Search

The present work reports the thermal behavior of synthetic jets (SJs) with different non-circular orifices and various waveforms such as triangular, sinusoidal, and square. Tests are conducted for the different nozzle-to-plate spacing (1–25) for a given value of Reynolds number (5380). The triangular waveform exhibits better heat transfer for all the orifice shapes. The value of maximum heat transfer for rectangular SJ is found to be 32% and 16.5% higher than isosceles and equilateral triangular SJs, respectively. The equilateral triangular SJ exhibits 12.9% higher heat transfer than the isosceles triangular SJ. The power spectral density distribution is plotted for all three waveforms. [ABSTRACT FROM AUTHOR]

The effect of the metal foam thickness on the conduction and convection heat transfer for a metal foam flat plate impinged by a circular air jet is investigated. The IR thermography and thin-metal foil technique are used for the measurement of local heat transfer. An open-cell aluminum metal foam is used for the metal foam flat plate. A 3D-printed resin foam and detached metal foam flat plate are used for the appreciation of the conduction and convection heat transfer. The varying parameters are the thickness of the foam, Reynolds number, and the nozzle exit to plate distance. The presence of the metal foam offers a conduction effect. This predominates over the attenuation in the convective heat transfer by foam due to additional hydraulic resistance. The additional hydraulic resistance offered by the porous foam increases with the increase in the foam thickness. The heat transfer of a porous foamed flat plate decreases with the increase in the foam thickness. The local Nusselt number of the resin foam and detached foam flat plate is almost the same. The conduction effect and attenuation in the convection heat transfer of a metal foam flat plate are quantified by attenuation and enhancement factors. The overall augmentation offered by 4, 8, and 12 mm thick metal foam flat plates is 1.71, 1.42, and 1.43 times compared to the smooth flat plate case, respectively. Hence, it is advisable to use a metal foam flat plate with 4-mm-thick metal foam under circular air jet impingement. [ABSTRACT FROM AUTHOR]

Recently, the dairy sector has been ever more affected by global warming. This study aimed to test a novel conductive cooling system for cattle that was successfully implemented and evaluated under summer thermally challenging weather conditions in Poland. The system consists mainly of the chiller, tank, and chilled water-driven mattress, designed to prioritize animal well-being. The experimental evaluation was carried out on three Friesian dry cows, housed on different types of bedding—commercial water mattress, straw, and cooling water mattress—and supplied with water at 10 °C (day) and 16 °C (night). The cooling water mattress' surface temperature was twice as low as that of the commercial water mattress. The animal's thermal comfort was assessed with physiological and behavioral reactions. The cooling effect on animals' bodies was demonstrated with a lower reticulorumen temperature of the cooled cow (p < 0.05) than the reference ones. The local effect of cooling was proved with an 8 °C-lower skin temperature after the cow's resting period. The presented study opens a new research direction toward dairy cattle's welfare, sustainability, and the food–energy–water nexus, based on potential energy and water savings. [ABSTRACT FROM AUTHOR]

To counteract the adverse effects of mineral oil-based cutting fluids, manufacturing industries are aspire toward environment-friendly and less toxic cutting fluids. The biodegradability and non-toxic characteristics of vegetable oils make them an appropriate alternative to mineral oil-based cutting fluids. In this context, this research article presents the results of an experimental investigation carried out to improve the machining performance of AISI-1040 steel by utilizing coconut oil (CO) as a cutting fluid with minimum quantity lubrication and cooling (MQL) technique. A detailed investigation and analysis of tool flank wear, crater wear, cutting tool vibration, surface topography, cutting zone temperature, and chip morphology were performed under dry, flood, mineral oil with MQL (MQL-MO), and coconut oil with MQL (MQL-CO) cutting conditions. The findings of this investigation revealed that the MQL-CO is highly efficient in minimizing friction and heat dissipation. The tool wear was reduced by 52-58%, 33-37%, and 14-17% under MQL-CO as compared to dry, flood, and MQL-MO cutting conditions. In addition, the surface roughness values were reduced by 48%, 24%, and 22% and the cutting temperature was reduced by 40%, 22%, and 13% under MQL-CO than that of dry, flood, and MQL-MO cutting conditions. The MQL-CO cutting condition showed a considerable reduction in cutting tool vibration acceleration levels and a favorable chip morphology which improved the machining performance. [ABSTRACT FROM AUTHOR]

An infrared camera is the best tool for identifying the temperatures in various parts of thermal power plants. In this paper, authors identified the probable faults in different parts of the Boiler using temperature. A well-liked and secure technique to use in condition monitoring and preventative maintenance is infrared thermography. This procedure is directly applied to determine whether the machine is operating normally or not and also to identify the heat pattern that indicates inefficiency and flaws within the machine. For the asset manager, it is the best practice. This procedure lowers the danger and increases operational dependability. Checking bearings and belts, and keeping an eye on electrical rooms, panel boards, rotating motors, boiler operations, etc., are all made easier using infrared thermography. This method helps pinpoint the precise site of the equipment or machine malfunction. It can avoid events that can happen due to destruction from heat radiation and save energy, money, time, and money on repairs. If the operations are prepared for the obstacles, they can be managed successfully. This paper presents details of an Expert system for Boilers in Thermal power plants.

A new class of biologics is obtained using the technologically processed of antibodies (TPA), which are used as the initial substance, and their dilution at each stage is accompanied by a controlled external vibrational (mechanical) treatment. This article focuses on the development and validation of a novel technique that can be applied for assessing the identity of TPA-based drugs. It has previously been found that after such treatment, the resulting solution either acquired new properties that were not present in the initial substance or a quantitative change in properties compared to the initial substance was observed. The use of mechanical treatment during the manufacture of the TPA-based drugs can cause the formation of new bonds between the solvent and antibody molecules. These changes manifest themselves in altered adsorption at the surface of the test solutions, which results in the formation of a near-surface film. One of the indicators of such events is the change in the surface temperature of the solution, which can be analyzed using high-resolution thermography. Unlike other methods, the high-resolution thermography allows the near-surface layer of a heterogeneous aqueous solution to be clearly visualized and quantified. A number of experiments were performed: seven replicates of sample preparations were tested; the influence of factors "day" or "operator" was investigated during 12 days of testing by two operators. The method also allowed us to distinguish between technologically processed antibodies and samples containing technologically processed buffer. The thermographic analysis has proven to be a simple, specific, and reproducible technique that can be used to analyze the identity of TPA-based drugs, regardless of the dosage form tested. [ABSTRACT FROM AUTHOR]

