竖直管降膜蒸发器溢流孔式布膜器CFD模拟研究  

A study of film-forming effects in an overflow hole type liquid distributor of a vertical tube falling film evaporator

作　　者：李凯[1] 王庆锋[1] 郝帅[1] 李中[1] LI Kai WANG QingFeng HAO Shuai LI Zhong(College of Mechanical and Electrical Engineering, Beijing University of Chemical Technology, Beijing 100029, China)

机构地区：[1]北京化工大学机电工程学院,北京100029

出　　处：《北京化工大学学报（自然科学版）》2017年第1期57-62,共6页Journal of Beijing University of Chemical Technology(Natural Science Edition)

基　　金：国家"863"计划(2014AA041806);中国石油科技创新基金(2015D-5006-0606)

摘　　要：针对某公司在役竖直管降膜蒸发器换热效果不佳的问题,利用计算流体动力学(CFD)方法模拟研究了径向进液、切向进液以及溢流孔上方液位高度对成膜效果的影响,并进行了实验验证。模拟、实验研究发现:流体径向进入布膜器,仅部分流体沿壁面成膜,造成换热面积的有效利用率不足,进而导致蒸发器换热面积有效利用率低;采用切向孔进入布膜器,流体可在换热管壁面均匀成膜;溢流孔上方液位高度300 mm时可保证布膜均匀。In order to solve the problem of poor heat exchange efficiency in a commercial vertical tube falling film evaporator,we carried out simulations by computer fluid dynamics（CFD） of the effects on film formations of radial inlets,tangential inlets and varying liquid levels above the overflow hole and made a comparison with experiment.It was found that part of the fluid flows along the wall when radial inlets were adopted,which results in a loss of effective heat exchange area and reduces the heat exchange effect of the evaporator. When tangential inlets were adopted,a uniform film could be formed by the fluid along the heat exchange tube wall. In addition,to guarantee uniform film formation at the heat exchange tube inlet section of the evaporator,the liquid level height should not be less than 300 mm.

关 键 词：竖直管 溢流孔式 布膜器 计算流体动力学(CFD) 

分 类 号：TQ051.6[化学工程]