Curtain walls are more and more commonly used as building facades. They allow a better daylight availability and a direct connection to exterior environments. Meanwhile, due to the high specular reflections, they may also introduce negative impacts, such as glare and urban heat island effects, to the surround, especially in dense and urban environments. Therefore, it is important to effectively characterize the reflected sunlight from curtain walls. This study aimed to compare how different simulation methods can be used to characterize the reflected sunlight from curtain walls. It was found that the modeling of the sun and sky, ambient calculation, and the modeling of the building façade significantly affected the simulation results. A combination of forward and backward ray-tracing is recommended, with forward ray-tracing for identifying the curtain wall areas reflecting sunlight and backward ray-tracing for calculating illuminance due to reflected sunlight. A follow-up work is planned to investigate how different parameters will affect the simulation results and which method can produce similar results as field measurements.

幕墙越来越多地用作建筑立面。它们提供了更好的日光可用性，并可以直接连接到外部环境。同时，由于高镜面反射，它们还可能对周围环境产生负面影响，例如眩光和城市热岛效应，尤其是在密集和城市环境中。因此，重要的是有效地表征从幕墙反射的阳光。这项研究旨在比较如何使用不同的模拟方法来表征幕墙反射的阳光。结果发现，太阳和天空的建模，环境计算以及建筑立面的建模对模拟结果有很大影响。建议同时使用向前和向后光线跟踪，前向光线跟踪用于识别反射阳光的幕墙区域，后向光线跟踪用于计算反射的阳光导致的照度。计划进行后续工作，以研究不同参数如何影响模拟结果以及哪种方法可以产生与现场测量结果相似的结果。