文献类型：期刊文献

中文题名：多组分降膜蒸发传热计算方法研究

英文题名：Calculation method of heat transfer in multi-component falling film evaporation

作者：孟祥宇[1];王学生[1];张庆[1];陈琴珠[1]

机构：[1]华东理工大学承压系统与安全教育部重点实验室,上海200237

年份：2020

卷号：48

期号：4

起止页码：22

中文期刊名：化学工程

外文期刊名：Chemical Engineering(China)

收录：CSTPCD;;Scopus;北大核心:【北大核心2017】；CSCD:【CSCD_E2019_2020】；

语种：中文

中文关键词：降膜蒸发器;传热机制;多组分;分段计算

外文关键词：Falling film evaporator;heat-transfer mechanism;multi-component;segmented calculation

摘要：在降膜蒸发器设计过程中,现有的多组分降膜蒸发传热计算方法未考虑传质的作用,其计算结果与实际工程设计相比存在较大的偏差。文中探讨了多组分降膜蒸发传热机制,充分考虑降膜蒸发的传热传质耦合作用,提出了适用于多组分降膜蒸发传热计算的关联式。针对多组分物料物性随蒸发浓缩发生变化的特点,建立了降膜蒸发器蒸发传热的分段设计方法。完成了丙二醇水溶液降膜蒸发不同单元数的分段传热计算,计算结果表明:分段计算与不分段计算的管内传热系数与总传热系数的偏差率分别为23%—30%及12%—16%。随着计算单元数的增加,降膜传热系数偏差率的变化会逐渐减小,设计计算过程中可以根据精度要求确定最佳计算单元数。此研究工作为降膜蒸发器的工艺设计提供了参考。
In the design process of falling film evaporator,the existing calculation methods of multi-component falling film evaporation heat transfer do not consider the role of mass transfer,and the calculation results are quite different from the actual engineering design.The heat transfer mechanism of multi-component falling film evaporation was discussed.Considering the coupling effect of heat and mass transfer of falling-film evaporation,a correlation formula suitable for heat transfer calculation of multi-component falling film evaporation was proposed.According to the characteristics that the physical properties of multi-component refrigerants change with evaporation concentration,a design method of heat transfer in falling film evaporator was established.The segmented heat transfer calculation for falling film evaporation of propylene glycol aqueous solution was completed.The results show that the deviation rates of heat transfer coefficients and total heat transfer coefficients are 23%-30%and 12%-16%respectively.With the increase of the number of calculation units,the variation of the deviation rate of falling film heat transfer coefficient will gradually decrease.The optimum number of calculation units can be determined according to the accuracy requirement in the design and calculation process.This study provides a reference for the process design of falling film evaporator.