A new simple method to measure wall thermal transmittance in situ and its adaptability analysis

Meng, Xi; Luo, Tao; Gao, Yawen; Zhang, Lili; Shen, Qiong; Long, Enshen

doi:10.1016/j.applthermaleng.2017.05.074

Cited by 61 publications

(40 citation statements)

References 21 publications

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“…Drawbacks -Non-invasive method [18]; -The higher the temperature gradient, the more reliable the results are [18]; -Internationally recognized and most widely used [19]; -Lightweight and easy to carry equipment [20]; -Can be used in controlled laboratory conditions or in in-situ measurements [17].…”

Section: Advantagesmentioning

confidence: 99%

“…Other works have reported that the accuracy, error and uncertainty of the results achieved using the HFM method can be affected by practical issues (for example the measurement locations), and by temperature fluctuations and small temperature difference between the interior and exterior environments [20][112] [120][121] [122]; so the tests must be performed during the heating period (winter), to ensure the largest temperature difference. To overcome outdoor and indoor thermal environment limitation of the HFM method and to avoid the heavy equipment of the HB, Meng et al [19] proposed a new simple HB -HFM method for in-situ measurements ( Figure 7).…”

Section: In-situ Measurementsmentioning

confidence: 99%

“…Sketch of the simple HB -HFM method proposed by Meng et al[19] for the in-situ measurement of walls thermal transmittance. Figure adapted from ref [19]…”

mentioning

confidence: 99%

See 2 more Smart Citations

Laboratory and in-situ non-destructive methods to evaluate the thermal transmittance and behavior of walls, windows, and construction elements with innovative materials: A review

Soares

Martins

Gonçalves

et al. 2019

Energy and Buildings

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The experimental characterization of the overall thermal transmittance of homogeneous, moderately-and non-homogeneous walls, windows, and construction elements with innovative materials is very important to predict their thermal performance. It is also important to evaluate if the standard calculation methods to estimate the U-value of new and existing walls can be applied to more complex configurations, since the correct estimation of this value is a critical requirement when performing building energy simulations or energy audit. This paper provides a survey on the main methods to measure the thermal transmittance and thermal behaviour of construction elements, considering laboratory conditions and in-situ non-destructive measurements. Five methods are described: the heat flow meter (HFM); the guarded hot plate (GHP); the hot box (HB), considering the guarded HB (GHB) and the calibrated HB (CHB); and the infrared thermography (IRT). Then, previous studies dedicated to the assessment of the thermal performance of different heavy-and light-weight walls are discussed. Particular attention is devoted to the measurement of the U-value of nonhomogeneous walls, including the effect of thermal bridging caused by steel framing or mortar joints, and the presence of PCMs or new insulation materials in the configuration of the walls. hot box; calibrated hot box; infrared thermography. Highlights: -Review on the main methods to measure the U-value of non-homogeneous walls. -Methods: heat flow meter, guarded hot plate, guarded and calibrated hot box, infrared thermography. -Standards framework and discussion of the main advantages and drawbacks of each method. -Description of methodologies and working principles of laboratory and in-situ measurements. -Measurement of the thermal transmittance of different heavy-and light-weight walls.

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Section: Advantagesmentioning

confidence: 99%

Section: In-situ Measurementsmentioning

confidence: 99%

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Laboratory and in-situ non-destructive methods to evaluate the thermal transmittance and behavior of walls, windows, and construction elements with innovative materials: A review

Soares

Martins

Gonçalves

et al. 2019

Energy and Buildings

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“…In 2015, in their turn, authors had verified the feasibility of a new developed simple hot box-HFM method (SHB-HFM) to address an in situ measurement of wall thermal transmittance [68]. This SHB-HFM was preceded by another experiment developed by Chinese researchers in 2012, designated Temperature Control Box-HFM method (TCB-HFM) [69] cited in [70]. However, the authors of [70] (p. 748) described this TCB-HFM as not suitable for the in situ measurement, also noticing that measurement thermal transmittance results obtained in [69] were "55% higher than the design thermal transmittance and that the measurement error was attributed to high moisture", denoting the problem of not controlling for humidity in the test.…”

Section: State Of the Artmentioning

confidence: 99%

“…Besides the final aim of monitoring hygrothermal parameters instead of exclusively the thermal transmittance, the most significant difference between the boxes presented in [68] or [70] In situ monitoring can be very significant in the case of historic buildings, since: (i) walls samples cannot be examined in the lab (for cultural heritage protection issues, no samples can be removed from original sites); (ii) many historic buildings are abandoned or not in use, and, therefore, are not heated; (iii) many of these building present particular features as high ceilings/volumes and therefore the traditional 1 m × 1 m lab measured surface might not be representative enough of the vertical heat stratification of a historic wall.…”

Section: State Of the Artmentioning

confidence: 99%

Design and Construction of a New Metering Hot Box for the In Situ Hygrothermal Measurement in Dynamic Conditions of Historic Masonries

et al. 2020

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The main purpose of the HeLLo project is to contribute to data available on the literature on the real hygrothermal behavior of historic walls and the suitability of insulation technologies. Furthermore, it also aims at minimizing the energy simulation errors at the design phase and at improving their conservation features. In this framework, one of the preliminary activities of the study is the creation of a real in situ hot box to measure and analyze different insulation technologies applied to a real historic wall, to quantify the hygrothermal performance of a masonry building. Inside this box, ‘traditional’ experiments can be carried out: recording heat flux, surface temperature, and air temperatures, as well as relative humidity values through the use of a new sensing system (composed of thermocouples and temperature/relative humidity combined sensors). Within this paper, the process of development, construction, and validation of this new metering box is exhibited. The new hot box, specifically studied for historic case studies, when compared to other boxes, presents other advantages compared to previous examples, widely exemplified.

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Application of Object Detection Algorithm for Efficient Damages Identification of the Conservation of Heritage Buildings

Tang,

Feng,

Wang

et al. 2024

Archaeological Prospection

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Heritage buildings are crucial for any area's cultural and political aspects. Proper maintenance and monitoring are essential for the conservation of these buildings. However, manual inspections are time‐consuming and expensive. We propose a deep learning–based detection framework to identify the damages on the ancient architectural wall. The algorithm applied in this study is YOLOv5. Comparing its five different versions, it was decided to use YOLOv5m as the most accurate detection algorithm with a mAP of 0.801. The damage types identified are physical weathering and visitors' scratches. High‐resolution images were selected for the experiment and effectively identified image. In addition, the applied algorithm allows real‐time detection and the identification of seasonal sources of disruption, which is proved by the video test in this study. The findings contribute to the development of an intelligent tool for health monitoring with the goal of fast and remote damage detection in the routine maintenance of heritage buildings.

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A new simple method to measure wall thermal transmittance in situ and its adaptability analysis

Cited by 61 publications

References 21 publications

Laboratory and in-situ non-destructive methods to evaluate the thermal transmittance and behavior of walls, windows, and construction elements with innovative materials: A review

Laboratory and in-situ non-destructive methods to evaluate the thermal transmittance and behavior of walls, windows, and construction elements with innovative materials: A review

Design and Construction of a New Metering Hot Box for the In Situ Hygrothermal Measurement in Dynamic Conditions of Historic Masonries

Application of Object Detection Algorithm for Efficient Damages Identification of the Conservation of Heritage Buildings

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