海水淡化系统水平管降膜蒸发器传热系数研究

针对海水淡化系统水平管降膜蒸发器,总结和分析管内冷凝侧与管外蒸发侧的换热系数关联式,比较管内径、入口蒸汽流速、蒸汽冷凝温度、出口蒸汽干度对管内蒸汽冷凝侧换热系数的影响;研究传热温差以及喷淋密度对管外蒸发侧换热系数的影响。结合不同的污垢系数,进行了总传热系数的影响因素分析,为海水淡化系统的工程设计提供依据。

Study on heat transfer coefficients of falling film evaporator with horizontal tube

For the falling film evaporator with horizontal tube in seawater desalination system,the heat transfer coefficients inside and outside the horizontal tube were summarized and analyzed.Not only the effects of tube diameter,inlet vapor velocity,steam condensing temperature and outlet vapor quality on the inside heat transfer coefficient,but also the effect of overall heat transfer temperature difference and flow density on the outside heat transfer coefficient were studied and compared.On these basis,the overall heat transfer coefficient was calculated in terms of different fouling resistance.The above study results provide a important basis for the project of thermal desalination plants.