无重力下油颗粒在纤维表面的形貌特征分析  

Analysis on shape characteristic of oil droplet on fiber without gravity

作　　者：徐成威 于燕 谢文霞[3] 张军[3] 杨建刚[3] Xu Chengwei;Yu Yan;Xie Wenxia;Zhang Jun;Yang Jiangang(College of Electrical,Energy and Power Engineering,Yangzhou University,Yangzhou 225127,China;College of Engineering,Hebei Normal University,Shijiazhuang 050024,China;Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education,Southeast University,Nanjing 210096,China)

机构地区：[1]扬州大学电气与能源动力工程学院,扬州225127 [2]河北师范大学中燃工学院,石家庄050024 [3]东南大学能源热转换及其过程测控教育部重点实验室,南京210096

出　　处：《东南大学学报（自然科学版）》2020年第3期516-521,共6页Journal of Southeast University：Natural Science Edition

基　　金：国家自然科学基金资助项目(51576043).

摘　　要：考虑到液滴在纤维上的附着形态是滤网运行压降的重要影响因素,为探究油颗粒在纤维上的附着形貌,采用数学模型和数值模拟方法,对液滴附着形貌的几何特征参数进行预测计算.基于平面弯曲思路提出了蛤壳状数学模型,并采用有限元软件对蛤壳状数学模型和现有的梭状数学模型的精度进行验证.通过有限元软件和数学模型计算获得蛤壳状和梭状2种附着形貌的分界以及无量纲液滴体积和接触角对附着形貌几何特征的影响.结果表明,随着接触角的增加,液滴在一定直径的纤维上形成梭状所需的体积呈指数增加;在接触角θ>10°和无量纲液滴体积不大于3时,蛤壳状数学模型的计算误差小于10%;接触角减小时润湿长度和自由表面增加,纤维和油颗粒的碰撞和接触几率增加;无量纲体积越小的液滴演变成液桥或液膜的几率越小.Considering that the adhesion shape of liquid droplets on the fiber is an important factor to affect the operating pressure drop of the filter,to explore the adhesion shape of oil droplets on the fiber,the geometrical characteristic parameters of the droplet adhesion shape were predicted and calculated by a mathematical model and numerical simulation.A clamshell mathematical model based on plane bending was proposed.The finite element software was used to verify the accuracy of the clamshell mathematical model and the existing barrel mathematical model.The boundary of clamshell and barrel adhesion shapes and the influences of dimensionless droplet volume and contact angle on the geometric characteristics of adhesion shape were obtained by the finite element software and the mathematical model.The results show that as the contact angle increases,the volume required for the barrel shape forming by the droplet on a certain diameter fiber increases exponentially.When the contact angleθ>10°and the dimensionless droplet volume is not greater than 3,the computational error of the clamshell mathematical model is less than 10%.When the contact angle decreases,the wetting length and the free surface area increase,and the chances of collision and contact between fibers and oil droplets increase.The smaller the dimensionless droplet,the less probability that the droplet is to evolve into liquid bridge or film.

关 键 词：数学模型 液滴形貌 梭状 蛤壳状 几何特征 

分 类 号：X513[环境科学与工程—环境工程]