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1
Calvo-Lobo, Cesar, Marta San-Antolín, Daniel García-García, Ricardo Becerro-de-Bengoa-Vallejo, Marta Elena Losa-Iglesias, Julia Cosín-Matamoros, Israel Casado-Hernández, Eva María Martínez-Jiménez, Victoria Mazoteras-Pardo, and David Rodríguez-Sanz. "Intra- and inter-session reliability and repeatability of an infrared thermography device designed for materials to measure skin temperature of the triceps surae muscle tissue of athletes." PeerJ 11 (March 9, 2023): e15011. http://dx.doi.org/10.7717/peerj.15011.
Анотація:
Background Infrared thermography devices have been commonly applied to measure superficial temperature in structural composites and walls. These tools were cheaper than other thermographic devices used to measure superficial human muscle tissue temperature. In addition, infrared thermography has been previously used to assess skin temperature related to muscle tissue conditions in the triceps surae of athletes. Nevertheless, the reliability and repeatability of an infrared thermography device designed for materials, such as the Manual Infrared Camera PCE-TC 30, have yet to be determined to measure skin temperature of the triceps surae muscle tissue of athletes. Objective The purpose was to determine the procedure’s intra- and inter-session reliability and repeatability to determine skin temperature within the Manual Infrared Camera PCE-TC 30 thermography device in the triceps surae muscle tissue of athletes, which was initially designed to measure the superficial temperature of materials. Methods A total of 34 triceps surae muscles were bilaterally assessed from 17 healthy athletes using the Manual Infrared Camera PCE-TC 30 thermography device to determine intra- (at the same day separated by 1 h) and inter-session (at alternate days separated by 48 h) reliability and repeatability of the skin temperature of the soleus, medial and lateral gastrocnemius muscles. The triceps surae complex weas measured by a region of interest of 1 cm2 through five infrared thermography images for each muscle. Statistical analyses comprised intraclass correlation coefficient (ICC), standard error of measurement (SEM), minimum detectable change (MCD), systematic error of measurement, correlation (r), and Bland-Altman plots completed with linear regression models (R2). Results Intra- and inter-session measurements of the proposed infrared thermography procedure showed excellent reliability (ICC(1,2) = 0.968–0.977), measurement errors (SEM = 0.186–0.232 °C; MDC = 0.515–0.643 °C), correlations (r = 0.885–0.953), and did not present significant systematic error of measurements (P > 0.05). Adequate agreement between each pair of measurement moments was presented by the Bland-Altman plots according to the limits of agreement and non-significant linear regression models (R2 = 0.000–0.019; P > 0.05). Conclusions The proposed procedure to determine skin temperature within the Manual Infrared Camera PCE-TC 30 thermography device presented excellent intra- and inter-session reliability and repeatability in athletes’ triceps surae muscle tissue. Future studies should consider the SEM and MDC of this procedure to measure the skin temperature of soleus, medial, and lateral gastrocnemius muscles to promote triceps surae muscle prevention and recovery in athletes.
2
Ushiki, Tomohiko, Ryota Imazawa, Hidetoshi Murakami, Kosuke Shimizu, Tatsuo Sugie, and Takaki Hatae. "Dual two-color method: A new concept of ultra-wide temperature range thermography (200–3600 °C) for ITER divertor infrared thermography." Review of Scientific Instruments 93, no. 8 (August 1, 2022): 084905. http://dx.doi.org/10.1063/5.0089269.
Анотація:
A new temperature measurement method—the dual two-color method—was developed to accurately measure the temperature over an ultra-wide temperature range (200–3600 °C) for ITER divertor infrared thermography. This novel method introduces a third wavelength filter to the conventional two-color method by replacing the shorter single wavelength bandpass filter with a customized dual-bandpass filter having two transmission bands, without having to add a third infrared camera. The dominant wavelength band of the total radiance through the dual-band filter changes automatically as the temperature increases and, consequently, either the shorter or longer wavelength band of the dual-bandpass filter is used to establish the two-color combination at both low and high temperatures. The dual two-color method increased the acceptable measurement error of the two-color radiance ratio for the temperature measurement requirement of the ITER divertor infrared thermography to 9.45% from that of 4.3% when using the conventional two-color method.
3
Kolosovas-Machuca, Eleazar S., Mario A. Martínez-Jiménez, José L. Ramírez-GarcíaLuna, Francisco J. González, Amaury J. Pozos-Guillen, Nadia P. Campos-Lara, and Mauricio Pierdant-Perez. "Pain Measurement through Temperature Changes in Children Undergoing Dental Extractions." Pain Research and Management 2016 (2016): 1–5. http://dx.doi.org/10.1155/2016/4372617.
Анотація:
Background and Objective.Pain evaluation in children can be a difficult task, since it possesses sensory and affective components that are often hard to discriminate. Infrared thermography has previously been used as a diagnostic tool for pain detection in animals; therefore, the aim of this study was to assess the presence of temperature changes during dental extractions and to evaluate its correlation with heart rate changes as markers of pain and discomfort.Methods. Thermographic changes in the lacrimal caruncle and heart rate measurements were recorded in healthy children scheduled for dental extraction before and during the procedure and compared. Afterwards, correlation between temperature and heart rate was assessed.Results. We found significant differences in temperature and heart rate before the procedure and during the dental extraction (mean difference 4.07°C,p<0.001, and 18.11 beats per minute,p<0.001) and no evidence of correlation between both measurements.Conclusion. Thermographic changes in the lacrimal caruncle can be detected in patients who undergo dental extractions. These changes appear to be stable throughout time and to possess very little intersubject variation, thus making them a candidate for a surrogate marker of pain and discomfort. Future studies should be performed to confirm this claim.
4
López-Fernández, L., S. Lagüela, D. González-Aguilera, and H. Lorenzo. "Thermographic and mobile indoor mapping for the computation of energy losses in buildings." Indoor and Built Environment 26, no. 6 (March 15, 2016): 771–84. http://dx.doi.org/10.1177/1420326x16638912.
Анотація:
A mobile indoor mapping system combined with infrared thermography was used for the acquisition of data needed for the quantification of heat loss through a building envelope by conduction; that is, temperature values and building geometry. The methodology presented orthothermograms to provide measurement of heat loss and thermographic images with geometric information. This way, not only the energy loss through the building envelope is provided, but also thermographic information regarding the existence of thermal pathologies, their location and their impact on the building can also be evaluated.
5
Kim, Jeong Guk, Seung Koo Baek, Chang Young Lee, and Sung Cheol Yoon. "Deterioration and Thermographic Analyses of Electrical Units in Diesel Locomotive." Key Engineering Materials 417-418 (October 2009): 729–32. http://dx.doi.org/10.4028/www.scientific.net/kem.417-418.729.
Анотація:
The electrical units of diesel electric locomotives, which were used for over 30 years, were characterized for deterioration evaluation through insulation resistance measurement, degradation testing, and infrared thermography method. Especially, an infrared camera and thermocouples were employed for the evaluation. The thermocouples were attached on high-voltage cables connected to traction motors, for in-situ measurement of abnormal heating during test running. After test running, the thermographic images were obtained for the inspection of high-voltage cables using the infrared camera. The thermographic results were quantitatively analyzed, and compared with temperature changes during running. In this investigation, various analysis techniques for the safety characterization of diesel electric locomotives have been introduced, and the analysis results have been used to provide the deterioration or wear information in current locomotive systems.
6
Ren, Chao, Libing Bai, Ruilong Shi, Jie Zhang, Xu Zhang, and Cong Chen. "Measurement of current distribution using infrared thermography." Review of Scientific Instruments 94, no. 3 (March 1, 2023): 034713. http://dx.doi.org/10.1063/5.0137203.
Анотація:
Current distribution measurement methods are widely used in medical examinations, predicting faults in semiconductor devices and assessing structural integrity. Several methods for measuring current distribution are available, such as electrode arrays, coils, and magnetic sensors. However, these measurement methods are unable to obtain images of current distribution with high spatial resolution. Therefore, there is a need to develop a non-contact method to measure current distribution that is capable of capturing images with high spatial resolution. In this study, a non-contact current distribution measurement method based on infrared thermography is proposed. The method uses thermal variations to quantify the current amplitude and reconstructs the current direction based on the passivity of the electric field. For quantification of low frequency current amplitude, the experimental results show that the method can provide accurate current measurement results, for example, at the power frequency (50 Hz), in the range of 1.05–3.45 A, its relative error can be improved to ±3.66% when the calibration fitting method is used. For the high-frequency current, an effective estimate of the current amplitude is obtained using the first-order derivative of temperature variation. When applied to the eddy current detection (256 KHz), it achieves a high-resolution image of the current distribution, and the effectiveness of the method is verified through simulation experiments. The experimental results show that the proposed method not only measures the current amplitude accurately but also improves the spatial resolution in acquiring two-dimensional current distribution images.
7
Kim, Won Tae, Man Yong Choi, and Jung Hak Park. "NDT Analysis of Metal Materials with Internal Defects Using Active Infrared Thermography Method." Key Engineering Materials 321-323 (October 2006): 835–40. http://dx.doi.org/10.4028/www.scientific.net/kem.321-323.835.
Анотація:
This study is aimed to analyze the thermal imaging patterns presented by infrared(IR) thermography at which the metal with internal defects are thermally heated. Through the knowledge of non-destructive testing which infrared thermography can be applied to detect the defects inside the materials, there are two materials experimented; one is stainless steel and the other is cast-iron. Thermally, each material of specimens is heated at the base of the material and kept with constant temperature, The artificial defects in the specimen are formulated. Under the shape and location of the defects, temperature profiles are also measured and validated using the computer simulation. It is concluded that the characteristics of thermal patterns obtained from IR thermography are consistent with those of measurement and computations.
