Department of Physics, School of Science, King Mongkut's Institute of Technology Ladkrabang, Chalongkrung Road, Ladkrabang, Bangkok, 10520, Thailand.
Smart Materials Research and Innovation Unit, School of Science, King Mongkut's Institute of Technology Ladkrabang, Chalongkrung Road, Ladkrabang, Bangkok, 10520, Thailand.
Sci Rep. 2023 Jan 17;13(1):916. doi: 10.1038/s41598-023-28080-7.
To investigate the effect of heat loss reduction due to thermal insulator and thermal interface resistance due to multi-layer structure in order to improve the efficiency of a thermoelectric device, a thermoelectric concrete brick was fabricated using a unileg n-type CaMnO thermoelectric module inside. CaMnO thermoelectric materials were synthesized by starting materials CaCO and MnO to produce a unileg n-type CaMnO module. Thermoelectric concrete brick consisted of two types: I-layer brick (one layer of concrete thermal insulator) and III-layer brick (three layers of different concrete insulators). The occurring temperature difference, electric current and voltage on the CaMnO module and thermoelectric concrete brick were measured in closed and open circuits. The temperature difference, thermal distribution, and output voltage when applying constant temperatures of 100, 200 and 400 °C were measured. Computer simulations of the Finite Element Method (FEM) were performed to compare with the experimental results. The trends of the temperature difference and the output voltage from the experimental and computer simulations were in good agreement. The results of the temperature difference during the hotter side temperature of 200 °C exhibited the temperature difference along the vertical direction of the thermoelectric concrete bricks for both types of the III-layer brick of 172 °C and the I-layer brick of 132 °C are larger than that of the CaMnO TEG module without using a thermal concrete insulator of 108 °C. The thermoelectric concrete bricks of the III-layer brick type of 27.70 mV displayed output voltage results being higher than those of the I-layer brick of 26.57 mV and the CaMnO TEG module without using a thermal concrete insulator of 24.35 mV. Thermoelectric concrete brick of the III-layer brick type displayed higher electric generation power than the I-layer brick and the CaMnO TEG module. Additionally, the results exhibited the capability of thermoelectric concrete brick in the III-layer brick model for electric generation power based on the temperature difference. The TEG concrete brick of I-layer concrete covering the series-parallel combination circuit of 120 modules of the unileg n-type CaMnO was constructed and then embedded on the outer surface of the furnace. During the maximum hotter side temperature of 580 °C of the concrete brick, the temperature difference between the hotter side and the cooler side of the brick occurred at 365 °C and the maximum output voltage was obtained at 581.7 mV.
为了提高热电设备的效率，研究了由于热绝缘材料导致的热损失减少和由于多层结构导致的热界面电阻。为此，我们使用内部的单侧 n 型 CaMnO 热电模块制造了热电混凝土砖。CaMnO 热电材料是通过起始材料 CaCO 和 MnO 合成的，以生产单侧 n 型 CaMnO 模块。热电混凝土砖由两种类型组成：I 层砖（一层混凝土热绝缘体）和 III 层砖（三层不同的混凝土绝缘体）。在封闭和开路条件下测量 CaMnO 模块和热电混凝土砖上的温差、电流和电压。测量了施加 100、200 和 400°C 恒定温度时的温差、热分布和输出电压。使用有限元法（FEM）进行了计算机模拟，以与实验结果进行比较。实验和计算机模拟的温差和输出电压趋势吻合较好。在更热侧温度为 200°C 的情况下，温差结果显示 III 层砖类型的垂直方向上的温差为 172°C，而 I 层砖类型的温差为 132°C，比不使用热混凝土绝缘体的 CaMnO TEG 模块的温差 108°C 大。III 层砖类型的热电混凝土砖的输出电压结果为 27.70mV，高于 I 层砖的 26.57mV 和不使用热混凝土绝缘体的 CaMnO TEG 模块的 24.35mV。III 层砖类型的热电混凝土砖的发电功率高于 I 层砖和 CaMnO TEG 模块。此外，结果表明 III 层砖模型的热电混凝土砖在基于温差的发电功率方面具有能力。建造了一个 I 层混凝土的 TEG 混凝土砖，覆盖单侧 n 型 CaMnO 的 120 个模块的串联-并联组合电路，然后嵌入在炉的外表面。在混凝土砖的最大更热侧温度为 580°C 的情况下，砖的更热侧和更冷侧之间发生的温差为 365°C，最大输出电压为 581.7 mV。
