摘要
应用经典的Moffatt解,通过引入接触线特征参数λ给出接触线上的粘性剪切应力,导出动态接触角和接触线移动速度的关系,尝试解释文献中两种不同测量方法所得静态接触角不一致的现象,理论所揭示的动态接触角和接触线移动速度的关系曲线和以往文献中的曲线形式基本一致,通过和Hoffman试验数据的比较发现,λ与流体性质无关,是表征固壁性质的特征参数,并初步探讨了λ的数理意义。
On the basis of classical Moffatt's solution by introducing a characteristic parameter λ , the viscous shearing stress is obtained and the dependence of dynamic contact angle on the moving velocity of contact line is derived. The difference of the observation results from dynamical and statical methods, reported in literature [1], is explained clearly in the paper. In contrast, with Hoffman's experimental data, it is found that character parameter λ is solely dependent on solid wall property, but having no relation with liquid property. The introduction of the parameter λ is a complementarity to mere discussion of capillary number in previous literatures. True three-phase contact line slips on precursor film. The character parameter λ is dependent not only on the thickness of precursor film but also on the slip degree of the contact line on precursor film. The neglect of the existence of precursor film in classical fluid mechanical model results in stress singularity in the immediate vicinity of contact line.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2003年第3期472-474,共3页
Journal of Engineering Thermophysics
基金
国家自然科学基金资助项目(No.59976016)
国家"973"重大基础研究资助项目(No.G2000026301)
关键词
动态接触角
应力奇点
前驱膜
dynamic contact angle
stress singularity
precursor film
