Ключевые слова: thermogram

Field thermal imaging surveys of residential buildings – a prerequisite for the development of energy-efficient external enclosures

https://doi.org/10.58224/2618-7183-2024-7-6-1
Аннотация
The work involved a full-scale thermal imaging survey of a residential building during a hot period of time, where the effect of solar heating of the building's façade and the inner surface of the outer enclosure was studied, taking into account the orientation of the building and the time of the survey. As a result, it was found that the effect of solar heating on the building’s façade significantly increases the temperature on the façade surface, where, depending on the façade orientation and time, the building’s façade surface is exposed to heating from the east, west and south sides. Thus, the maximum values of the façade surface temperature reach 63.1°C, 57.0°C and 53.4°C, respectively, which is almost twice as high as the initial temperature values. Solar heating also has a significant effect on the temperature of the inner surface of the external enclosure, also depending on the façade orientation. Thus, on the east side in the morning, the surface temperature of the external enclosure increases by 3.8°C, which continues until 16:00. The influence of the sun provokes heating of the inner surface of the external enclosure of the living room on the western side by 4.2°C, and on the southern side the maximum temperature on the surface of the inner enclosure was observed in the period from 12:00 to 16:00, which exceeded the initial one by up to 3.8°C. At that, the influence of heating from the sun on the northern side was not observed. With that, it was found that the influence of solar heating of the building façade provokes deviations in the microclimate of the room, where the deviation in the permissible internal air temperature of the living room is 14.1% during the day, and in the optimal humidity by 13.3% in the afternoon. The findings of this study can be taken into account when designing or developing new energy-efficient external enclosing wall structures, where the criterion of heat resistance must also be taken into account in parallel with the criterion of heat protection in the climatic features of the Republic of Kazakhstan.
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Thermovision study of a residential building under climatic conditions of South Kazakhstan in a cold period

https://doi.org/10.58224/2618-7183-2024-7-2-1
Аннотация
In this study, a nine-storey residential building was examined for thermal protection, located in Shymkent, Republic of Kazakhstan. Two two-room flats were considered with the possibility to inspect the exterior envelopes in four orientations. The examination was carried out at different times of the day according to three criteria: exterior envelope in the form of corner joints, translucent enve-lope in the form of window openings and the exterior façade of the building. The study found that the temperature at the surface of the room joints at lunchtime increased from 0.8% to 12% depending on the orientation of the exterior envelope. At the same time, it was found that in the morning and evening hours the temperature inside the living rooms is maintained at 25.8 - 26.5ºC due to excessive con-sumption of heat energy by increasing the heating power up to 15.6% relative to lunchtime, which leads to an excessive increase in air temperature by 7 - 18%. The value of humidity of living rooms also showed non-compliance with the optimal value by 3 - 15% relative to the current norms. As a result of the analysis of thermograms of translucent openings it was found that the surface temperature of the envelope at lunchtime increased by 9.9 - 23.2% in all cases of orientations, and the surface tem-perature of translucent openings of southern orientation is on average 18.2% higher relative to other orientations, which also indicates the influence of solar radiation on the thermal values of translucent openings. The analysis of thermograms and temperature of characteristic points of the external façade with regard to orientations showed a temperature difference from 7.5ºC to 21ºC depending on the ori-entation of the building, where the most exposed to solar radiation façade of southern orientation, which showed an increase in surface temperature by 3 times. Thus, the obtained results of the study will further contribute to the development of energy-efficient designs of external enclosures, consider-ing the influence of all factors on the process of heat exchange, which is the main objective of the au-thors’ comprehensive study.
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