Example: calculation of viscosity and thermal conductivity for a dissociated CO2 gas mixture
Transport coefficients were calculated for the case of LTE reacting CO2 mixture (CO2, CO, O2, O, C) at pressure P=1 atm in the temperature range 300≤T≤4000 K. The following parameters for Lennard-Jones potential were used:
CO2-CO2: e/k= 216 K, d= 3.87 Angstrom; O2-O2: e/k= 107 K, d= 3.47 Angstrom;
CO-CO: e/k= 100 K, d= 3.71 Angstrom; O-O: e/k= 107 K, d= 3.05 Angstrom;
C-C: e/k= 31 K, d= 3.39 Angstrom.
The necessary non-diagonal values eij and dij were calculated using the conventional combination rules. Transport coefficients were calculated using the accurate formulae of the Chapman-Enskog method with account for higher approximations, e.g. x=2 for viscosity, x=4 for translational thermal conductivity.
In figures (a) and (b) the calculated (a) viscosity and (b) total thermal conductivity l=ltr+lint of CO2 are compared with the experimental and theoretical data. This comparison indicates that the results of calculations are accurate to within about 1.4% for T≤2000 K, the uncertainty is of 7% at T=3000 K and 17% at T=4000 K because of the use of the Lennard-Jones potential for all pairs of particles.