The Thermal Conductivity of Argon, Nitrogen and Carbon Monoxide in the Temperature Range 300 — 430 K at Pressures up to 10 MPa

Measurements of the thermal conductivity of argon, nitrogen and carbon monoxide have been carried out over the temperature range 300 – 430 K and at pressures up to 10 MPa in a transient hot‐wire apparatus. The measurements on argon confirm that the accuracy of the experimental results is one of ± 0.3%. Substantial differences have been found between the thermal conductivity of nitrogen and carbon monoxide in the limit of zero density. This observation can only be satisfactorily explained by the existence of large differences between the diffusion coefficients for internal energy for the two gases. In turn these results indicate that this functional of the intermolecular pair potential may be particularly sensitive to its non‐spherical part. – At elevated densities the temperature independence of the excess thermal conductivity as a function of density is confirmed to a high degree of precision.