Optimizing low-dissipation Carnot-like thermal devices with heat leak.
1Jiangxi Normal University, College of Physics, Communication and Electronics, Nanchang 330022, China.
Physical Review. E
|October 21, 2025
Summary
This study introduces a unified framework for analyzing heat engines, refrigerators, and heat pumps with heat leak. It reveals optimal performance bounds and power-efficiency trade-offs under realistic conditions.
Area of Science:
- Thermodynamics
- Energy Systems Analysis
- Heat Transfer
Background:
- Optimal performance bounds for heat engines (HEs), refrigerators (REs), and heat pumps (HPs) are crucial thermodynamic challenges.
- Low-dissipation (LD) models offer insights, but the impact of unavoidable heat leak is underexplored in real systems.
Purpose of the Study:
- To develop a unified framework for analyzing LD Carnot-like (CL) HEs, REs, and HPs considering heat leak.
- To derive new results for efficiency at maximum power and power at maximum efficiency.
- To construct Pareto fronts delineating optimal power-efficiency trade-offs under realistic conditions.
Main Methods:
- Developed a unified thermodynamic framework for LD Carnot-like devices with heat leak.
- Derived analytical expressions for efficiency at maximum power and power at maximum efficiency.
- Constructed Pareto fronts by analyzing power-efficiency trade-offs.
Main Results:
- New results for efficiency at maximum power and power at maximum efficiency were derived for LD CL devices with heat leak.
- Pareto fronts were constructed, illustrating optimal power-efficiency trade-offs under realistic conditions.
- Proved that bounds of power at fixed efficiency and efficiency at fixed power coincide, forming these fronts.
Conclusions:
- The study provides a unified framework for understanding the performance limits of heat engines, refrigerators, and heat pumps with heat leak.
- Optimizing the average entropy production rate achieves the derived performance bounds, a principle applicable beyond LD models.
- The findings offer a more realistic assessment of device performance by incorporating heat leak effects.
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