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Published on: July 19, 2016
Variational formulation of nonequilibrium thermodynamics for hydrodynamic pattern formations
1Department of Chemical Engineering, University of Massachusetts, Amherst 01003, USA. hjw2001@med.cornell.edu
Summary
A variational principle for near-equilibrium states, when extended, applies to hydrodynamic flows. This principle shows that entropy production is maximized, guiding system behavior both near and far from equilibrium.
Area of Science:
- Thermodynamics
- Fluid Dynamics
- Statistical Mechanics
Background:
- The Onsager variational principle describes near-equilibrium states.
- Understanding far-from-equilibrium thermodynamics is crucial for complex systems.
Purpose of the Study:
- To extend Onsager's variational principle to hydrodynamic flows.
- To investigate entropy production maximization as a universal principle.
Main Methods:
- Direct extension of the variational principle of near-equilibrium states.
- Analysis of entropy production rate in isolated systems.
Main Results:
- The extended principle applies to hydrodynamic flows.
- Entropy production rate is maximized for extremal paths, both near and far from equilibrium.
- Identified a general pattern selection criterion for far-from-equilibrium systems.
Conclusions:
- Onsager's principle can be generalized to describe hydrodynamic systems.
- Maximum entropy production serves as a unifying principle across different equilibrium regimes.
- The principle offers a predictive framework for pattern selection in complex fluid dynamics.
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