Efficient coalescence of two spreading drops

液滴聚结是两个可混溶的液滴在彼此靠近后的“传质”过程。这可以在自然过程（雨滴和露水的凝结）和人工工程过程（薄膜生长、喷墨印刷、喷涂等）中观察到。同时扩散的液滴的受控液滴聚结对于如上所述的许多应用是至关重要的方面。这种应用中的聚结动力学决定了两个铺展液滴之间的有效质量传递，铺展液滴的低效聚结可能导致几种不期望的效果，例如更长的印刷时间、印刷油墨的过度使用以及在喷洒农药或飞机除冰期间对环境有害的液体的浪费和溢出（高达~50%）。为了显著减少这种损失，在本研究计划中，提供了精确的方法来控制基板上的液滴聚结。

Liquid drop coalescence is a ‘mass transfer’ process between two miscible liquid drops after being brought in the vicinity of each other. This can be observed in both natural (rain drops and condensation of dew) and artificially engineered processes (film growth, inkjet printing, spraying, etc.). Controlled drop coalescence of simultaneously spreading drops is a crucial aspect for a number of applications as mentioned above. Coalescence dynamics in such applications dictates the efficient mass transfer between two spreading drops, and inefficient coalescence of spreading drops may result in several undesirable effects such as longer printing time, overuse of printing ink and wastage and spillage of environmentally hazardous liquids (up to ~50%) during spraying of pesticides or de-icing of planes. In order to significantly reduce such losses, in this research program the precise way to control the drop coalescence on the substrate is provided.