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Power, efficiency, and fluctuations in steady-state heat engines
Giuliano Benenti1,2,3, Giulio Casati1,4, Jiao Wang5
1Center for Nonlinear and Complex Systems, Dipartimento di Scienza e Alta Tecnologia, Università degli Studi dell'Insubria, via Valleggio 11, 22100 Como, Italy.
Physical Review. E
|November 20, 2020
Summary
Interacting systems are essential for optimal steady-state heat engine performance. Nonlinear scattering theory bounds the quality factor (Q) at 3/8 near Carnot efficiency, while interactions enable reaching the universal upper bound of Q=1/2.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Dynamical Systems Theory
Background:
- The quality factor (Q) in heat engines measures the balance between power, efficiency, and fluctuations.
- Understanding performance limits is crucial for designing efficient energy conversion devices.
Purpose of the Study:
- To investigate the theoretical bounds of the quality factor (Q) in steady-state heat engines.
- To determine the role of system interactions and integrability in achieving optimal engine performance.
Main Methods:
- Analysis of nonlinear scattering theory in classical and quantum mechanics.
- Examination of interacting, nonintegrable, and momentum-conserving systems.
Main Results:
- Nonlinear scattering theory imposes a bound of Q=3/8 near Carnot efficiency.
- Interacting, nonintegrable, and momentum-conserving systems can achieve Q=1/2, the linear response upper bound.
Conclusions:
- System interactions are necessary to attain the optimal performance bound (Q=1/2) in steady-state heat engines.
- The findings highlight the importance of non-integrability and interactions for efficient thermodynamics.
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