초록 |
During droplet evaporation, the evaporation induced-flows inside the droplet play an important role to determine the solute deposit patterns after the evaporation. Particularly, the controlling of the solute assembly inside the evaporating droplet is regarded as an emerging issue to enhance the functionality of the solute in the ink-jet printing technology. Therefore, various analytical and numerical studies have been conducted to estimate the flow fields in the droplets. Here, we report a new and simple experimental method which is the laser absorbance monitoring system to estimate the flow direction inside an evaporating droplet. By using the laser absorbance monitoring system, the concentration changes at the center of the evaporating droplets are successfully monitored, and the flow directions are estimated with a variation of the initial contact angles. |