Application Of Thermography Research Articles

Analysis of Tensile Deformation Behavior in Friction Stir Welded P91-316LN Dissimilar Joints Using Infrared Thermography

This research article highlights the application of Infra red thermography (IRT) technique for analyzing the surface temperature variations during the tensile deformation. Few comparative tensile deformation tests were conducted on friction stir welded (FSW) P91-316LN dissimilar joints. The rise in temperature during plastic deformation is monitored under different welding and offset conditions and the deformation behavior with respect to time is visualized through IR thermal patterns.

Infrared Thermography Applied to Monitoring Musculoskeletal Adaptation to Training in Thoroughbred Race Horses

Infrared thermography has been used to help in diagnosing lameness. It is hypothesized that, if used in a routine basis, it could help in understanding musculoskeletal modifications during race training. This study aimed to evaluate thermal variation in the musculoskeletal regions of young Thoroughbred (TB) horses during their initial months of race training. Thermographic examinations were performed once every 2 weeks on 16 (10 male, 6 female) two-year-old TB racehorses, from arrival to the racetrack in June 2016, until January 2017, for a total of 16 evaluations. Thermographic imaging was performed using the appropriate protocol. Temperature (°C) was measured at the dorsal and palmar/plantar aspects of specific regions of interest (fetlock, metacarpal, metatarsal, carpal, tarsal, thoracolumbar, sacroiliac spine, and both hips). Initially, we found a thermal balance and all regions demonstrated a positive correlation with one another. However, a significant difference was noted between the left and right sides as training progressed. Four horses were withdrawn from the study after 50% of evaluations because of metacarpal conditions associated with training. Thermographic examination revealed changes before the clinical manifestation of these conditions. In conclusion, this study demonstrated that infrared thermography is an image technique that can facilitate understanding of musculoskeletal system modifications to race training and should be further investigated as a predictive tool to anticipate the occurrence of lesions.

Fabrication of Artificial Delamination Flaw Specimens and an Application of Active Thermography

Fabrication of Artificial Delamination Flaw Specimens and an Application of Active Thermography

The search for 'defects' by non-invasive techniques: development and application of pulsed-transmissive and reflective thermography in fiberglass material

The search for 'defects' by non-invasive techniques: development and application of pulsed-transmissive and reflective thermography in fiberglass material

Ocular thermography in contact lens wearers

AbstractThe infra‐red thermal images have been used in the past for measuring the ocular surface temperature, its main advantage being the non‐invasive means. It is well‐known for its ability to detect the pathological and physiological changes in the eye.There are a few studies about ocular surface temperature and contact lenses. Some authors found that insignificant changes in ocular surface. temperature in soft contact lenses did occur, but other authors described that the pre‐lens tear film in soft lens wearers is cooler than that of the non‐CL‐wearing eye, while the temperature of the post‐lens tear film beneath the CL is higher. Regarding hard and gas permeable corneal contact lenses, the changes are between 0.5–1.5°C compared to the naked eyes. However, gas permeable scleral contact lens seems not to modify the ocular surface temperature despite the presence of the tear film stagnation under the lens.This presentation will navigate in the scientific literature about the usability and applicability of ocular thermography in contact lens wearers.

Potential for the application of dynamic skin thermography after local hypothermia

Infrared thermography is one of the widely used non-invasive diagnostic methods. While the procedure is mainly used for early malignant tumor diagnostics, a potential application for thermography was proposed in cardiovascular, skin, autoimmune diseases, arthritis, Reynaud’s syndrome, burns, surgery and therapeutic treatment monitoring. The method of thermographic evaluation has not changed significantly since the end of 20th century. In this study we attempted to characterize the influence of skin capillary blood flow on surface temperature recuperation following local hypothermia. To improve sensitivity and standardize the procedure we developed a study protocol that involves minimizing or excluding the influence of external factors on study results. An original applicator was used to apply dosed hypothermia. Massive porcine tissue block was chosen as a passive model without active heat and mass transfer but with heat capacity, structure and heat dissipation characteristics similar to human tissues. 51 healthy volunteers were assigned to control group, while 16 patients with diabetes mellitus constituted the main study group. Cumulative temperature difference was calculated in all cases. It was 121,8 ± 70,8 °С×s in the control group, 95,6 ± 54,4 °С×s in the main study group and 307,2 ± 43,4 °С×s in the passive model. Based on the study results, we made the following conclusions: absence of heat and mass transfer in the passive model complicates heat balance recuperation due to layered structure of the skin; heat balance recuperation curve is an individual parameter and is not influenced by age or gender.

