Geometry optimization of a thermoelectric generator with temperature-dependent properties

• Published in: Applied physics. A, Materials science & processing Materials science & processing, 2024-06, Vol.130 (6), Article 447
• Main Authors: Amiri, L., Liang, C.-T., Narjis, A., Alsaad, A.
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Condensed Matter Physics; Design optimization; Machines; Manufacturing; Nanotechnology; Optical and Electronic Materials; Physics; Physics and Astronomy; Processes; Rapid Communications; Surfaces and Interfaces; Temperature dependence; Thermoelectric generators; Thermoelectricity; Thin Films
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-024-07614-4

Maximizing the power delivered by a thermoelectric generator (TEG) (with an internal resistance R TE ) can be achieved by optimizing its design taking into account the external load (with a resistance of R L ). In the present work, the evolution of the thermoelectric (TE) properties of the materials along the leg was considered. By considering a fixed heat rate on the hot side, the powers delivered by various TEGs were assessed by varying the length of the legs. After that, analytical approach was detailed based on the mathematical formulas governing the thermal and electrical transports. This approach revealed that the ratio m  =  R L /R TE is between the most commonly claimed values (1 and (1 +  zT ) 1/2 ). Our variable properties model reveals that the optimal design requires lower cost than that considered by equaling R TE and R L ( m  = 1). This finding turns out to be more and more valid for materials which present a linear variation of temperature with position.