This paper aims to study the effect of ultrasonic aluminum (Al) bonding and lamination processes on the electrical performance of copper indium gallium (di)selenide (CIGS) thin film photovoltaic (TFPV) solar panels. Ultrasonic Al bonding on the MoSe2 layer of the CIGS TFPV solar panel was performed in three configurations: eight bonds, 16 bonds, and parallel configurations. The lamination process was performed on the Al bonds with MoSe2 layers of the CIGS TFPV solar panel. Ultrasonic bonding and lamination processes significantly affect the electrical performance of CIGS TFPV solar panels. Open circuit voltage, Voc is the least affected electrical characteristic with the application of ultrasonic bonding and lamination processes as compared to short circuit current (Isc), current density (Jsc), maximum power (Pmpp), fill factor (FF), and efficiency. 8-bonds configuration has the highest efficiency, ranging from 11.45% to 13.86% throughout unique connections of I-V measurement, compared to 16-bonds ranging from 7.99% to 10.77%, and parallel configurations, ranging from 9.14% to 11.92%. The notable variations in electrical properties with the processes used to create laminated CIGS TPFV solar panels with ultrasonic Al bonding can be explained by physical examination and lock-in infrared (IR) thermography. The ultrasonic Al bond is best suited to be used as the interconnection mean in the CIGS TFPV solar panel compared to that of conductive adhesive that has been widely applied nowadays. [ABSTRACT FROM AUTHOR]

The Heat Flux Engineering Analysis Toolkit (HEAT) (Looby et al., 2022) was used to simulate the heat flux, qtarget, on ST40 molybdenum divertors. Results were compared with experimental infrared (IR) data. Two shots, 11419 and 11376 at time instants 119 ms and 120 ms, with lower-biased disconnected double null geometries, were studied. Single-λ and multi-λ heat flux profiles were used as input in HEAT simulation. The simulated qtarget was used in OpenFOAM to calculate the corresponding temperature, T, on the divertors. Results showed that a good agreement on the simulated qtarget, T and shape of the heat flux on the divertor with the IR data was achieved when a multi-λ heat flux profile was used for 11419, and single-λ heat flux profile for 11376. This indicates that HEAT can be reliable in analyzing and understanding the heat loading of plasma facing components in tokamak devices.

Abstract Knowledge of salt and moisture distribution is a key factor for understanding rock decay at cultural heritage sites. The cave town of Uplistsikhe in Georgia, carved from sandstone in late bronze age to medieval times, suffers from progressive scaling and flaking processes. Multi-method investigations of rock moisture and salt distribution were carried out in order to better understand the patterns of decay. Salt distribution was investigated using drill dust samples and paper pulp poultices; moisture was determined by 2D-resistivity and handheld microwave sensors, supplemented by infrared thermography. The combined results from the different methods revealed a complex pattern of salt and moisture distribution. At most sites, K2SO4 (arcanite) and its hydrates dominate, sometimes in combination with CaSO4 (gypsum). At one site (Grandhall), halite (NaCl) and niter (KNO3) prevail. Sulphates are assumed to be a legacy of air pollution; origin of halite and niter remains unsolved but might be due to concrete reinforcements. Two main sources of moisture were evidenced depending on season and spatial situation: (1) Condensation of air humidity at cool cave backwalls in spring (combined with and aided by salt hygroscopicity), evidenced by 2D-resistivity and infrared thermography; (2) seepage along joints particularly at the cave backwalls and roofs, evidenced by handheld microwave sensors. Further investigations should focus on identifying seepage pathways and on clarifying the origin of destructive halite and nitrates.

Knowledge of salt and moisture distribution is a key factor for understanding rock decay at cultural heritage sites. The cave town of Uplistsikhe in Georgia, carved from sandstone in late bronze age to medieval times, suffers from progressive scaling and flaking processes. Multi-method investigations of rock moisture and salt distribution were carried out in order to better understand the patterns of decay. Salt distribution was investigated using drill dust samples and paper pulp poultices; moisture was determined by 2D-resistivity and handheld microwave sensors, supplemented by infrared thermography. The combined results from the different methods revealed a complex pattern of salt and moisture distribution. At most sites, K2SO4 (arcanite) and its hydrates dominate, sometimes in combination with CaSO4 (gypsum). At one site (Grandhall), halite (NaCl) and niter (KNO3) prevail. Sulphates are assumed to be a legacy of air pollution; origin of halite and niter remains unsolved but might be due to concrete reinforcements. Two main sources of moisture were evidenced depending on season and spatial situation: (1) Condensation of air humidity at cool cave backwalls in spring (combined with and aided by salt hygroscopicity), evidenced by 2D-resistivity and infrared thermography; (2) seepage along joints particularly at the cave backwalls and roofs, evidenced by handheld microwave sensors. Further investigations should focus on identifying seepage pathways and on clarifying the origin of destructive halite and nitrates. [ABSTRACT FROM AUTHOR]

This paper focuses on an integrated approach to study the materials and the degradation issues in the urban mural painting Ama Il Tuo Sogno, painted by the famous street artist Jorit Agoch in Matera (Italy). The study was conducted in the framework of a conservation project, aiming to contrast a progressive decay affecting the artifact that started a few months after its creation. Multi-analytical techniques were used to investigate the stratigraphy and chemical composition of the pictorial film within a low-impact analytical protocol for sustainable diagnostics. They included polarized light microscopy in UV and VIS reflected light, FTIR spectroscopy, Py-GC-HRAMS, and SEM-EDS. The mineralogical–petrographic composition of the mortar employed in the pictorial support was also studied with optical microscopy of thin sections and X-ray diffractometry. To know the mechanism underlying the degradation, IR thermography was performed in situ to establish the waterways and the distribution of the humidity in the mural painting. In addition, ion chromatography and X-ray diffractometry were used to identify and quantify the soluble salts and to understand their sources. The overall results allowed us to determine the chemical composition of the binder and pigments within the pictorial layers, the mineralogical–petrographic characteristics of the mortar of the support, and the execution technique of the painting. They also highlighted a correlation between the presence of humidity in the painted mural and the salt damage. The mineralogical phases were detected in the mural materials by XRD, and the results of ion chromatographic analyses suggested a supply of soluble salts mainly from the mortar of the support. Finally, the study provided basic knowledge for planning appropriate sustainable conservation measures. [ABSTRACT FROM AUTHOR]

