Droplet formation in a thin layer of a two-component solution under the thermal action of laser radiation

Droplet growth in thin layers of water-alcohol solutions under the effect of a concentration-induced capillary flow, which is governed by a laser electromagnetic radiation, is investigated. It is established that an increase in water concentration in a solution accelerates the droplet growth. In low-concentrated solutions, a droplet may reach a quasi-steady state, in which its diameter is no larger than the diameter of the light beam projection onto the layer. A rise in the radiation power above an optimal magnitude decelerates the droplet growth. In low-concentrated solutions, this deceleration results from a decrease in the flow that feeds the droplet, while in high-concentrated solutions, it is due to a droplet constriction and an increase in its curvature radius.