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

  • Yun, Su-In ;
  • Kim, Kang-Soo
  • 윤수인 ;
  • 김강수
  • Received : 2016.02.04
  • Accepted : 2016.07.04
  • Published : 2016.07.30


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.


Illuminance ratio;CIE standard sky;Split flux method;External obstructions


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