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 flowsand 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 dropletsin vitro or inside cells .
We study the hydrodynamics and shape changes of chemically active droplets. In non-spherical droplets, surface tension generates hydrodynamic flows that drive liquid droplets into a spherical shape. Here we show that spherical droplets that are maintained away from thermodynamic equilibrium by chemical reactions may not remain spherical but can undergo a shape instability which can lead to spontaneous droplet division. In this case chemical activity acts against surface tension and tension-induced hydrodynamic flows. By combining low Reynolds-number hydrodynamics with phase separation dynamics and chemical reaction kinetics we determine stability diagrams of spherical droplets as a function of dimensionless viscosity and reaction parameters. We determine concentration and flow fields inside and outside the droplets during shape changes and division. Our work shows that hydrodynamic flows tends to stabilize spherical shapes but that droplet division occurs for sufficiently strong chemical driving, sufficiently large droplet viscosity or sufficiently small surface tension. Active droplets could provide simple models for prebiotic protocells that are able to proliferate. Our work captures the key hydrodynamics of droplet division that could be observable in chemically active colloidal droplets .
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Droplets that are driven away from thermal
We study the hydrodynamics and shape changes of chemically active droplets. In non-spherical droplets, surface tension generates hydrodynamic flows that drive liquid droplets into a spherical shape. Here we show that spherical droplets that are maintained away from thermodynamic
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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
may not remain spherical but can undergo a shape instability which can lead to spontaneous
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We solve the reaction diffusion equations of a phase separating system coupled to hydrodynamic flowsand
In this case chemical activity acts against surface tension and tension-induced hydrodynamic flows. By combining low Reynolds-number hydrodynamics with phase separation dynamics and chemical reaction kinetics we
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spherical
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show that hydrodynamics
determine concentration and flow fields inside and outside the droplets during shape changes and division. Our work shows that hydrodynamic flows
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droplets
shapes
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Our work suggests that chemically driven droplet division
Active droplets could provide simple models for prebiotic protocells that are able to proliferate. Our work captures the key hydrodynamics of droplet division that
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soft colloidal systems with low surface tension such as RNA-protein dropletsin vitro or inside cells
chemically active colloidal droplets