TRANSPORT-PROPERTIES OF DENSE FLUIDS VIA SPHERICAL-MODELS OF THE INTERACTION POTENTIAL

The method for evaluation of the dense fluid viscosity and thermal conductivity (translational part) from intermolecular interaction information is derived on the basis of the local similarity principle. The non-equilibrium criteria of mapping a real-system interaction function U(r)(R) to the reference Van der Waals Potential U(b)(R, A) are formulated first. Then the density dependence for the kinetic effective hard-sphere diameter is studied. The test of the proposed approach has been carried out for a number of spherical potential models (Ne-Ne, Ar-Ar, Kr-Kr, Xe-Xe, CO2-CO2, N2-N2, O2-O2) in the range of the reduced densities 0.4 < n-sigma-3 < 1 and temperatures 0.9 < kT/epsilon < 20. A comparison of the evaluated values of the viscosity eta and thermal conductivity lambda with the empirical data has shown the reliability of the suggested approach in application to spherical and weakly anisotropic molecular systems: the mean discrepancies delta-eta and delta-lambda usually in the range of 3-5%.