Добірка наукової літератури з теми "Surface thermometry"
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Статті в журналах з теми "Surface thermometry":
1
Augustin, Silke, and Marc Schalles. "New publication of the VDI/VDE guideline 3520 “Surface temperature measurement with contact thermometers” – contents and background of the development." Journal of Sensors and Sensor Systems 12, no. 1 (June 26, 2023): 197–204. http://dx.doi.org/10.5194/jsss-12-197-2023.
Анотація:
Abstract. Temperature measurement at the surface of solids by means of contact thermometers has its own metrological characteristics, which are in contrast to characteristics of the measurement with immersed contact thermometers. They significantly influence the accuracy and the measurement uncertainty of the measured temperature and its deviations. Up to now, no national or international guideline exists which deals with the determination of the static and dynamic measurement deviations. Therefore, the guideline committee “VDI/VDE-GMA FA 4.62 Contact Thermometry” has developed the new VDI (Association of German Engineers) and VDE (Association for Electrical, Electronic and Information Technologies) guideline 3520 “Surface temperature measurement with contact thermometers”. It contains information about the most important properties of contact surface thermometers and error sources, and it presents typical measurement results for various applications. In addition, the parameters influencing the measurement result and test equipment for their determination are described, and concrete examples of thermometer data sheets are given.
2
Dolibog, Patrycja, Barbara Pietrzyk, Klaudia Kierszniok, and Krzysztof Pawlicki. "Comparative Analysis of Human Body Temperatures Measured with Noncontact and Contact Thermometers." Healthcare 10, no. 2 (February 9, 2022): 331. http://dx.doi.org/10.3390/healthcare10020331.
Анотація:
Body temperature measurement is one of the basic methods in clinical diagnosis. The problems of thermometry—interpretation of the accuracy and repeatability of various types of thermometers—are still being discussed, especially during the current pandemic in connection with the SARS-CoV-2 virus responsible for causing the COVID-19 disease. The aim of the study was to compare surface temperatures of the human body measured by various techniques, in particular a noncontact thermometer (infrared) and contact thermometers (mercury, mercury-free, electronic). The study included 102 randomly selected healthy women and men (age 18–79 years). The Bland–Altman method was used to estimate the 95% reproducibility coefficient, i.e., to assess the degree of conformity between different attempts. Temperatures measured with contact thermometers in the armpit are higher than temperatures measured without contact at the frontal area of the head. The methods used to measure with contact thermometers and a noncontact infrared thermometer statistically showed high measurement reliability. In order to correctly interpret the result of measuring human body temperature, it is necessary to indicate the place of measurement and the type of thermometer used.
3
Mlačnik, Vid, and Igor Pušnik. "A Traceable Spectral Radiation Model of Radiation Thermometry." Applied Sciences 13, no. 8 (April 15, 2023): 4973. http://dx.doi.org/10.3390/app13084973.
Анотація:
Despite great technical capabilities, the theory of non-contact temperature measurement is usually not fully applicable to the use of measuring instruments in practice. While black body calibrations and black body radiation thermometry (BBRT) are in practice well established and easy to accomplish, this calibration protocol is never fully applicable to measurements of real objects under real conditions. Currently, the best approximation to real-world radiation thermometry is grey body radiation thermometry (GBRT), which is supported by most measuring instruments to date. Nevertheless, the metrological requirements necessitate traceability; therefore, real body radiation thermometry (RBRT) method is required for temperature measurements of real bodies. This article documents the current state of temperature calculation algorithms for radiation thermometers and the creation of a traceable model for radiation thermometry of real bodies that uses an inverse model of the system of measurement to compensate for the loss of data caused by spectral integration, which occurs when thermal radiation is absorbed on the active surface of the sensor. To solve this problem, a hybrid model is proposed in which the spectral input parameters are converted to scalar inputs of a traditional scalar inverse model for GBRT. The method for calculating effective parameters, which corresponds to a system of measurement, is proposed and verified with the theoretical simulation model of non-contact thermometry. The sum of effective instrumental parameters is presented for different temperatures to show that the rule of GBRT, according to which the sum of instrumental emissivity and instrumental reflectivity is equal to 1, does not apply to RBRT. Using the derived models of radiation thermometry, the uncertainty of radiation thermometry due to the uncertainty of spectral emissivity was analysed by simulated worst-case measurements through temperature ranges of various radiation thermometers. This newly developed model for RBRT with known uncertainty of measurement enables traceable measurements using radiation thermometry under any conditions.
4
Kirilova, Martina, Virginia Toy, Jeremy S. Rooney, Carolina Giorgetti, Keith C. Gordon, Cristiano Collettini, and Toru Takeshita. "Structural disorder of graphite and implications for graphite thermometry." Solid Earth 9, no. 1 (February 27, 2018): 223–31. http://dx.doi.org/10.5194/se-9-223-2018.
