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Low-dissipation heat devices: unified trade-off optimization and bounds
C de Tomas1, J M M Roco, A Calvo Hernández
1Departamento de Física Aplicada, Universidad de Salamanca, 37008 Salamanca, Spain.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 16, 2013
Summary
This study introduces a unified optimization for cyclic heat devices, balancing energy output and losses. This approach yields performance between maximum efficiency and maximum power, offering energetic advantages for heat engines and refrigerators.
Area of Science:
- Thermodynamics
- Energy Systems Engineering
Background:
- Cyclic heat devices are crucial for energy conversion.
- Optimizing these devices involves balancing efficiency and power output.
- Low-dissipation models are essential for realistic performance analysis.
Purpose of the Study:
- To develop a unified, trade-off-based optimization for low-dissipation cyclic heat devices.
- To analyze performance regimes considering both useful energy and losses.
- To investigate bounds for symmetric and asymmetric devices and highlight advantages over traditional methods.
Main Methods:
- Applying a unified optimization framework.
- Incorporating trade-offs between energy output and dissipation.
- Deriving explicit performance bounds for different device configurations.
Main Results:
- The optimized performance regime is situated between maximum first-law efficiency and maximum power output (χ).
- Explicit performance bounds were determined for both symmetric and highly asymmetric heat devices.
- Similarities between heat engines and refrigerators under this optimization were identified.
Conclusions:
- Trade-off optimization offers energetic advantages for cyclic heat devices.
- The unified approach provides a more comprehensive understanding of device performance.
- This method is applicable to both heat engines and refrigerators, enhancing their design and operation.
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