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arXiv · 1009.3735

Phase separation of binary fluids with dynamic temperature

G. Gonnella·A. Lamura·A. Piscitelli·A. Tiribocchi
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Abstract

Phase separation of binary fluids quenched by contact with cold external walls is considered. Navier-Stokes, convection-diffusion, and energy equations are solved by lattice Boltzmann method coupled with finite-difference schemes. At high viscosity, different morphologies are observed by varying the thermal diffusivity. In the range of thermal diffusivities with domains growing parallel to the walls, temperature and phase separation fronts propagate towards the inner of the system with power-law behavior. At low viscosity hydrodynamics favors rounded shapes, and complex patterns with different lengthscales appear. Off-symmetrical systems behave similarly but with more ordered configurations.

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G. Gonnella, A. Lamura, A. Piscitelli, A. Tiribocchi. 2010-09-20. Phase separation of binary fluids with dynamic temperature. https://doi.org/10.1103/physreve.82.046302

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