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Effect of Machine Entropy Production on the Optimal Performance of a Refrigerator
1LEMTA, URA CNRS 7563, University of Lorraine, 2, avenue de la Forêt de Haye, 54518 Vandoeuvre-lès-Nancy, France.
Entropy (Basel, Switzerland)
|December 8, 2020
Summary
This study presents a new model for irreversible Carnot refrigerators, optimizing their design for maximum efficiency. It offers fundamental insights into minimizing energy consumption and improving the coefficient of performance (COP) for cooling systems.
Area of Science:
- Thermodynamics
- Refrigeration Engineering
Background:
- Increasing demand for cooling necessitates optimization of reverse cycle machines.
- Optimization involves design (steady-state) and dynamic (fluctuating load) aspects.
- System load variability requires careful control-command strategies.
Purpose of the Study:
- To propose a novel and comprehensive model for an irreversible Carnot refrigerator.
- To analyze the coupling between heat sources/sinks and the refrigeration machine via heat transfer constraints.
- To establish a reference heat transfer entropy for thermodynamic optimization.
Main Methods:
- Development of a complete thermodynamic model for an irreversible Carnot refrigerator.
- Inclusion of heat transfer constraints coupling the machine with its environment.
- Analysis of entropy production due to internal irreversibilities.
Main Results:
- Identification of a reference heat transfer entropy.
- Determination of optimal allocation of heat transfer conductances.
- Calculation of minimum energy consumption and associated coefficient of performance (COP).
Conclusions:
- The proposed model advances the understanding of irreversible Carnot refrigerators.
- New results provide a fundamental step towards defining the performance upper bound.
- Findings are crucial for optimizing cooling systems under environmental constraints.
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