In recent years, building projects have attracted widespread attention due to their excessive carbon emissions and energy consumption, and the pace of building energy efficiency and energy-saving inspection has been stepped up. In energy saving inspection, infrared thermal imaging camera is an important inspection method. The instrument is based on the better temperature analysis and testing method of heat transfer theory, using non-contact detection technology, which will neither affect the object under test nor deface the surface of the object under test.
Infrared thermography technology can be applied in the diagnosis of thermal defects in building envelope structure. Infrared thermograms can show the influence of thermal bridges on the surface temperature of the envelope structure. Combining infrared thermography with inspection examples, the evaluation parameters of indoor thermal defects are proposed. And for indoor thermal defects, the 2 parameters of relative temperature difference and relative area difference on the inner surface of the envelope structure are used for quantitative evaluation and to determine the grade of thermal defects. For example, in the thermal image taken outdoors in winter, the light-colored area is used to show the higher surface temperature of the thermal bridge due to high heat loss, and the dark-colored area is used indoors to show the lower surface temperature of the thermal bridge.
The key to the diagnostic process is to see if there are thermal anomalies on the infrared thermal image, and if there are thermal anomalies. It means that the enclosure has some degree of thermal defects. Thermal defects include lack of insulation, moisture in the insulation and air infiltration conditions. In addition, engineers and technicians have derived multiple types of infrared diagnostic methods based on the principle of infrared diagnosis, including a similar comparison method, file analysis method and thermal spectrogram analysis method.
Infrared thermal imaging cameras have an important role in describing the current state of the building. Compared with other traditional thermal defect detection instruments, infrared thermography has the advantage of truly reflecting the temperature field distribution of the envelope structure. Infrared thermal imaging cameras can visualize the invisible temperature field and show the thermal defects and energy wasting problems of the building, and then target energy-saving renovation, which is a powerful way to reduce energy consumption and carbon emission.
In the actual infrared image acquisition process, thermal imaging technology also found that the infrared thermal imaging camera can give a correct evaluation of many aspects of the thermal performance of the building.
The instrument itself has the advantages of high sensitivity, fast temperature measurement, high detection efficiency, wide detection range, etc. The application in the detection of thermal defects in buildings has a good development prospect.