APPLICATION OF ACTIVE THERMOGRAPHY FOR DEFECTOSCOPY OF TECHNOLOGICAL EQUIPMENT ON OBJECTS OF THE NUCLEAR POWER PLANTS

The methodical and physical bases of the use of active thermography as a high-performance non-destructive method of control and defectoscopy of materials during thermovision monitoring of technological equipment at NPP objects are considered. The data of experimental research confirm the efficiency of the use of thermal and low-frequency electromagnetic activators in the thermographic defectoscopy. The features of the application of dynamic thermography and the influence of external activation sources on the thermal appearance of structural inhomogeneities and defects in materials are investigated. It is shown that the application of special methods of processing thermal images that take into account the amplitude-frequency and morphological features of thermoanomalies, allows to control the thermal display of energy-absorbing structures and defects, provide the possibility of their identification against the background of false thermoanomalies.

Thermographic examination of prick test reactions with local anesthetic

In allergology, skin diagnostic tests are divided into epicutaneous, cutaneous and intracutaneous. The prick test is one of the cutaneous tests used most often for the diagnosis of hypersensitivity to local anesthetics. In the case of hypersensitivity to the examined anesthetic and reaction to the histamine-containing solution (positive control), inflammation appears with an increase in the local temperature. This warming can be detected objectively with a thermal camera and can be used in the diagnostic process. This study was used to examine the capabilities of the infrared thermography application, in the prick test of both men and women, by comparing temperature changes and the intensity of allergic inflammation in the positive and negative controls in addition with a negative reaction to an allergen. A group of 115 patients—55 male (52%) and 60 female (48%), are included. All are examined for hypersensitivity to Mepivastesin, together with the positive and negative control. Skin temperature changes of the skin were examined with FLIR A320 thermal camera and the FLIR Reporter Professional software 2013—application used to process the thermal camera images and data. The statistical analysis shows a marked temperature difference between men and women. Similarities in temperature values are detected between the negative reactions to dental anesthetic and the negative control. However, the latter substantially differs from the data obtained with the positive control. Results of the research indicate the possible applications of the thermography diagnostics in evaluation of the prick test results.

Infrared Thermography Applied to Tree Health Assessment: A Review

The tree is a fundamental living being. It contributes to nature and climate behaviour, as well to urban greening. It is also a source of wealth and employment. Most tree health inspection techniques are invasive or even destructive. Infrared thermography (IRT) is not invasive, and it has shown advantages when applied for inspection to trees and wood to detect deterioration or voids that could compromise its structure, stability, and durability. This study reviews the literature about IRT applied to a tree health inspection. It is framed in the context of the importance of trees for the balance of ecosystems, and the different techniques to detect tree deterioration. It highlights the difference when applied to wood or trees and the main factors that have been proven to cause disturbances in the thermal pattern of trees. The IRT, as other non-destructive methods, does not distinguish what type of damage it is, nor its causative agent. However, it enables identifying healthy and deteriorated tissues. The technology is very promising since it reveals that is efficient, fast, economical, and sustainable.

