Reversibility, Irreversibility, Friction and nonequilibrium ensembles in N-S equations

TL;DR

This paper explores the analogy between nonequilibrium fluid states governed by Navier-Stokes equations and statistical ensembles, focusing on reversibility, irreversibility, and friction effects in chaotic microscopic dynamics.

Contribution

It introduces a framework for describing stationary states of fluids under constant force using ensemble concepts similar to equilibrium statistical mechanics.

Findings

Stationary fluid states can be modeled with ensemble approaches.

Friction and irreversibility are linked to microscopic chaotic motion.

Analogies between nonequilibrium fluid dynamics and statistical mechanics are established.

Abstract

Viscosity, as a physical property of fluids, reflects an average effect over a chaotic microscopic motion described by Hamiltonian equations. It is proposed, as an example, that stationary states of an incompressible fluid subject to a constant force, can be described via several ensembles, in strict analogy with equilibrium Statistcal Mechanics.