Анотація:
Abstract. Graphitization, or the progressive maturation of carbonaceous material, is considered an irreversible process. Thus, the degree of graphite crystallinity, or its structural order, has been calibrated as an indicator of the peak metamorphic temperatures experienced by the host rocks. However, discrepancies between temperatures indicated by graphite crystallinity versus other thermometers have been documented in deformed rocks. To examine the possibility of mechanical modifications of graphite structure and the potential impacts on graphite thermometry, we performed laboratory deformation experiments. We sheared highly crystalline graphite powder at normal stresses of 5 and 25 megapascal (MPa) and aseismic velocities of 1, 10 and 100 µm s−1. The degree of structural order both in the starting and resulting materials was analyzed by Raman microspectroscopy. Our results demonstrate structural disorder of graphite, manifested as changes in the Raman spectra. Microstructural observations show that brittle processes caused the documented mechanical modifications of the aggregate graphite crystallinity. We conclude that the calibrated graphite thermometer is ambiguous in active tectonic settings.
5
Pearce, J. V., F. Edler, A. Fateev, G. Sutton, A. Andreu, and G. Machin. "Enhancing process efficiency through improved temperature measurement: the EMPRESS projects." Journal of Physics: Conference Series 2554, no. 1 (July 1, 2023): 012003. http://dx.doi.org/10.1088/1742-6596/2554/1/012003.
Анотація:
Abstract EMPRESS 2 is a European project to enhance the efficiency of high value manufacturing processes by improving temperature measurement and control capability. This project seeks to address four contemporary thermometry challenges in this sector, and new developments from this and its predecessor project, EMPRESS, will be described: • Below 1000°C many industrial processes require reliable surface thermometry e.g. welding, coating, forging and forming. Conventional non-contact surface thermometry techniques e.g. thermal imaging are prone to large errors (tens of degrees) due to reflected thermal radiation and unknown emissivity. Contact thermometry approaches are prone to similarly large errors. Traceable imaging phosphor thermometry is being developed to overcome these difficulties, and is being combined with quantitative thermography to determine emissivity for thermometry over wide fields of view. • Above 1300°C sensor drift is a significant unaddressed issue for casting, forging and heat treatment, causing large errors. There is a need for more stable sensors and standardisation of at least one new thermocouple type to fill the gap from 1300°C to 1800°C. This is being addressed through improved Pt-Rh thermocouples and optimisation of double-walled mineral insulated, metal sheathed thermocouples by mitigating insulation breakdown and drift effects. • Combustion temperature measurement is very challenging and traceability is almost non-existent; for example, thermocouple measurements of flame temperatures can be in error by hundreds of degrees. A ‘standard flame’ that can be transported to users’ sites has been developed, and is being deployed in several high value manufacturing and industrial applications to a) demonstrate the possibility of reducing flame temperature uncertainties by at least an order of magnitude and b) for the first time to demonstrate in-situ traceability to the International Temperature Scale of 1990 (ITS-90). • Many processes are not amenable to any conventional thermometry techniques due to inaccessibility, ionising radiation, electromagnetic interference, and contamination; here methods based on optical fibres are ideal but there are no traceable calibration techniques for such sensors currently available. A suite of different fibre-optic thermometers and calibration techniques is being developed to address this. In some cases (ionising radiation) darkening of the fibre is a problem, and this is being overcome by the development of novel thermometry approaches based on practical ‘hollow core’ fibres.
6
Goss, L. P., A. A. Smith, and M. E. Post. "Surface thermometry by laser‐induced fluorescence." Review of Scientific Instruments 60, no. 12 (December 1989): 3702–6. http://dx.doi.org/10.1063/1.1140478.
7
Liu, Siyu, Yu Huang, Yong He, Yanqun Zhu, and Zhihua Wang. "Review of Development and Comparison of Surface Thermometry Methods in Combustion Environments: Principles, Current State of the Art, and Applications." Processes 10, no. 12 (November 28, 2022): 2528. http://dx.doi.org/10.3390/pr10122528.
Анотація:
Temperature is one of the most important parameters in the combustion processes. Accurate surface temperature can help to gain insight into the combustion characteristics of various solid or liquid fuels, as well as to evaluate the operating status of combustion power facilities such as internal combustion engines and gas turbines. This paper mainly summarizes and compares the main surface thermometry techniques, from the aspects of their principles, current state of development, and specific applications. These techniques are divided into two categories: contact-based thermometry and non-intrusive thermometry. In contact-based thermometry, conventional thermocouples as well as thin-film thermocouples are introduced. These methods have been developed for a long time and are simple and economical. However, such methods have disadvantages such as interference to flow and temperature field and poor dynamic performance. Furthermore, this paper reviews the latest non-intrusive thermometry methods, which have gained more interest in recent years, including radiation thermometry, laser-induced phosphorescence, liquid crystal thermography, the temperature-sensitive paint technique, and the temperature-indicating paint technique. Among them, we highlighted radiation thermometry, which has the widest measurement ranges and is easy to acquire results with spatial resolution, as well as laser-induced phosphorescence thermometry, which is not interfered with by the emissivity and surrounding environment, and has the advantages of fast response, high sensitivity, and small errors. Particularly, laser-induced phosphoresce has attracted a great deal of attention, as it gets rid of the influence of emissivity. In recent years, it has been widely used in the thermometry of various combustion devices and fuels. At the end of this paper, the research progress of the above-mentioned laser-induced phosphorescence and other techniques in recent years for the surface thermometry of various solid or liquid fuels is summarized, as well as applications of combustion facilities such as internal combustion engines, gas turbines, and aero engines, which reveal the great development potential of laser-induced phosphorescence technology in the field of surface thermometry.