Infrared Thermography Applied to the Study of Enzyme Kinetics

Kinetic analysis of enzyme activity typically relies on spectrophotometric detection of changes in product or substrate concentrations. Spectrophotometric detection can directly monitor enzyme activity when a suitable chromophore is involved in the reaction itself, or reaction progress can be tracked via a coupled reaction that involves a chromophore with quantifiable signal changes. An alternative, potentially universal strategy for tracking reaction rates involves monitoring the evolution of heat from the enzyme‐catalyzed reaction. The heat generated by a reaction can then be used to calculate the moles of product formed by taking into account the molar enthalpy change for conversion of substrate into product. As with other enthalpimetric approaches, e.g. isothermal titration calorimetry, analysis of the reaction is not dependent on the use of a specific chromophore, nor is it challenged by optically‐dense or heterogeneous samples. Such methodologies have been in use for decades using near‐adiabatic instrumentation to quantify the total heat change. More recently, infrared imaging technologies such as the 200USD FLIR ONE camera open new opportunities to analyze kinetics on the basis of the heat evolved by the enzyme‐catalyzed reaction. We report our preliminary work to demonstrate the proof‐of‐principle use of infrared thermography to track enzyme reaction rates. In addition, the unique advantages of IR imaging are well suited for applications of this approach in a biochemistry laboratory course setting.Support or Funding InformationNational Science Foundation DUE Award Number:1813313; “Collaborative Research: Visualizing Chemistry with Infrared Imaging”This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Low-rank sparse principal component thermography (sparse-PCT): Comparative assessment on detection of subsurface defects

Infrared Non-destructive Testing (IRNDT) applications are unequivocally expanded and portend a commodity to improve the quality of defect detection in different fields such as aviation and industrial methods to arts and archaeology. The proposed approach focuses on the application of low-rank sparse principal component thermography (Sparse-PCT or SPCT) to assess the advantages and drawbacks of the method for non-destructive testing. For benchmarking the approach, two types of infrared image sets are tested: the Square Pulse Thermography (SPT) method for two hybrid composites (carbon and flax fiber reinforced epoxy), and passive infrared test of Bell Tower and the University of L’Aquila (AQ) faculty’s wall infrared sets. The quantitative assessment of the approach is also compared for every method and indicate considerable segmentation performance where other similar approaches were not able to detect the defects. SPCT performance was compared to some popular decomposition methods such as principal component thermography (PCT), candid covariance-free incremental principal component thermography (CCIPCT), non-negative matrix factorization (NMF) using gradient descent (GD) or non-negative least square (NNLS). The comparative results demonstrate the considerable performance while the other methods failed.

Local wall heat transfer coefficient measurement in a packed bed of cylinders using infrared (IR) thermography technique and application of random packing of cylindrical particles inside concentric tube heat exchangers with water as working medium

Heat transfer enhancement is challenging area in which different techniques are utilized to dissipate the generated heat during operation. Packed beds are devices which enhance heat transport while being compact and are used in several applications such as energy storage, heat exchange devices, catalysis, food processing etc. In the present study, the behavior of wall heat transfer coefficient with randomized packing of equal aspect ratio cylinders is investigated. In this work, the local wall heat transfer coefficient is calculated from local wall temperature data obtained using infrared (IR) thermography in packed beds with randomized packing of cylinders under steady state conditions with water as the working fluid. The randomized packing of cylinders is done inside a concentric tube heat exchanger and the heat transfer enhancement is studied. Experiments are conducted for bed to equivalent particle diameter ratio 2 using random packing of mono-dispersed glass cylinders (dcyl = 6 mm and lcyl = 6 mm). The local wall temperatures are measured using an infrared (IR) camera while the fluid flow takes place through the packed beds. In literature, it is found that wall region contribution to heat transfer is above 90%. The comparison of enhancement in heat transfer for both packing of spheres and cylinders inside concentric tube heat exchangers is done and it is observed that the random sphere packing is superior to cylinder packing.