8
Harrap, Michael J. M., Natalie Hempel de Ibarra, Heather M. Whitney, and Sean A. Rands. "Reporting of thermography parameters in biology: a systematic review of thermal imaging literature." Royal Society Open Science 5, no. 12 (December 2018): 181281. http://dx.doi.org/10.1098/rsos.181281.
Анотація:
Infrared (IR) thermography, where temperature measurements are made with IR cameras, has proven to be a very useful and widely used tool in biological science. Several thermography parameters are critical to the proper operation of thermal cameras and the accuracy of measurements, and these must usually be provided to the camera. Failure to account for these parameters may lead to less accurate measurements. Furthermore, the failure to provide information of parameter choices in reports may compromise appraisal of accuracy and replicate studies. In this review, we investigate how well biologists report thermography parameters. This is done through a systematic review of biological thermography literature that included articles published between years 2007 and 2017. We found that in primary biological thermography papers, which make some kind of quantitative temperature measurement, 48% fail to report values used for emissivity (an object's capacity to emit thermal radiation relative to a black body radiator), which is the minimum level of reporting that should take place. This finding highlights the need for life scientists to take into account and report key parameter information when carrying out thermography, in the future.
9
Wang, Xiaoshuai, Feiyue Hu, Ruimin Yang, and Kaiying Wang. "An Infrared Temperature Correction Method for the Skin Temperature of Pigs in Infrared Images." Agriculture 13, no. 3 (February 21, 2023): 520. http://dx.doi.org/10.3390/agriculture13030520.
Анотація:
Accurately measuring the skin temperature of pigs is essential to large-scale pig farming for health monitoring, as well as disease detection and prevention. Infrared thermography (IRT) is a promising technology for the non-invasive measuring of pig skin temperature. However, the distance and angle of view of measurement greatly affect the accuracy of IRT-measured temperature. To improve the accuracy of the measurement, this study starts with evaluating the effects of four parameters on the measurement of skin temperature: horizontal distance, camera height, pig height, and angle of view between the object and the IRT camera. It follows by proposing a mathematical model describing the relationship between the real skin temperature and the four parameters through means of response surface methodology. A correction algorithm is then developed based on the mathematical model to improve the measuring accuracy. In order to evaluate the performance of the correction algorithm, the measured skin temperatures before and after correction are compared with the actual ones. The comparison was carried out in an experimental pig farm with 25 randomly selected pigs. The results show that the mean relative error before the correction was −4.64% and the mean relative error after the correction was −0.70%. This study demonstrates that the new infrared temperature correction method is effective and can benefit skin temperature monitoring for commercial pig farms.
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Mineo, Simone, and Giovanna Pappalardo. "Rock Emissivity Measurement for Infrared Thermography Engineering Geological Applications." Applied Sciences 11, no. 9 (April 22, 2021): 3773. http://dx.doi.org/10.3390/app11093773.
Анотація:
Infrared thermography is a growing technology in the engineering geological field both for the remote survey of rock masses and as a laboratory tool for the non-destructive characterization of intact rock. In this latter case, its utility can be found either from a qualitative point of view, highlighting thermal contrasts on the rock surface, or from a quantitative point of view, involving the study of the surface temperature variations. Since the surface temperature of an object is proportional to its emissivity, the knowledge of this last value is crucial for the correct calibration of the instrument and for the achievement of reliable thermal outcomes. Although rock emissivity can be measured according to specific procedures, there is not always the time or possibility to carry out such measurements. Therefore, referring to reliable literature values is useful. In this frame, this paper aims at providing reference emissivity values belonging to 15 rock types among sedimentary, igneous and metamorphic categories, which underwent laboratory emissivity estimation by employing a high-sensitivity thermal camera. The results show that rocks can be defined as “emitters”, with emissivity generally ranging from 0.89 to 0.99. Such variability arises from both their intrinsic properties, such as the presence of pores and the different thermal behavior of minerals, and the surface conditions, such as polishing treatments for ornamental stones. The resulting emissivity values are reported and commented on herein for each different studied lithology, thus providing not only a reference dataset for practical use, but also laying the foundation for further scientific studies, also aimed at widening the rock aspects to investigate through IRT.
11
Salopek-Čubrić, Ivana, Dominika Rosić, and Antonija Petrov. "Improvement of thermophysiological comfort of athletes based on thermographic evaluation of sportswear material." Advanced Technologies 11, no. 2 (2022): 55–61. http://dx.doi.org/10.5937/savteh2202055s.
Анотація:
Thermography is a widely used method of measuring surface temperature and its distribution. It is based on the measurement of the radiation intensity in the infrared region of the electromagnetic spectrum. Infrared thermography is applicable in all spheres of human activity because it broadens the world's view and irreversibly changes the notion of space that surrounds us. One of the important issues in professional sports is maintaining the optimal level of comfort during intense sports activities. Therefore, this paper aims to investigate the possibilities of the application of thermography for testing the properties related to the comfort of athletes focusing on the transfer of liquid (sweat) through the materials intended for making sportswear. Moreover, the accent is given to the comparison of non-aged materials, and materials aged applying different protocols characteristic for football sportswear.
12
Bauer, Elton, Vasco Peixoto de Freitas, Niubis Mustelier, Eva Barreira, and Sara Stingl de Freitas. "Infrared thermography – evaluation of the results reproducibility." Structural Survey 33, no. 1 (April 13, 2015): 20–35. http://dx.doi.org/10.1108/ss-05-2014-0021.
Анотація:
Purpose – Infrared thermography is increasingly being used to diagnose pathologies in buildings, such as façade defects. The purpose of this paper is to assess the results reproducibility and the equipment influence on the measurements. To do so, it was defined as case study the assessment of rendering delamination. Design/methodology/approach – Two infrared cameras of different makers were used to detect the presence of defects deliberately created in specimens. The tests were done in the laboratory with a heat source. The defects were detected through a temperature gradient between the zones with and without defect. Findings – With this thermographic imaging, it was possible to identify the defects in the specimen both qualitatively and quantitatively. The results were found to be reproducible in the three cycles performed. The influence of the equipment on the results was of little significance for the quantitative assessment criterion “temperature difference between zones with and without defect”, but for the criterion “absolute surface temperature”, the difference in the results yielded by the two cameras was around 1.8°C. Originality/value – The results suggest that there is reproducibility of the measurements, considering both the qualitative and quantitative approach, when assessing delamination, irrespective of the maker of the equipment used. The influence of the equipment on the results depends on the quantitative assessment criterion used.
13
Guimarães, Bruno, José Rosas, Cristina M. Fernandes, Daniel Figueiredo, Hernâni Lopes, Olga C. Paiva, Filipe S. Silva, and Georgina Miranda. "Real-Time Cutting Temperature Measurement in Turning of AISI 1045 Steel through an Embedded Thermocouple—A Comparative Study with Infrared Thermography." Journal of Manufacturing and Materials Processing 7, no. 1 (February 15, 2023): 50. http://dx.doi.org/10.3390/jmmp7010050.
Анотація:
During machining processes, a high temperature is generated in the cutting zone due to deformation of the material and friction of the chip along the surface of the tool. This high temperature has a detrimental effect on the cutting tool, and for this reason, it is of the utmost importance to assess the cutting temperature in real time during these processes. Despite all the advances and investigation in this field, accurately measuring the cutting temperature remains a great challenge. In this sense, this work intends to contribute to solving this problem by experimentally evaluating the potential of the developed approach for embedding thermocouples into the rake face of cutting tools for measuring cutting temperature in real time during dry turning of AISI 1045 steel for different cutting parameters and comparing the obtained results with infrared thermography measurements at the exact same point. A well-defined, smooth micro-groove with good surface quality was produced by laser surface modification. Then a laser-welded K-type thermocouple was fixated in the micro-groove with a MgO ceramic adhesive, ensuring protection from wear and chips, which allowed the creation of WC-Co cutting inserts with the ability to measure cutting tool temperature with a maximum error of 0.96%. Results showed that, despite yielding the same trend, the tool temperature measured by the IR thermographic camera was always lower than the temperature measured by the K-type embedded thermocouple. The proposed embedded thermocouple method proved to be a reliable, precise, accurate, and cost-effective approach for real-time temperature measurement capable of providing useful information for cutting parameter optimization, thus allowing increased productivity and tool life.
14
Chen, Wei, Kesen Wei, Jincheng Wei, Wenyang Han, Xiaomeng Zhang, Guiling Hu, Shuaishuai Wei, et al. "Research on the Road Performance of Asphalt Mixtures Based on Infrared Thermography." Materials 15, no. 12 (June 17, 2022): 4309. http://dx.doi.org/10.3390/ma15124309.
Анотація:
Temperature segregation during the paving of asphalt pavements is one of the causes of asphalt pavement distress. Therefore, controlling the paving temperature is crucial in the construction of asphalt pavements. To quickly evaluate the road performance of asphalt mixtures during paving, in this work, we used unmanned aerial vehicle infrared thermal imaging technology to monitor the construction work. By analyzing the temperature distribution at the paving site, and conducting laboratory tests, the relationship between the melt temperature, high-temperature stability, and water stability of the asphalt mix was assessed. The results showed that the optimal temperature measurement height for an unmanned aerial vehicle (UAV) with an infrared thermal imager was 7–8 m. By coring the representative temperature points on the construction site and then conducting a Hamburg wheel tracking (HWT) test, the test results were verified through the laboratory test results in order to establish a prediction model for the melt temperature and high-temperature stability of y = 10.73e0.03x + 1415.78, where the predictive model for the melt temperature and water was y = −19.18e−0.02x + 98.03. The results showed that using laboratory tests combined with UAV infrared thermography could quickly and accurately predict the road performance of asphalt mixtures during paving. We hope that more extensive evaluations of the roadworthiness of asphalt mixtures using paving temperatures will provide reference recommendations in the future.
