Fluctuation-induced pressures in fluids in thermal nonequilibrium steady states

T. R. Kirkpatrick; J. M. Ortiz de Zárate; J. V. Sengers

doi:10.1103/physreve.89.022145

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arXiv · 1401.1339

Fluctuation-induced pressures in fluids in thermal nonequilibrium steady states

T. R. Kirkpatrick·J. M. Ortiz de Zárate·J. V. Sengers

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Abstract

Correlations in fluids in nonequilibrium steady states are long ranged. Hence, finite-size effects have important consequences in the nonequilibrium thermodynamics of fluids. One consequence is that nonequilibrium temperature fluctuations induce nonequilibrium Casimir-like pressures proportional to the square of the temperature gradient. Hence, fluctuations cause a breakdown of the concept of local thermal equilibrium. Furthermore, transport coefficients become dependent on boundary conditions and on gravity. Thus nonequilibrium fluctuations affect some traditional concepts in nonequilibrium thermodynamics.

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T. R. Kirkpatrick, J. M. Ortiz de Zárate, J. V. Sengers. 2014-02-17. Fluctuation-induced pressures in fluids in thermal nonequilibrium steady states. https://doi.org/10.1103/physreve.89.022145

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