Journal of the Korean Solar Energy Society (한국태양에너지학회 논문집)

The Korean Solar Energy Society (한국태양에너지학회)
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Nocturnal Radiant Cooling during the Winter by the Plate Viewing the Sky

겨울 야간 하늘에 노출된 평판에 의한 복사냉각 실험

  • 변기홍 (동국대학교 기계공학과)
  • Published : 2008.10.30
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Abstract

The radiant cooling(RC) effects are studied during the winter night. The plate was viewing the nighttime sky. The data were collected at the rooftop of the Engineering building at the Dongguk University in Seoul, Korea. As observed during the summer night, the plate temperature was lower than ambient temperature under the RC favorable conditions. The parameters under study are the wind velocity, cloud index, and visibility for given system size and surface condition. The results follow the same tendency with these parameters as observed from the previous study for the summer night. As long as the wind velocity is less than around 2 m/s, the radiant cooling was observed with the system under study. In some cases, the radiant cooling temperature differences (RCTD) are higher than those for the summer night. The larger the RCTD as the wind velocity decreases and as the sky becomes clear.

Keywords

References

  1. Erell, E. and Etzion, Y., A Radiative Cooling System Using Water as Heat T ransfer Medium, Architect. Sci. Rev., Vol. 35, pp. 35-49, 1992
  2. Meir, M. G., Rekstad, J. B. and Lovvik, O. M., A Study of Polymer‐Based Radiative Cooling System, Solar Energy, Vol. 73, No. 6, pp. 403-417, 2002 https://doi.org/10.1016/S0038-092X(03)00019-7
  3. 변기홍, 야간 하늘에 노출된 평판의 복사냉각 실험, 설비공학 논문집, 제17권, 제6호, pp. 605-610, 2005
  4. 변기홍, 주간 하늘에 노출된 평판에 의한 복사냉각 실험, 한국태양에너지학회 논문집, 제27권, 제 4호, pp. 11-17, 2007
  5. Korea Meteorological Administration, Weather Information Service, Seoul, Korea (www.kma.or.kr), 2004, 2005, 2008
  6. Martin, M. and Berdahl, P., Charac- teristics of Infrared Sky Radiation in the United States, Solar Energy, Vol. 33, No. (3/4), pp. 321-336, 1984 https://doi.org/10.1016/0038-092X(84)90162-2