水平新型微肋管内流动冷凝换热及流阻特性

为研究微肋管结构尺寸及工况等对管内流动冷凝性能的影响，采用R22为工质对4种结构的微肋管和1根Ф9．52mm光管进行了实验．根据实验结果分析了质量流速、微肋结构尺寸和管径等对冷凝换热性能的影响．实验结果表明，两根Ф9．52mm微肋管的换热系数分别比光管提高了90％和120％，而其内表面积只比光管增加了40％和70％．

Flow condensation heat transfer and pressure drop in horizontal micro-fin tubes

The language of English journalistic headlines has a style of its own, which is characterized by succinctness in words, uniqueness in grammar, richness in rhetoric, and cleverness in punctuation. These features constitute a challenge to non-native English learners even though they have learned English for many years. This paper investigates these features from lexical, grammatical, rhetorical and punctual aspects.