8
Dowell, L. Jonathan. "Fluorescence Thermometry." Applied Mechanics Reviews 45, no. 7 (July 1, 1992): 253–60. http://dx.doi.org/10.1115/1.3119756.
Анотація:
The fluorescence of rare-earth-doped ceramic phosphors depends on temperature. Particularly, the fluorescence lifetime is decreased by temperature. This dependence makes the fluorescence suitable for measuring temperature. This paper describes the physics of the fluorescence of these ceramics, noting the works of Forster, Dexter, Inokuti, Hirayama, and others. Next, it outlines the several advantages of fluorescence thermometry. These advantages include (a) measurement of temperature by transfer to measurement standards for time, (b) remote sensing for surface thermometry, (c) high speed of measurement relative to many physical and mechanical phenomena, (d) narrow-spectrum optical sensing suitable for hostile electrical and luminous environments, and (e) the transfer of calibration standards for precise thermometry. The paper presents engineering considerations for realizing these advantages. It presents parameter-estimation techniques that allow measurement of the temperature-dependent fluorescence parameters. It describes instrumentation techniques that transfer the measurement of temperature to measurement of units of time, with instrument calibration by atomic standards. It also discusses other measurement and instrumentation details.
9
Johnson, Karen J., Priya Bhatia, and Edward F. Bell. "Infrared Thermometry of Newborn Infants." Pediatrics 87, no. 1 (January 1, 1991): 34–38. http://dx.doi.org/10.1542/peds.87.1.34.
Анотація:
An infrared thermometer, the FirstTemp, was tested among newborn infants by comparing tympanic membrane temperature measurements in three operating modes, "Cal-tympanic," "Cal-surface," and "Cor-tympanic," with nearly simultaneous tympanic membrane, rectal, and axillary temperature measurements using other standard methods. The FirstTemp underestimated other measurements of body temperature in the "Cal-tympanic" mode and overestimated them in the "Cor-tympanic" mode. In the "Cal-surface" mode, the First-Temp readings were significantly lower than tympanic membrane temperatures measured with a thermistor probe and electronic thermometer (mean difference 0.2°C) but not significantly different from rectal or axillary temperatures. According to these results, the FirstTemp can be used reliably in the "Cal-surface" mode but not in the "Cal-tympanic" or "Cor-tympanic" mode. Its speed and ease of operation offer significant advantages over traditional clinical methods of temperature measurement.
10
Jonsson, Patrik, and Mats Riehm. "Infrared Thermometry in Winter Road Maintenance." Journal of Atmospheric and Oceanic Technology 29, no. 6 (June 1, 2012): 846–56. http://dx.doi.org/10.1175/jtech-d-11-00071.1.
Анотація:
Abstract There is significant interest among road authorities in measuring pavement conditions to perform appropriate winter road maintenance. The most common monitoring methods are based on pavement-mounted sensors. This study’s hypothesis is that the temperature distribution in a pavement can be measured by means of a nonintrusive method to retrieve the topmost pavement temperature values. By utilizing the latest infrared (IR) technology, it is possible to retrieve additional information concerning both road temperatures and road conditions. The authors discovered that surface temperature readings from IR sensors are more reliable than data retrieved from traditional surface-mounted sensors during wet, snowy, or icy road conditions. It was also possible to detect changes in the road condition by examining how the temperatures in wheel tracks and in between the wheel tracks differ from a reference dry road condition. The conclusion was that nonintrusive measurement of the road temperature is able to provide an increase in relation to the knowledge about both the road temperature and the road condition. Another conclusion was that the surface temperature should not be considered as being equal to the ground temperatures retrieved from traditional surface-mounted sensors except under conditions of dry, stable roadways.
Дисертації з теми "Surface thermometry":
1
Suda-Cederquist, Keith David. "Near-Wall Thermometry via Total Internal Reflection Fluorescence Micro-Thermometry (TIR-FMT)." Thesis, Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14530.
