摘要
水雾除尘效率来源于尘、雾颗粒之间的固-液动态相互作用,从细观角度出发,系统研究水雾液滴与尘堆表面之间的接触、碰撞行为规律。采用高速摄像、图像分析处理技术,从液滴行为、液滴接触角动态变化2个方面研究了液滴在尘堆表面的动态接触行为规律,并对比分析了液滴表面张力、黏度及尘堆粒径对动态接触行为影响的差异。结果表明,液滴在尘堆表面的动态接触行为分为碎裂直接铺展、回缩和回缩反弹3种模式,其接触模式主要取决于粉尘粒径、液滴黏度。在粒径不断减小的尘堆表面,相同理化性质的液滴的行为模式依次为碎裂直接铺展、回缩、回缩反弹。在保证液滴其他性质相同的条件下,增大液滴黏度会导致液滴回缩及回缩反弹行为模式在粉尘粒径较大的尘堆表面提前发生。伴随着液滴黏度增加或尘堆粒径减小,液滴在尘堆表面的接触角会发生动态波动,出现一定数量的波峰和波谷。
The dust removal efficiency of water mist depends on the solid-liquid dynamic interaction between dust and mist particles.From a mesoscopic perspective,the paper systematically studied the contact and collision behaviors between the water mist droplets and the surface of the dust pile.In this study,a high-speed camera was used to photograph the contact process between the droplet and the surface of the dust pile.Through observation and analysis of the photographs taken,the law of contact between the droplets and the surface of the dust pile is explored.This paper studied the dynamic contact behavior of liquid droplets on the surface of the dust pile from two aspects:behavior and dynamic changes of contact angle.In the research,the difference in the influence of droplet surface tension,viscosity,and dust particle size on dynamic contact behavior was compared and analyzed.The main conclusions drawn from this study are listed below.The dynamic contact behavior of droplets on the surface of the dust pile can be divided into three modes:fragmentation direct spreading,retracting,and retracting rebound.Droplets of the same physical and chemical properties will behave differently on the surface of the dust pile with decreasing particle size.In this case,the behavior mode sequence of the droplet is direct dispersal of damage,contraction,and rebound of contraction.Under the condition that the other properties of the droplets are the same,some new phenomena will appear when the viscosity of the droplets increases.These phenomena include droplet retraction and retraction rebound behavior patterns that occur in advance on the surface of dust piles with larger dust particles.As the viscosity of the droplets increases or the particle size of the dust pile decreases,the contact angle of the droplets on the surface of the dust pile dynamically fluctuates.These fluctuations can cause a certain number of peaks and troughs.
作者
李明
关子杰
LI Ming;GUAN Zi-jie(School of Resources and Safety Engineering,Central South University,Changsha 410013,China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2021年第6期2550-2556,共7页
Journal of Safety and Environment
基金
国家重点研发计划项目(2017YFC0805204,2018YFC0808404)
国家自然科学基金项目(51674289)
中南大学研究生自主探索创新项目(2020zzts719)。
关键词
职业卫生工程
水雾除尘
固液耦合
动态接触角
湿润性能
occupational health engineering
water mist dust removal
solid-liquid coupling
dynamic contact angle
wetting performance