Options for implementing the IR thermography diagnostic system in a TRT facility are considered. Two variants of the optical scheme for measuring the temperature of the first wall and divertor targets are proposed: a wide-angle system combined with two divertor channels and a four-channel viewing system. The optical resolution of both systems and the levels of the collected signal are numerically simulated. On the basis of the calculations performed, conclusions are drawn about the compliance of the systems with the requirements for measuring the temperature of TRT plasma-facing elements. The sources of the temperature measurement error are considered, and the error caused by the reflection of radiation from structural plasma-facing elements by the surface under study is estimated. Calibration issues for IR thermography diagnostics are also discussed. [ABSTRACT FROM AUTHOR]

Recently, the dairy sector has been ever more affected by global warming. This study aimed to test a novel conductive cooling system for cattle that was successfully implemented and evaluated under summer thermally challenging weather conditions in Poland. The system consists mainly of the chiller, tank, and chilled water-driven mattress, designed to prioritize animal well-being. The experimental evaluation was carried out on three Friesian dry cows, housed on different types of bedding—commercial water mattress, straw, and cooling water mattress—and supplied with water at 10 °C (day) and 16 °C (night). The cooling water mattress’ surface temperature was twice as low as that of the commercial water mattress. The animal’s thermal comfort was assessed with physiological and behavioral reactions. The cooling effect on animals’ bodies was demonstrated with a lower reticulorumen temperature of the cooled cow (p < 0.05) than the reference ones. The local effect of cooling was proved with an 8 °C-lower skin temperature after the cow’s resting period. The presented study opens a new research direction toward dairy cattle’s welfare, sustainability, and the food–energy–water nexus, based on potential energy and water savings.

This paper presents a simple engineering method for evaluating the optical power emitted by light-emitting diodes (LEDs) using infrared thermography. The method is based on the simultaneous measurement of the electrical power and temperature of an LED and a heat source (resistor) that are enclosed in the same plastic packaging under the same cooling conditions. This ensures the calculation of the optical power emitted by the LED regardless of the value of the heat transfer coefficient. The obtained result was confirmed by comparing it with the standard direct measurement method using an integrated sphere. The values of the estimated optical power using the proposed method and the integrated sphere equipped with a spectrometer were consistent with each other. The tested LED exhibited a high optical energy efficiency, reaching approximately η ≈ 30%. In addition, an uncertainty analysis of the obtained results was performed. Compact modelling based on a thermal resistor network (Rth) and a 3D-FEM analysis were performed to confirm the experimental results. [ABSTRACT FROM AUTHOR]

• Integrated approach for multi-scale and multi-resolution diagnostics of wall paintings by the combination of wave-based and optical techniques. • Surface and subsurface investigation for the stratigraphic reconstruction of past intervention and modification. • For the first time, the microwave reflectometry is here proposed in combination with digital holographic speckle pattern interferometry for wall paintings inspection. • Proof of concept of the proposed tool on the wall paintings masterpiece of Masolino, Masaccio and Filippino Lippi in the Brancacci chapel in Firenze. Based on the analysis of the renaissance wall paintings by Masaccio, Masolino, and Filippino Lippi in the Brancacci chapel in Firenze, this paper discusses the use of complementary non-destructive techniques based on microwave and optical methods for the characterization of the structural integrity of the wall paintings and their support in masonry. The selected non-destructive techniques are the InfraRed Thermography (IRT), Ground Penetrating Radar (GPR), Microwave Reflectometry (MWR), and Digital Holographic Speckle Pattern Interferometry (DHSPI). In particular, the paper analyses the in-situ applicability of these techniques for the identification of the sequence of past interventions during centuries (stratigraphy analysis) and decay phenomena and defects, such as out-of-plumb or swelling area/elements, detachments, cracks and voids inside the wall. The results are compared with data obtained by means of consolidated techniques and methods, such as the Photogrammetry (performed by Structure from Motion method) and knocking test. The last one is normally used by restorers and conservators to recognize the presence of detachments. The proposed diagnostic strategy provides a survey from large scale by means of imaging techniques, to small scale increasing the spatial resolution thanks to the scanning of the surface by means of spot techniques. Therefore, the macroscopic survey of wall paintings was carried out using photogrammetry, in order to also provide metric information, to quantify the sizing out-of-plumb and swelling of the masonry or to locate of cracks, and followed by IRT. This preliminary morphometric survey was, supplemented by GPR, MWR and DHSPI for improve the results of the investigation. By combining these three techniques it was possible to inspect the entire thickness of the masonry (60-70 cm) with resolutions ranging from a few millimetres up to several centimetres. The combination of microwave-based and optical-based methods proved to be a valuable addition to routine methods for the holistic masonry diagnosis. Standard practice based on visual inspection and knocking test can be significantly improved and objectified by the proposed full-field, multi-sensor, multi-resolution approach. [ABSTRACT FROM AUTHOR]

