高黏流体在折流板上的降膜流动  

Falling film flow of high viscosity fluid on baffle plates

作　　者：赵俏[1,2] 齐文哲 刘晨[1,2] 张小波[1,2] 刘春江[1,2] 

机构地区：[1]天津大学化工学院化学工程联合国家重点实验室,天津300072 [2]天津化学化工协同创新中心(天津大学),天津300072

出　　处：《化学工程》2016年第5期48-52,共5页Chemical Engineering(China)

基　　金：国家重点基础研究发展计划项目(973计划)(2013CB720500)

摘　　要：为探究高黏流体在开窗导流填料片上的流动性能,文章采用多折流板结构代替开窗导流填料片结构,利用激光多普勒测速仪(LDA)测量了水溶性硅油在多折流板上的流动情况。通过移动测速仪的坐标架,可测得降液膜沿横向、纵向和膜厚方向的速度分布;通过观察仪器显示屏上的速度信号,可计算出液膜的厚度。比较不同折流板上的速度及膜厚差别,实验发现在低流速下(Re<10),折流板通过改变流体流动方向,使流体产生了明显的波动,从而加强了表面更新。实验还发现,在各个位置上速度沿膜厚方向的分布,均呈现出了类抛物线状,在气液接触面处速度有降低的趋势。同时,实验研究了液体流量、黏度对膜厚的影响,并回归出经验公式、经验值与实验值的误差在6%之内,可应用于硅油在折流板上流动。To investigate the flow performance of high viscous fluid flowing on structured packing sheet with multibaffled configuration,the flow characteristics of high viscous silicone oil on the baffled plates were measured by Laser Doppler Anemometer（ LDA）. By moving the anemometer＇s coordinate frame,the falling film velocity distribution can be measured. According to the signal displayed on the screen,film thickness can be acquired. By comparison of the velocity distribution and film thickness on different baffle plates,the result shows that the baffle plates can enhance surface update even at low velocity（ Re 10）,due to the altered direction and the obvious fluctuation on the fluid surface. It also shows that the velocity distribution along the thickness direction is like a parabolic curve,and the velocity has the decrease tendency at the interface of liquid and gas. The influence of flow rate and viscosity on the film thickness was researched. The empirical formula was obtained that can be applied to the situation of silicone oil flowing on baffle plates. The error between fitting value and experiment value is within 6%.

关 键 词：降膜流动 高黏流体 折流板 激光多普勒测速(LDA) 膜厚 

分 类 号：TQ021.1[化学工程]