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Updated: Jul 11, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Weakly and strongly consistent formulations of irreversible processes.
1ETH Zürich, Department of Materials, Polymer Physics, HCI H 543, CH-8093 Zürich, Switzerland. hco@mat.ethz.ch
Physical Review Letters
|October 13, 2007
Summary
We present a new method to check the consistency of thermodynamic models using eigenvalues and eigenmodes. This approach clarifies the role of diffusion terms in hydrodynamic equations.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Fluid Dynamics
Background:
- Assessing the consistency of time-evolution equations in thermodynamics is crucial.
- Models can be evaluated based on building block properties (strong consistency) or evolution equations (weak consistency).
Purpose of the Study:
- To propose a straightforward procedure for checking the strong consistency of thermodynamic models.
- To clarify the role of diffusion terms in hydrodynamic equations.
Main Methods:
- Utilizing eigenvalues and eigenmodes of linearized equations to assess model consistency.
- Relating the method to the establishment of a fluctuation-dissipation theorem.
- Applying the general framework to hydrodynamic models.
Main Results:
- A direct procedure for verifying strong consistency is established.
- The method provides insights into the nature of thermodynamic building blocks.
- The role of diffusion terms in hydrodynamics is clarified.
Conclusions:
- The proposed eigenvalue-based method offers a robust way to check model consistency.
- This approach enhances understanding of thermodynamic model behavior.
- The findings have implications for the formulation of hydrodynamic equations.
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