Experimental study of the influences of surface roughness and thermal interface material on the performance of a thermoelectric generator

作者：Qiang Fu, Haitao Wang, Ding Li, Weiyu Liang · 发表于：Physica Scripta · 年份：2023 · DOI：10.1088/1402-4896/ad0eb9 · 被引用次数：2 · 研究领域：Advanced Thermoelectric Materials and Devices、Thermal properties of materials、Thermal Radiation and Cooling Technologies

Abstract Reducing surface roughness and using thermal interface materials (TIMs) at the interfaces between a thermoelectric generator (TEG), heat source, and heat sink are effective strategies for decreasing the thermal contact resistance (TCR) and enhancing the TEG performance. To evaluate the influences of parameters such as the surface roughness, the thermal conductivity of TIM and loading pressure, we conducted experiments to measure the open-circuit voltage and output power of the TEG under various installation conditions. We also analysed the changes in TCR and temperature difference across the TEG module. The experimental findings were validated with numerical simulations using COMSOL Multiphysics under specific conditions. Our results revealed that reducing surface roughness and using TIM could substantially reduce the TCR, increase the temperature difference across the TEG, and increase the output power from the TEG. In our experiments, we used a temperature controller, cartridge heaters and thermocouples to regulate and record the temperatures of the heat source and heat sink. When maintaining a temperature difference of 53 K between the heat source and heat sink, and loading pressure set at 0.2 MPa, without using TIM, as the surface roughness decreased from 2.2 μ m to 0.37 μ m and to 0.03 μ m, leading to a reduction in the TCR from 0.22 K W −1 to 0.17 K W −1 and to 0.13 K/W. Simultaneously, the open-circuit voltage increased from 1.32 V to 1.65 V and to 1.86 V, and...