The present experimental study reports the flow and heat transfer characteristics of a synthetic jet issuing from a sharp-edged orifice (diverging-shaped orifice). The experiments are carried out for a varied range of opening angles of sharp-edged orifices (θ = 0°, 30°, 60°, 90°, and 120°), Reynolds number (Re = 3243–8143), different jet-to-surface spacings (z/d = 1–16), and for two different values of orifice thicknesses, t = 5 mm (t/d = 0.33) and 10 mm (t/d = 0.66). The hot-wire anemometry is used to study the flow characteristics of synthetic jet, while heat transfer characteristics are studied by using a thermal imaging technique. The time-averaged flow fields associated with sharp-edged orifices reveal that orifices with t = 5 mm and 10 mm exhibit saddle-backed and top-hat velocity profile shapes, respectively. The results show that for a square-edge orifice (θ = 0°), the heat transfer rate decreases with an increase in orifice plate thickness from 5 to 10 mm, while the opposite trend in heat transfer is observed with sharp-edged orifice. The heat transfer rate with a 10 mm thick sharp-edged orifice is higher than the 5 mm thick sharp-edged orifice for all the tested opening angles. Furthermore, the results also show that for sharp-edged orifices, the heat transfer rate increases with the increase in opening angle from θ = 0° to 60°, while it decreases with further increasing from θ = 60° to 120°. The maximum value of average Nusselt number (Nuavg) is obtained for θ = 60° for both the orifice thicknesses (t = 5 and 10 mm), and this effect is found to be more pronounced for t = 10 mm orifice. For sharp-edged orifice (θ = 60°), the maximum enhancement in Nuavg is found to be 12.66% and 23% higher for t = 5 mm and 10 mm, respectively, compared to the equivalent square-edged orifice (θ = 0°). The cause for variation in heat transfer rate with sharp-edged orifices is interpreted due to the effect of flow recirculation and mass flow rate. A correlation has been proposed for Nuavg as a function of different opening angles. The present finding is useful for the optimization of the synthetic jet geometrical parameters for the effective heat transfer rate. [ABSTRACT FROM AUTHOR]

In this study, silver nanoparticles (AgNPs) were prepared using a green synthesis method. The optical and structural properties of these AgNPs were studied with UV-vis spectroscopy, X-ray diffraction, FE-SEM and TEM. In the UV-vis absorption spectrum, the highest peak appeared at 400 nm. The AgNPs produced had a nanocrystalline cubic structure with a crystallite size of (9.25-18.61) nm, according to the X-ray pattern. The FESEM data demonstrated that the synthesised AgNPs combine. AgNPs examined by TEM at different magnifications revealed that most particles were spherical and evenly scattered. According to the TEM histogram, the particles were highly monodispersed AgNPs with an average diameter of 45 nm. An infrared thermal imaging technique (IRT) was used to clarify the change in temperature when the AgNPs affected the skin. The material was placed on the skin in two ways and on the feet of rabbits. When the AgNPs were mixed with distilled water, a decrease in temperature was noticed, likely due to the role of water in cooling the skin. When the AgNPs were mixed with commercial Vaseline, a slight increase in the skin temperature was observed. The radiance related to the change of temperature in two bands (3-5 and 8-14 μm) was calculated. The highest value in the range 3-5 μm was 0.8730 at the maximum temperature of 32.1 °C while the highest value of the 8-14 μm band was 0.5621 at a maximum temperature of 37.1 °C. The total spectral radioactive emission is proportional to the area under the curves and shifts towards shorter wavelengths with increasing temperature. By comparing data from line profiles from different temperatures, radial heat diffusion is observed, causing energy to be transmitted to the surrounding regions from the immersed nanoparticles. [ABSTRACT FROM AUTHOR]

A new class of biologics is obtained using the technologically processed of antibodies (TPA), which are used as the initial substance, and their dilution at each stage is accompanied by a controlled external vibrational (mechanical) treatment. This article focuses on the development and validation of a novel technique that can be applied for assessing the identity of TPA-based drugs. It has previously been found that after such treatment, the resulting solution either acquired new properties that were not present in the initial substance or a quantitative change in properties compared to the initial substance was observed. The use of mechanical treatment during the manufacture of the TPA-based drugs can cause the formation of new bonds between the solvent and antibody molecules. These changes manifest themselves in altered adsorption at the surface of the test solutions, which results in the formation of a near-surface film. One of the indicators of such events is the change in the surface temperature of the solution, which can be analyzed using high-resolution thermography. Unlike other methods, the high-resolution thermography allows the near-surface layer of a heterogeneous aqueous solution to be clearly visualized and quantified. A number of experiments were performed: seven replicates of sample preparations were tested; the influence of factors “day” or “operator” was investigated during 12 days of testing by two operators. The method also allowed us to distinguish between technologically processed antibodies and samples containing technologically processed buffer. The thermographic analysis has proven to be a simple, specific, and reproducible technique that can be used to analyze the identity of TPA-based drugs, regardless of the dosage form tested.

The primary objective of this research is to address the research gap in the conservation of heritage buildings in Canada by integrating Historical Building Information Modeling (HBIM) as a tool. The proposed study aims to develop an enhanced framework for the preservation of historical buildings through the utilization of HBIM and 3D-scanning technology. As a result, the research aims to generate a comprehensive database comprising various families of models while also incorporating strategies for point-cloud clustering data. The significance of this research lies in its potential to contribute to the conservation and restoration process of historical buildings. Currently, there are a lack of standardized approaches and comprehensive databases for accurately documenting and reproducing historical buildings. By integrating HBIM and 3D-scanning technology, this research will enable the creation of highly accurate three-dimensional virtual models, consisting of millions of points, which will serve as a comprehensive dataset for the restoration of heritage buildings. The findings of this research will benefit multiple stakeholders. Preservation architects, conservationists, and heritage professionals will gain a valuable tool for documenting and analyzing historical buildings with a high level of precision. The comprehensive database and framework proposed in this study will facilitate decision-making processes during the restoration and preservation phases, ensuring that the original architectural elements and materials are faithfully reproduced. Additionally, policymakers and governmental organizations involved in heritage conservation can use the outcomes of this research to establish standardized guidelines and regulations for the preservation of historical buildings in Canada. Ultimately, the broader community will benefit from the enhanced preservation efforts, as it will contribute to the cultural and historical identity of the nation, fostering a sense of pride and connection to the past.

