arXiv subjects

M. Kroger

Publications and source records attributed to M. Kroger.

4 recordsLinked to original sources

arXiv2009

Boltzmann equation and hydrodynamic fluctuations

We apply the method of invariant manifolds to derive equations of generalized hydrodynamics from the linearized Boltzmann equation and determine exact transport coefficients, obeying Green-Kubo formulas. Numerical calculations are performed in the special case of Maxwell molecules. We investigate, through the comparison with experimental data and former approaches, the spectrum of density fluctuations and address the regime of finite Knudsen numbers and finite frequencies hydrodynamics.

cond-mat.stat-mech↗

arXiv2008

Exact linear hydrodynamics from the Boltzmann equation

Exact (to all orders in Knudsen number) equations of linear hydrodynamics are derived from the Boltzmann kinetic equation with the Bhatnagar-Gross-Krook collision integral. The exact hydrodynamic equations are cast in a form which allows us to immediately prove their hyperbolicity, stability, and existence of an H-theorem.

cond-mat.stat-mech↗

arXiv2007

Hyperbolicity of exact hydrodynamics for three-dimensional linearized Grad's equations

We extend a recent proof of hyperbolicity of the exact (to all orders in Knudsen number) linear hydrodynamic equations [M. Colangeli et al, Phys. Rev. E (2007), in press; arXiv:cond-mat/0703791v2] to the three-dimensional Grad's moment system. A proof of an H-theorem is also presented.

cond-mat.stat-mech↗

arXiv2007

From hyperbolic regularization to exact hydrodynamics for linearized Grad's equations

Inspired by a recent hyperbolic regularization of Burnett's hydrodynamic equations [A. Bobylev, J. Stat. Phys. 124, 371 (2006)], we introduce a method to derive hyperbolic equations of linear hydrodynamics to any desired accuracy in Knudsen number. The approach is based on a dynamic invariance principle which derives exact constitutive relations for the stress tensor and heat flux, and a transformation which renders the exact equations of hydrodynamics hyperbolic and stable. The method is described in detail for a simple kinetic model - a thirteen moment Grad system.

cond-mat.stat-mech↗