研究背景
光热发电技术具有大规模储热能力，是一种可平衡可再生能源电力波动性、确保电网稳定运行的太阳能发电技术。塔式光热发电技术可在超过1273K的温度下运行，展现出广阔的发展潜力和应用前景。塔式太阳能集热器一般包括定日镜场和单个大尺寸吸热器或多个小尺寸吸热器。太阳能集热器的光-热性能评估对集热器的设计和优化至关重要。目前，研究太阳能集热器聚光吸热过程中光-热转换特性的方法主要包括实验方法和数值模拟方法。
尽管实验方法可以获得可靠的研究结果，但实验耗时长、昂贵，有时还很危险。此外，实验方法也难以监测吸热器内随时间变化的太阳能流密度分布、温度分布和其他详细的物理场。
数值模拟方法有效地弥补了实验的局限性，它不仅能直观地描述吸热器中的物理场分布，而且能可靠地预测聚光吸热过程的能量转换特性。模拟方法主要包括解析法和计算流体动力学法。解析法具有简单，计算速度快等优点。然而，解析法可能无法考虑不同运行变量之间的复杂关系，导致过度简化，从而影响预测结果的精度。解析法通常适用于结构相对简单的吸热器，如管式吸热器。随着计算机技术的发展，计算流体动力学相关模型的应用日趋广泛。然而，当需要模拟集热器全年光-热特性时，计算流体动力学相关模型的计算量将变得十分巨大，从而导致计算难以进行。
文章概述
主要图文结果
Fig.2 Sketch of the ultra-high-temperature solar tower collector with an elliptical heliostat field and a receiver array.
Fig.3 Computation flowchart of the comprehensive model.
Fig.4 Structure of the ANN model for optical-thermal performance prediction of a single receiver.
Fig.7 Flux distributions on the array aperture during the vernal equinox under the single-point aiming strategy.
Fig.8 Qin,ij of each receiver along the flow loops during the vernal equinox under the single-point aiming strategy.
Fig. 10 Qin,ij of each receiver along the flow loops during the vernal equinox under the single-point aiming strategy.
Fig.11 The real-time optical performance of the heliostat field at three typical dates.
Fig. 12 Real-time optical performance of the heliostat field throughout the year.
Fig. 13 Daily optical performance of the heliostat field throughout the year.
Fig. 14 Monthly optical performance of the heliostat field throughout the year.
Fig. 15 Real-time optical-thermal performance of the collector at three typical dates.
Fig. 16 Real-time optical-thermal performance of the collector throughout the year.
Fig. 17 Daily optical-thermal performance throughout the year.
Fig. 18 Monthly optical-thermal performance and annual performance.
