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Stable simulation of fluid flow with high-Reynolds number using Ehrenfests steps

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 Added by Robert Brownlee
 Publication date 2007
  fields Physics
and research's language is English




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The Navier--Stokes equations arise naturally as a result of Ehrenfests coarse-graining in phase space after a period of free-flight dynamics. This point of view allows for a very flexible approach to the simulation of fluid flow for high-Reynolds number. We construct regularisers for lattice Boltzmann computational models. These regularisers are based on Ehrenfests coarse-graining idea and could be applied to schemes with either entropic or non-entropic quasiequilibria. We give a numerical scheme which gives good results for the standard test cases of the shock tube and the flow past a square cylinder.



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