15
Kaewwichit, Jesada, Rittichai Phaoniam, and Bovornchok Poopat. "Interference Phenomena on Infrared Thermography during a Mushy Solidification Zone." Materials Science Forum 1053 (February 17, 2022): 191–98. http://dx.doi.org/10.4028/p-74ao5q.
Анотація:
This research aims to investigate the interference phenomena on a mushy zone during weld solidification using infrared thermography. Stationary heating source was carried out on a low carbon steel through GTAW process. The different spot-heating sequences were studied, namely, single and double melting steps. Surface preparation of a specimen was divided into two (2) cases, firstly a non-grinded surface and secondly a grinded surface. Thermocouples of three (3) points were attached nearby liquid-solid state region in order to verify an appropriate emissivity coefficient of a high-temperature mushy zone. As the result, in the case of non-grinded surface specimen with immediately spot-melting double steps exhibited that the infrared images were strongly interfered from an oxide film formation. Such an oxidized surface moved randomly around the molten pool margin. As for the grinded surface specimen with spot-melting double steps, it revealed the first-spot melting step was notably clear infrared images. However, the second-spot melting step exhibited the interference phenomena from the first-melted surface region. Such the surface region affected on the proper heat transfer emissivity coefficient of high temperature. The grinded surface with single melting step was able to attain clear infrared images. Therefore, the corrected temperature of a mushy zone was determined by approximate constant emissivity coefficient of 0.23. Additionally, more accurate temperature measurement of entire region was done with emissivity coefficient depended on temperature.
16
Živanović, Nevena, Marina Aškrabić, Aleksandar Savić, Miša Stević, and Zoran Stević. "Early-Age Cement Paste Temperature Development Monitoring Using Infrared Thermography and Thermo-Sensors." Buildings 13, no. 5 (May 19, 2023): 1323. http://dx.doi.org/10.3390/buildings13051323.
Анотація:
Infrared thermography is an advanced technique usually applied for the assessment of thermal losses through different elements of the building envelope, or as a method for detection of damage (cracks) in reinforced concrete elements, such as bridges. Use of this method for the investigation of temperature development during early cement hydration is still an evolving area of research. For the purpose of verifying the reliability of the method, two types of cubic samples of different heights were prepared using a cement-based paste, with 20% of cement (by mass) replaced with fly ash. Temperature development was measured in two ways: using infrared thermography and thermo-sensors embedded in the samples. Additionally, the obtained results were modeled using the asymmetric Gaussian function. Peak temperatures in the middle of each sample were higher than the peak temperatures measured on the sample surface, with differences ranging between 2 °C and 4 °C. Differences between the temperature measurements of the thermo-sensors placed on the surface of the sample and thermal camera were lower than 2 °C. Very good compliance of the results was obtained for both the camera and the surface sensors measurements, as well as for the modeling coefficients.
17
Denoble, Anna E., Norine Hall, Carl F. Pieper, and Virginia B. Kraus. "Patellar Skin Surface Temperature by Thermography Reflects Knee Osteoarthritis Severity." Clinical Medicine Insights: Arthritis and Musculoskeletal Disorders 3 (January 2010): CMAMD.S5916. http://dx.doi.org/10.4137/cmamd.s5916.
Анотація:
Background Digital infrared thermal imaging is a means of measuring the heat radiated from the skin surface. Our goal was to develop and assess the reproducibility of serial infrared measurements of the knee and to assess the association of knee temperature by region of interest with radiographic severity of knee Osteoarthritis (rOA). Methods A total of 30 women (15 Cases with symptomatic knee OA and 15 age-matched Controls without knee pain or knee OA) participated in this study. Infrared imaging was performed with a Meditherm Med2000™ Pro infrared camera. The reproducibility of infrared imaging of the knee was evaluated through determination of intraclass correlation coefficients (ICCs) for temperature measurements from two images performed 6 months apart in Controls whose knee status was not expected to change. The average cutaneous temperature for each of five knee regions of interest was extracted using WinTes software. Knee x-rays were scored for severity of rOA based on the global Kellgren-Lawrence grading scale. Results The knee infrared thermal imaging procedure used here demonstrated long-term reproducibility with high ICCs (0.50–0.72 for the various regions of interest) in Controls. Cutaneous temperature of the patella (knee cap) yielded a significant correlation with severity of knee rOA (R = 0.594, P = 0.02). Conclusion The skin temperature of the patellar region correlated with x-ray severity of knee OA. This method of infrared knee imaging is reliable and as an objective measure of a sign of inflammation, temperature, indicates an interrelationship of inflammation and structural knee rOA damage.
18
Aryani, Any, Dedy Duryadi Solihin, Cece Sumantri, Rudi Afnan, and Tike Sartika. "Respons Fisiologis Ayam KUB (Kampung Unggul Balitbangtan) dan Ayam Walik dengan Haplotipe Gen HSP70 Berbeda yang Terpapar Cekaman Panas Akut." Jurnal Ilmu Pertanian Indonesia 26, no. 2 (April 29, 2021): 276–83. http://dx.doi.org/10.18343/jipi.26.2.276.
Анотація:
This study was conducted to determine the physiological response of acute heat stress in Kampung Unggul Balitbangtan (KUB) and Walik chickens with four different HSP70 gene haplotypes (H1', H1, H2, and H3). Acute heat stress is carried out at 35°C for one hour. The data was analyzed based on rectal temperature measurements, distribution of body surface temperature (head, neck, body, and leg area), hormone levels (corticosterone and triiodothyronine), and time of panting. Body surface temperature is detected using infrared thermography. The results showed that haplotype H1 Walik chicken is more susceptible to heat stress based on the rectal temperature. In contrast, H1' haplotype Walik chicken released more heat through the body surface in the leg area.
Keywords: heat stress, hormone, KUB chicken, infrared thermography, walik chicken
19
Doshvarpassand, Siavash, and Xiangyu Wang. "Sub-Surface Defect Depth Approximation in Cold Infrared Thermography." Sensors 22, no. 18 (September 19, 2022): 7098. http://dx.doi.org/10.3390/s22187098.
Анотація:
Detection and characterisation of hidden corrosion are considered challenging yet crucial activities in many sensitive industrial plants where preventing the loss of containment or structural reliability are paramount. In the last two decades, infrared (IR) thermography has proved to be a reliable means for inspection of corrosion or other sub-surface anomalies in low to mid thickness metallic mediums. The foundation of using IR thermography for defect detection and characterisation is based on active thermography. In this method of inspection, an external excitation source is deployed for the purpose of stimulating thermal evolutions inside objects. The presence of sub-surface defects disrupts the evolution of electromagnetic pulse inside an object. The reflection of altered pulse at the surface can be recorded through thermal camera in the form of temperature anomalies. Through authors’ previous works, cold thermography has shown that it can be a viable defect detection alternative to the most commonly used means of active thermography, known as heating. In the current work, the characterisation of defect dimensions, i.e., depth and diameter, has been explored. A simple analytical model for thermal contrast over defect is used in order to approximate the defect depth and diameter. This is achieved by comparing the similarities of the model and the experimental contrast time-series. A method of time-series similarity measurement known as dynamic time wrapping (DTW) is used to score the similarity between a pair of model and experiment time-series. The final outcome of the proposed experimental setup has revealed that there is a good potential to predict the metal loss of up to 50% in mid-thickness substrate even by deploying a less accurate nonradiometric thermal device and no advanced image processing.
20
Stojek, Krzysztof Jakub, Jan Felba, Johann Nicolics, and Dominik Wołczyński. "Impact of convection on thermographic analysis of silver based thermal joints." Soldering & Surface Mount Technology 32, no. 4 (May 28, 2020): 241–46. http://dx.doi.org/10.1108/ssmt-11-2019-0040.
Анотація:
Purpose This paper aims to develop thermal analysis method of thermal joints characterization. The impact on convection on thermal resistance analysis with use thermography for silver-based thermal joints were investigated for non-metallized and metalized semiconductor surfaces. Heat transfer efficiency depends on thermal conductivity; radiation was used to perform thermographic analysis; the convection is energy loss, so its removing might improve measurements accuracy. Design/methodology/approach Investigation of thermal joints analysis method was focused on determination of convection impact on thermal resistance thermographic analysis method. Measuring samples placed in vacuum chamber with lowered pressure requires transparent window for infrared radiation that is used for thermographic analysis. Impact of infrared window and convection on temperature measurements and thermal resistance were referred. Findings The results showed that the silicon window allowed to perform thermal analysis through, and the convection was heat transfer mode which create 15% energy loss. Originality/value It is possible to measure thermal resistance for silver-based thermal joints with convection eliminated to improve measurements accuracy.
21
Grechi, Guglielmo, Matteo Fiorucci, Gian Marco Marmoni, and Salvatore Martino. "3D Thermal Monitoring of Jointed Rock Masses through Infrared Thermography and Photogrammetry." Remote Sensing 13, no. 5 (March 4, 2021): 957. http://dx.doi.org/10.3390/rs13050957.