Анотація:
To effectively design systems of microchannels it is necessary for scientists and engineers to understand thermal transport characteristics of microchannels. To experimentally determine the convective heat transfer coefficient of microchannels it is necessary to measure both the bulk and surface temperature fields. This investigation aims to develop a technique, named Total Internal Reflection Fluorescent Micro-Thermometry (TIR-FMT), to measure the temperature of water within several hundred nanometers of a wall--effectively, the surface temperature of the wall. In TIR-FMT, an evanescent-wave is generated in the water near the wall. The intensity of this evanescent-wave decays exponentially with distance from the wall. A fluorophore if illuminated by the evanescent-wave can absorb a photon. Excited fluorophores subsequently emit red-shifted photons, which are called fluorescence. The probability of a fluorescent emission is temperature-dependent. Therefore, by monitoring the intensity of the fluorescence a correlation can be made to the temperature of the region of illumination. Using the TIR-FMT technique the temperature dependence of the fluorescence intensity from buffered fluorescein (pH=9.2) was determined to be 1.35%/C. TIR-FMT can be used to measure the temperature of a fluorophore solution within 600 nm of a wall across a temperature range of 12.5-55C. The average uncertainties (95% confidence) of the temperature measured was determined to be 2.3C and 1.5C for a single 1.5x1.5 and #956;m pixel and the entire 715x950 and #956;m viewfield. By spatial averaging, average uncertainties of 2.0C and 1.8C were attained with spatial resolutions of 16x16 and 100x100 and #956;m, respectively.
2
Kim, Myeongsub. "Microscale optical thermometry techniques for measuring liquid phase and wall surface temperatures." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/43754.
Анотація:
Thermal management challenges for microelectronics are a major issue for future integrated circuits, thanks to the continued exponential growth in component density described by Moore¡¯s Law. Current projections from the International Technology Roadmap for Semiconductors predict that local heat fluxes will exceed 1 kW/cm2 within a decade. There is thus an urgent need to develop new compact, high heat flux forced-liquid and evaporative cooling technologies.
Thermometry techniques that can measure temperature fields with micron-scale resolution without disturbing the flow of coolant would be valuable in developing and evaluating new thermal management technologies. Specifically, the ability to estimate local convective heat transfer coefficients, which are proportional to the difference between the bulk coolant and wall surface temperatures, would be useful in developing computationally efficient reduced-order models of thermal transport in microscale heat exchangers.
The objective of this doctoral thesis is therefore to develop and evaluate non-intrusive optical thermometry techniques to measure wall surface and bulk liquid temperatures with O(1-10 micronmeter) spatial resolution. Intensity-based fluorescence thermometry (FT), where the temperature distribution of an aqueous fluorescent dye solution is estimated from variations in the fluorescent emission intensity, was used to measure temperatures in steady Poiseuille flow at Reynolds numbers less than 10. The flow was driven through 1 mm square channels heated on one side to create temperature gradients exceeding 8 ¡ÆC/mm along both dimensions of the channel cross-section. In the evanescent-wave fluorescence thermometry (EFT) experiments, a solution of fluorescein was illuminated by evanescent waves to estimate the solution temperature within about 300 nm of the wall. In the dual-tracer FT (DFT) studies, a solution of two fluorophores with opposite temperature sensitivities was volumetrically illuminated over most of the `cross-section of the channel to determine solution temperatures in the bulk flow. The accuracy of both types of FT is determined by comparing the temperature data with numerical predictions obtained with commercial computational fluid dynamics software. The results indicate that EFT can measure wall surface temperatures with an average accuracy of about 0.3 ¡ÆC at a spatial resolution of 10 micronmeter, and that DFT can measure bulk water temperature fields with an average accuracy of about 0.3 ¡ÆC at a spatial resolution of 50 micronmeter in the image plane. The results also suggest that the spatial resolution of the DFT data along the optical axis (i.e., normal to the image plane) is at least an order of magnitude greater than the depth of focus of the imaging system.
3
Khalid, Ashiq Hussain. "Development of phosphor thermometry systems for use in development gas turbine engines." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/development-of-phosphor-thermometry-systems-for-use-in-development-gas-turbine-engines(f01316f9-4622-4a6d-b2d0-611a9191b5eb).html.