The contact sponge method is applied on a piece of clay brick. According to the standard, the sponge is moistened with water, applied on the surface of the material by means of a cup, and weighted before and after the application. It allows us to determine the amount of water absorbed by the porous material by unit area and unit time. After the application, the moistened area begins to evaporate and cool down. The IR camera is used to monitor the temperature variation of the imprint of the sponge. Meanwhile, moisture diffuses on the material as well. The IR camera is used to monitor the in-plane diffusion of moisture by following the imprint of the sponge that enlarges with time. A suitable model is used to evaluate the shape of the imprint that varies with time. [ABSTRACT FROM AUTHOR]

One of the main sources of damage to historical buildings is the presence of humidity. It is fundamental to develop a diagnosis protocol to identify the presence of water, evaluate the damage in a building (the whole structure, part of it or individual materials), assess its vulnerability and, finally, carry out a restoration plan. IR thermography is a sustainable method to guarantee structure analysis and preservation. Here, an application is presented, permitting us to identify the wet and dry areas and transition zone related to evaporation on the surface of the investigated materials. Thanks to temperature maps, it is possible to observe saturated regions, qualitatively at first and then quantitatively, processing the images by plotting reference lines/points and correlating surface temperatures with moisture. [ABSTRACT FROM AUTHOR]

Processes of the formation of wind waves remain poorly understood, despite numerous studies. One of the main reasons, in our opinion, is that simplified theoretical analysis does not take into account the weak film of natural contaminants. In the present work, wave generation in two channels is experimentally studied and compared for ethanol, water, and water with the addition of a soluble surfactant (sodium dodecyl sulphate (SDS)) in various concentrations. These concentrations hardly affect the surface tension coefficient, but they lead to a significant modification of the subsurface flow structure. In ethanol, the surface film is not formed, so it can be considered a reference case. In water and water with the surfactant, the film is broken and the surface becomes pure at certain critical wind speed, which grows for increasing surfactant concentration. For the surface to remain pure, the contaminant adsorption to the surface must be compensated by its removal by the tangential stress. Three experimental techniques are used to study the influence of cool skin on the formation of the wind waves. The surface relief is measured with modified color schlieren technique and the liquid velocity fields are determined with particle image velocimetry (PIV). The surface temperature fields, which allow the identification of the regions of the rupture of cool skin, are obtained with IR thermography. IR thermography is also used to study the surface velocity field (IR PIV). The film is shown to have significant influence on both the wave amplitude and the structure of subsurface flow. [ABSTRACT FROM AUTHOR]

Assessing the performance of the ITER design for the tungsten (W) divertor Plasma Facing Units (PFUs) in a tokamak environment is a high priority issue to ensure efficient plasma operation. This paper reviews the most recent results derived from experiments and post-mortem analysis of the ITER-grade PFUs exposed in the WEST tokamak and the associated modelling, with a focus on understanding heat loading and damage evolution. Several shaping options, sharp or chamfered leading edge (LE), unshaped or shaped blocks with a toroidal bevel as foreseen in ITER, were investigated, under steady state heat fluxes of up to 120 MW⋅m−2 and 6 MW⋅m−2 on the sharp LE and top surface of the block, respectively. A very high spatial resolution (VHR) infrared (IR) camera (0.1 mm/pixel) was used to derive the temporal and surface distribution of the temperature and heat load on the castellated tungsten blocks for different geometric alignment and plasma conditions. Photonic modelling was required to reproduce the IR measurements in particular in the toroidal and poloidal gaps of the mono-block (MB) stacks where high apparent temperatures are observed. Specular reflection is found to be the dominant emitter in these parts of the blocks. W-cracking was observed on the leading edge of the blocks already within the first phase of plasma operation, during which the divertor was equipped with unshaped PFUs, including some intentionally misaligned blocks. Numerical analysis taking into account softening processes and mechanical stresses, revealed brittle failure due to transients as the dominant failure mechanisms. Ductile failure was observed in one particular block used for the melting experiment, therefore under extremely high steady state heat load conditions. W-melting achieved on actively cooled PFU exhibits specific features: shallow melting and slow melt displacement. Plasma exposure of pre-damaged PFUs at various damage levels (crack network and melted droplets) was carried out under high heat load conditions with several hours of cumulated plasma duration. IR data and preliminary surface analyses show no evidence of significant degradation damage progression under these conditions.

The primary objective of this research is to address the research gap in the conservation of heritage buildings in Canada by integrating Historical Building Information Modeling (HBIM) as a tool. The proposed study aims to develop an enhanced framework for the preservation of historical buildings through the utilization of HBIM and 3D-scanning technology. As a result, the research aims to generate a comprehensive database comprising various families of models while also incorporating strategies for point-cloud clustering data. The significance of this research lies in its potential to contribute to the conservation and restoration process of historical buildings. Currently, there are a lack of standardized approaches and comprehensive databases for accurately documenting and reproducing historical buildings. By integrating HBIM and 3D-scanning technology, this research will enable the creation of highly accurate three-dimensional virtual models, consisting of millions of points, which will serve as a comprehensive dataset for the restoration of heritage buildings. The findings of this research will benefit multiple stakeholders. Preservation architects, conservationists, and heritage professionals will gain a valuable tool for documenting and analyzing historical buildings with a high level of precision. The comprehensive database and framework proposed in this study will facilitate decision-making processes during the restoration and preservation phases, ensuring that the original architectural elements and materials are faithfully reproduced. Additionally, policymakers and governmental organizations involved in heritage conservation can use the outcomes of this research to establish standardized guidelines and regulations for the preservation of historical buildings in Canada. Ultimately, the broader community will benefit from the enhanced preservation efforts, as it will contribute to the cultural and historical identity of the nation, fostering a sense of pride and connection to the past. [ABSTRACT FROM AUTHOR]

The aim of the research is the infrared imaging technique IR Imaging was used to detect temperature changes and their effects on the skin.In this study, ZnO nanoparticles (ZnO NPs) were prepared by Green's synthesis method. This method is considered the safest, easiest, and cheapest way to manufacture nanomaterials. The optical and structural properties of ZnO NPs have been studied by various techniques such as UV visible, X-ray diffraction, Field emission scanning electron microscopy, and Transmission electron microscopy. ZnO NPs had a UV- visible absorption peak at around 300 nm. ZnO's average crystallite diameter was calculated to be 15.41 nm using Scherrer's equation, which was derived from the width at half maximum of the peak more intense on the 101 planes at 36.28°. The Field emission scanning electron microscopy data showed that the synthesized ZnO NPs have a consistent shape and size throughout their range, these NPs are characterized by their diameter and were assembled into cylindrical clusters of varying diameters, with an average size of 106. Different magnifications of the ZnO NPs examined by Transmission electron microscopy showed that the majority of the particles were homogeneously scattered. Infrared thermal imaging technique (IRT) is used to clarify the change in temperature with the effect of the substance on the skin. The material was placed on the skin in two ways and put on the rabbit's front and back feet. When mixing the powder material of ZnO NPs with distilled water, and mixing the powder material of ZnO NPs with commercial Vaseline, we notice in both cases a temperature rise. The radiance was calculated for each image related to the change of temperature in the band (3-5) µm. The highest value in the range (3-5) µm for image R2 with radiation was (0.9209). The total spectral radioactive emission is proportional to the area under the curves and shifts towards shorter wavelengths with increasing temperature.

