Performance coefficients of thermoelectric cascade modules and modules with segmented branches
Year: 2025
Type: article
Abstract: The paper presents calculations of the performance coefficient for thermoelectric modules with segmented branches and cascade coolers in a wide range of temperature differences. The objects of calculation are a single-stage thermoelectric module with two-section branches and a two-stage thermoelectric cooler. The calculation of thermoelectric modules is carried out for the maximum performance coefficient mode. In the case of a single-stage module, the operation of one branch is considered. For a two-stage module, the number of branches in the first and second stages is the same. The length of the branches in sections and stages is the same. The calculation does not take into account the temperature losses at heat transfers and the Joule heat released during switching. The temperature dependences of thermoelectric parameters are not taken into account in analytical expressions, and are taken into account numerically (by the method of successive approximations) when calculating modules. The calculation results showed that a two-stage cooler is always energetically more advantageous than a cooler with two-section branches, and the greater the operating temperature difference of the module, the greater the difference in their maximum coefficients of performance. The advantage of a cascade cooler is due to the fact that each stage operates in the maximum coefficient of performance mode, and for a segmented branch it is impossible to ensure the maximum coefficient of performance of each section. The calculation results are confirmed by the results of measurements of the energy parameters of real thermoelectric modules in two operating modes ΔT = 77 and 55 K. Single-stage and two-stage thermoelectric modules are designed so that their coefficients of performance are maximum in these operating modes. For the mode ΔT = 77 K, the coefficient of performance of the two-stage module exceeds the coefficient of performance of the single-stage module by five times. When the temperature difference decreases to 55 K, the two-stage module remains a more energy-efficient solution. These results are important to consider for the competent design of thermoelectric modules.
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4411811882