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RESEARCH PRODUCT
Relative importance of second-order terms in relativistic dissipative fluid dynamics
Harri NiemiHarri NiemiDirk H. RischkeEtele MolnárGabriel S. Denicolsubject
PhysicsNuclear and High Energy PhysicsNuclear Theoryta114Lattice Boltzmann methodsFluid Dynamics (physics.flu-dyn)Reynolds numberFOS: Physical sciencesPhysics - Fluid DynamicsNonlinear Sciences::Cellular Automata and Lattice GasesBoltzmann equationPhysics::Fluid DynamicsNuclear Theory (nucl-th)High Energy Physics - Phenomenologysymbols.namesakeClassical mechanicsHigh Energy Physics - Phenomenology (hep-ph)Boltzmann constantsymbolsDissipative systemFluid dynamicsKnudsen numberDirect simulation Monte Carlodescription
In Denicol et al., Phys. Rev. D 85, 114047 (2012), the equations of motion of relativistic dissipative fluid dynamics were derived from the relativistic Boltzmann equation. These equations contain a multitude of terms of second order in Knudsen number, in inverse Reynolds number, or their product. Terms of second order in Knudsen number give rise to non-hyperbolic (and thus acausal) behavior and must be neglected in (numerical) solutions of relativistic dissipative fluid dynamics. The coefficients of the terms which are of the order of the product of Knudsen and inverse Reynolds numbers have been explicitly computed in the above reference, in the limit of a massless Boltzmann gas. Terms of second order in inverse Reynolds number arise from the collision term in the Boltzmann equation, upon expansion to second order in deviations from the single-particle distribution function in local thermodynamical equilibrium. In this work, we compute these second-order terms for a massless Boltzmann gas with constant scattering cross section. Consequently, we assess their relative importance in comparison to the terms which are of the order of the product of Knudsen and inverse Reynolds numbers.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2013-08-04 | Physical Review D |