The transport coefficients described in the dense gas-like model

The transport coefficients of shear viscosity, diffusion, thermal conductivity and bulk viscosity are described systematically in the dense gas-like model that adopts the concepts of both the kinetic theory and the reaction rate theory. The activation energy is assumed to be the sum of the excess energy and the excess pressure with the fraction 1/3 fc, where the factor of three represents the kinetic freedom of a point particle, and fc its deviation in a fluid. Analyzing the simulation data for the hard-sphere and Lennard–Jones fluids, the form of fc is prescribed as a simple function of density and temperature with three parameters for each transport coefficient, and these parameters are sought by fitting the simulation data. In addition, a term is implemented in fc so as to describe the anomaly experimentally observed for the thermal conductivity as well as for the bulk viscosity of the Ar fluid near the critical point. The form of this term is adopted from the cubic model that has been frequently employed to describe the static critical anomalies. The physical properties as well as the dynamic processes of a fluid are featured in fc that may indicate signals of the anomaly near the critical point by the analysis of the simulation data.