- Volume 31 Issue 4
A radiant heating system keeps a space uniformly heated and comfortable. In addition, this system occupies only a small amount of space. Because of these advantages, many countries are now applying this system. However, when applying radiant floor heating, the thermal discomfort that can be caused by the external environment needs to be considered. Recently, the amount of glass area used in office buildings has been increasing. As a result, heat loss through the building envelope has increased, and increasing the risk of the occurrence of downdraft. Downdraft is defined as descending cold air induced by cold windows in colder weather, which may cause thermal discomfort to occupants. Therefore, in this study, the principle of how donwdraft occurs was analyzed. In order to estimate air movement in a room, numerical simulations are performed. A computational model of a room with radiant floor heating is constructed within the CFD program Star CCM+. Eight cases of radiant floor heating with varying surface temperatures, surface areas and window U-value are considered.
바닥 복사난방;열쾌적;다운드래프트;CFD 시뮬레이션
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연구 과제 주관 기관 : 한국연구재단