Transport coefficients of helium and argon-helium plasmas

Calculated values of the viscosity, thermal conductivity, and electrical conductivity of helium, and mixtures of argon and helium, at high temperatures are presented. In addition, combined ordinary, pressure, and thermal diffusion coefficients are given for the mixtures. The calculations, which assume local thermodynamic equilibrium, are performed for atmospheric pressure plasmas in the temperature range from 300 to 30000 K. The results are compared with those of previously published studies. Significant discrepancies are found; these are attributed to the improved values of the collision integrals used here in calculating the transport coefficients.