Анотація:
The pursuit for improved engine efficiency is driving the demand for accurate temperature measurement inside turbine engines. Accurate measurement can allow engines to be operated closer to their design limits to improve thermal efficiency. It can enable engineers to verify mechanical integrity, provide better prediction of component life, validate CFD and other design tools and aid the development for leaner more efficient engines. Unfortunately, experimentally measuring surface temperatures under harsh rotating conditions is challenging. This EngD study conducted by Ashiq Hussain Khalid at the University of Manchester and Rolls-Royce plc, reviews the rationale of using phosphor thermometry over existing methods, including thermocouples, pyrometry and thermal paints/melts, which lack detail, accuracy, or are too expensive for continuous testing. Although phosphor thermometry exhibits desirable characteristics, the high temperature and fast rotating engine environment presents some challenges that would need to be addressed before a successful measurement system can be implemented. Examples of such issues include: rising blackbody radiation, restricted optical access, fibre optic constraints and limited time period to collect data. These factors will impose measurement limits and greatly influence the design philosophy of the system, including phosphor choice, phosphor lifetime characteristics, bonding technique, excitation/detection methodologies and probe design. Taking these into consideration, the research focuses on the development of phosphor thermometry systems for use in development gas turbine engines, with measurement solutions for specific engine components. The high pressure turbine blade was given research priority. A number of phosphors including YAG:Tb, YAG:Tm. Y2O3:Eu and Mg3F2GeO4:Mn were investigated and characterised in terms of intensity and lifetime decay, with increasing temperature up to 1500oC. Spectral analysis and absolute intensity measurements established emission peaks and permitted comparative quantitative analysis to optimise system setup. The intensity of phosphor emission relative to Planck's blackbody radiation was also performed. YAG:Tm under 355nm illumination was found to exhibit the highest emission intensity at high temperatures, and because its spectral emission peak at 458nm was the lowest, its advantage in terms of blackbody radiation was further amplified. For rotating components, an upper temperature limit is reached based on the emission intensity at rising blackbody radiation levels and the system's ability to detect fast decays. A lower limit is reached based on the quenching temperature, probe design and rotational velocity. There are different methods to correct the distorted decay waveform as it traverses through the acceptance cone of the fibre. A phosphor selection criterion, taking into consideration these limitations, was successfully applied for various rotating engine components. The optical layout was setup and tested on stationary and rotating cases under laboratory conditions using similar design constraints, including fibre choice, maximum permissible lens size and target distances. A series of tests validated design methodologies and assumptions to enable testing on full scale rotating engine components. Mg3F2GeO4:Mn, using 355nm illumination, was found to be the most suitable phosphor for the HP drive cone. The estimated performance under the expected rotational speeds was found to be 624-812°C with a standard uncertainty of ±0.99%. YAG:Tm, illuminated with 355nm, was found to be the most promising phosphor for high pressure turbine blade measurements. The performance under the expected rotational speeds was found to be 1117-1375°C with a standard uncertainty of ±0.97%. This is better than other competing technologies that are currently available for temperature measurement of rotating turbine blades.
4
Hashemi, Jazi Seyed Amir [Verfasser], Christoph J. [Akademischer Betreuer] Brabec, Lars [Gutachter] Zigan, and Christoph J. [Gutachter] Brabec. "A Contactless Solid Surface Temperature Determination Using Phosphor Thermometry / Seyed Amir Hashemi Jazi ; Gutachter: Lars Zigan, Christoph J. Brabec ; Betreuer: Christoph J. Brabec." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2021. http://d-nb.info/1237107814/34.
5
Chadli, Saïd. "Modélisation et réalisation d'un multicapteur microcontrôlé à couches minces, pour la mesure ambulatoire des températures de surface." Rouen, 1993. http://www.theses.fr/1993ROUES037.
Анотація:
Au cours de cette étude, nous mettons en évidence les différents problèmes qui se posent lorsque l'on désire mesurer la température d'une surface au moyen d'une sonde de contact. Nous proposons une étude théorique du comportement thermophysique d'une sonde active, thermorégulée destinée à la mesure fine, précise et instantanée des températures superficielles. Divers prototypes de transducteurs y sont décrits, aboutissant au modèle coplanaire retenu pour sa fonctionnalité. Nous exposons aussi les procédés qui ont permis la réalisation du transducteur en technologie couches minces. Nous décrivons enfin le système de gestion du transducteur ainsi que le logiciel associé permettant la régulation et la mesure en temps réel. Le mémoire s'achève par la présentation et l'analyse critique d'un ensemble de résultats de mesure sur diverses surfaces
6
Katz, Amandine. "Développement du thermomètre Δ47 appliqué sur coccolithes : de la calibration en laboratoire à l’applicabilité au registre sédimentaire". Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCC187.
