Spinodal Decomposition in Binary Gases

نویسنده

  • S. Bastea
چکیده

We carried out three-dimensional simulations, with about 1.4 × 10 particles, of phase segregation in a low density binary fluid mixture, described mesoscopically by energy and momentum conserving Boltzmann-Vlasov equations. Using a combination of Direct Simulation Monte Carlo(DSMC) for the short range collisions and a version of Particle-In-Cell(PIC) evolution for the smooth long range interaction, we found dynamical scaling after the ratio of the interface thickness(whose shape is described approximately by a hyperbolic tangent profile) to the domain size is less than ∼ 0.1. The scaling length R(t) grows at late times like t, with α = 1 for critical quenches and α = 1 3 for off-critical ones. We also measured the variation of temperature, total particle density and hydrodynamic velocity during the segregation process. PACS numbers: 64.75.+g, 68.10.-m, 47.70.Nd Typeset using REVTEX

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تاریخ انتشار 1997