Transport coefficients of soft sphere fluid at high densities
Yu. D. Fomin, V. V. Brazhkin, V. N. Ryzhov
Institute for High Pressure Physics RAS, 142190 Troitsk, Russia
Molecular dynamics computer simulation has been used to
compute in wide pressure-temperature region the self-diffusion
coefficient and shear viscosity of soft-sphere fluids, in which
the particles interact through the inverse power pair potential.
The limitations of the previous empirical approaches and models
for the description of the kinetic coefficients is shown. On the
basis of the simulations the universal functions for diffusion
coefficient and shear viscosity of soft spheres are constructed
which allow to compute these quantities for any density and
temperature. We show that the behavior of shear viscosity at high
temperatures is more complex than the one of diffusion coefficient
and give quantitative explanation of this result.