Анотація:
Le géothermomètre Δ47 est basé sur la relation entre l’abondance des liaisons 13C–18O des carbonates et la température de calcification. Ce proxy contourne potentiellement les limites des autres thermomètres (δ18O, Mg/Ca) pour reconstruire les paléo-températures des océans, expliquant son développement exponentiel depuis dix ans. Cette thèse teste pour la première fois le potentiel et les limites de la thermométrie Δ47 sur les coccolithes, des nannofossiles calcaires produits par des organismes calcifiants dans la zone photique. Ces biominéraux calcitiques et ubiquistes constituent une part importante de l’archive sédimentaire. Des cultures in vitro nous ont permis d’établir que trois espèces de coccolithes actuelles enregistrent la même relation Δ47 – T que la calcite inorganique, alors qu'elles présentent de très larges effets vitaux en δ18O (±5‰). Nous concluons que ces espèces de coccolithes d'importance géologique ne présentent pas d’effets vitaux en Δ47. Nous avons ensuite appliqué le Δ47 à l’étude des sédiments enregistrant l’événement d’anoxie océanique du Toarcien (–183 Ma) au cours duquel les reconstructions de températures restent encore ambigües, notamment du fait de la méconnaissance de la composition isotopique en oxygène de l’eau de mer. Sur la base des données Δ47 acquises, nous proposons des températures élevées (de l’ordre de 36°C), mais restant relativement stables sur l'intervalle d'étude. En couplant ces températures aux données de δ18O des carbonates, nous suggérons une variation importante du δ18O de l'eau de mer dans le Bassin de Paris lors de la mise en place des faciès black shales. Enfin, sur des sédiments pélagiques subactuels, l’une des espèces étudiées présente des déséquilibres isotopiques en Δ47 non observés en culture et explicables par d’autres paramètres environnementaux comme l’intensité lumineuse. Cette thèse illustre le potentiel du thermomètre Δ47 des coccolithes en différents contextes, ouvrant un vaste champ d’application de reconstruction des paléo-environnements sur le Méso-CénozoïqueThe Δ47 geothermometer relies on the relationship between the 13C–18O abundance in carbonateand temperature of calcification. This proxy has the potential to overcome limitations of other thermometers(δ18O, Mg/Ca) to reconstruct oceanic paleotemperatures. This thesis evaluates for the first time the potentialand the limitations of the Δ47 thermometry of the coccoliths, the calcareous nannofossils produced byorganisms calcifying in the photic zone. These calcitic and ubiquitous biominerals represent an importantpart of the sedimentary archive. In vitro cultures allow us to establish that three modern coccoliths speciesrecord the same Δ47–T relation than inorganic calcite, although exhibiting substantial δ18O vital effects(±5‰). We conclude that these coccoliths species do not present any Δ47 vital effect. We subsequentlyapplied the Δ47 proxy to sediments from the Toarcian oceanic anoxic events (–183 Ma) during which thetemperatures reconstructions are still elusive, mainly due to the unknown oxygen isotopic composition ofseawater. On the basis of our Δ47 data, we infer relatively high, yet steady temperatures (around 36°C) duringthe examined interval. By combining these Δ47-derived temperatures to carbonate δ18O data, we can suggestdrastic change in the seawater δ18O composition in the Paris Basin at the onset of black shale deposition. Acore top calibration of Δ47 of coccoliths revealed that one of the studied cultured species exhibits Δ47disequilibrium that is accountable by other environmental parameters, such as light irradiance in the naturalenvironment. Thus, this thesis illustrates the potential of the coccolith Δ47 thermometer in different settings,opening a wide range of application to reconstruct the palaeoenvironments over the Meso-Cenozoic Eras
7
Lechner, Valentin. "Experimental study of LOX/CH4 flames in rocket engines." Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPAST040.
Анотація:
Utiliser le méthane comme carburant dans les moteurs fusées présente beaucoup d'avantages mais la combustion avec de l'oxygène pur à haute pression reste mal comprise. D'un point de vue thermodynamique, le méthane et l'oxygène partagent des valeurs de point critique très similaires, ce qui rend difficile la prédiction du mélange des ergols, l'accrochage, la stabilité et la structure de la flamme. De plus, quand le méthane est injecté en excès, des aérosols peuvent être produits, pouvant obstruer les lignes, endommager la turbine et réduire le rendement.Une mise à jour approfondie des connaissances sur la combustion LOX/CH4 est donc nécessaire. Ce défi est relevé au sein du consortium composé du laboratoire EM2C, de l'ONERA, du CNES et d'ArianeGroup. Deux campagnes d'essais sont menées sur le banc MASCOTTE de l'ONERA visant à étudier trois sujets centraux : la structure de la flamme, les transferts thermiques aux parois et la production d'aérosols. Dans ce but, divers diagnostics expérimentaux sont mis en œuvre simultanément pendant des essais à feu à haute pression.Différents diagnostics d'imagerie sont mis en place pour analyser la structure de la flamme et des jets liquides. Malgré les difficultés d'acquisition rencontrées dans ces conditions extrêmes, les analyses révèlent une structure de flamme complexe. En régime subcritique, les mécanismes d'atomisation et d'évaporation dominent. La flamme est alors bien plus ouverte et plus longue qu'à de