Prediction of healing in Category I pressure ulcers by skin blotting with plasminogen activator inhibitor 1, interleukin-1α, vascular endothelial growth factor C, and heat shock protein 90α: A pilot study

The prevention of progression of Category I pressure ulcers (PUs) to Category II or higher is important, as Category II or higher PUs are open wounds and have a higher infection risk. Prognosis prediction of Category I PUs is necessary to provide successful intensive care for PUs with impaired healing. We focused on skin blotting using plasminogen activator inhibitor 1 (PAI1), interleukin-1α (IL-1α), vascular endothelial growth factor C (VEGF-C), and heat shock protein 90α (HSP90α). This pilot study was conducted at long-term-care and general hospitals to examine the applicability of DESIGN-R and thermography; the feasibility of skin blotting technique; the biomarker candidates, PAI1, IL-1α, VEGF-C, and HSP90α; and sample size for prognosis prediction for Category I PUs. Patients aged >65 years underwent skin blotting, scoring for DESIGN-R, and took thermography images of their Category I PU site. Albumin signals were not detected in one out of three participants. PAI1, IL-1α, VEGF-C, and HSP90α were detected in 19 participants, among whom 11 participants could be followed up after one week. There was no difference in DESIGN-R score and skin surface temperature between normal and impaired healing groups, and the sample size was calculated as 16. In conclusion, the feasibility of skin blotting was confirmed. PAI1, IL-1α, VEGF-C, and HSP90α could be biomarker candidates for prognosis prediction for Category I PU and the combination of VEGF-C and HSP90α could be associated with the prognosis of Category I PU. We need to investigate 842 patients in a future study.

Comparison between thermal energy and acoustic emission for the fatigue behavior of steels

The paper is focused on the study of fatigue materials, using an energy approach, with the support of two different non-destructive techniques. Indeed, the analysis of the energy behavior was conducted by the simultaneous application of Acoustic Emission (AE) and Thermography (TH). The purpose of the paper was to compare and integrate the results obtained by the two methodologies to assess the fatigue behavior of materials. The experimental tests were carried out on flat steel specimens of steels commonly used for metal carpentry either under static loading or under sequences of increasing cyclic loading. The results allow to define the fatigue limit either by the thermography or by the acoustic emission and they are encouraging to continue the comparison and the integration between the two energetic methodologies.

Infrared thermography study as a complementary method of screening and prevention of muscle injuries: pilot study

ObjectiveTo evaluate thermography application as a complementary method in preventing muscle injury in professional soccer players. MethodsA longitudinal prospective study with 28 professional soccer players that composed a first division...

Enhancing defects characterization in pulsed thermography by noise reduction

In the field of NDT techniques for aeronautic components of composite materials, the development of automatic and robust approaches for defect detection is largely desirable for both safety and economic reasons. This paper introduces a novel methodology for the automatic analysis of thermal signals resulting from the application of pulsed thermography. Input thermal decays are processed by a proper FIR filter designed to reduce the measurement noise, and then modeled to represent both sound regions and defective ones. Output signals are thus fitted on an exponential model, which approximates thermal contrasts with three robust parameters. These features feed a decision forest, trained to detect discontinuities and characterize their depths. Several experiments on actual sample laminates have proven the increase of the classification performance of the proposed approach with respect to related ones in terms of the reduction of missing predictions of defective classes.

An Evaluation of the Implications of Thermography within the Healthcare Setting

Thermography has developed rapidly over the past fifty years; it has been refined into a sophisticated tool to measure temperature that may be used anywhere owing to the reduction in size of the apparatus used. This technique has also been used industrially to ensure product quality. However, for over fifty years this technology has been employed in medical research studies as it is a non-invasive tool that can be used to study human skin temperature (Ring 2010). The body’s physiological mechanisms yield heat and temperature variations may indicate the presence of disease (Gatt et al. 2015). Thermography is not a tool that requires a skilled technician, nor is it a test that needs to be applied physically to the desired area. It is a simple test can be performed by a simple click of a button and the subject’s temperature readings can be uploading on the manufacturer’s software (Jones 1998). Repeatability of this test has been applied with successful results (Balbinot et al. 2013). Over the past year, MCAST students in several faculties have observed first-hand the application of thermography as an indication of disease, making using the thermographic camera available on campus. Students from various disciplines could see how the heat-detecting camera being used for disease detection in addition to its applications in engineering, construction, and food technology. Using this research science and technology were linked to enhance the students’ learning experience and make them aware of a fresh approach on how humans can benefit from modern engineering in relation to health. The applications of thermography for disease detection and the understanding of its use is of the utmost importance for students following health-related courses, since thermography is a tool that may soon be available locally as research brings forth new beneficial practices in medicine. This paper appraises the importance of this tool within the health-care setting.