Анотація:
The study of strain effects in thermally-forced rock masses has gathered growing interest from engineering geology researchers in the last decade. In this framework, digital photogrammetry and infrared thermography have become two of the most exploited remote surveying techniques in engineering geology applications because they can provide useful information concerning geomechanical and thermal conditions of these complex natural systems where the mechanical role of joints cannot be neglected. In this paper, a methodology is proposed for generating point clouds of rock masses prone to failure, combining the high geometric accuracy of RGB optical images and the thermal information derived by infrared thermography surveys. Multiple 3D thermal point clouds and a high-resolution RGB point cloud were separately generated and co-registered by acquiring thermograms at different times of the day and in different seasons using commercial software for Structure from Motion and point cloud analysis. Temperature attributes of thermal point clouds were merged with the reference high-resolution optical point cloud to obtain a composite 3D model storing accurate geometric information and multitemporal surface temperature distributions. The quality of merged point clouds was evaluated by comparing temperature distributions derived by 2D thermograms and 3D thermal models, with a view to estimating their accuracy in describing surface thermal fields. Moreover, a preliminary attempt was made to test the feasibility of this approach in investigating the thermal behavior of complex natural systems such as jointed rock masses by analyzing the spatial distribution and temporal evolution of surface temperature ranges under different climatic conditions. The obtained results show that despite the low resolution of the IR sensor, the geometric accuracy and the correspondence between 2D and 3D temperature measurements are high enough to consider 3D thermal point clouds suitable to describe surface temperature distributions and adequate for monitoring purposes of jointed rock mass.
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Dunand-Châtellet, Clement, and Ziad Moumni. "Coupling Infrared Thermography and Acoustic Emission Measurement to Quantify the Shakedown State of Shape Memory Alloys." Key Engineering Materials 488-489 (September 2011): 146–49. http://dx.doi.org/10.4028/www.scientific.net/kem.488-489.146.
Анотація:
This paper provides an original experimental characterization of the shakedown state of a shape memory alloy structure under cyclic pseudo-elastic loading. This analysis is performed through the observation of the dissipated energy at a macroscopic scale as well as the temperature on the surface of the sample through infrared thermography measurement. Morevover, a deeper study is led thanks to acoustic emission to quantify the shifts between microscopic evolutions at a lower scale. The main conclusion is that these 3 quantities are correlated and enable us to identify different stages the structure crosses until the shakedown state.
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Neubauer, Moritz, Martin Dannemann, Niklas Herzer, Benjamin Schwarz, and Niels Modler. "Analysis of a Film Forming Process through Coupled Image Correlation and Infrared Thermography." Polymers 14, no. 6 (March 18, 2022): 1231. http://dx.doi.org/10.3390/polym14061231.
Анотація:
The aim of the present investigation was to determine the dependence of the material and process parameters of the bending process of thermoplastic films. In this context, parameter combinations leading to high resulting forming ratios were identified. To measure the relevant parameters within the hot bending process, a coupled evaluation of infrared thermography (IRT) and deformation measurement using digital image correlation (DIC) was performed. The coupled measurement enables the identification of the actual mechanically stressed bending area of the film as a result of the bending process. This allows for the specification of the local forming temperatures required for the desired forming ratios. Furthermore, the mechanical and thermal strain along the defined measuring sections and their deviation in individual tests as well as the effect of thermal strain on process control on a larger scale were determined. Based on the results, a process window was defined for the film materials investigated, which will serve as a starting point for future efforts to develop a continuous manufacturing process.
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Kesztyüs, Dorothea, Sabrina Brucher, and Tibor Kesztyüs. "Use of infrared thermography in medical diagnostics: a scoping review protocol." BMJ Open 12, no. 4 (April 2022): e059833. http://dx.doi.org/10.1136/bmjopen-2021-059833.
Анотація:
IntroductionThermography offers a non-invasive radiation-free methodology for diagnostic imaging and temperature measurement, but the extent of the current application is unclear, as is the level of evidence for each use case. Moreover, population-based thermographic reference values for diagnostic purposes are nearly unknown. The aim of this scoping review is to identify patient populations and diseases in which thermography is applied, cataloguing of technical and environmental modalities, investigation of the existence of specific reference data and finally exploration of gaps and future tasks.Methods and analysisPubMed, Cochrane Database of Systematic Reviews and CENTRAL, Embase, Web of Science and OpenGrey are to be searched using pretested suitable search strategies, with no language restriction, but abstracts should be available in English or German and articles should not have been published before 2000. This limited time frame is due to the rapid technological progress, which makes it necessary to exclude reports based on outdated technology. The literature found will be selected on the basis of previously defined inclusion and exclusion criteria. Subsequently, relevant data will be extracted from the included references into a predesigned table. The selection and extraction process will be conducted by two researchers independently. The report of the results will be according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist. The entire review process will follow the Joanna Briggs Institute approach. The scoping review protocol is registered at the Open Science Framework.Ethics and disseminationEthical approval is not required for this work, but ethical medicine also obliges us to carefully consider diagnostic alternatives and compare them with current standards. The dissemination of the results will take place in a variety of ways. First and foremost through publication in an open access journal, but also through conference proceedings. In addition, this scoping review will serve to open up new research foci with regard to thermography.
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Markham, Sarah K., Aladin Mani, Elena A. Korsakova, Aleksandr S. Korsakov, Liya V. Zhukova, Joanna Bauer, Christophe Silien, and Syed A. M. Tofail. "Polarisation changes in guided infrared thermography using silver halide poly-crystalline mid-infrared fibre bundle." Journal of Thermal Analysis and Calorimetry 142, no. 2 (July 22, 2020): 1115–22. http://dx.doi.org/10.1007/s10973-020-10018-0.
Анотація:
Abstract Broadband mid-infrared (B-MIR) thermography using fibre optic waveguides can be critical in real-time imaging in harsh environments such as additive manufacturing, personalised medical diagnosis and therapy. We investigate the polarisation effect on thermal measurements through poly-crystalline fibre bundle employing a simple broadband cross-polarisation configuration experimental set-up. Silver halide poly-crystalline fibres AgCl1−xBrx (0 ≤ x≤1) (AgClBr-PolyC) have very wide transmission bandwidth spanning over the spectral range from 1 µm up to 31 µm FWHM. Moreover, they are non-toxic, non-hygroscopic, with relatively good flexibility, which make them very adequate for spectroscopic and thermal measurements in medical and clinical fields. In this study, we used a fibre bundle composed of seven single AgClBr-PolyC fibres, each with a core diameter of about 300 µm, inserted between two broadband MIR polarisers. A silicon carbide filament source was placed at the entrance of the fibre bundle, while a FLIR thermal camera with a close-up lens was employed to measure the spatial temperature distribution over the fibre-bundle end. Indeed, polarisation dependence of temperature measurements has been clearly observed in which the orientation of temperature extrema (minima and maxima) vary from one fibre to another within the bundle. Moreover, these observations have enabled the classification of AgClBr-PolyC fibres following their polarisation sensitivities by which some fibres are relatively highly sensitive to polarisation with polarisation temperature difference (PTD) that can reach 22.1 ± 2.8 °C, whereas some others show very low PTD values down to 3.1 ± 2.8 °C. Many applications can readily be found based on the advantages of both extreme cases.
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Ekkad, Srinath V., Shichuan Ou, and Richard B. Rivir. "A Transient Infrared Thermography Method for Simultaneous Film Cooling Effectiveness and Heat Transfer Coefficient Measurements From a Single Test." Journal of Turbomachinery 126, no. 4 (October 1, 2004): 597–603. http://dx.doi.org/10.1115/1.1791283.
Анотація:
In film cooling situations, there is a need to determine both local adiabatic wall temperature and heat transfer coefficient to fully assess the local heat flux into the surface. Typical film cooling situations are termed three temperature problems where the complex interaction between the jets and mainstream dictates the surface temperature. The coolant temperature is much cooler than the mainstream resulting in a mixed temperature in the film region downstream of injection. An infrared thermography technique using a transient surface temperature acquisition is described which determines both the heat transfer coefficient and film effectiveness (nondimensional adiabatic wall temperature) from a single test. Hot mainstream and cooler air injected through discrete holes are imposed suddenly on an ambient temperature surface and the wall temperature response is captured using infrared thermography. The wall temperature and the known mainstream and coolant temperatures are used to determine the two unknowns (the heat transfer coefficient and film effectiveness) at every point on the test surface. The advantage of this technique over existing techniques is the ability to obtain the information using a single transient test. Transient liquid crystal techniques have been one of the standard techniques for determining h and η for turbine film cooling for several years. Liquid crystal techniques do not account for nonuniform initial model temperatures while the transient IR technique measures the entire initial model distribution. The transient liquid crystal technique is very sensitive to the angle of illumination and view while the IR technique is not. The IR technique is more robust in being able to take measurements over a wider temperature range which improves the accuracy of h and η. The IR requires less intensive calibration than liquid crystal techniques. Results are presented for film cooling downstream of a single hole on a turbine blade leading edge model.
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Peterson, Michael P., Matthew A. Firpo, Irma D. Fleming, Clement Vachet, Zachary T. Huston, Emily M. Graham, and Giavonni Lewis. "54 Validation of Infrared Thermography for Prediction of 21-day Burn Wound Healing." Journal of Burn Care & Research 41, Supplement_1 (March 2020): S35—S36. http://dx.doi.org/10.1093/jbcr/iraa024.058.
