Validation of IES-VE for Assessing Daylight Performance of Building Implementing Horizontal Light Pipe and Shading Systems in the Tropics

Abstract

Abstract. Various daylight simulation tools, which are rapidly developed, become a reliable way for simulating the complex daylighting environment. Empirical validation of the daylight simulation tool is essential in determining its reliability, especially in simulating light transport and shading system in the Tropics. Distinct from previous research, the validation involves Horizontal Light Pipe (HLP), a side window with shading systems in different room aspect ratios and orientations. This study aims to validate the simulation results of Integrated Environmental Solutions-Virtual Environment (IES-VE) Radiance IES with the measurement results of physical scaled models for evaluating HLP, light shelves, and blinds' daylight performance under intermediate and overcast sky conditions. Two physical scaled models 1:10 represent office rooms with HLP and shading systems with different room aspect ratios were constructed. Daylight Factor (DF) and Daylight Ratio (DF) of physical scaled model measurement and IES-VE simulation were compared. The results showed that under intermediate and overcast sky conditions, the Pearson correlation between simulation and measurement results using DR and DF was strong, significant, and positive, as high as 0.84 and 0.80, respectively. The Mean Bias Error between simulation and measurement results under intermediate and overcast sky conditions were -12% and -7.7%, respectively. IES-VE is reliable to evaluate the HLP and shading systems' daylight performance with different room orientations in the Tropics.