ABSTRACT

The Concentration Ratio (CR) is one of the first parameters defined before starting a Parabolic Trough Collector (PTC) construction project as it can easily provide access to the operating temperature and the determination of geometric dimensions. Few studies have been conducted to highlight the importance of the CR. Hence, this work aims to numerically analyze three models of PTC, A, B, and C, with different concentration ratios to perform a comparative analysis of impacts of this parameter in the size and optical efficiency of the models. We used the Monte Carlo Ray Tracing (MCRT) method through the SolTrace software to perform this study. From the results, we conclude that the CR has a considerable effect on the size and optical efficiency of the PTC. On average, the results presented showed that for every $1\mathrm{\%}$ gain in PTC optical efficiency, it would be necessary to increase the concentration rate by $2.69\mathrm{\%}$. However, it is noticed that these gains are not linear and decrease as the concentration rate increases. Also, the increase in the CR leads to an increase in the rim angle, in the collector aperture width, and in the solar energy flux density around the absorber. Finally, the results we found were investigated and validated, presenting excellent agreement with other works in the literature.

摘要

浓度比 (CR) 是开始抛物槽收集器 (PTC) 建设项目之前定义的第一个参数之一，因为它可以轻松提供对工作温度的访问和几何尺寸的确定。很少有研究强调 CR 的重要性。因此，本工作旨在对具有不同浓度比的 PTC、A、B 和 C 三种模型进行数值分析，以比较分析该参数对模型尺寸和光学效率的影响。我们通过 SolTrace 软件使用蒙特卡罗光线追踪 (MCRT) 方法来执行这项研究。从结果中，我们得出结论，CR 对 PTC 的尺寸和光学效率有相当大的影响。平均而言，所呈现的结果表明，对于每个$1\mathrm{\%}$ PTC 光学效率的提高，有必要将浓缩率提高 $2.69\mathrm{\%}$. 然而，注意到这些增益不是线性的并且随着浓缩率的增加而减少。此外，CR 的增加导致边缘角、收集器孔径宽度和吸收器周围太阳能通量密度的增加。最后，对我们发现的结果进行了调查和验证，与文献中的其他作品非常吻合。