The Gaussian-BGK model of Boltzmann equation with small Prandtl number
| Autor: | J. P. Perlat, Patrick Le Tallec, Benoît Perthame, Pierre Andries |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Physics
Internal energy Entropy (statistical thermodynamics) Gaussian Prandtl number General Physics and Astronomy 01 natural sciences Boltzmann equation 010305 fluids & plasmas Physics::Fluid Dynamics 010101 applied mathematics symbols.namesake Distribution function Phase space 0103 physical sciences symbols Statistical physics 0101 mathematics Navier–Stokes equations Mathematical Physics |
| Zdroj: | European Journal of Mechanics - B/Fluids. 19:813-830 |
| ISSN: | 0997-7546 |
| DOI: | 10.1016/s0997-7546(00)01103-1 |
| Popis: | In this paper we prove the entropy inequality for the Gaussian-BGK model of Boltzmann equation. This model, also called ellipsoidal statistical model, was introduced in order to fit realistic values of the transport coefficients (Prandtl number, second viscosity) in the Navier-Stokes approxima- tion, which cannot be achieved by the usual relaxation towards isotropic Maxwellians introduced in standard BGK models. Moreover, we introduce new entropic kinetic models for polyatomic gases which suppress the internal energy variable in the phase space by using two distribution functions (one for particles mass and one for their internal energy). This reduces the cost of their numerical solution while keeping a kinetic description well adapted to desequilibrium regions. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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