Hydrodynamics of a drying multicomponent liquid droplet

Using microscopy methods on light and dark fields, the flow patterns developing in drying droplets of pure transparent liquids, solutions, and suspensions of micro- and nanoparticles are investigated. The flow patterns inside drying droplets of real, colloid, and mixed solutions containing nanoand microparticles-markers are studied by means of video and photo registration of microscopic images. The analysis of particle displacements indicates the existence of a global convective flow which forms a toroidal circulation with an ascending jet at the droplet center. The typical types of the structures depending on the droplet composition are distinguished. It is shown that the intensity of the flow inside the droplet affects the surface convection. The effect of the hydrodynamic flow on the transport of a substance, forming the dry-deposit texture, is studied.