| Keywords |
Crevice; Shrinkage of insulation board; Surface temperature decrease; Heat & flow simulation; Field measurement; Surface condensation |
| Abstract |
In recent years, due to the strengthening of insulation performance standards and increasing demand for low-energy buildings, the high performance of the insulation material installed in the building is demanded. Meanwhile, crevices due to shrinkage of insulation board may cause thermal bridges and cause a decrease in surface temperature and thermal performance. When the size of the crevices is large, it is difficult to predict only conduction because internal air flow occurs. The purpose of this study is to analyze the heat flow implemented by computational fluid dynamics based on the field measurement and to quantitatively analyze the effect on the crevices by analyzing the effect of the heat flow due to the crevice to lower the surface temperature inside the building wall and the resulting energy loss. After measuring the surface temperature and indoor/outdoor air temperature of the actual wall where condensation occurred in the indoor, the wall was disassembled to check the size of the crevice, and the results of the crevice length and temperature reduction were obtained. Based on this data, the thermal flow analysis is conducted by dividing two cases according to the presence or absence of a crevice connection.
Due to the occurrence of a crevice of 12 to 15 mm, a surface deterioration of about 9 to 10°C occurred in the upper and lower parts of the wall, and the performance standard of the wall was not met. In addition, as a result of the analysis of the wall, the heat transmission coefficient increased by 1.67 times compared to the existing wall due to the occurrence of crevices. |