气泡间距对受污染球形气泡界面性质和尾流的影响  

Effects of Bubble Spacings on Interface Properties and Wake Flow for 2 Contaminated Spherical Bubbles

作　　者：孙涛[1] 庞明军[1] 费洋[1] SUN Tao;PANG Mingjun;FEI Yang(School of Mechanical Engineering and Rail Transit,Jiangsu Key Laboratory of Green Process Equipment,Changzhou University,Changzhou,Jiangsu 213164,P.R.China)

机构地区：[1]常州大学机械与轨道交通学院,江苏省绿色过程装备重点实验室,江苏常州213164

出　　处：《应用数学和力学》2020年第10期1157-1170,共14页Applied Mathematics and Mechanics

基　　金：国家自然科学基金(51376026);江苏省高校“青蓝工程”项目资助。

摘　　要：为了理解气泡间相互作用对受污染气泡水动力学特性的影响,基于改进的停滞帽模型,以表面活性剂作为污染介质,详细研究了不同气泡间距下气泡的界面参数、周围流场和尾涡特性.通过求解气泡界面与流域间的吸附和解析方程,考虑局部流动以及Marangoni效应的影响,形成稳定的污染界面.借助Langmuir方程将界面切应力与界面表面活性剂浓度相关联,实现气泡界面切应力的求解.研究发现,改变两气泡的间距,不会显著影响气泡1的界面参数,而对气泡2的界面参数影响巨大.气泡1尾涡向气泡2上游界面的逼近是气泡2界面参数改变的主要原因,该尾涡对气泡2界面上表面活性剂分布的影响与对流作用相反,其可以把流向气泡2尾部的表面活性剂拖回气泡上游界面,从而影响气泡2的界面参数分布,并出现了低影响与高影响阶段.而且气泡1的尾涡长度和涡中心垂直位置的值受气泡2上游界面浓度和气泡间距的共同影响,气泡2各尾涡参数值随上游界面浓度的增加而减小直至为零.To understand the influence of the interaction between contaminated bubbles on the hydrodynamic characteristics,with a surfactant as the contamination medium,the interface pa⁃rameters,the flow field and the wake characteristics of bubbles with different spacings were in⁃vestigated with the improved stagnation cap model.A stably contaminated interface was formed through solution of the adsorption and desorption equations between the bubble interface and the fluid zone,and in view of the influence of the local flow and the Marangoni effect.The Langmuir equation was used to correlate the shear stress with the surfactant concentration of the interface to evaluate the bubble interface shear stress.The results indicate that,the change of the bubble spacing cannot significantly influence the interface parameters of bubble 1,but has great effects on those of bubble 2.The wake vortex of bubble 1 approaches the upstream in⁃terface of bubble 2,which changes the interface parameters of bubble 2.The influence of the wake vortex on the surfactant distribution on the interface of bubble 2 is different from that of the convection,which can drag the surfactant on the downstream interface of bubble 2 back to the upstream one,thus changing the distribution trend of the interface parameters of bubble 2,and there appear low⁃and high⁃influence stages.The vortex length and the vertical position of the vortex center of bubble 1 depend on the interface concentration on the upstream interface of bubble 2 and the bubble spacing.The vortex parameters of bubble 2 decrease with its interface concentration on the upstream interface till zero.

关 键 词：界面污染气泡 气泡间距 界面参数 局部流场 

分 类 号：O357.1[理学—流体力学] O359.1[理学—力学]