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Title: Fluctuation theorem and extended thermodynamics of turbulence
Turbulent flows are out-of-equilibrium because the energy supply at large scales and its dissipation by viscosity at small scales create a net transfer of energy among all scales. This energy cascade is modelled by approximating the spectral energy balance with a nonlinear Fokker–Planck equation consistent with accepted phenomenological theories of turbulence. The steady-state contributions of the drift and diffusion in the corresponding Langevin equation, combined with the killing term associated with the dissipation, induce a stochastic energy transfer across wavenumbers. The fluctuation theorem is shown to describe the scale-wise statistics of forward and backward energy transfer and their connection to irreversibility and entropy production. The ensuing turbulence entropy is used to formulate an extended turbulence thermodynamics.  more » « less
Award ID(s):
2028633
PAR ID:
10287493
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
Volume:
476
Issue:
2243
ISSN:
1364-5021
Page Range / eLocation ID:
20200468
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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