Badillo-Ruiz Carlos Alberto, Olivares-Robles Miguel Angel, Ruiz-Ortega Pablo Eduardo
Instituto Politecnico Nacional, Coyoacan 04430, Mexico.
Entropy (Basel). 2018 Feb 11;20(2):118. doi: 10.3390/e20020118.
In this work, the influences of the Thomson effect and the geometry of the p-type segmented leg on the performance of a segmented thermoelectric microcooler (STEMC) were examined. The effects of geometry and the material configuration of the p-type segmented leg on the cooling power ( Q c ) and coefficient of performance ( C O P ) were investigated. The influence of the cross-sectional area ratio of the two joined segments on the device performance was also evaluated. We analyzed a one-dimensional p-type segmented leg model composed of two different semiconductor materials, B i 2 T e 3 and ( B i 0.5 S b 0.5 ) 2 T e 3 . Considering the three most common p-type leg geometries, we studied both single-material systems (using the same material for both segments) and segmented systems (using different materials for each segment). The C O P , Q c and temperature profile were evaluated for each of the modeled geometric configurations under a fixed temperature gradient of Δ T = 30 K. The performances of the STEMC were evaluated using two models, namely the constant-properties material (CPM) and temperature-dependent properties material (TDPM) models, considering the thermal conductivity ( κ ( T ) ), electrical conductivity ( σ ( T ) ) and Seebeck coefficient ( α ( T ) ). We considered the influence of the Thomson effect on C O P and Q c using the TDPM model. The results revealed the optimal material configurations for use in each segment of the p-type leg. According to the proposed geometric models, the optimal leg geometry and electrical current for maximum performance were determined. After consideration of the Thomson effect, the STEMC system was found to deliver a maximum cooling power that was 5.10 % higher than that of the single-material system. The results showed that the inverse system (where the material with a higher Seebeck coefficient is used for the first segment) delivered a higher performance than the direct system, with improvements in the C O P and Q c of 6.67 % and 29.25 % , respectively. Finally, analysis of the relationship between the areas of the STEMC segments demonstrated that increasing the cross-sectional area in the second segment led to improvements in the C O P and Q c of 16.67 % and 8.03 % , respectively.
在这项工作中，研究了汤姆逊效应和p型分段腿的几何形状对分段式热电微冷却器（STEMC）性能的影响。研究了p型分段腿的几何形状和材料配置对冷却功率（Qc）和性能系数（COP）的影响。还评估了两个连接段的横截面积比对器件性能的影响。我们分析了一个由两种不同半导体材料Bi2Te3和（Bi0.5Sb0.5）2Te3组成的一维p型分段腿模型。考虑到三种最常见的p型腿几何形状，我们研究了单材料系统（两段都使用相同材料）和分段系统（每段使用不同材料）。在固定温度梯度ΔT = 30 K下，对每个建模的几何配置评估了COP、Qc和温度分布。考虑到热导率（κ（T））、电导率（σ（T））和塞贝克系数（α（T）），使用常数特性材料（CPM）和温度相关特性材料（TDPM）两种模型评估了STEMC的性能。我们使用TDPM模型考虑了汤姆逊效应对COP和Qc的影响。结果揭示了p型腿各段中使用的最佳材料配置。根据所提出的几何模型，确定了实现最大性能的最佳腿几何形状和电流。考虑汤姆逊效应后，发现STEMC系统的最大冷却功率比单材料系统高5.10%。结果表明，反向系统（第一段使用塞贝克系数较高的材料）的性能优于正向系统，COP和Qc分别提高了6.67%和29.25%。最后，对STEMC各段面积之间关系的分析表明，增加第二段的横截面积分别使COP和Qc提高了16.67%和8.03%。
