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Fluctuation-dissipation theorems for viscoelastic fluids: consistency of extended thermodynamic theories

F. Vazquez·M. A. Olivares-Robles·S. Delgado
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Abstract

Fluctuation-Dissipation Relations (FDR) for a Maxwell fluid are computed via the GENERIC formalism. This formalism is determined by four building blocks, two ``potentials'' (total energy and entropy) and two ``matrices'' which determine the dynamics, but the understanding of fluctuations in a given non-equilibrium system is reduced to determining a single friction matrix. The FDR exhibits interesting features, arising from the type of entropy used in the formalism. We show explicitly this dependence FDR-Entropy, also we show that GENERIC renders results consistent with irreversible linear thermodynamics (TIL) \emph{only} if it is used the corresponding entropy. An inconsistent result is provided by GENERIC when it is used a modified entropy .

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BibTeXRIS

F. Vazquez, M. A. Olivares-Robles, S. Delgado. 2003-06-21. Fluctuation-dissipation theorems for viscoelastic fluids: consistency of extended thermodynamic theories. https://arxiv.org/abs/physics/0306159

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