Radiation Heat-Transfer Coefficient of the Indoor Surface in Ondol Heating Space

온돌난방공간(溫突暖房空間)의 내표면(內表面) 복사열전달률(輻射熱傳達率)에 관(關)한 연구(硏究)

The radiation heat-transfer coefficient is generally used to calculate radiant heat exchange of heating space. The coefficient is evenly adopted in most cases, but it is not correct in actual cases. The purpose of this paper is to grasp the changing aspect of radiation heat-transfer coefficient needed for heating load calculation of radiant heating space. Surface temperatures are measured in an Ondol space, and the coefficients are derived and examined. Gebhart's Absorption Factor Method is used for the calculations of the rates of instantaneous radiant exchange in the room. As the result, it is confirmed that the coefficients are variant according to surface temperatures, and proper coefficients are needed for each of conditions.