Chapman-Enskog Solution Research Articles

Transport Coefficients in Moderately Dense Gases

The first virial corrections for shear viscosity η and thermal conductivity λ are calculated, starting from the BOLTZMANN-LANDAU equation of a quantum gas in binary collision approximation. The first order CHAPMAN-ENSKOG solution is used. With a very simplified collisional operator numerical values are got and compared with experiments. The result is that the kinetic equation including the interaction effects in quasi-free motion is able to explain the empirical order of magnitude of dη/dn.

Viscosity of Partially Ionized Gaseous Cesium

The Chapman-Enskog solution of the Boltzmann equation is used to obtain theoretical data for the viscosity of gaseous cesium, including the effects of up to 10% ionization. Results are presented for the viscosity of ionized cesium at pressures of 10−2, 10−3, 10−4, and 10−5 atm in the temperature range 1000°–3500°K, and for unionized cesium over the same range. The viscosity of the 10% ionized gas is found to be about 20% lower than that of unionized cesium under the same conditions.