This paper presents a simple engineering method for evaluating the optical power emitted by light-emitting diodes (LEDs) using infrared thermography. The method is based on the simultaneous measurement of the electrical power and temperature of an LED and a heat source (resistor) that are enclosed in the same plastic packaging under the same cooling conditions. This ensures the calculation of the optical power emitted by the LED regardless of the value of the heat transfer coefficient. The obtained result was confirmed by comparing it with the standard direct measurement method using an integrated sphere. The values of the estimated optical power using the proposed method and the integrated sphere equipped with a spectrometer were consistent with each other. The tested LED exhibited a high optical energy efficiency, reaching approximately η ≈ 30%. In addition, an uncertainty analysis of the obtained results was performed. Compact modelling based on a thermal resistor network (Rth) and a 3D-FEM analysis were performed to confirm the experimental results.

Introduction. Incipient fatigue damage in the metal superstructures of bridges creates certain threats to the safety of operation. Various methods of non-destructive testing are used for their timely detection and diagnosis. A modern and popular on-the-day solution is the method of infrared (IR) thermography. Due to the specifics of the operation of IR cameras, additional processing of recordings received from these cameras is required to obtain an accurate result. This work aims at presenting a method for processing thermofilms and describing the possibilities of its application under real conditions.Materials and Methods. A method for processing thermographic films was described. It provided detecting temperature anomalies using only information from the camera. The results of its application on the elements of existing metal bridge spans are presented.Results. It is shown that there are temperature anomalies for existing defects. This means that the defects continue to develop, which was confirmed by subsequent observations of their condition. In addition, a case of temperature anomaly in the defect-free external region was identified. This might be a sign of an incipient defect that could not be diagnosed by other methods. If the presence of this defect is confirmed during repeated examinations, it will be possible to diagnose hidden defects that have not yet come to the surface, and/or detect potentially collapsing places.Discussion and Conclusions. The IR thermography performance as a method of non-contact non-destructive testing is shown, as well as its operability on real objects under random load.

A synergistic set of NDT techniques, including I–V analysis, UVF imaging, IR thermography, and EL imaging, supports a diagnostics methodology developed in this work to qualitatively and quantitatively identify a wide range of PV defects. The methodology is based on (a) the deviation of the module electrical parameters at STC from their nominal values, for which a set of mathematical expressions was developed that provide an insight into potential defects and their quantitative impact on the module electrical parameters, and (b) the variation analysis of EL images captured at a sequence of bias voltages for a qualitative investigation on the spatial distribution and strength of the defects. The synergy of these two pillars, supported by UVF imaging, IR thermography, and I–V analysis cross-correlating their findings, makes the diagnostics methodology effective and reliable. It was applied on c-Si and pc-Si modules operating from 0–24 years, exhibiting a diversity of defects of varying severity, either pre-existing or formed by natural ageing or externally induced degradation. Defects such as EVA degradation, browning, corrosion in the busbar/interconnect ribbons, EVA/cell-interface delamination, pn-junction damage, e−+hole recombination regions, breaks, microcracks, finger interruptions, and passivation issues are detected. Degradation factors triggering a cascade of internal degradation processes through cause and effect are analysed and additional models are proposed for the temperature pattern under current mismatch and corrosion along the busbar, further empowering the cross-correlation of NDT results. Power degradation was determined from 1.2% in 2 years of operation to more than 50% in modules with film deposition. [ABSTRACT FROM AUTHOR]

Multilayer needle-punched nonwoven electric heating pads were developed, and their heating behavior was studied by changing the fiber type and needle punch density. Samples were tested by applying the power of 2.9 V over 10 cm2 of area for 10 s. IR thermography was used to investigate the electrical heating behavior. Thermographs revealed that heat spreads more significantly in wool samples as compared to cotton. For optimization, scoring of samples was done. Wool samples score is higher than that of cotton. The score increases by increasing the punch density of nonwoven. Heat retains more significantly in wool as compared to cotton. Heating behavior also changes by changing the punch density as by increasing the fiber entanglement heat holds more ominously within the structure. These attributes proposed that the needle-punched nonwoven heating pads are suitable for better electrical heating. [ABSTRACT FROM AUTHOR]

In this paper, we carried out a thermographic assessment of the hybrid PV/T system at four distinct times in the same day to analyze the behavior of the system and show the factors that can degrade the thermal and electrical performance of this cogeneration device. We utilized the 3D simulation of MATLAB software for temperature readings at each image. Too, the analysis of the heat distribution on the surface of the panel when the PV/T system was first dirty and then after cleaning. Additionally, over a number of days, the thermal and electrical yields of a PV/T system were assessed to ascertain the impact of environmental conditions on the system's overall output. The impact of uneven temperature distribution on thermal and electrical performance was demonstrated by this experiment. It is worth noting that the system's electrical efficiency rises with cooling, rising from 13.2% under natural conditions to 14.1% with cooling. When cooling is applied, thermal efficiency can reach 50%. Electrical power increases from 199.64 W in natural cooling to 215 W with forced cooling, an increase of around 7.5%. [ABSTRACT FROM AUTHOR]

The contact sponge method is applied on a piece of clay brick. According to the standard, the sponge is moistened with water, applied on the surface of the material by means of a cup, and weighted before and after the application. It allows us to determine the amount of water absorbed by the porous material by unit area and unit time. After the application, the moistened area begins to evaporate and cool down. The IR camera is used to monitor the temperature variation of the imprint of the sponge. Meanwhile, moisture diffuses on the material as well. The IR camera is used to monitor the in-plane diffusion of moisture by following the imprint of the sponge that enlarges with time. A suitable model is used to evaluate the shape of the imprint that varies with time.

