THERMAL-CONDUCTIVITY OF A MODERATELY DENSE GAS

Recent extensive measurements of the thermal conductivity of argon and nitrogen have enabled us to evaluate the first density correction as a function of temperature and to compare it with a theoretical prediction. The prediction follows from a previously published microscopically based theory, which includes effects due to collisional transfer, collisions among three molecules, and monomer-dimer collisions. The first density correction was evaluated for a Lennard-Jones interaction potential. An ad hoc modification of the theory accounts for contributions to the thermal conductivity from internal degrees of freedom. The comparison shows good agreement over a wide range of temperatures. © 1990.