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Study of Remodified Split Flux Method with Various Sky Conditions and External Obstructions

다양한 천공상태 및 외부 방해물 조건에서 실내주광조도의 평가를 위한 분할광속법의 개선에 관한 연구

  • Received : 2016.02.04
  • Accepted : 2016.07.04
  • Published : 2016.07.30

Abstract

It is important to understand the distribution of luminance of the sky as accurately as possible. The purpose of this study is to modify split flux method, formulae for daylight factor(DF), with variable sky conditions and obstructions. Split flux method has been modified continuously through a number of previous studies. And several studies had also applied this formula not only to the CIE overcast sky but also to the other CIE standard skies. CIE standard skies are studied based on measurement data of real sky. In existing research of split flux, there was no direct sun component in SC(Sky component). So there are 4 cases to modify split flux method with direct sky component, and best case is picked to compare with Desktop radiance program. And also obstructions threw a shadow over 145 sky patchs for the consideration of external obstruction. As a result, the outputs of remodified formulae are improved and outputs of considering external obstruction are enhanced.

Keywords

Acknowledgement

Supported by : 한국연구재단

References

  1. Alshaibani, K. (2011). Finding frequency distributions of CIE Standard General Skies from sky illuminance or irradiance. Lighting Res. Technol. 0. 1-9.
  2. Hopkinson, R. G., Longmore, J., & Petherbridge, P. (1954). An empirical formula for the computation of indirect component of daylight factor. Trans illum Eng Soc. 19(7). 201-219.
  3. Kim, C. S,, & Chung, S. J. (2011). Daylighting simulation as an architectural design process in museums installed with toplights. Building and Environment. 46. 210-222. https://doi.org/10.1016/j.buildenv.2010.07.015
  4. Kittler, R. (1998). A set of standard skies characterizing daylight conditions for computer and energy conscious design, Polygrafia SAV.
  5. Li, D. H. W., Gary, H. W., Cheung, K, L., & Lam, T. N. T. (2010). Determination of vertical daylight illuminance under non-overcast sky conditions. Building and Environment. 45. 498-508. https://doi.org/10.1016/j.buildenv.2009.07.008
  6. Li, D. H. W., Lam, T. N. T., & Wu, T. K. K. (2012). Estimation of average daylight factor under obstructed CIE standard general skies. Lighting res. technol. 0. 1-11.
  7. Li, D. H. W., Chau, T. C., & Wan, K. K. W. (2014). A review of the CIE general sky classification approaches. Renewable and Sustainable Energy Reviews. 31. 563-574. https://doi.org/10.1016/j.rser.2013.12.018
  8. Max R. Nagel. Ground Illumination from a Turbid Cloudless Sky. APPLIED OPTICS. 14(1). 67-75. https://doi.org/10.1364/AO.14.000067
  9. Nexant, Inc. (2008). M&V Guidelines: Measurement and Verification for Federal Energy Projects, Version 3.0, 49-51
  10. Ng, E. (2001). A simplified daylighting design tool for high-density urban residential buildings. Lighting Res. Technol. 33(4). 259-272. https://doi.org/10.1177/136578280103300417
  11. Ng, E., Cheng, V., Gadi, A., Mu, J., Lee, M., & Gadi, A. (2007). Defining standard skies for Hong Kong. Building and Environment. 42. 866-876. https://doi.org/10.1016/j.buildenv.2005.10.005
  12. Tregenza, P. R. (1989). Modification of the split flux formulae for mean daylight factor and internal reflected component with large external obstructions. The Society of Light and Lighting, 21(3). 125-128.
  13. Tregenza, P. R. (1994). Mean Daylight Illuminance in Rooms Facing Sunlit Streets, Building and Environment. 30. 83-89.
  14. Tregenza, P. R. (2004). Analysing sky luminance scans to obtain frequency distributions of CIE Standard General Skies. Lighting Res. Technol. 36(4). 271-281. https://doi.org/10.1191/1477153504li117oa
  15. Yun, K. C., Yun, S. I., Kim, S. S., & Kim, K. S. (2014). Application of simplified daylight prediction method for daylighting performance evaluation on overcast sky, Journal of the Korean Solar Energy Society. Korean Solar Energy Society. 34(5). 1-9. https://doi.org/10.7836/kses.2014.34.5.001
  16. Yun, S. I., Yoon, K., & Kim, K. S. (2014). Application of the daylight factor formula with the modified split flux. Journal of the Korean Solar Energy Society. Korean Solar Energy Society. 34(6). 39-48. https://doi.org/10.7836/kses.2014.34.6.039