液滴平壁铺展过程分析  

Analysis of Spreading Process of Droplet on Flat Surface

作　　者：魏明锐[1] 刘明嘉[1] 颜伏伍[1] 刘元[1] 许伟康[1] 

机构地区：[1]武汉理工大学汽车工程学院,湖北武汉430070

出　　处：《内燃机学报》2012年第6期538-543,共6页Transactions of Csice

基　　金：国家自然科学基金资助项目(51276132)

摘　　要：液滴撞击壁面后的铺展行为是液滴撞壁的主要发展模式之一,对喷雾研究具有重要意义.通过对理想光滑壁面和实际粗糙壁面接触角的理论分析,发现壁面粗糙度是引起接触角滞后的主要原因,通过引入壁面阻力建立了粗糙壁面上接触角滞后模型.对接触线附近贴壁区域的流动状态进行分析,引入接触线特征参数求得固液间的黏性剪切力和气液界面上的黏性剪切力.在理论分析的基础上建立了动态接触角随接触线移动速度的变化关系式.通过研究动态接触角随接触线特征参数、液滴黏度、壁面粗糙度和气液表面张力的变化关系,获得了这些因素对液滴碰壁铺展行为的影响规律.Spreading behavior of droplets is one mode of developing wall impinged droplet. Through ana- lyzing thee contacting angle of ideal wall and actual wall, it is found that the contacting angle hysteresis is mainly caused by wall roughness. A contacting angle hysteresis model was build up by introducing wall resistance. Relationship between dynamic contacting angle and moving speed of contacting line was estab- lished based on theoretical analysis. The model is validated. Through analyzing the characteristic parame- ters of contacting line, droplet viscosity, gas-liquid surface tension, wall roughness during droplet spreading and retraction processes, their effects on spray droplets were clarified.

关 键 词：液滴 铺展 动态接触角 

分 类 号：TK402[动力工程及工程热物理—动力机械及工程]