Abstract

Influence of area ratio (AR) on main performance parameters of solar chimney power plants (SCPPs) is investigated through a justified 3D axisymmetric CFD model. Geometric characteristics of Manzanares pilot plant (MPP) are taken into consideration for the numerical model. AR is varied from 0.5 to 10 to cover both concave and convex (convergent and divergent) solar chimney designs. Following the accuracy verification of the CFD results and proving mesh-independent solution, main performance oriented parameters are assessed as a function of AR such as velocity, temperature and pressure distribution within MPP, temperature rise of air in collector, mass flow rate of air around the turbine area, dynamic pressure difference across the turbine, minimum static pressure in the entire plant, power output and system efficiency. The results reveal that AR plays a vital role in performance figures of MPP. Mass flow rate of air ($\dot{m}$) is found to be 1122.1 kg/s for the reference geometry (AR = 1), whereas it is 1629.1 kg/s for the optimum AR value of 4. System efficiency (η) is determined to be 0.29% for the reference case; however, it is enhanced to 0.83% for the AR of 4.1. MPP can generate 54.3 kW electrical power in its current design while it is possible to improve this figure to 168.5 kW with the optimal AR value.

中文翻译：

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受发散和会聚烟囱几何形状影响的太阳能烟囱发电厂的性能评估

摘要

通过合理的 3D 轴对称 CFD 模型研究了面积比 (AR) 对太阳能烟囱发电厂 (SCPP) 主要性能参数的影响。数值模型考虑了曼萨纳雷斯中试工厂 (MPP) 的几何特征。AR 从 0.5 到 10 不等，以涵盖凹面和凸面（会聚和发散）太阳能烟囱设计。在对 CFD 结果进行精度验证并证明与网格无关的解决方案之后，主要性能导向参数被评估为 AR 的函数，例如 MPP 内的速度、温度和压力分布、收集器中空气的温升、周围空气的质量流量汽轮机面积、汽轮机的动压差、全厂最小静压、功率输出和系统效率。结果表明，AR 在 MPP 的性能指标中起着至关重要的作用。空气的质量流量 ($\dot{m}$) 对于参考几何形状 (AR = 1) 为 1122.1 kg/s，而对于 4 的最佳 AR 值为 1629.1 kg/s。 系统效率 ( η) 确定为参考案例的 0.29%；然而，对于 4.1 的 AR，它增强到 0.83%。MPP 在其当前设计中可以产生 54.3 kW 的电力，而使用最佳 AR 值可以将该数字提高到 168.5 kW。