J. Luettmerstrathmann et al., NONASYMPTOTIC CRITICAL-BEHAVIOR OF THE TRANSPORT-PROPERTIES OF FLUIDS, The Journal of chemical physics, 103(17), 1995, pp. 7482-7501
We extend the application of the mode-coupling theory for the dynamics
of critical fluctuations in fluids into the non-asymptotic critical r
egion. An approximate solution bf the mode-coupling equations yields a
set of representative equations for the thermal conductivity and the
viscosity of one-component fluids which incorporates the crossover fro
m asymptotic singular behavior near the critical point to the regular
behavior of these transport properties far away from the critical poin
t. The equations for the critical enhancements of the thermal conducti
vity and the viscosity depend on the background transport properties o
f the fluid, the equilibrium thermodynamic properties of the fluid, an
d one fluid-dependent wave-number cutoff q(D), which is indicative of
the crossover length scale. We compare our crossover model with experi
mental data for the thermal diffusivity, the thermal conductivity, and
the viscosity of carbon dioxide and ethane. (C) 1995 American Institu
te of Physics.