接触角滞后现象的理论分析

通过引入“滞后阻力”的概念，分别用力学方法和热力学方法导出固体表面上液滴平衡时接触角应满足的条件；定性地给出了表面湿润性和前进接触角与后退接触角同表面粗糙度的关系，分析了前进接触角和后退接触角的物理意义；由此给出了接触角滞后现象的一种合理解释．本的研究为汽液相变传热过程中的沸腾核化、临界热负荷、最小热流密度、珠状凝结等现象的深刻认识，开拓了新的思路，传统研究中对粗糙度影响的复杂定量化测量描述也可转化为用接触角单一参数表征和描述的简化方法．因此本的认识对研究沸腾和凝结传热有重要的现实意义．

Hysteresis of Contact Angle at Liquid-solid Interface

A concept, resistance of liquid wetting solid surface, was introduced to investigate the contact angle characteristics of liquid touching solid surface in equilibrium. An expression and unified theory of liquid solid contact angle accounting for the resistance was theoretically obtained from mechanical and thermodynamic theory respectively, relating the wettability, advancing and receding contact angle with the roughness of the solid surface. This new approach provides a thoughtful understanding of the physical nature of advancing and receding contact angle and the contact angle hysteresis phenomenon. Using this theoretical evidence, some phase change transport phenomena such as boiling nucleation, critical heat flux, minimum heat flux and droplet condensation will be more intelligently described with a new discrimination. It is also possible to expose the effects of surface roughness on phase change heat transfer using a unique parameter, contact angle, other than the detail surface information.