plus hautes pressions, où les mécanismes de mélange diffusifs prévalent. Caractériser l'accrochage de la flamme reste un défi. En effet, un anneau de glace, probablement d'eau, entoure et masque le pied de la flamme. Des mécanismes de formation sont proposés et un cycle temporel de croissance/destruction est mis en avant. Sa présence affecte fortement la visualisation de la flamme, et peut conduire à des interprétations erronées de sa topologie.Pour la première fois à MASCOTTE, la phosphorescence induite par laser (LIP) est mise en place. Diverses méthodes LIP existent mais ne sont pas bien adaptées aux conditions de MASCOTTE : large gamme de températures, transitoires thermiques et environnement diphasique. C'est pourquoi une méthode spécifique a été mise au point (Full Spectrum Fitting method). Elle exploite la dépendance spectrale à la température, permettant des mesures instantanées de 100 à 900 K avec une précision de 17 K, sans dépendance à l'énergie d'excitation laser. Une analyse détaillée des données met en évidence les modes de transfert de chaleur prédominants, étudie l'influence des points de fonctionnement et compare les données expérimentales avec un modèle de transferts thermiques de paroi, particulièrement bien adapté pour déduire les caractéristiques convectives de l'écoulement à la paroi.Différents diagnostics sont mis en œuvre pour caractériser les aérosols. Une sonde intrusive prélève les particules et les gaz brûlés en aval de la flamme. Les particules sont prélevées sur des grilles adaptées à des analyses par microscopie électronique à transmission (TEM). Les images détaillées de leurs morphologies révèlent qu'il s'agit de suies. Les gaz sont analysés par chromatographie en phase gazeuse. Ceci permet d'identifier des molécules précurseurs des suies comme le benzène et l'acétylène. Les suies sont quantifiées temporellement par extinction laser. Des post-traitements dédiés sont développés et diverses hypothèses sont discutées pour expliquer les variations spatiales de production de suiesUsing methane as a fuel in rocket engines would have many advantages but the combustion with pure oxygen at high pressure remains poorly understood. From a thermodynamic point of view, methane and oxygen share very similar critical point values, making it challenging to predict propellant mixing, flame anchoring, stability and structure. Moreover, when methane is injected in excess, aerosols can be produced, which can clog the lines, damage the turbine, and reduce the efficiency.Therefore, a thorough update of the knowledge of LOX/CH4 combustion is necessary. These challenges are tackled within the consortium composed of EM2C laboratory, ONERA, CNES, and ArianeGroup. Two test campaigns are carried out at the MASCOTTE facility from ONERA, aiming to study three central topics: the flame structure, wall heat transfers, and aerosol production. To this end, various experimental diagnostics are implemented simultaneously during high-pressure hot-fire tests.Various imaging diagnostics are implemented to analyze the flame structure and the dense liquid jets. Despite the acquisition difficulties encountered in these extreme conditions, the analyses reveal a complex flame structure. In the subcritical regime, atomization and evaporation mechanisms dominate. The flame is much more opened and longer than at higher pressures, where diffusive mixing mechanisms prevail. Characterizing flame anchoring remains a challenge. A water ice ring surrounding, and masking, the flame foot has been identified. Formation mechanisms are proposed, and a growth/destruction temporal cycle is highlighted. Its presence strongly affects flame visualizations, and may lead to misinterpretations of its topology.Laser-induced phosphorescence (LIP) is implemented for the first time at MASCOTTE. Various LIP methods exist, but they are not well suited to the MASCOTTE conditions: wide temperature range, thermal transients, and two-phase flow environment favoring laser absorption/diffusion. Therefore, a specific method, the Full Spectrum Fitting method (FSF method), has been developed. It exploits the spectral dependence on temperature, enabling instantaneous measurements from 100 to 900 K with a precision of 17 K, with no dependence on the laser excitation energy. A detailed data analysis highlights the predominant wall heat transfer modes, studies the influence of the operating points, and compares the experimental data with a wall heat transfer model, which is particularly well suited for deducing the convective properties of the flow.Three diagnostics are used to characterize aerosols. An intrusive probe samples particles and burnt gases downstream of the flame. The particles are sampled on TEM grids and analyzed by Transmission Electron Microscopy. Detailed images of the aerosol morphology reveal that the particles are soot. Combustion products are analyzed by gas chromatography. This makes it possible to identify soot precursor molecules such as benzene and acetylene. Soot are quantified temporally by laser extinction. A dedicated post-processing method is developed and various hypotheses are discussed to explain the spatial variations of the soot production downstream of the flame
8
RIBEAUDEAU, MARION. "Elaboration et caracterisation de films de niobium deposes sur cuivre. Determination de la resistance de surface de supraconducteurs par thermometrie sous vide." Paris 6, 1999. http://www.theses.fr/1999PA066429.
