Abstract
The evaluation and renovation of existing building envelope has important practical significance for energy conservation and emission reduction in the field of architecture. With the development of digital cities, 3D models with rich temperature information can realize the comprehensive and accurate detection and evaluation of the existing building envelope. However, the 3D model reconstructed from thermal infrared images has only relative temperature distribution and no temperature value of each location, so it is impossible to quantify the extent of the defect from it. To solve this issue, this paper develops a method to establish a 3D point cloud model with temperature information at selected points. The proposed 3D model is generated based on the thermal infrared images acquired by an unmanned aerial vehicle (UAV) equipped with an infrared camera. In the generated 3D thermal infrared model, we can not only get the relative temperature distribution of the building’s full envelope structure, but also obtain the exact temperature value of any selected point. This method has been verified by field measurements and the result shows that the deviation is within 5 °C. In addition to temperature information, the generated 3D model also has spatial and depth information, which can reflect the appearance information and 3D structure of the monitoring target more realistically. Thus, by using this method, it is possible to achieve a comprehensive, accurate, and efficient on-site assessment of the building envelope in the urban area.
Highlights
Buildings account for about one third of the global primary energy consumption and one third of the total energy-related greenhouse gas emissions [1], and the thermal performance of building envelopes plays an important role in the overall energy consumption of buildings [2]
In order to solve the problem that the temperature of each pixel cannot be read in the 3D model reconstructed from thermal infrared (TIR) images, this paper aims to develop a method of evaluating the thermal performance of building envelope
The main contribution is to obtain the TIR images of the building envelope by the unmanned aerial vehicle (UAV) equipped with an infrared camera, and establish a 3D point cloud model providing temperature information of any selected points
Summary
Buildings account for about one third of the global primary energy consumption and one third of the total energy-related greenhouse gas emissions [1], and the thermal performance of building envelopes plays an important role in the overall energy consumption of buildings [2]. In view of the global warming, energy crisis, and environmental pollution, it is of great practical significance to establish a comprehensive system for monitoring and evaluating the thermal performance of existing building envelopes in urban areas in order to reduce the energy consumption of buildings effectively. High-resolution infrared cameras can provide detailed information about temperature distribution, which can be used to capture thermal anomalies caused by local defects or damage of the buildings and the defect location [3,4,5,6]. With the development of infrared equipment, a handheld thermal infrared (TIR) method has been widely used in the field of architecture [7,8,9]. Energies 2020, 13, 6677 only be used in indoor or outdoor lower levels, the TIR method is only applicable to local detection of building envelopes at present. With the help of the existing detection methods, whether TIR method or thermocouple and hot box method, it is difficult to realize the comprehensive detection of the whole enclosure structure of a single building, especially for buildings with a large volume and high number of floors
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
