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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
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Thermodynamically Constrained Averaging Theory: Principles, Model Hierarchies, and Deviation Kinetic Energy
Cass T Miller1, William G Gray1, Christopher E Kees2
1Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC 27599-7431, USA.
Entropy (Basel, Switzerland)
|December 3, 2020
Summary
The thermodynamically constrained averaging theory (TCAT) provides consistent, thermodynamically sound models for multiphase, multiscale systems. This work enhances TCAT accessibility and extends it for complex flows like turbulent multiphase systems.
Area of Science:
- Multiphase flow modeling
- Thermodynamics
- Continuum mechanics
Background:
- Hierarchical models are crucial for multiphase, multiscale systems.
- The thermodynamically constrained averaging theory (TCAT) offers a robust framework for developing these models.
- Existing TCAT applications can be complex to formulate.
Purpose of the Study:
- To make the thermodynamically constrained averaging theory (TCAT) more accessible for practical applications.
- To extend TCAT to include deviation kinetic energy for broader applicability.
- To enable higher-fidelity models for complex systems like turbulent multiphase flows.
Main Methods:
- Formulating hierarchies of models based on the second law of thermodynamics.
- Utilizing existing TCAT components to reduce formulation effort.
- Extending TCAT by incorporating deviation kinetic energy and associated equations.
Main Results:
- TCAT ensures thermodynamic consistency across disparate length scales.
- A structured approach to model building is inherent in TCAT.
- The inclusion of deviation kinetic energy expands TCAT's applicability to flows beyond slow porous media.
Conclusions:
- TCAT provides a powerful, consistent framework for multiphase, multiscale modeling.
- Simplifying TCAT application accelerates the development of advanced models.
- The extended TCAT is suitable for high-fidelity simulations of complex fluid dynamics.
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