制冷用水平管降膜蒸发器管束换热优化研究  

Optimization of Heat Transfer of Tube Bundle for Horizontal Falling Film Evaporator in the Large Refrigeration Systems

作　　者：李红民[1] Li Hongmin(School of Energy Science and Engineering,Central South University,Changsha 410083,China)

机构地区：[1]中南大学能源科学与工程学院

出　　处：《流体机械》2019年第5期74-78,共5页Fluid Machinery

摘　　要：采用降膜蒸发技术的制冷用降膜蒸发器是各空调企业争相研究的新型制冷设备。本文采用分布参数法建立水平管降膜蒸发器管束换热模型,针对管束进行优化研究,研究表明:管程采用水平布置,在保证总布液量不变的前提下,加大第一管程区域的布液量同时减小相应值的第二管程布液量,合理调整布液量可改善整体换热状况;管程采用上下布置,在干涸现象严重区域进行补液,可有效改善干涸现象,并且补液量并非越大越好,在补液量增加到一定量时,整体换热效果达到最佳。本文的研究为水平管降膜蒸发器的设计提供理论指导,促进其在制冷空调领域的推广应用。The falling film evaporator using the falling film evaporation technology is a new type of refrigeration equipment that many air conditioner manufacturing companies fall over each other in eagerness to research. In this paper,a theoretical thermodynamic model with distributed parameters was developed for simulating the falling film heat transfer performance. The research shows that when the tube course is horizontally arranged,under the premise that the total refrigerant distribution rate is guaranteed to be constant,the overall heat transfer can be improved by reducing the refrigerant distribution rate of second tube course of corresponding value while increasing the refrigerant distribution rate of the first tube course area and by appropriately adjusting the refrigerant distribution rate. When the vertical layout is adopted for the tube course,by refrigerant replenishment in the seriously dry region,the dryness phenomenon can be effectively improved,and the bigger the refrigerant replenishment volume, the better. When the refrigerant replenishment volume is increased to a certain amount,the best overall heat transfer performance is achieved. The present research provides theoretical guidance for the design of horizontal falling film evaporators and promotes their application in the field of refrigeration and air conditioning.

关 键 词：降膜蒸发 数值模拟 分布参数法 管束换热 

分 类 号：TH137.8[机械工程—机械制造及自动化]