Анотація:
Abstract Introduction Although trained specialists easily identify most full and superficial partial thickness burn injuries, deep partial-thickness injuries present a true challenge to the clinician. Various imaging modalities to assess perfusion and determine healing potential include skin biopsy with histology, laser doppler imaging, active dynamic and static infrared thermography, vital dyes, indocyanine green video angiography and others. Prior studies indicate, with small clinical and animal studies, forward looking infrared is a valid tool to assess healing potential and 21-day healing within the first 48 hrs after presentation. The aim of our study is to determine if an absolute increase or decrease in temperature (°C) measurements across a burn wound in a large clinical cohort correlates with 21-day healing after 48 hrs from time of injury. Methods After informed photo consent was obtained, thermographic images were captured at presentation, 24hrs, and 48hrs from patients admitted to our center between October 2018 and August 2019. Thermographic images were reviewed and temp measurements obtained using a linear vector through the wound. Next we determined if patients healed within 21 days. Data collected includes demographic data, burn characteristics, injury site (based on Lund Browder segmentation) and wound temp (average, minimum, maximum). Data was analyzed using Wilcoxon rank sum test with continuity correction. Results We reviewed images for 159 burn sites from 29 patients, the largest image set to be reviewed to date. The cases were 84% male, the mean and range was 33.1 years (1.7 – 70) for age and 25% (2 – 54.5) for TBSA. We found an average temp difference between 24 hrs – 48 hrs (p-value= 0.007) was significant, and no significant difference in average temp change when evaluating admit – 24 hrs (p-value=0.053) and admit – 48 hrs (p-value=0.316), consistent with predictions of prior studies. Average temp from admit – 24 hrs decreased by 0.86°C in healed (n=48) vs non-healed (n=91); increased on average by 1.25°C in healed (n=39) vs non-healed (n=74) from 24 hrs – 48 hrs; and showed a modest decrease by 0.3°C in healed (n=50) vs non-healed (n=82) when comparing admit 48 hr temp. Conclusions These data demonstrate that burn wound temperature difference between 24 and 48 hours after admittance as measured by infrared thermography correlates with clinical outcomes and 21 day healing. Applicability of Research to Practice Infrared thermography is a validated tool to assess burn depth after 48 hrs. In the future, this modality may impact triage in the military, rural, accidental and non-accidental disasters.
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Mendes, R. P., D. L. F. Pottie, M. Oliveira, L. V. S. Martins, and R. A. M. Ferreira. "AVERAGE TOTAL HEMISPHERIC EMISSIVITY MEASUREMENT IN THE LWIR SPECTRUM FOR ADHESIVE TAPES USED IN THE THERMOGRAPHY TAPE TEST." Revista de Engenharia Térmica 20, no. 1 (April 12, 2021): 19. http://dx.doi.org/10.5380/reterm.v20i1.80441.
Анотація:
Thermographers often use comparative methods to estimate surfaceemissivity. Among the most used is the tape method. In this method a knownemissivity tape in the LWIR (Long Wavelength Infrared) spectrum is placedon the surface to be inspected. After thermal equilibrium, the temperature ofthe tape and the surface under inspection must be the same. In this case, thetemperature observed on the tape is the reference temperature. The emissivityof the surface must then be changed until the reference temperature isreached. It is common practice to admit the value of the emissivity of theadhesive tape as 0.95, there are few studies that present these data withmetrological rigor, which leads to doubts about the emissivity of thecommercial tapes. In this work, experiments were performed on Tekbond,Double A, 3M 101, Rapix, Altape, adhesive tapes for temperatures of 50, 55,60, 65 and 70ºC. An experimental apparatus was developed through which itwas possible to estimate surface reflection, transmission and atmosphericemission for one and two layers of tapes, in order to make emissivitymeasurements possible. Through the data it was possible to statisticallyestimate the LWIR average total hemispheric emissivity as well as theacceptance range to 95% certainty, being therefore equal to ε=0.94±0.03. Itis possible to arm, therefore, that the value of 0.95, usually used as emissivityof the adhesive tape, is extremely reasonable because it is 0.01 of the averagevalue of the Gaussian distribution calculated by this work.
29
Bowers, S., S. Gandy, T. Dickerson, C. Brown, T. Strauch, D. Neuendorff, R. Randel, and S. Willard. "Evaluating velvet antler growth in red deer stags (Cervus elaphus) using hand-held and digital infrared thermography." Canadian Journal of Animal Science 90, no. 1 (March 1, 2010): 13–21. http://dx.doi.org/10.4141/cjas09043.
Анотація:
The objectives of this study were to evaluate whether velvet antler (VA) surface temperature gradients, as measured by either a single-spot infrared temperature (SST) sensor (SSTS; exp. 1) or digital infrared temperature (DIT) imaging (DITI; exp. 2), would pattern VA growth. In exp. 1, growth rates and SST were obtained from yearling (n = 8) and mature (n = 17) red deer stags (Cervus elaphus) every 14 d following eruption through day 56 in yearlings and day 112 in mature stags. In exp. 2, growth rates and DIT (main beam VA base, mid and tip temperatures) were obtained from red deer stags (n = 31) every 14 d following eruption through day 126. Background temperatures were recorded in conjunction with thermal antler measurements. In exp. 1, yearling VA base and tip SST were positively correlated with one another (P < 0.01); however, both measurements were also positively correlated with background SST (P < 0.05). In mature stags, VA base SST paralleled (P < 0.05) background SST measures, while tip SST did not change from day 56 through day 112. In exp. 2, VA DIT changed (P < 0.01) over time and differed (P < 0.01) between base, mid and tip. During the early growth period, VA temperatures increased (P < 0.05) from 38.9 ± 0.2°C at the base to 39.3 ± 0.2°C at the tip of the antler. In contrast, during the late growth period, DIT was higher (P < 0.01) at the base (36.8 ± 0.3°C) than at the tip (35.7 ± 0.3°C) of the antler. In conclusion, SSTS did not have the sensitivity to signify changes in antler growth rates. However, in exp. 2 using DITI, VA thermogenesis paralleled VA growth suggesting that DITI may have value in monitoring VA growth. Key words: Velvet antler, red deer, thermography
30
Calandra, Sara, Irene Centauro, Stefano Laureti, Marco Ricci, Teresa Salvatici, and Stefano Sfarra. "Application of Sonic, Hygrometric Tests and Infrared Thermography for Diagnostic Investigations of Wall Paintings in St. Panfilo’s Church." Applied Sciences 13, no. 12 (June 11, 2023): 7026. http://dx.doi.org/10.3390/app13127026.
Анотація:
Prior to restoration work, the frescoes created at the end of the XV century by the painter Saturnino Gatti (1463–1518) in the apse of the Church of St. Panfilo in Villagrande di Tornimparte (L’Aquila) were the subject of a thorough diagnostic study involving several tests, from in situ non-destructive analysis to laboratory micro-destructive analysis on the collected samples. In this paper, we report the application of the sonic pulse velocity test, hygrometric tests, and infrared thermography to assess the state of conservation of the frescoes, i.e., the combined system of plaster and wall support. The complete analysis of the frescoes’ state of conservation revealed significant insights. The integrity of the plaster was evaluated through sonic pulse velocity tests, which highlighted several areas of detachment or degradation phenomena. Hygrometric analysis described humidity variations, particularly near the boundary between the conch area and the church naves. Passive infrared thermography detected temperature inhomogeneities, emphasizing differences in the wall texture and the masonry structure. Moreover, by comparing sonic pulse velocity and passive thermography images, a certain degree of correlation between hot areas and slow areas in the presence of possible detachments was noticed. In addition, pulse-compression active thermography was applied in a few spots, and for the first time, to the best of our knowledge, the virtual wave concept was applied to the cultural heritage field. This strategy helps in better associating anomalies with depth. The measurement campaign was part of a research project conducted by members of the Italian Association of Archaeometry (AIAr), and the results were compared and integrated with those of other non-destructive and analytical methods.
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Żaba, Krzysztof, Tomasz Trzepieciński, Sandra Puchlerska, Piotr Noga, and Maciej Balcerzak. "Coupled Thermomechanical Response Measurement of Deformation of Nickel-Based Superalloys Using Full-Field Digital Image Correlation and Infrared Thermography." Materials 14, no. 9 (April 23, 2021): 2163. http://dx.doi.org/10.3390/ma14092163.
Анотація:
The paper is devoted to highlighting the potential application of the quantitative imaging technique through results associated with work hardening, strain rate and heat generated during elastic and plastic deformation. The aim of the research presented in this article is to determine the relationship between deformation in the uniaxial tensile test of samples made of 1-mm-thick nickel-based superalloys and their change in temperature during deformation. The relationship between yield stress and the Taylor–Quinney coefficient and their change with the strain rate were determined. The research material was 1-mm-thick sheets of three grades of Inconel alloys: 625 HX and 718. The Aramis (GOM GmbH, a company of the ZEISS Group) measurement system and high-sensitivity infrared thermal imaging camera were used for the tests. The uniaxial tensile tests were carried out at three different strain rates. A clear tendency to increase the sample temperature with an increase in the strain rate was observed. This conclusion applies to all materials and directions of sample cutting investigated with respect to the sheet-rolling direction. An almost linear correlation was found between the percent strain and the value of the maximum surface temperature of the specimens. The method used is helpful in assessing the extent of homogeneity of the strain and the material effort during its deformation based on the measurement of the surface temperature.
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Chen, Wen-Hwa, Hsien-Chie Cheng, and Chih-Han Lin. "On the Thermal Performance Characteristics of Three-Dimensional Multichip Modules." Journal of Electronic Packaging 126, no. 3 (September 1, 2004): 374–83. http://dx.doi.org/10.1115/1.1773198.
