Jeong-Gook Kim

Appropriate conditions for determining the temperature difference ratio via infrared camera

The temperature difference ratio is used to measure the thermal performance of a building envelope. Calculation of temperature difference ratio requires temperature differences between indoor and outdoor environments and wall surface temperatures, obtained here using an infrared camera. This approach performs well when the temperature differential between indoor and outdoor environments is greater than 10℃ and when wind speed is less than 3.0 m/s. We identify periods suitable for accurate evaluation of thermal insulation performance with an infrared camera, based on eight cities in Korea. The number of measureable hours ranges between 3183 and 1317 annually. Optimum periods for measurement are between November and March, specifically between 01:00 and 09:00 h. Measurements obtained during these periods can therefore be regarded as relatively accurate. Practical application: A thermal imaging camera provides an easy method for checking the insulation performance and construction conditions of a building. Conventionally, this would be checked experimentally, but thermal imaging allows easy visualization of conditions.

An Analysis of the Airtightness Performance and Heating Energy Demand According to Building Structural Characteristics -Focused on Newly Apartment Houses-

Purpose: The importance of building airtightness is increased as the demand and expectation of building energy efficiency is growing. Previous research only focused on airtightness of building openings only to improve building airtightness. However, the analysis of difference of airtightness performance according to the characteristic of building structure has not been performed. Therefore, this study analyzed the difference of airtightness performance according to building structural characteristics in a number of ways. Method: Airtightness that are classified as rigid-frame type or wall type are measured and analyzed the difference of airtightness performance between rigid frame type apartments and wall type apartments. This study calculated the heating energy demand and quantitatively analysis using ISO 13790. Futhermore, this study compared research trend of domestic airtightness performance with airtightness standards of the developed countries based on the field measurement. Result: Airtight performance of wall type is better than rigid frame type in terms of energy saving. The difference of heating energy demand between wall type and rigid frame type was .