The thermodiffusive behavior of a Lennard-Jones binary mixture has been studied by using nonequilibrium molecular dynamics. In particular, the dependence of the Soret coefficient, ST, on the temperature and composition has been investigated, exploring a wide range of temperatures from 1000 K to the condensation temperature of the mixture. In a previous paper the dependence of ST on the temperature and the composition was studied for Lennard-Jones binary mixtures presenting mixing/demixing (consolute) phase transition, and the results allowed the formulation of a very simple expression with the computed values of ST in the one phase region outside the critical region closely fitted by the function [T − Tc(x1)]−1, with Tc(x1) the demixing temperature of the mixture under study. The results of the present work show that the same expression of ST can be found for the one phase region outside the evaporation/condensation region but now with Tc representing the condensation temperature of the mixture under study.
Temperature and composition dependence of the Soret coefficient in Lennard-Jones mixtures presenting evaporation/condensation phase transition
ANGELI, Celestino
2011
Abstract
The thermodiffusive behavior of a Lennard-Jones binary mixture has been studied by using nonequilibrium molecular dynamics. In particular, the dependence of the Soret coefficient, ST, on the temperature and composition has been investigated, exploring a wide range of temperatures from 1000 K to the condensation temperature of the mixture. In a previous paper the dependence of ST on the temperature and the composition was studied for Lennard-Jones binary mixtures presenting mixing/demixing (consolute) phase transition, and the results allowed the formulation of a very simple expression with the computed values of ST in the one phase region outside the critical region closely fitted by the function [T − Tc(x1)]−1, with Tc(x1) the demixing temperature of the mixture under study. The results of the present work show that the same expression of ST can be found for the one phase region outside the evaporation/condensation region but now with Tc representing the condensation temperature of the mixture under study.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
