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http://dx.doi.org/10.7836/kses.2016.36.3.033

A Study on Prediction Method of Sky Luminance Distributions for CIE Overcast Sky and CIE Clear Sky  

Kim, Chul-Ho (Department of Architecture, Graduate School, Korea University)
Kim, Kang-Soo (Department of Architecture, Korea University)
Publication Information
Journal of the Korean Solar Energy Society / v.36, no.3, 2016 , pp. 33-43 More about this Journal
Abstract
Daylight is an important factor which influences building energy efficiency and visual comfort for occupants. It is important to predict precise sky luminance at the early stages of design to reduce light energy in the building. This study predicted sky luminance distributions of standard sky model(CIE overcast sky, CIE clear sky) that was provided from the CIE(Commission internationale de $l^{\prime}{\acute{e}}clairage$). Afterward, result of sky luminance was compared and verified with simulation value of Radiance program. From the CIE overcast sky, zenith and horizon ratio is about 3:1. From the CIE clear sky, luminance value gets most high value around the sun. On the other hand, luminance value is the lowest in the opposite direction of the sun when angle is $90^{\circ}$ between the sun and sky element. As a result of comparing the calculation results with Radiance program, sky luminance prediction error rate is 0.4~1.3% when it is CIE overcast sky. Also, sky luminance prediction error rate is 0.3~1.5% when it is CIE clear sky. When compared with the results of radiance simulation, it was evaluated as fairly accurate.
Keywords
Sky luminance distributions; CIE standard overcast sky; CIE standard clear sky; Prediction method; Radiance;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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1 Yoon, K. C, Yun, S. I, Kim, S. S, Kim, K. S, Application of Simplified Daylight Prediction Method for Daylighting Performance Evaluation on Overcast Sky, The Korean Solar Energy Society, 34(5), pp.1-9, 2014.
2 Yoon, K. C, Kim, K. S, Predicting Daylight Illuminances on Vertical Surfaces Using Luminous Efficacy of Solar Irradiance, The Korean Solar Energy Society, 34(1), pp.19-27, 2014.
3 CIE Standard 011/E:2003, Spatial Distribution of Daylight-CIE Standard General Sky. pp.1-7, 2004.
4 Gregory J. Ward, The RADIANCE Lighting Simulation and Rendering System. Lighting Group Building Technologies Program Lawrence Berkeley Laboratory, pp.1-23, 1994.
5 R. Kittler, S. Darula. The Simultaneous Occurrence and Relationship of Sunlight and Skylight under ISO/CIE Standard Sky Types, Lighting Research and Technology, Vol. 47, pp.565-580, 2014.
6 Danny. H. W. Li. Chris C. S. Lau, Joseph C. Lam. Overcast Sky Conditions and Luminance Distribution in Hong Kong, Building and Environment, 39(1), pp.101-108, 2004.   DOI
7 Norio Igawa, Yasuko Koga, Tomoko Matsuzawa, Hiroshi Nakamura, Models of Sky Radiance Distribution and Sky Luminance Distribution, Solar Energy, 77, pp.137-157, 2004.   DOI
8 Surapong Chirarattananon, Pipat Chaiwiwatworakul, Distributions of Sky Luminance and Radiance of North Bangkok Under Standard Distributions. Renewable Energy, 32(8), pp.1328-1345. 2007.   DOI
9 R. Kittler, S. Darula. The Method of Aperture Meridians: a Simple Calculation Tool for Applying the ISO/CIE Standard General Sky. Lighting Research and Technology, 38(2), pp.109-122, 2006.   DOI
10 Eero Vartiainen. Daylight Modelling with the Simulation Tool DeLight. Helsinki University of Technology Publications in Engineering Physics. 2000.
11 Tsiopoulou Chamaidi, Calibrated Sky Luminance Maps for Daylight Simulation, Technical University Vienna -Continuing Education Center, Austria, 2006.
12 R. Perez, R. Seals, J. Michalsky. All-Weather Model For Sky Luminance Distribution-Preliminary Configuration and Validation, Solar Energy, 50(3), 1993.