High-pressure viscosity behaviour of the tridecane +1-methylnaphthalene system
Pierre Daugé, Antoine Baylaucq, Christian Boned
The dynamic viscosity, η, and the density, ρ, of binary mixtures of tridecane + 1-methylnaphthalene, described by nine molar fractions (0, 0.125, 0.250, 0.375, 0.500, 0.625, 0.750, 0.875, 1), were measured in the temperature range 293.15 – 353.15 K, in progressive 10 K steps, at pressures 0.1, 20, 40, 60, 80, and 100 MPa for the dynamic viscosity, and at pressures from 0.1 MPa to 65 MPa in progressive 5 MPa steps for the density. The whole set of experimental data represents 378 points for the dynamic viscosity and 882 for the density. The measurements of η allow determination of the excess viscosity, ηE, and the excess activation energy of flow, ΔGE, versus pressure, temperature, and composition. Some simple mixing rules are tested in order to analyse the possibility of estimating the viscosity of a mixture with knowledge only of the pure substances.