Dalkiranis Gustavo G, Bocchi João H C, Oliveira Osvaldo N, Faria Gregório C
São Carlos Institute of Physics, University of São Paulo, P.O. Box 369, 13560-970 São Carlos, SP, Brazil.
Catalan Institute of Nanoscience and Nanotechnology (ICN2), Edifici ICN2, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
ACS Omega. 2023 Mar 1;8(10):9364-9370. doi: 10.1021/acsomega.2c07916. eCollection 2023 Mar 14.
Thermoelectric materials capable of converting heat into electrical energy are used in sustainable electric generators, whose efficiency has been normally increased with incorporation of new materials with high figure of merit (ZT) values. Because the performance of these thermoelectric generators (TEGs) also depends on device geometry, in this study we employ the finite element method to determine optimized geometries for highly efficient miniaturized TEGs. We investigated devices with similar fill factors but with different thermoelectric leg geometries (filled and hollow). Our results show that devices with legs of hollow geometry are more efficient than those with filled geometry for the same length and cross-sectional area of thermoelectric legs. This behavior was observed for thermoelectric leg lengths smaller than 0.1 mm, where the leg shape causes a significant difference in temperature distribution along the device. It was found that for reaching highly efficient miniaturized TEGs, one has to consider the leg geometry in addition to the thermal conductivity.
能够将热能转化为电能的热电材料被用于可持续发电机中，通过加入具有高优值（ZT）值的新材料，其效率通常会提高。由于这些热电发电机（TEG）的性能还取决于器件几何形状，在本研究中，我们采用有限元方法来确定高效小型化TEG的优化几何形状。我们研究了具有相似填充因子但热电腿几何形状不同（实心和空心）的器件。我们的结果表明，对于相同长度和横截面积的热电腿，空心几何形状腿的器件比实心几何形状腿的器件效率更高。在热电腿长度小于0.1毫米时观察到这种行为，此时腿的形状会导致沿器件的温度分布有显著差异。研究发现，为了实现高效小型化TEG，除了热导率外，还必须考虑腿的几何形状。