Анотація:
The study explores the thermal performance of three-dimensional (3-D), vertically stacked multi-chip modules (the so-called MCM-V) in natural convection through finite element (FE) modeling and experimental validation. A modified Infrared (IR) thermography-based thermal characterization (IRTTC) technique that integrates a 3-D heat conduction FE modeling and a two-phased IR thermography measurement process is proposed. In contrast to the conventional IRTTC technique (Chen et al. [1]), the technique can improve the resolution of the captured thermal images so as to attain better characterization of the chip junction temperature. The effectiveness of the proposed modified IRTTC technique is confirmed by means of the thermal test die (TTD) measurement. Furthermore, for facilitating subsequent parametric thermal design, a direct FE approach (DFEA) is also introduced. The DFEA simply incorporates existing empirical models for heat transfer (HT) coefficients to describe the surface heat transfer to the ambient through convection and radiation in the proposed heat conduction FE model. Through the modified IRTTC technique and the TTD measurement, the validity of the proposed FE modeling, including the proposed heat conduction FE model and the applied empirical models for HT coefficients, is verified. With the validated FE modeling, four different chip stacking structures of MCM-V packages, including the thick-die-attach, pyramid, cross and dummy-die types, are investigated. In addition, some essential design factors, affecting the thermal performance of the MCM-V, are also extensively explored through parametric FE study. Eventually, an extensive thermal design guideline is accordingly provided.
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Dziarski, Krzysztof, and Arkadiusz Hulewicz. "Uncertainty of Thermographic Temperature Measurement of Electric Units Contained in Switchgear." Pomiary Automatyka Robotyka 25, no. 4 (December 7, 2021): 31–36. http://dx.doi.org/10.14313/par_242/31.
Анотація:
The result of the works presented is the uncertainty budget of a thermographic temperature measurement taken through an IR window. The type B uncertainty determination method has been employed. Publication of European Accreditation EA-4/02 has been patterned. Conditions prevailing in course of the thermographic temperature measurement of low-voltage electric units contained in the switchgear were recreated as part of the works. The measurement system has been presented. Components of the infrared radiation reaching the camera lens in case when an IR window was used and when an IR window was not used have been discussed. Uncertainties estimated for the measurement done with an IR window and without an IR window have been compared.
34
Jiang, Peng, Qian Wang, I. Sabariman, and Eckehard Specht. "Experimental Study on Heat Transfer of Pressurized Spray Cooling on the Heated Plate by Using 45° Full Cone Nozzles." Applied Mechanics and Materials 535 (February 2014): 32–36. http://dx.doi.org/10.4028/www.scientific.net/amm.535.32.
Анотація:
Water spray cooling is widely used in many industrial processes to control heat removal from a hot material surface. In this work, pressurized spray nozzle was applied to break film boiling immediately once the quenching process is started. For this purpose, a circular disc made of non-ferrous metals is heated to approximately 850 °C and sprayed on one side by hydraulic nozzle and the temperature distribution with respect to time and space is measured by using Infrared camera. On the other side, the measured surface was coated with graphite paint in order to achieve a high emissivity. By this IR thermography, transient temperature measurement can be carried out within the window of 320 × 80 pixels. The heat transfer was analyzed through 1D method. In this method, the temperature difference between both sides neglected. The local heat transfer can then be calculated from a simple differential energy balance.
35
Pagliarini, L., F. Clemens, F. Bozzoli, L. Cattani, N. Miche, M. Bernagozzi, M. Marengo, A. A. Alqahtani, and V. Bertola. "Infrared measurements of fluid temperature in a polymeric Pulsating Heat Pipe." Journal of Physics: Conference Series 2685, no. 1 (January 1, 2024): 012050. http://dx.doi.org/10.1088/1742-6596/2685/1/012050.
Анотація:
Abstract Pulsating heat pipes are two-phase passive heat transfer devices partially filled with a working fluid in saturation conditions. During operation, supplying heat to one end of the system (named evaporator) results in a local increase in temperature and pressure, which drives the fluid through a transport section (named adiabatic section) towards the cooled, opposite end (named condenser) for effective heat dissipation. The local thermo-fluid dynamic state of the working fluid is sometimes assessed by means of non-intrusive techniques, such as infrared thermography. In this case, the radiative properties of the systems in the infrared spectrum must be known a priori. Nevertheless, since pulsating heat pipes may be manufactured with different materials, wall thicknesses and channel geometries, the radiative properties of the walls and the confined flow are not always known or assessable by means of the available literature. Hence, the work proposes to design a straightforward calibration procedure for quantitative infrared fluid temperature measurements in a polymeric pulsating heat pipe charged with FC-72 and having unknown radiative properties. The emissivity and transmissivity of the walls and confined fluid are estimated with good accuracy. The results will allow repeatable and reliable fluid temperature measurements in future experimentations on the mentioned device.
36
Navarrete-García, Ítalo Humberto, Leonardo Peña Pupo, María Rodríguez-Gámez, Lucio Alfredo Valarezo-Molina, Julio Cesar Mera-Macias, Lenin Agustín Cuenca-Álava, and María Shirlendy Guerrero-Alcívar. "THERMOGRAPHIC STUDY IN THE LODANA-UTM EXTENSION PHOTOVOLTAIC POWER PLANT FOR THE PREVENTION OF BREAKDOWNS." Journal of Law and Sustainable Development 12, no. 2 (February 27, 2024): e3403. http://dx.doi.org/10.55908/sdgs.v12i2.3403.
Анотація:
Objective: Detect the hot spots present in the photovoltaic modules, to know what type of maintenance they need to achieve good energy performance.
Methods: The bibliographic review method, the inductive-deductive and the experimental method were applied, through visual inspection and infrared thermography to determine the number of panels that are affected, using the temperature variation technique.
Results: It was obtained that 7.41% need corrective maintenance, 11.11% preventive maintenance and 81.48% predictive maintenance, this maintenance must be carried out with the objective that the photovoltaic generator does not lose its optimal operability during its work process and decrease its performance, this prediction method is done automatically, the procedure allows you to organize the detection and classification process more effectively.
Conclusions: Thermography is a passive, non-contact measurement method. Thermal images show the temperature distribution on the surface of the object. Thermal imaging technology has become one of the most valuable diagnostic tools for predictive maintenance by detecting anomalies that are not normally visible to the naked eye. These can prevent costly system failures before they occur, thereby achieving that reduces the occurrence of breakdowns, increases the overall performance factor, improves the profitability conditions of the project, reduces costs associated with its operation.
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Messmer, Jérôme, and Alexander Raphael Groos. "A low-cost and open-source approach for supraglacial debris thickness mapping using UAV-based infrared thermography." Cryosphere 18, no. 2 (February 19, 2024): 719–46. http://dx.doi.org/10.5194/tc-18-719-2024.
Анотація:
Abstract. Debris-covered glaciers exist in many mountain ranges and play an important role in the regional water cycle. However, modelling the surface mass balance, runoff contribution and future evolution of debris-covered glaciers is fraught with uncertainty as accurate observations on small-scale variations in debris thickness and sub-debris ice melt rates are only available for a few locations worldwide. Here we describe a customised low-cost unoccupied aerial vehicle (UAV) for high-resolution thermal imaging of mountain glaciers and present a complete open-source pipeline that facilitates the generation of accurate surface temperature and debris thickness maps from radiometric images. First, a radiometric orthophoto is computed from individual radiometric UAV images using structure-from-motion and multi-view-stereo techniques. User-specific calibration and correction procedures can then be applied to the radiometric orthophoto to account for atmospheric and environmental influences that affect the radiometric measurement. The thermal orthophoto reveals distinct spatial variations in surface temperature across the surveyed debris-covered area. Finally, a high-resolution debris thickness map is derived from the corrected thermal orthophoto using an empirical or inverse surface energy balance model that relates surface temperature to debris thickness and is calibrated against in situ measurements. Our results from a small-scale experiment on the Kanderfirn (also known as Kander Neve) in the Swiss Alps show that the surface temperature and thickness of a relatively thin debris layer (ca. 0–15 cm) can be mapped with high accuracy using an empirical or physical model. On snow and ice surfaces, the mean deviation of the mapped surface temperature from the melting point (∼ 0 ∘C) was 0.6 ± 2.0 ∘C. The root-mean-square error of the modelled debris thickness was 1.3 cm. Through the detailed mapping, typical small-scale debris features and debris thickness patterns become visible, which are not spatially resolved by the thermal infrared sensors of current-generation satellites. The presented approach paves the way for comprehensive high-resolution supraglacial debris thickness mapping and opens up new opportunities for more accurate monitoring and modelling of debris-covered glaciers.
38
Xue, Chao, Yinqiang Zhang, Song Ding, Cheng Song, and Yiqing Wang. "Comparison Research on Characterization and Evaluation Approaches for Paint Coated Corrosion Using Eddy Current Pulsed Thermography." Sensors 23, no. 15 (August 3, 2023): 6889. http://dx.doi.org/10.3390/s23156889.
Анотація:
Paint coated corrosion detection and evaluation is a big challenge for steel performance and structure health. Eddy current pulsed thermography (ECPT) technique is investigated because it can reflect the corrosion physical properties through paint coating by the infrared signal. This paper proposes skewness method, which presents the feature of temperature curve’s shape automatically, and compares it with principal component analysis (PCA), phase analysis, and kurtosis feature extraction methods for paint coated corrosion characterization and evaluation. The averaged skewness shows the best sensitivity for 0–6 months corrosion. The normalized second principal component (PC) presents good sensitivity and the best measurement scale for corroded time. Furthermore, the temperature curve analysis proves that the electrical conductivity dominates the induced heating and heat distribution. The corrosion height is utilized to explain why ECPT technique is valid within 10 months corroded time. ECPT technique is proved as a smart sensor system for paint coated corrosion detection and characterization.
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Glenn, D. Michael. "Infrared and Chlorophyll Fluorescence Imaging Methods for Stress Evaluation." HortScience 47, no. 6 (June 2012): 697–98. http://dx.doi.org/10.21273/hortsci.47.6.697.
