Relaxation of a steep density gradient in a simple fluid: comparison between atomistic and continuum modeling
Abstract
We compare dynamical nonequilibrium molecular dynamics and continuum simulations of the dynamics of relaxation of a fluid system characterized by a non uniform density profile. Results match quite well as long as the lengthscale of density nonuniformities are greater than the molecular scale (10 times the molecular size). In presence of molecular scale features some of the continuum fields (e.g. density and momentum) are in good agreement with atomistic counterparts, but are smoother. On the contrary, other fields, such at the temperature field, present very large difference with respect to reference (atomistic) ones. This is due to the limited accuracy of some of the empirical relations used in continuum models, the equation of state of the fluid in the example considered.
Cite
@article{arxiv.1407.6302,
title = {Relaxation of a steep density gradient in a simple fluid: comparison between atomistic and continuum modeling},
author = {Meisam Pourali and Simone Meloni and Francesco Magaletti and Ali Maghari and Carlo Massimo Casciola and Giovanni Ciccotti},
journal= {arXiv preprint arXiv:1407.6302},
year = {2015}
}