After a quench, a mixture can separate spontaneously into two phases, this process, known as spinodal decomposition leads to the formation of patterns with a characteristic lengthscale that is due to the balance between the diffusion process that is efficient at small lengthscale and the thermodynamic of the system that favors large lengthscale structures (because surface energy is then smaller).
After the initial phase separation, this microstructure evolves either because of diffusion or because of fluid flow. In both cases the characteristic lengthscale of the pattern increases so that the surface energy decreases.
We have studied the effects of the respective viscosities of the two phases on this coarsening process and on the geometrical characteristic of the microstructure.
Images of the interfaces between the two phases for a mixture where the volume fraction of the minority phase id 0.35 and where the viscosity of the minority phase with respect to the majority phase is increasing |
Reference
[1]Hervé Henry, György Tegze On self similarity and coarsening rate of a convecting bicontinuous phase separating mixture : effect of the viscosity contrast Phys. Rev. Fluids 3, 074306 (2018) ARXIV PRFluids