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An Overview on Irreversible Port-Hamiltonian Systems.
Hector Ramirez1, Yann Le Gorrec2
1Departamento de Electrónica, Universidad Técnica Federico Santa María, 2390123 Valparaiso, Chile.
This study presents a unified irreversible port-Hamiltonian system formulation for thermodynamic systems. It extends classical port-Hamiltonian systems to include irreversible mechanical and thermal coupling, ensuring energy conservation and encoding the second law.
Area of Science:
- Thermodynamics
- Mathematical Physics
- Systems Theory
Background:
- Classical port-Hamiltonian systems model energy-preserving systems.
- Irreversible thermodynamic processes require extensions to existing formalisms.
- Coupling mechanical and thermal phenomena presents modeling challenges.
Purpose of the Study:
- To provide a unified formulation for irreversible port-Hamiltonian systems.
- To extend port-Hamiltonian systems to handle irreversible thermodynamic processes.
- To develop a framework for modeling coupled thermo-mechanical systems.
Main Methods:
- Developed an irreversible port-Hamiltonian system formulation.
- Incorporated an energy-preserving and entropy-increasing operator for thermal coupling.
- Utilized co-state variables to define a nonlinear operator dependent on the total energy gradient.
- Demonstrated the formalism on finite and infinite dimensional systems.
Main Results:
- The proposed formulation explicitly couples irreversible mechanical and thermal phenomena.
- The formalism guarantees energy conservation through a skew-symmetric operator.
- The second law of thermodynamics is encoded as a structural property of the system.
- Reversible and conservative systems are shown as a special case.
Conclusions:
- The irreversible port-Hamiltonian system formulation offers a unified approach for diverse thermodynamic systems.
- This framework effectively models coupled thermo-mechanical phenomena and incorporates irreversibility.
- The approach provides a robust mathematical structure for analyzing energy and entropy dynamics.
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