| Abstract |
Low-to-medium temperature geothermal resources exhibit huge global reserves and development potential, yet current utilization remains predominantly limited to direct-use applications. Thermoelectric power generation(TEG) technology based on the Seebeck effect offers a novel approach for comprehensive utilization of low-grade geothermal resources. However, the integrated system design and efficiency enhancement of hydrothermal-type geothermal TEG systems remain critical challenges. This study employed a self-developed TEG system testing platform to conduct comparative performance evaluations and optimization of key components in flat-plate geothermal TEG systems. The impacts of microchannel heat sink structures, thermal interface materials, and assembly pressures on heat transfer characteristics and thermoelectric conversion efficiency were systematically investigated, and the optimized strategies for geothermal TEG system performance enhancement were proposed. Experimental results revealed that compared to conventional straight microchannel heat sinks, interrupted microchannel configurations were observed to enhance TEG unit conversion efficiency by over 40.0%. Through optimized selection of thermal interface materials considering both thermal conductivity and interfacial filling properties, the conversion efficiency can be enhanced by up to 229%. Appropriately increasing assembly pressure further elevates system efficiency within 2.5%-16.3%. The proposed multidimensional collaborative optimization framework for flat-plate TEG systems helps to provide significant technical guidance and practical insights for the design of low-grade geothermal power generation systems. |