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Four-Objective Optimizations of a Single Resonance Energy Selective Electron Refrigerator.
Jinhu He1,2,3, Lingen Chen1,2,3, Yanlin Ge1,2,3
1Institute of Thermal Science and Power Engineering, Wuhan Institute of Technology, Wuhan 430205, China.
Entropy (Basel, Switzerland)
|July 8, 2023
Summary
This study optimizes an electron refrigerator using multi-objective optimization, finding that balancing cooling load, performance, and ecological function leads to better design than single-objective approaches. Optimal energy boundary and resonance width values are identified for improved system performance.
Area of Science:
- Thermodynamics
- Refrigeration Technology
- Multi-objective Optimization
Background:
- Established models of single resonance energy selective electron refrigerators (ESER) with heat leakage exist.
- Finite-time thermodynamics provides a framework for analyzing such systems.
Purpose of the Study:
- To perform multi-objective optimization of an ESER using finite-time thermodynamic theory and the NSGA-II algorithm.
- To identify optimal operating parameters for enhanced refrigerator performance.
Main Methods:
- Utilized the NSGA-II algorithm for multi-objective optimization.
- Defined cooling load (R¯), coefficient of performance (ε), ecological function (ECO¯), and figure of merit (χ¯) as objective functions.
- Employed TOPSIS, LINMAP, and Shannon Entropy methods to determine optimal solutions from single and multi-objective optimizations.
Main Results:
- Found that energy boundary (E'/kB) and resonance width (ΔE/kB) significantly influence ESER performance objectives.
- Achieved a deviation index of 0.0812 for four-objective optimization using LINMAP and TOPSIS, outperforming single-objective optimizations.
- Identified optimal ranges for E'/kB (12-13) and ΔE/kB (1.5-2.5) for the four-objective optimization.
Conclusions:
- Multi-objective optimization offers a more comprehensive approach to designing ESERs compared to single-objective methods.
- Appropriate selection of energy boundary and resonance width is crucial for optimizing ESER performance.
- The study provides optimal parameter ranges for designing high-performance ESER systems.
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