Unfortunately, no one can deny the fact that war is a powerful engine of progress. When circumstances demanded quick solutions, and most importantly effective, people created such things that previously could be read only on the pages of science fiction books. And now we cannot imagine our life without many of these things that have come into use. Thermal imager is one of such inventions.
Thermal imagers are used in a variety of industries and purposes. For example, such as: protection of objects, military operations, energy audit to detect refrigerant leakage, diagnostics, astronomy, search and rescue operations, diagnostics of buildings to detect moisture. This is not the whole list of activities in which this device can be useful. Quite often it is also used for domestic purposes.
It would seem that this is real magic. After all, how can the eye see heat? But the holy science of physics has proved that it is quite possible.
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Brief info about thermal vision technology
A thermal imager is a device that helps to see thermal radiation invisible to the human eye from various objects, creatures and people with an accuracy of 0.1 °C and higher in the form of a special thermal map. The palette of the heat map, which is also called a heat map, can be different. And this affects the scope of its use. Sometimes the hottest spots are marked in white, sometimes in red or orange, and the coldest – in black or dark blue.
To understand how a thermal imager works, you need to refer to the laws of physics. Light is a wave of the electromagnetic spectrum. Depending on the energy with which this wave is saturated, it has a different frequency, which corresponds to a different color temperature. For example, red color means the least amount of energy, and blue – the most. When the energy reserves of the wave decrease, its length increases. And so the visible color of light turns from yellow to light red, and then to a more saturated shade. After that, the photon energy is not enough to activate the visual cells on the retina. A person no longer sees light, but this does not mean that it is not there. Just its waves have moved to the infrared spectrum. It is in this spectrum that the thermal imager works.
Thermal scanners in construction
In the modern world, the demand for thermal imagers is noted for all areas of production and quality control. The thermal imager is able to track the slightest thermal change both in a separate part and in the whole mechanism, which allows the use of such a device to create high-quality developments and in design conditions. The use of thermal imagers is also required in the field of construction, for the control of indicators in construction. According to the thermogram data, it is clearly visible which parts are more vulnerable to temperature in order to carry out timely repair or replacement of materials.
As a rule, thermal analysis of the building is carried out both outside and inside the building. Usually the building construction and environmental conditions are taken into account to choose the optimal location of the thermal imager for taking readings. For example, houses equipped with radiators are usually taken from the outside of the building.
Infrared thermography is considered the most effective method by which defects can be identified at an early stage of development. Using an infrared camera, the temperature of the building surfaces is measured. The whole picture of what is happening can be seen very well on the display or on the printout. When analyzing the results, experts give recommendations for eliminating the shortcomings that have been identified. And the most important thing is that you found it at the initial stages.
Thermal scanners in the renovation of buildings
Time is a very capricious phenomenon. And if you have bought a new house, or understand that you have problems in your own building with heat loss, then you should use thermal analysis to reduce energy costs. After all, this is one of the prerequisites for its use to see the changes in heat flow under the influence of changes in external temperatures.
This heat flow, passing through different local zones with different temperatures, shows different temperatures of the surfaces of the building part, and they are recorded by the thermal imager. Modern devices are able to show the difference in temperature up to hundredths of a degree in the heat flux, and therefore identify weaknesses in the building with a difference of 10 degrees in the internal temperature in the room and the environment. While for simpler and older models, a temperature difference of 20 degrees was required to accurately determine the temperature difference in the structural elements.Therefore, the resolution of the thermal imager plays a crucial role in its use throughout the year.
Of course to ensure the best result it is necessary to use both external and internal analysis. Because each of them has both its pros and cons.
The indicators that you get through the external inspection of the building are firstly voluminous, which allows you to have a general picture, but at the same time they are very dependent on many external factors.
In order to get more specific and accurate results, you need to carry out the analysis either early in the morning or late in the evening and in the cool dry season, when the heating system is working. This is necessary in order to observe the necessary difference between the ambient temperature and the building structure itself. In addition, the wind speed is also taken into account. It should not exceed 2 m/s. The position for the most accurate measurement in this case varies and can be adjusted with special tele- or wide-angle optics. However, in this case, the data obtained will be scarce and may contain distortions. It is also necessary to take into account the cold radiation that can be reflected from the roofs and windows of the building. In this case, the thermogram can be noticeably colder than the state of the building in reality. Therefore, after the data obtained, the radiation coefficient is corrected.
After the results obtained for a detailed study of the structural elements it is better to conduct internal thermography. Thermal indicators measured in this way are more consistent with reality because they are less dependent on external factors. One of the most common phenomena that damage the building are cold bridges. These are limited places that, compared to the surrounding surface, have increased heat transfer. They are not only the cause of energy losses, but also lead to wetting of the walls, and as a result to the appearance of fungus. A similar effect can be found in air permeability especially in plaster in the outer walls of lightweight construction. In this case, warm air, which may contain a lot of water vapor, can cool to the temperature of the condensation process. This can cause especially great damage to wooden structural elements.
Due to the fact that such problems can be prevented, avoided or corrected, thermography is a very popular method of detecting air tightness defects in the house. With the help of a thermal imager you immediately have a “color picture” that clearly shows the state of insulation of the building and protects the owner from unnecessary costs for heating and maintenance of the premises.