One of the main sources of damage to historical buildings is the presence of humidity. It is fundamental to develop a diagnosis protocol to identify the presence of water, evaluate the damage in a building (the whole structure, part of it or individual materials), assess its vulnerability and, finally, carry out a restoration plan. IR thermography is a sustainable method to guarantee structure analysis and preservation. Here, an application is presented, permitting us to identify the wet and dry areas and transition zone related to evaporation on the surface of the investigated materials. Thanks to temperature maps, it is possible to observe saturated regions, qualitatively at first and then quantitatively, processing the images by plotting reference lines/points and correlating surface temperatures with moisture.

The consequences of tungsten (W) cracking on divertor lifetime and plasma operation are high priority issues for ITER. One actively cooled ITER-like plasma facing unit (PFU) has been pre-damaged in a High Heat Flux (HHF) facility before its installation in WEST in order to assess the damage evolution after tokamak plasma exposure. The resulting pre-damage exhibits micrometer-size crack network and high roughness on the tungsten monoblock (MB) top surface. A total of 10 MBs, equally distributed on the low and high field sides of the lower divertor, have been pre-damaged among the 35 radially aligned MBs characteristic of the WEST PFU. Subsequent plasma exposure was carried out, from the first breakdown achieved in WEST (in 2017) until the removal of the damaged PFU three years later (2020). On top of the whole WEST plasma exposure (covering C1-C4 experimental campaigns), a dedicated experiment has also been performed in the frame of the EU work program to maximize the power and energy loads on one of the damaged MBs featuring a “crack network” pattern. The MB top surface, including both “crack network” damage and “healthy” (undamaged) areas, was monitored with a high spatial resolution IR camera to detect any potential evolution of the damage pulse after pulse. This paper describes the full plasma exposure achieved in the WEST tokamak (including large number of steady-state and transient heat loading cycles), the dedicated “damaged PFU exposure” experiment together with the experimental results (heat loading on the damaged MBs). Post-mortem measurement reveals significant broadening of the cracks and new cracks in the electron beam loaded area only.

In this paper, the heat generated during deformation under the static testing of high-manganese TWIP steel with addition of niobium was determined. The research combined the interaction of heat generated during deformation, mechanical properties, hardness and microstructure. Temperature and strain were measured simultaneously using infrared (IR) thermography and digital image correlation (DIC) method. The average temperature measured at the necked region equals 42°C at the strain rate of 0.001 s−1 and exceeds 100°C at 0.5 s−1. Therefore at large strains, a reduction in stress was observed. The course of the hardness change coincides very well with the strain changes, however, at the strain rate of 0.5 s−1 near to the necking area the hardness equals to 360 HV2, whereas at the lower strain rates it equals to 370 HV2. These changes are connected mainly with increase in temperature to >100°C [ABSTRACT FROM AUTHOR]

Non-destructive evaluation (NDE) techniques are integral across diverse applications for void detection within composites. Infrared (IR) thermography (IRT) is a prevalent NDE technique that utilizes reverse heat transfer principles to infer defect characteristics by analyzing temperature distribution. Although the forward heat transfer problem is well-posed, its inverse counterpart lacks uniqueness, posing non-unique solutions. The present study performs simulations using finite element analysis (FEA) in defective (a penny-shaped defect) composites through which the heat transfer flux is modeled. A total of 2100 simulations with various defect positions and sizes (depth, size, and thickness) are executed, and the corresponding surface temperature vs. time and vs. distance diagrams are extracted. The FEA outputs provide ample input data for developing an explainable artificial intelligence (XAI) model to estimate the defect characteristics. A detailed feature engineering task is performed to select the representative information from the diagrams. Explainable decision tree-based machine learning (ML) models with transparent decision paths based on derived features are developed to predict the defect depth, size, and thickness. The ML models' results suggest superb accuracy (R 2 = 0.92 to 0.99) across all three defect characteristics. The provided workflow sets a benchmark applicable to a range of fields, including health monitoring. [Display omitted] [ABSTRACT FROM AUTHOR]

• To measure detailed local heat transfer on inner wall of supersonic nozzle, a half-nozzle with a sonic injection has been introduced. • Infrared thermography was utilized to measure heat transfer, and the understanding of heat transfer characteristics was further enhanced through the use of oil-flow visualization and measurement using pressure sensitive paint. • In a half nozzle, detailed local heat transfer induced by jet-crossflow interaction was analyzed for three different momentum flux ratio (J =0.5, 1.0 and 1.5). • The result of heat transfer measurement in the nozzle were compared with those obtained from our previous work on flat plates, and notable differences in heat transfer characteristics are observed. • For the efficient thermal design of a system, different strategy could be required for the nozzle and flat geometry. For example, deciding the type and thickness of composite materials or the localized application of titanium or abrasives around the injection hole. Heat transfer measurements were conducted to investigate surface heat transfer characteristics resulting from the interaction between a sonic jet and supersonic nozzle crossflow. A sonic jet was injected into the nozzle where the average Mach number is 2.88. Experiments were carried out for three different momentum flux ratios (J =0.5, 1.0, 1.5). A half-nozzle was introduced to measure heat transfer on the inner walls of the nozzle using Infrared thermography. Pressure measurements using PSP and oil flow visualization were also conducted to understand the heat transfer. From the oil flow visualization and heat transfer results, it was found that the area around the hole influenced by recirculation vortexes exhibited high heat transfer coefficients, showing up to 5 times higher values compared to the freestream. Furthermore, as the momentum flux of the jet increased, both the heat transfer augmentation area and the heat transfer coefficient also increased. To analyze the heat transfer characteristics between the nozzle and flat surface, comparisons were made using dimensionless heat transfer coefficients. The nozzle exhibited higher heat transfer in a smaller interaction area compared to that of a flat surface, but the average heat transfer coefficient near the hole was lower. Accordingly, distinct thermal treatment strategies should be employed for nozzles and flat surfaces, especially near injection holes. These insights could be valuable for the thermal design of rockets and other supersonic/hypersonic mobility systems. [ABSTRACT FROM AUTHOR]