Анотація:
Infrared and chlorophyll fluorescence imaging methods are useful techniques to evaluate environmental effects on plant performance. With the advent of digital imaging and advances in sensor technology, infrared (IR) thermography has become more accurate and less expensive. Modern IR cameras can resolve 0.5 °C temperature differences and research-grade instruments can resolve 0.05 °C. This precision has allowed the physical processes of freezing and transpiration to be more accurately studied and modeled. Chlorophyll fluorescence imaging, although still an expensive technology, has also become sufficiently rugged to be useful in the field. The measurement of quantum efficiency, Fv/Fm, provides clear data on the effect of various environmental and biotic effects on the performance of photosynthesis in plants through the effect on photosystem II. Modern digital cameras with low signal-to-noise ratios can also image chlorophyll fluorescence using time lapse exposure. Peltier-cooled charge coupled device (CCD) cameras can measure the autoluminescence in stressed plants that is generated by reactive oxygen species. Advances in technology have reduced the cost and precision of imaging equipment to a point that they are more applicable tools to plant scientists.
40
Maes, Wouter H., Peter E. H. Minchin, William P. Snelgar, and Kathy Steppe. "Early detection of Psa infection in kiwifruit by means of infrared thermography at leaf and orchard scale." Functional Plant Biology 41, no. 12 (2014): 1207. http://dx.doi.org/10.1071/fp14021.
Анотація:
Pseudomonas syringae pv. actinidiae (Psa), the causal agent of bacterial canker of kiwifruit, has become a worldwide threat for the kiwifruit industry. In this work, the potential of infrared thermography for early detection of physiological symptoms related to Psa-infection at leaf and at orchard block scale was assessed. At the leaf level, thermal cold spots appeared shortly after Psa-infection, well before any visual symptoms. A few weeks after infection, thermal hot spots were observed, associated with, but not limited to, spots of visible leaf necrosis. At orchard block level, Psa-infected canes were significantly warmer in both blocks and on all measurement days. A novel wet reference surface, existing of a cluster of cotton imitation leaves with similar dimensions and orientation as real leaves and remaining wet through sucking up water from a small container, was used to estimate the crop water stress index (CWSI). CWSI showed stable values of infected and uninfected areas during the day and between following days. Crop temperature and CWSI were closely correlated with leaf stomatal conductance, which was lower in infected canes. A Psa-infection map based on canopy temperature revealed that Psa infects the outer canes rather than the central part of the canopy.
41
Wang, J. H., J. Messner, and H. Stetter. "An Experimental Investigation of Transpiration Cooling. Part I: Application of an Infrared Measurement Technique." International Journal of Rotating Machinery 9, no. 3 (2003): 153–61. http://dx.doi.org/10.1155/s1023621x03000149.
Анотація:
This study was an investigation into the application of the infrared thermal imaging technique (IRTIT) to evaluate transpiration cooling performance through a porous wall. Two typical infrared thermograph systems, the AGA 782 short-wavelength system and the VARIOSCAN 3021 long-wavelength system, were employed to demonstrate the availability of the IRTIT measurement. In comparison with general infrared apparent temperature measurement, several factors that influence measurement accuracy need to be addressed in the application of the IRTIT in the region of transpiration cooling on the porous surfaces of turbine components. In this article, the influence of these factors on measurement accuracy is discussed, the corresponding calibration methods of the two infrared systems are described, and the ambient conditions and stability of the measurement are analyzed. Aporous circular tube was used as a specimen. The tube consisted of sintered chromium-nickel steel with a porosity of 21%. The experiment was carried out in the hotgas wind tunnel at the Institute of Thermal Turbomachinery at the University of Stuttgart, Stuttgart, Germany.
42
Kafadarova, Nadezhda, Sotir Sotirov, Franz Herbst, Anna Stoynova, and Stefan Rizanov. "A System for Determining the Surface Temperature of Cylindrical Lithium-Ion Batteries Using a Thermal Imaging Camera." Batteries 9, no. 10 (October 22, 2023): 519. http://dx.doi.org/10.3390/batteries9100519.
Анотація:
The topic of battery state-of-health monitoring via electrical and non-electrical testing procedures has become of increased interest for scientific researchers, due to the imposed goal of expanded industrial sustainability. Within the present study, we propose a novel approach for monitoring the temperature of batteries by means of infrared thermography. In order to improve the accuracy of the performed measurements and to overcome the limitations imposed by the cylindrical housing of the batteries, we have developed a unique method for monitoring and capturing the temperature of the battery over the entire housing. An experimental system was built, through which the battery performs a rotational movement relative to its axis, with this rotation motion being synchronized with the frame rate of the thermal camera. The resulting thermographic images are processed using specifically developed software. This software enables the segmentation of certain sections of the battery’s surface from a defined spatial perspective. These selected segments are subsequently utilized to generate a three-dimensional representation of the battery’s surface temperature’s distribution. In this way, errors in the obtained results which are caused by the viewing angle are avoided. Additionally, we developed and presented a method for the increasing of the resolution of captured thermograms.
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Tuschl, Christoph, Beate Oswald-Tranta, and Sven Eck. "Inductive Thermography as Non-Destructive Testing for Railway Rails." Applied Sciences 11, no. 3 (January 22, 2021): 1003. http://dx.doi.org/10.3390/app11031003.
Анотація:
Inductive thermography is a non-destructive testing method, whereby the specimen is slightly heated with a short heating pulse (0.1–1 s) and the temperature change on the surface is recorded with an infrared (IR) camera. Eddy current is induced by means of high frequency (HF) magnetic field in the surface ‘skin’ of the specimen. Since surface cracks disturb the eddy current distribution and the heat diffusion, they become visible in the IR images. Head checks and squats are specific types of damage in railway rails related to rolling contact fatigue (RCF). Inductive thermography can be excellently used to detect head checks and squats on rails, and the method is also applicable for characterizing individual cracks as well as crack networks. Several rail pieces with head checks, with artificial electrical discharge-machining (EDM)-cuts and with a squat defect were inspected using inductive thermography. Aiming towards rail inspection of the track, 1 m long rail pieces were inspected in two different ways: first via a ‘stop-and-go’ technique, through which their subsequent images are merged together into a panorama image, and secondly via scanning during a continuous movement of the rail. The advantages and disadvantages of both methods are compared and analyzed. Special image processing tools were developed to automatically fully characterize the rail defects (average crack angle, distance between cracks and average crack length) in the recorded IR images. Additionally, finite element simulations were used to investigate the effect of the measurement setup and of the crack parameters, in order to optimize the experiments.
44
Li, Yanhui, Zhouyang Bai, Limei Xing, Qian Zhang, Shaoming Ding, Yinan Zhang, Pengfei Gao, Zhihong Yu, and Donghai Xu. "Corrosion Monitoring Techniques in Subcritical and Supercritical Water Environments." Applied Sciences 14, no. 6 (March 11, 2024): 2350. http://dx.doi.org/10.3390/app14062350.
Анотація:
A series of advanced equipment exposed to sub-/supercritical water environments at high temperatures, high pressures, and extreme water chemistry with high salt and dissolved oxygen content faces serious corrosion problems. Obtaining on-site corrosion data for typical materials in harsh environments is crucial for operating and maintaining related equipment and optimizing various corrosion prediction models. First, this article introduces the advantages and disadvantages, usage scenarios, and future development potential of several in situ monitoring technologies, including ultrasonic thickness measurement, the infrared thermography method, microwave imaging, eddy current detection, and acoustic emission. Considering the importance of electrochemical corrosion data in revealing microscale and nanoscale corrosion mechanisms, in situ testing techniques such as electrical resistance probes, electrochemical corrosion potential, electrochemical impedance spectroscopy, and electrochemical noise that can be applied to sub-/supercritical water systems were systematically discussed. The testing platform and typical data obtained were discussed with thick and heavy colors to establish a mechanical prediction model for corrosion behavior. It is of great significance to promote the development of corrosion monitoring techniques, such as breaking through testing temperature limitations and broadening the industrial application scenarios and maturity.
45
Türkgeldi, Burak, Fisun Koç, Maximilian Lackner, Berrin Okuyucu, Ersen Okur, Valiollah Palangi, and Selim Esen. "Infrared Thermography Assessment of Aerobic Stability of a Total Mixed Ration: An Innovative Approach to Evaluating Dairy Cow Feed." Animals 13, no. 13 (July 6, 2023): 2225. http://dx.doi.org/10.3390/ani13132225.
Анотація:
A major objective of this study is to identify factors influencing the quality of high-moisture total mixed rations (TMRs) for livestock feed and explore possible manipulations that can enhance their fermentation characteristics and stability in order to address the problem of poor aerobic stability. Therefore, the current study utilized infrared thermography (IRT) to assess the aerobic stability of water-added TMRs in the feed bunker. By manipulating the moisture content of freshly prepared TMRs at four different levels through water addition and subjecting it to storage at two consistent temperatures, significant correlations between IRT values (center temperature (CT) and maximum temperature difference (MTD)) and key parameters such as lactic acid bacteria, water-soluble carbohydrates, and TMR pH were established. The first and second principal components together accounted for 44.3% of the variation, with the first component’s load influenced by IRT parameters, fermentation characteristics, and air exposure times, while the second component’s load was influenced by dry matter content and lactic acid concentration. The results of these studies indicate the possibility that feeding methods can be optimized by identifying portions with higher CT or MTD data using IRT measurements just before feeding dairy cows in the field. As a result, increasing the use of IRT in feed management and preservation processes is projected to have a positive impact on animal productivity in the future.
