Moment Equations for Polyatomic Gases

Abstract

© 2014, Springer Science+Business Media Dordrecht. The aim of this paper is to analyze the moment equations for polyatomic gases whose internal degrees of freedom are modeled by a continuous internal energy function. The closure problem is resolved using the maximum entropy principle. The macroscopic equations are divided in two hierarchies—“momentum” and “energy” one. As an example, the system of 14 moments equations is studied. The main new result is determination of the production terms which contain two parameters. They can be adapted to fit the expected values of Prandtl number and/or temperature dependence of the viscosity. The ratios of relaxation times are also discussed.