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A Study on Downdraft Assessment of the Office Buildings with Radiant Floor Heating System
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 Title & Authors
A Study on Downdraft Assessment of the Office Buildings with Radiant Floor Heating System
Jo, Goo-Sang; Park, So-Jeong; Shin, Dae-Uk; Leigh, Tae-Ha; Yeo, Myoung-Souk; Kim, Kwang-Woo;
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.
Radiant Floor Heating;Thermal comfort;Downdraft;CFD simulation;
 Cited by
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