Soft Matter and Complex Systems Seminar

Many studies attribute the evolution of droplet size distribution in warm, convective clouds to enhancement of collision-coalescence by turbulence. One of the effects of turbulence on droplets is preferential concentration. In order to analyze one of mechanisms leading to preferential concentration we investigate motion of droplets, governed by viscosity and gravity only, in prescribed line and Burgers vortices. Such vortices are often considered reasonable models of thin and long vortex tubes present in high Reynolds number turbulence. Both analytical and numerical solutions of droplet motion allow to identify stationary points, stationary orbits and limit cycles, which influence spatial distribution of droplets and effectively sort polydysperse particles.