Inverse Chapman-Enskog Derivation of the Thermohydrodynamic Lattice-BGK Model for the Ideal Gas

Details Inverse Chapman-Enskog Derivation of the Thermohydrodynamic Lattice-BGK Model for the Ideal Gas Inverse Chapman-Enskog Derivation of the Thermohydrodynamic Lattice-BGK Model for the Ideal Gas

1998-10-13

arxiv.org/abs/comp-gas/9810001v1

Physics

Condensed Matter

Statistical Mechanics

12 pages, no figures, RevTeX

Scientific paper

A thermohydrodynamic lattice-BGK model for the ideal gas was derived by Alexander et al. in 1993, and generalized by McNamara et al. in the same year. In these works, particular forms for the equilibrium distribution function and the transport coefficients were posited and shown to work, thereby establishing the sufficiency of the model. In this paper, we rederive the model from a minimal set of assumptions, and thereby show that the forms assumed for the shear and bulk viscosities are also necessary, but that the form assumed for the thermal conductivity is not. We derive the most general form allowable for the thermal conductivity, and the concomitant generalization of the equilibrium distribution. In this way, we show that it is possible to achieve variable (albeit density-dependent) Prandtl number even within a single-relaxation-time lattice-BGK model. We accomplish this by demanding analyticity of the third moments and traces of the fourth moments of the equilibrium distribution function. The method of derivation demonstrates that certain undesirable features of the model -- such as the unphysical dependence of the viscosity coefficients on temperature -- cannot be corrected within the scope of lattice-BGK models with constant relaxation time.

Affiliated with

Also associated with

No associations

Rating

Inverse Chapman-Enskog Derivation of the Thermohydrodynamic Lattice-BGK Model for the Ideal Gas does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Inverse Chapman-Enskog Derivation of the Thermohydrodynamic Lattice-BGK Model for the Ideal Gas, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Inverse Chapman-Enskog Derivation of the Thermohydrodynamic Lattice-BGK Model for the Ideal Gas will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-619365