浮力驱动气泡界面污染物浓度分布的理论分析  

Theoretical analysis on the concentration distribution of pollutant on the surface of a buoyancy-driven bubble

作　　者：费洋[1,2] 庞明军[1,2] 巢建伟[1,2] 陆敏杰 张展[1,2] FEI Yang;PANG Ming-jun;CHAO Jian-wei;LU Min-jie;ZHANG Zhan(School of Mechanical Engineering, Changzhou University,Changzhou 213164,Jiangsu Province,China;Jiangsu Key Laboratory of Green Process Equipment, Changzhou University,Changzhou 213164,Jiangsu Province,China)

机构地区：[1]常州大学机械工程学院,江苏常州213164 [2]常州大学江苏省绿色过程装备重点实验室,江苏常州213164

出　　处：《化学工程》2018年第10期1-6,共6页Chemical Engineering(China)

基　　金：国家自然科学基金资助项目(51376026);江苏省高校"青蓝工程"项目资助;江苏省大学生创新资助项目(20181029032Y)

摘　　要：目前有关气泡表面污染物浓度分布的理论研究大多基于蠕动流假设。为描述较大雷诺数(Reb> 1)下气泡表面污染物的浓度分布,基于吸附动力学理论和弱马兰戈尼效应假设,给出了动态平衡后停滞角和停滞帽中污染物浓度的表达式,以及动态平衡前停滞角随时间变化的表达式;基于气泡的瞬时上浮速度,对动态平衡前停滞帽中污染物浓度随时间的变化进行了讨论。结果表明:帽角的减小趋势随雷诺数的减小先减弱后增强;随着溶液中污染物初始浓度的增加,停滞角和停滞帽中污染物浓度的增速呈递减趋势,且停滞角增大到恒定值时所需的时间也随之减少;不同时刻下,停滞帽中污染物的浓度可近似看作常数。The recent theoretical studies about the concentration distribution of pollutant on the bubble surface were almost based on the assumption of creeping flow.Thus,it′s important to further extend the existing theories,so as to describe the concentration distribution at finite Reynolds numbers(Re b>1).The expressions of the stagnant angle and the pollutant concentration on the rear stagnant cap after the dynamic balance were evaluated,on the basis of sorption kinetics and weak Marangoni effect assumption.Then,the expression on the growth of the stagnant cap before dynamic equilibrium was also evaluated,under the above same two conditions.Besides,according to the instantaneous bubble rising velocity,the variation of pollutant concentration on the rear stagnant cap against time was discussed before dynamic equilibrium.The present results show that the decrease tendency of the cap angle decreases first,and then enhances with the decrease of Reynolds number.The growth rates of the stagnant cap and the pollutant concentration on the stagnant cap decrease with the increase of initial pollutant concentration in bulk,together with the decrease of time when the stagnant angle reaches a constant.The pollutant concentration on the rear stagnant cap changes very slightly against time,and it can be approximately equal to a constant.

关 键 词：受污染气泡 界面浓度分布 浮力驱动 理论分析 

分 类 号：O359.1[理学—流体力学] O647.1[理学—力学]