46
Negishi, Toshiaki, Shigeto Abe, Takemi Matsui, He Liu, Masaki Kurosawa, Tetsuo Kirimoto, and Guanghao Sun. "Contactless Vital Signs Measurement System Using RGB-Thermal Image Sensors and Its Clinical Screening Test on Patients with Seasonal Influenza." Sensors 20, no. 8 (April 13, 2020): 2171. http://dx.doi.org/10.3390/s20082171.
Анотація:
Background: In the last two decades, infrared thermography (IRT) has been applied in quarantine stations for the screening of patients with suspected infectious disease. However, the fever-based screening procedure employing IRT suffers from low sensitivity, because monitoring body temperature alone is insufficient for detecting infected patients. To overcome the drawbacks of fever-based screening, this study aims to develop and evaluate a multiple vital sign (i.e., body temperature, heart rate and respiration rate) measurement system using RGB-thermal image sensors. Methods: The RGB camera measures blood volume pulse (BVP) through variations in the light absorption from human facial areas. IRT is used to estimate the respiration rate by measuring the change in temperature near the nostrils or mouth accompanying respiration. To enable a stable and reliable system, the following image and signal processing methods were proposed and implemented: (1) an RGB-thermal image fusion approach to achieve highly reliable facial region-of-interest tracking, (2) a heart rate estimation method including a tapered window for reducing noise caused by the face tracker, reconstruction of a BVP signal with three RGB channels to optimize a linear function, thereby improving the signal-to-noise ratio and multiple signal classification (MUSIC) algorithm for estimating the pseudo-spectrum from limited time-domain BVP signals within 15 s and (3) a respiration rate estimation method implementing nasal or oral breathing signal selection based on signal quality index for stable measurement and MUSIC algorithm for rapid measurement. We tested the system on 22 healthy subjects and 28 patients with seasonal influenza, using the support vector machine (SVM) classification method. Results: The body temperature, heart rate and respiration rate measured in a non-contact manner were highly similarity to those measured via contact-type reference devices (i.e., thermometer, ECG and respiration belt), with Pearson correlation coefficients of 0.71, 0.87 and 0.87, respectively. Moreover, the optimized SVM model with three vital signs yielded sensitivity and specificity values of 85.7% and 90.1%, respectively. Conclusion: For contactless vital sign measurement, the system achieved a performance similar to that of the reference devices. The multiple vital sign-based screening achieved higher sensitivity than fever-based screening. Thus, this system represents a promising alternative for further quarantine procedures to prevent the spread of infectious diseases.
47
Alvarado-Cruz, Laura Benita, Carina Toxqui-Quitl, Raúl Castro-Ortega, Alfonso Padilla-Vivanco, and José Humberto Arroyo-Núñez. "Highly Discriminative Physiological Parameters for Thermal Pattern Classification." Sensors 21, no. 22 (November 21, 2021): 7751. http://dx.doi.org/10.3390/s21227751.
Анотація:
Infrared Thermography (IRT) is a non-contact, non-intrusive, and non-ionizing radiation tool used for detecting breast lesions. This paper analyzes the surface temperature distribution (STD) on an optimal Region of Interest (RoI) for extraction of suitable internal heat source parameters. The physiological parameters are estimated through the inverse solution of the bio-heat equation and the STD of suspicious areas related to the hottest spots of the RoI. To reach these values, the STD is analyzed by means: the Depth-Intensity-Radius (D-I-R) measurement model and the fitting method of Lorentz curve. A highly discriminative pattern vector composed of the extracted physiological parameters is proposed to classify normal and abnormal breast thermograms. A well-defined RoI is delimited at a radial distance, determined by the Support Vector Machines (SVM). Nevertheless, this distance is less than or equal to 1.8 cm due to the maximum temperature location close to the boundary image. The methodology is applied to 87 breast thermograms that belong to the Database for Mastology Research with Infrared Image (DMR-IR). This methodology does not apply any image enhancements or normalization of input data. At an optimal position, the three-dimensional scattergrams show a correct separation between normal and abnormal thermograms. In other cases, the feature vectors are highly correlated. According to our experimental results, the proposed pattern vector extracted at optimal position a=1.6 cm reaches the highest sensitivity, specificity, and accuracy. Even more, the proposed technique utilizes a reduced number of physiological parameters to obtain a Correct Rate Classification (CRC) of 100%. The precision assessment confirms the performance superiority of the proposed method compared with other techniques for the breast thermogram classification of the DMR-IR.
48
Elfarhani, Makram, Fethi Guesmi, Ali Mkaddem, Sami Ghazali, Saeed Rubaiee, and Abdessalem Jarraya. "Thermal Aspects in Edge Trimming of Bio-Filled GFRP: Influence of Fiber Orientation and Silica Sand Filler in Heat Generation." Materials 15, no. 14 (July 8, 2022): 4792. http://dx.doi.org/10.3390/ma15144792.
Анотація:
The present work aims to determine the influence of Glass Fiber-Reinforced Polymer (GFRP) laminating configuration in heat generation during the dry edge trimming process. Temperature measurement experiments were conducted on pure epoxy matrix, 15% unidirectional glass fiber reinforced epoxy, and 28% silica sand-filled GFRP specimens through eight type-K thermocouples evenly distributed along the trim plans and connected to a data acquisition system. Infrared thermographic measurements were also conducted to investigate the tool temperature evolution while processing. It was found that perpendicular fiber edge milling induces a sharp increase with peak temperature measurements reaching 119 °C, while machining parallel to fiber leads to a maximum temperature history of 41 °C, which is very close to that obtained from the pure epoxy test. It was also found that the addition of silica sand grains in the GFRP matrix reduces both tool and specimen temperature magnitudes up to 67% for 90° plies and 14% for 0° plies compared to silica sand-free composite initial values. The heat partition was calculated from the measured (electric) and estimated energies for the tool, the workpiece, and chips, respectively. It appears from predictions that the addition of silica sand grains increases the heat conductivity of the GFRP materials (with rates of 20% for 0° fiber orientation and 10% for 90° fiber direction), while it reduces that conducted to the milling tool. Scanning Electron Microscopy (SEM) inspections helped detect the dominating machining defects relative to each GFRP configuration and explained the heat generation and dissipation effects in light of peak temperature measurements.
49
Lazzi Gazzini, Sebastiano, Rainer Schädler, Anestis I. Kalfas, Reza S. Abhari, Sebastian Hohenstein, Gregor Schmid, and Ewald Lutum. "Effect of purge air on rotor endwall heat transfer of an axial turbine." Journal of the Global Power and Propulsion Society 1 (October 12, 2017): F29ZWY. http://dx.doi.org/10.22261/f29zwy.
Анотація:
AbstractIn order to gain in cycle efficiency, turbine inlet temperatures tend to rise, posing the challenge for designers to cool components more effectively. Purge flow injection through the rim seal is regularly used in gas turbines to limit the ingestion of hot air in the cavities and prevent overheating of the disks and shaft bearings. The interaction of the purge air with the main flow and the static pressure field of the blade rows results in a non-homogenous distribution of coolant on the passage endwall which poses questions on its effect on endwall heat transfer. A novel measurement technique based on infrared thermography has been applied in the rotating axial turbine research facility LISA of the Laboratory for Energy Conversion (LEC) of ETH Zürich. A 1.5 stage configuration with fully three-dimensional airfoils and endwall contouring is integrated in the facility. The effect of different purge air mass flow rates on the distribution of the heat transfer quantities has been observed for the rated operating condition of the turbine. Two-dimensional distributions of Nusselt number and adiabatic wall temperature show that the purge flow affects local heat loads. It does so by acting on the adiabatic wall temperature on the suction side of the passage until 30% of the axial extent of the rotor endwall. This suggests the possibility of effectively employing purge air also as rotor platform coolant in this specific region. The strengthening of the secondary flows due to purge air injection is observed, but plays a negligible role in varying local heat fluxes. For one test case, experimental data is compared to high-fidelity, unsteady Reynolds-Averaged Navier–Stokes simulations performed on a model of the full 1.5 stage configuration.
50
Zhang, Huibo, Ya Chen, Hiroshi Yoshino, Jingchao Xie, Zhendong Mao, Jingwen Rui, and Jinfeng Zhang. "Winter Thermal Environment and Thermal Performance of Rural Elderly Housing in Severe Cold Regions of China." Sustainability 12, no. 11 (June 3, 2020): 4543. http://dx.doi.org/10.3390/su12114543.
Анотація:
Understanding the thermal performance of the residential envelope is important for optimizing the indoor thermal environment. In this study, the indoor thermal environment and thermal performance of rural residences housing the elderly was determined through field measurements in Qiqihar in 2017 and 2019. The results revealed that the living room temperatures in more than 50% of homes were below the thermal neutral temperature for the elderly (17.32 °C). Moreover, the indoor thermal environment changed significantly during the day, with the predicted mean vote during the day fluctuating from 2 to 4 units. The air change rate of living rooms in 2017 and 2019 was 0.20–2.20 h−1 and 0.15–1.74 h−1, respectively. Residential ventilation times detected by an air-tightness detector ranged from 0.40–1.49 h−1. Furthermore, infrared thermography (IRT) detected air leakage in the windows of the all houses in this study, as well as thermal bridges and condensation on the exterior walls of several houses. The heat transfer coefficient of the exterior walls of all houses detected by IRT was 0.25–0.74 W/(m2·K), and a significant positive correlation was observed between the heat transfer coefficient of the south wall and the window-to-wall ratio. Finally, the heat transfer coefficient of the external walls exhibited a negative but not significant correlation with indoor temperature. This study provides detailed data and guidance for improving the indoor environment of rural houses in severe cold regions.