Transport Coefficients of Partially Ionized Argon

The complete Chapman‐Enskog‐Burnett expressions for the transport coefficients of multicomponent gas mixtures are applied to the computation of the properties of partially ionized argon. Studies of the rate of convergence of the approximations to the coefficients show that the third approximation to the thermal conductivity and the second to the viscosity are adequate at all degrees of ionization. The ordinary ambipolar diffusion coefficient is given to excellent accuracy by twice the binary ion‐atom diffusion coefficient but, at low ionization, apparently not even the fourth approximation to the electrical conductivity has converged to the true value. The computed electrical and thermal conductivities are compared with experimental measurements.