Perspective: Principles and specifications of photothermal imaging methodologies and their applications to non-invasive biomedical and non-destructive materials imaging

This article discusses a number of dynamic thermography techniques used for analysis of captured raw infrared images of objects. The most widely used, as well as state-of-the-art, modalities are outlined in terms of their operating principles and their specifications. Special attention is paid to truncated correlation photothermal coherence tomography, a novel method that provides high contrast and high resolution 3D images of objects. Applications of thermography in medical imaging, art analysis, and non-destructive imaging of industrial materials are discussed.

Local wall temperature mapping during flow boiling in a transparent microchannel

In this study the local two-phase heat transfer coefficients were obtained using wall temperature measurements and fluid saturation temperatures in a rectangular high-aspect-ratio (a=WchHch=22) polydimethylsiloxane (PDMS) microchannel with a hydraulic diameter of 192 μm. The experiments used FC-72 liquid with a mass flux of 7.37 kg m−2s−1 and various heat fluxes ranging between 3.34 and 61.95 kW m−2. Fluid saturation temperatures were determined by interpolating pressure measurements obtained with integrated silicon ceramic-based pressure sensors located near the inlet and outlet of the microchannel. The hydrodynamic and flow boiling characteristics of the microchannel were monitored using high frequency and high spatial resolution infrared thermography, with heat transfer coefficients obtained as a function of axial position, lateral position and time and at the inlet, middle and outlet sections of the microchannel. This enabled the effect of heat flux on local temperature, flow boiling heat transfer coefficient distribution and two-phase pressure drop to be determined. These results suggest that the two-phase heat transfer coefficient does not increase monotonically with the heat flux, and actually decreases under certain conditions. This work identifies that the heat transfer coefficient depends on the range of the heat flux and is correlated with vapour-liquid dynamics and liquid film thinning resulting in suspected dryout, observed simultaneously with the temperature measurements. The simultaneous application of high speed thermography and flow visualization has enabled uniquely detailed information to be obtained that is useful to a more detailed understanding of two-phase flow and bubble dynamics.

Zastosowanie termografii w medycynie – przegląd literatury

ABSTRAKT Wstęp: Celem doniesienia jest przedstawienie zastosowania zjawiska termoemisji w różnych dziedzinach medycyny z uwzględnieniem okulistyki. Zastosowanie tomografii: Dane w piśmiennictwie wskazują, że detekcja promieniowania podczerwonego, która jest emitowana przez różne obiekty, w tym tkanki ludzkie, może być wykorzystywana w medycynie. Termografia w medycynie najczęściej służy do oceny rozległości i nasilenia stanu zapalnego w badanej tkance na postawie zjawiska wysokiej termoemisji, czyli lokalnego wzmożonego ukrwienia i metabolizmu tkankowego. Używana jest w diagnostyce zapalenia stawów, skóry czy gałki ocznej. Wzrost temperatury obserwuje się w guzach nowotworowych takich jak czerniak oraz naczyniak. Obniżenie temperatury jako efekt zaburzeń ukrwienia stwierdza się w termografii dynamicznej w Zespole Raynauda, po zawale serca, po oparzeniach skóry oraz w niedokrwieniu siatkówki. Zaobserwowano, iż w zespole suchego oka oczy chore mają niższą temperaturę niż oczy zdrowe, co może wynikać z niższej emisji promieniowania podczerwonego przez zaburzony film łzowy. Wnioski: Termografia jest metodą nieinwazyjną, szybką oraz obiektywną, która może znaleźć w przyszłości zastosowanie w wielu dziedzinach medycyny, w tym w okulistyce.