Role of hydrodynamic flows in chemically driven droplet division

Droplets that are driven away from thermal equilibrium by chemical reactions can exhibit rich dynamic behaviors. When droplet material turns over by chemical reactions a spherical droplet can become unstable and divide spontaneously. We study the effects of hydrodynamic flows in this droplet division. We solve the reaction diffusion equations of a phase separating system coupled to hydrodynamic flows and determine stability diagrams of droplets as a function of dimensionless viscosity and reaction parameters. We show that hydrodynamics tends to stabilize spherical droplets but that droplet division occurs for sufficiently strong chemical driving, sufficiently large droplet viscosity or sufficiently small surface tension. Our work suggests that chemically driven droplet division could be observable in soft colloidal systems with low surface tension such as RNA-protein droplets in vitro or inside cells.