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Optimal low symmetric dissipation Carnot engines and refrigerators
C de Tomás1, A Calvo Hernández, J M M Roco
1Departamento de Física Aplicada, Universidad de Salamanca, E-37008 Salamanca, Spain.
Summary
A new optimization criterion unifies Carnot engines and refrigerators by maximizing heat absorbed multiplied by efficiency over time. This approach recovers existing efficiencies for engines and provides a new one for refrigerators.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Physical Chemistry
Background:
- Carnot engines and refrigerators are fundamental thermodynamic devices.
- Optimizing their performance under realistic, non-ideal conditions (dissipation) is crucial.
- Existing criteria for maximum power or efficiency may not apply universally.
Purpose of the Study:
- To propose a unified optimization criterion for both Carnot engines and refrigerators.
- To apply this criterion to low-dissipation Carnot devices.
- To recover known efficiencies and derive new ones.
Main Methods:
- Developing a unified optimization criterion based on maximizing the product of heat absorbed and efficiency per unit time.
- Applying the criterion to endoreversible Carnot engines and refrigerators.
- Comparing results with established theoretical frameworks.
Main Results:
- The proposed criterion, when applied to engines, aligns with the maximum power criterion, yielding the Curzon-Ahlborn efficiency.
- For refrigerators, the criterion yields a new efficiency formula, the counterpart to the Curzon-Ahlborn efficiency.
- This unified criterion is applicable to systems with symmetric dissipation.
Conclusions:
- A single optimization principle can govern the performance of both heat engines and refrigerators.
- The unified criterion provides a powerful tool for analyzing and designing thermodynamic devices.
- This work offers a new perspective on optimizing energy conversion and utilization.
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