Reversible Viscosity and Navier–Stokes Fluids

@article{Gallavotti2019ReversibleVA,
  title={Reversible Viscosity and Navier–Stokes Fluids},
  author={Giovanni Gallavotti},
  journal={Stochastic Dynamics Out of Equilibrium},
  year={2019}
}
  • G. Gallavotti
  • Published 12 June 2017
  • Physics
  • Stochastic Dynamics Out of Equilibrium
Exploring the possibility of describing a fluid flow via a time-reversible equation and its relevance for the fluctuations statistics in stationary turbulent (or laminar) incompressible Navier-Stokes flows. 

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: Viscosity, as a physical property of fluids, re-flects an average effect over a chaotic microscopic motion described by Hamiltonian equations. It is proposed, as an example, that stationary states of

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  • G. Gallavotti
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  • 2021
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Ensembles, turbulence and fluctuation theorem

  • G. Gallavotti
  • Physics
    The European physical journal. E, Soft matter
  • 2020
The paradigmatic example of irreversible evolution, the 2D Navier-Stokes incompressible flow is considered, to show how universal properties of fluctuations in systems evolving irreversibily could be predicted in a general context.

Navier-Stokes and equivalence conjectures

: General considerations on the Equivalence conjectures and a review of few mathematical results.

Equivalence of nonequilibrium ensembles in turbulence models.

The equivalence of reversible and irreversible ensembles for the case of a multiscale shell model of turbulence is tested and it is verified that the equivalence is obeyed for the mean values of macroscopic observables, up to an error that vanishes as the system becomes more and more chaotic.

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