The paper presents the methodology and results of experimental works concerning temperature of burnishing process. The research was carried out during disk burnishing of external cylindrical surfaces on a universal lathe CDS 6250 BX-1000 with severe parameters. As workpiece material steel S235JR has been selected. For temperature measurements infrared thermography method was chosen. This technique has a lot of advantages, the main is that it is non-contact technique and therefore there is no disturbance of the temperature field. In presented research infrared camera E95 produced by FLIR® Systems Inc. was used. Test results indicates the slight influence of process parameters on burnishing temperature. [ABSTRACT FROM AUTHOR]

This work presents the experimental and finite element (FE) simulations to investigate the behavior of both unstiffened and anisogrid composite cylindrical shells subjected to low‐velocity axial impact. Impact damage has been an epidemic problem for composite structures. Even subjected to a low‐velocity impact, thin‐walled composite structures may sacrifice its load‐carrying capacity considerably due to various modes of failure. A low cost, reliable and innovative manufacturing process is proposed for the production of anisogrid cylindrical lattice structures. Initially, test coupons are fabricated as per American Society for Testing of Materials (ASTM) standards and inspected using infrared (IR) thermography to find the imperfections incurred during fabrication. The test coupons without defects were only taken into account for material characterization. FE simulations were carried out on both the unstiffened and anisogrid shells using LS‐DYNA® for a series of low‐velocity impacts. Also these shell structures were subjected to impact loading experimentally for the validation of the numerical results. The results of these studies indicate that the anisogrid model presented in this work possesses a great load‐carrying capacity than an unstiffened shell under dynamic loading conditions, also the weight of the structure has been reduced up to 51.27%. Numerical simulation results are in good agreement with the experimental data, having less than 11.56% of maximum deviation on the energy absorption value. [ABSTRACT FROM AUTHOR]

Prohibitive equipment cost and certain export regulations are the major obstacles to the widespread adoption of infrared (IR) thermography when evaluating building envelopes. In this work, we propose the use of an affordable and easily available camera as a first step of making the technology accessible. Combined with image post-processing, we hypothesize that a low-cost, low-resolution, and consumer-grade device can provide an economic alternative for the periodic evaluation of building envelopes. Following a market survey, the Seek Thermal Compact (STC) was chosen for evaluation. The STC was able to accurately measure the temperature of surfaces and distinguish small thermal anomalies (3 mm in diameter), and the IR images can be post-processed to reasonably estimate the anomaly areas. The STC was particularly effective when images were taken within 1.75 m from the surface. The 1.75 m distance did not pose a challenge in this study, as the goal was to mount the selected IR camera on an unmanned aerial vehicle for the surveys. The small size and weight of the STC were also useful. The results from the analysis of the capability of the STC and the image post-processing techniques may help form the basis of future investigations aiming at lowering the cost of building thermographic surveys.

A synergistic set of NDT techniques, including I–V analysis, UVF imaging, IR thermography, and EL imaging, supports a diagnostics methodology developed in this work to qualitatively and quantitatively identify a wide range of PV defects. The methodology is based on (a) the deviation of the module electrical parameters at STC from their nominal values, for which a set of mathematical expressions was developed that provide an insight into potential defects and their quantitative impact on the module electrical parameters, and (b) the variation analysis of EL images captured at a sequence of bias voltages for a qualitative investigation on the spatial distribution and strength of the defects. The synergy of these two pillars, supported by UVF imaging, IR thermography, and I–V analysis cross-correlating their findings, makes the diagnostics methodology effective and reliable. It was applied on c-Si and pc-Si modules operating from 0–24 years, exhibiting a diversity of defects of varying severity, either pre-existing or formed by natural ageing or externally induced degradation. Defects such as EVA degradation, browning, corrosion in the busbar/interconnect ribbons, EVA/cell-interface delamination, pn-junction damage, e−+hole recombination regions, breaks, microcracks, finger interruptions, and passivation issues are detected. Degradation factors triggering a cascade of internal degradation processes through cause and effect are analysed and additional models are proposed for the temperature pattern under current mismatch and corrosion along the busbar, further empowering the cross-correlation of NDT results. Power degradation was determined from 1.2% in 2 years of operation to more than 50% in modules with film deposition.

Introduction: Burn wound depth assessments are an important component of determining patient prognosis and making appropriate management decisions. Clinical appraisal of the burn wound by an experienced burn surgeon is standard of care but has limitations. IR thermography is a technology in burn care that can provide a non-invasive, quantitative method of evaluating burn wound depth. IR thermography utilizes a specialized camera that can capture the infrared emissivity of the skin, and the resulting images can be analyzed to determine burn depth and healing potential of a burn wound. Though IR thermography has great potential for burn wound assessment, its use for this has not been well documented. Thus, we have conducted a systematic review of the current use of IR thermography to assess burn depth and healing potential.Methods: A systematic review and meta-analysis of the literature was performed on PubMed and Google Scholar between June 2020-December 2020 using the following keywords: FLIR, FLIR ONE, thermography, forward looking infrared, thermal imaging + burn*, burn wound assessment, burn depth, burn wound depth, burn depth assessment, healing potential, burn healing potential. A meta-analysis was performed on the mean sensitivity and specificity of the ability of IR thermography for predicting healing potential. Inclusion criteria were articles investigating the use of IR thermography for burn wound assessments in adults and pediatric patients. Reviews and non-English articles were excluded.Results: A total of 19 articles were included in the final review. Statistically significant correlations were found between IR thermography and laser doppler imaging (LDI) in 4/4 clinical studies. A case report of a single patient found that IR thermography was more accurate than LDI for assessing burn depth. Five articles investigated the ability of IR thermography to predict healing time, with four reporting statistically significant results. Temperature differences between burnt and unburnt skin were found in 2/2 articles. IR thermography was compared to clinical assessment in five articles, with varying results regarding accuracy of clinical assessment compared to thermography. Mean sensitivity and specificity of the ability of IR thermography to determine healing potential <15 days was 44.5 and 98.8 respectively. Mean sensitivity and specificity of the ability of FLIR to determine healing potential <21 days was 51.2 and 77.9 respectively.Conclusion: IR thermography is an accurate, simple, and cost-effective method of burn wound assessment. FLIR has been demonstrated to have significant correlations with other methods of assessing burns such as LDI and can be utilized to accurately assess burn depth and healing potential. [ABSTRACT FROM AUTHOR]