Energetic Self-Optimization Induced by Stability in Low-Dissipation Heat Engines
J Gonzalez-Ayala1,2, J Guo1,3, A Medina1,2
1Departamento de Física Aplicada.
Physical Review Letters
|February 22, 2020
Summary
Local stability in weakly dissipative heat engines drives self-optimization of thermodynamic quantities like efficiency and power. Irreversible behavior acts as an attractor, guiding system energetics toward improved performance.
Area of Science:
- Thermodynamics
- Non-equilibrium systems
- Statistical mechanics
Background:
- Analysis of cyclic energy converters often focuses on performance metrics.
- The interplay between stability and self-optimization in thermodynamic systems is underexplored.
- Weakly dissipative heat engines represent a key area for studying complex energy conversion processes.
Purpose of the Study:
- To analyze the local stability of weakly dissipative heat engines.
- To connect stability to a multi-objective optimization perspective for thermodynamic quantities.
- To investigate if stability promotes self-optimization of efficiency, power, and entropy generation.
Main Methods:
- Analysis of system dynamics simulating restitution forces and harmonic potentials.
- Examination of relaxation trajectories towards a steady state.
- Statistical analysis of random perturbations and fluctuations.
Main Results:
- Relaxation trajectories are not arbitrary but improve multiple energetic functions.
- Irreversible behavior acts as an attractor for system energetics.
- The endoreversible limit serves as an upper bound, and the Pareto front as a global attractor.
- Fast relaxation is linked to self-optimization, while slow relaxation indicates better performance.
Conclusions:
- Stability in weakly dissipative heat engines inherently favors self-optimization of thermodynamic performance.
- Irreversible processes and Pareto fronts play crucial roles in guiding system energetics.
- Understanding stability-performance trade-offs offers new avenues for controlling and enhancing real-world engine operation.
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