J. Phys. Colloques
Volume 41, Numéro C9, Novembre 1980Third International Symposium on Gas-Flow and Chemical Lasers
|Page(s)||C9-225 - C9-230|
J. Phys. Colloques 41 (1980) C9-225-C9-230
ON ASYMPTOTIC SOLUTIONS OF DIATOMIC BOLTZMANN'S EQUATIONB. Zappoli
Société Européenne de Propulsion, B.P. N°37 - 33160 Saint Médard-en-Jalles, France.
Matched asymptotic expansion technics is used to derive the equations describing the hydro-dynamical behaviour of a diatomic gas. The vibrational relaxation phenomena appears to correspond to an inner asymptotic description, whereas the frozen and equilibrium cases correspond respectively to what has been called the first and second outer description. To illustrate these features, sound absorption due to vibrational relaxation is shown to correspond to the domain of non uniformity of a-straitforward small frequencies asymptotic expansion of the dispersion relation.