在已知光源光强分布和室内空间结构的条件下,对空间表面双向反射分布函数(BRDF)进行了假设,并建立数学模型,通过实验对相关参数进行了调整。模拟了不同类型空间模型中的光照情况,并将工作面相关参数值与DIALux仿真结果进行了比较,平均照度误差值小于±3%,平面照度曲线分布基本相同。针对反射部分光能分布不均匀的问题,对墙面BRDF模型进行了改进,得到了较好的仿真效果。所提方法很好地解决了圆形底面空间、底部不等高空间下照度不能直接进行计算的问题。

Based on the known light intensity distribution of a light source and indoor spatial structure, this study established a mathematical model and adjusted the relevant parameters through experiments with respect to a hypothesis about the bidirectional reflectance distribution function (BRDF) of the spatial surface. Further, the application of this mathematical model in different types of spatial models results in an average illuminance error of less than 3%. Moreover, the plane illumination curve distribution is basically similar to those obtained using the existing methods. The working-surface related parameter values are compared with the DIALux simulation results. This study also improves the BRDF model of a wall surface in terms of the application of the uneven light energy distribution on the reflective part. The proposed method improves the illuminance calculation accuracy in a circular bottom space or a space with its bottom not equal to height where a direct calculation is not available.