|
|
|
MOLECULAR DYNAMICS SIMULATION OF DIFFUSION IN GASES AND LIQUIDS
Kharlamov G.V., Zhilkin S.V.
Novosibirsk State Technical University, Novosibirsk, Russia
|
Citation:
Kharlamov, G.V. and Zhilkin, S.V., (2014) Molecular dynamics simulation of diffusion in gases and liquids, Modern Science: Researches, Ideas, Results, Technologies, Iss. #1(14), PP. 51 - 54.
|
|
Keywords:self-diffusion; molecular dynamics; phase transition; velocity autocorrelation function |
|
Abstracts:
The results of the velocity autocorrelation functions and self-diffusion coefficients calculations for Lennard - Jones molecular systems by molecular dynamics method in a wide range of densities and temperatures are presented. The universal self-diffusion dependence on density for homogeneous systems was observed. Various heterogeneous phase structures of the systems with vapor-liquid phase transition are discovered and investigated. There are clusters and nanodroplets in gas, nanobubbles in liquid, the system separation in liquid layer and vapor layer. The self-diffusion coefficients for these systems deviate from the universal dependence for homogeneous systems. Besides, an anomalous increasing of the self-diffusion coefficient with increasing of the system density can be observed.
The velocity autocorrelation functions have a complicated character and are defined by diffusion mechanisms as in homogeneous systems as in heterogeneous phase molecular structures. |
|
References:
Meier K., Laesecke A., Kabelac S. Transport coefficients of the Lennard-Jones model fluid. II Self-diffusion // J. Chem . Phys. 2004. Vol. 121. 9526. Heyes D.M. Transport coefficients of Lennard-Jones Fluids: A molecular-dynamics and effective-hard-sphere treatment // Phys. Rev. B 1988. Vol. 37. № 10. P. 5677 - 5696. Liu H., Silva C.M., Macedo E.A. Unified approach to the self-diffusion coefficients of dense fluids over wide ranges of temperature and pressure - hard-sphere, square-well, Lennard-Jones and real substances // Chemical Engineering Science, 1998. Vol. 53. № 13. P. 2403-2422. Laghaei R., Nasrabad A.E., Eu B.C. Excluded volume in the generic van der Waals equation of state and the self-diffusion coefficient of the Lennard-Jones fluid // J. Chem . Phys. 2006. Vol. 124. 154502. Dyer K.M., Pettitt B.M., Stell G.. Systematic investigation of theories of transport in the Lennard-Jones fluid // J. Chem . Phys. 2007. Vol. 126. 034502. Yamaguchi T., Kimura Y., Hirota N. Molecular dynamics simulation of solute diffusion in Lennard-Jones fluids // Molecular Physics. 1998. Vol. 94. № 3. P. 527-537. Hirschfelder J.O., Curtiss C.E., Bird R.B. Molecular theory of gases and liquids. Wiley, New York, 1964. Русский перевод:
|
|
|
