液滴融合前的微小液滴行为研究

通过微观可视化实验研究两个主液滴(水滴)在水平均质表面的融合,发现在液滴融合之前两个主液滴中间有规律地分布着大量微小液滴,这些微小液滴相互之间会吸附合并,且主液滴会吸附边界附近的微小液滴。分析微小液滴的产生条件和分布规律,结果表明:微小液滴只在两个主液滴相互靠近的中间区域产生,两个主液滴之间的边界距离越大,微小液滴的尺寸越小,且微小液滴在中间区域的尺寸分布近似对数正太分布。因为有微小液滴的生成和合并以及主液滴对微小液滴的吸附合并,固体表面对主液滴界面移动的阻力减小,且主液滴界面会由于吸附边界附近的微小液滴而发生振荡,进而促进主液滴的边界阶梯式地移动。

Research on Micro-droplets Behavior before the Coalescence of the Two Main Droplets

In the visible experiments of coalescence between two main droplets in the horizontal homogeneous surface, plentiful micro-droplets were found distributing regularly in the intermediate region of the two main droplets before the coalescence. These micro-droplets can absorb and coalesce with each other, at the same time, the main droplets can absorb the micro-droplets near the main droplets boundary. Analyzing the conditions and the distribution of these micro-droplets, the results show that the micro-droplets only appeared in the intermediate region of the two main-droplets. The greater the distances between the two main droplets are, the smaller the sizes of the micro-droplets are. And the micro-droplets size distribution is approximate to Log-normal distribution. Because of the formation and coalescence of these micro-droplets and the main droplets absorbing the micro-droplets, the resistance of the horizontal homogeneous surface to the main droplets interface movement was reduced, and the interface of the two main droplets oscillated since the absorption of these micro-droplets. Thereby, the movement of the droplets boundary were promoted. The two main droplets interfaces no longer moved slowly and continuously, but advanced increasingly.