present test condition. The influence of pressure is significant. The closer of the pressure approaches the critical pressure, the higher of the maximumαis. The heat flux has little influence onαwhen the bulk temperature is far away from the critical temperature. However for the bulk temperature near the critical temperature,αincreases with the decrease of heat flux. The experimental results are compared with prediction values calculated by twelve correlations. It is concluded that four correlations predicting with good precisions, and the errors are within ±30%. Nevertheless, the prediction errors increase with CO2 mass fraction.关键词
超临界CO2/R41/混合物/对流/换热/小通道Key words
supercritical CO2/R41/mixture/convection/heat transfer/mini-channel分类
能源科技引用本文复制引用
代宝民,李敏霞,吕佳桐,王派,马一太..超临界CO2/R41小通道内的换热特性[J].化工学报,2015,(3):924-931,8.基金项目
国家自然科学基金项目（50976075）；天津市科委基金项目（12JCYBJC13800）。@@@@supported by the National Natural Science Foundation of China (50976075) and the Tianjin Municipal Science and Technology Commission Foundation (12JCYBJC13800) （50976075）
