Transient and non-uniform heat flux effect on solar thermoelectric generator with phase change material
Transient and non-uniform heat flux effect on solar thermoelectric generator with phase change material
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DOI：
10.1016/j.applthermaleng.2020.115206
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发表时间：
2020-06-05
影响因子：
6.4
通讯作者：
Akhlaghi, Yousef Golizadeh
中科院分区：
文献类型：
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作者：
Shittu, Samson;Li, Guiqiang;Akhlaghi, Yousef Golizadeh
来自太阳能聚光器的瞬时和不均匀的热流可能会影响太阳能热电发电机的性能，太阳能热电发电机利用集中的太阳辐射发电。为此，本文详细研究了瞬时热流和非均匀热流对太阳能温差发电器(STEG)性能的影响。采用COMSOL 5.4多物理软件进行数值研究，利用LightTools软件进行光线追踪模拟，得到复合抛物面聚光器的非均匀热流密度。利用了在典型局部多云天气条件下变化的太阳辐射。此外，相变材料(PCM)被用来减小瞬时和不均匀热流的影响，因此它位于太阳能热电发电机的顶面。对有无PCM的STEP性能进行了比较，并对PCM翅片和PCM高度对STEP性能的影响进行了参数研究。结果表明，将相变材料放置在太阳能温差发电器的顶面，是保证太阳能温差发电器在不同天气条件下具有稳定电性能的有效途径。此外，实验结果还揭示了相变材料在太阳高集中辐射下对太阳能温差发电机的有效保护作用。该研究将为不同天气条件下的太阳能热电机组和太阳能集热器的热流不均匀问题提供有价值的设计指导。
Transient and non-uniform heat flux from solar concentrators can affect the performance of solar thermoelectric generators, which generate electricity from concentrated solar radiation. Therefore, this paper presents a detailed three-dimensional study on the effect of transient and non-uniform heat flux on the performance of a solar thermoelectric generator (STEG). COMSOL 5.4 Multiphysics software is utilized for the numerical study while the non-uniform heat flux from a compound parabolic concentrator is obtained through ray tracing simulation using Lighttools software. Varying solar radiation under typical partly cloudy weather condition is utilized. Furthermore, phase change material (PCM) is used to reduce the effect of transient and non-uniform heat flux therefore; it is positioned at the top surface of the solar thermoelectric generator. A comparison between the performance of the STEG with and without PCM is presented, and a parametric study on the effect of PCM fins and PCM height on the STEG performance is carried out. Results show that the place of PCM on the top surface of the solar thermoelectric generator is an effective approach to provide a stable electrical performance form the STEG under varying weather conditions. Furthermore, results reveal the effectiveness of the phase change material in protecting the solar thermoelectric generator under highly concentrated solar radiation. This study will provide valuable design guidance for solar thermoelectric generators under varying weather conditions and with solar concentrators, which produce non-uniform heat flux.