The rotational relaxation time and transport coefficients in a diatomic gas
Abstract
The rotational relaxation time and the coefficients of shear viscosity and heat conduction of rotationally excited nitrogen are calculated for the temperature range 300-10,000 K. The rotational relaxation time is calculated using both the Chapman-Enskog method and the relaxation equation. The problem of translational and rotational energy redistribution is solved analytically for the short-range part of the Parker model potential; the effect of the long-range part of the potential is allowed for by means of a correction. The accuracy of the approximate expression of Eucken and that of Mason and Monchik (1962) is evaluated. It is shown that the accuracy of the approximate calculations of the rotational relaxation time can be significantly improved by introducing a two-parameter term which additionally depends on a parameter characterizing the initial rotational state distribution.
- Publication:
-
PMTF Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki
- Pub Date:
- August 1983
- Bibcode:
- 1983PMTF.........3L
- Keywords:
-
- Diatomic Gases;
- Gas Transport;
- High Temperature Gases;
- Molecular Relaxation;
- Molecular Rotation;
- Relaxation Time;
- Chapman-Enskog Theory;
- Gas Viscosity;
- Molecular Energy Levels;
- Nitrogen;
- Thermal Conductivity;
- Transport Properties;
- Thermodynamics and Statistical Physics