Анотація:
Le developpement des cavites acceleratrices nb/cu elaborees par pulverisation magnetron est motive par leurs applications possibles dans les grands projets necessitant de hauts gradients. Neanmoins, afin de satisfaire aux criteres de fonctionnement imposes par les futurs collisionneurs lineaires, les performances hf de ces cavites doivent etre ameliorees. L'augmentation rapide de la resistance de surface avec l'amplitude du champ hf constitue la limitation principale de la technologie couche mince. Dans l'optique de comprendre et reduire ces dissipations energetiques, nous avons entrepris une serie d'etudes sur echantillons nb/cu. Nous avons optimise les conditions d'elaboration des films. L'augmentation de la temperature de depot et de la puissance appliquee au magnetron ainsi que la diminution de la pression de decharge ont conduit a une augmentation sensible du rrr des couches minces. Des analyses de la composition chimique des films par methodes nucleaires ont confirme une teneur reduite en impuretes legeres (o, c et h) ainsi que l'absence de pollution du niobium par diffusion du cuivre dans les joints de grains. Nous avons developpe et valide une nouvelle methode de mesure de la resistance de surface par thermometrie sous vide. Cette methode adaptee a la cavite te 0 1 1 deja utilisee au laboratoire a permis de determiner directement la resistance de surface d'echantillons nb/cu a 1,7k et a 4,2k. Nous avons etudie l'influence de l'etat de surface du substrat cuivre sur la resistance de surface du film de niobium en realisant des depots sur des substrats de rugosite tres variable. Les observations de la surface des films par microscopie electronique a balayage ont mis en evidence l'existence de defauts micrometriques de croissance, en particulier sur les echantillons rugueux. Les tests hf par thermometrie sous vide de ces echantillons ont permis d'etablir une correlation entre la forte densite de ces defauts et la degradation de la resistance de surface du depot, a bas champ comme a fort champ. Les resultats de ces recherches sur echantillons ont beneficie aux cavites 1,5 ghz. Les premiers tests hf sont encourageants (q o = 2 10 1 0 a bas champ et e a c c = 25 mv/m). Pour obtenir des resultats reproductibles et ameliorer encore les performances hf des cavites, il est primordial de poursuivre l'optimisation de la preparation de surface du cuivre avant le depot.
9
Park, Keunhan. "Thermal Characterization of Heated Microcantilevers and a Study on Near-Field Radiation." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14597.
Анотація:
Recently, remarkable advances have been made in the understanding of micro/nanoscale energy transport, opening new opportunities in various areas such as thermal management, data storage, and energy conversion. This dissertation focuses on thermally-sensed nanotopography using a heated silicon microcantilever and near-field thermophotovoltaic (TPV) energy conversion system.
A heated microcantilever is a functionalized atomic force microscope (AFM) cantilever that has a small resistive heater integrated at the free end. Besides its capability of increasing the heater temperature over 1,000 K, the resistance of a heated cantilever is a very sensitive function of temperature, suggesting that the heated cantilever can be used as a highly sensitive thermal metrology tool. The first part of the dissertation discusses the thermal characterization of the heated microcantilever for its usage as a thermal sensor in various conditions. Particularly, the use of heated cantilevers for tapping-mode topography imaging will be presented, along with the recent experimental results on the thermal interaction between the cantilever and substrate.
In the second part of the dissertation, the so-called near-field TPV device is introduced. This new type of energy conversion system utilizes the significant enhancement of radiative energy transport due to photon tunneling and surface polaritons. Investigation of surface and bulk polaritons in a multilayered structure reveals that radiative properties are significantly affected by polariton excitations. The dissertation then addresses the rigorous performance analysis of the near-field TPV system and a novel design of a near-field TPV device.
10
Hsieh, Tsung-Lin, and 謝宗霖. "Suitiability of Multispectral Radiation Thermometry (MRT) Emissivity Models Predicting Aluminum Alloy Surface Temperature." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/74629552045644137961.
Анотація:
碩士國立成功大學
機械工程學系碩博士班
96
Experiments are conducted to investigate the surface emissivity characteristics for five different aluminum alloys, AL1100、AL2024、AL5083、AL6061、AL7005 at 600K, 700K and 800K. Six multispectral radiation thermometry (MRT) emissivity models, HRR, IST, IST* (another form of IST), IWS, WLT and WLT* (another form of WLT) are examined for the suitability of predicting aluminum alloy surface temperature. The goal of this study is to find the best MRT emissivity model which can well compensate the aluminum emissivity variations and accurately infer temperature. Wavelength range from 2.91μm to 4.13μm is chosen because of the high stability in emissivity measurement. For aluminum emissiveity behaviors, (1)overall, emissiveity decreases with increasing wavelength; (2)emissivity decreases between 600K and 700K, but increases between 700K and 800K. Increase in emissivity is contributed to the surface oxidation and discoloration which cause the surface color change from light gray to dark black; (3) at high temperature, aluminum alloys with more magnesium constituent cause the increase in emissivity which results in a much stronger alloy effect; (4)emissivity reaches steady state after the 2nd hour due to the surface oxidation becoming fully developed. For the examination of MRT emissivity models on aluminum, (1)most models achieve high accuracy in temperature prediction, except IWS and WLT emissivity models. HRR shows the best overall performance and stability; (2)for least-squares technique, the closer the inferred emissivity value and real one, the more accurate inferred temperature; (3)increasing wavelength number does not significantly improve measurement accuracy while applying MRT. However, compared with SRT and DWRT, MRT indeed provides better performance; (4)overall, constant emissivity value acquired with increasing heating time enhances temperature prediction; (5)results from the error analysis show good stability of experimental operation and MRT emissivity models predicting aluminum alloy surface temperature.
Частини книг з теми "Surface thermometry":
1
Müller, W., H. Piazena, A. R. Thomsen, and Peter Vaupel. "Thermography and Thermometry in wIRA-Hyperthermia." In Water-filtered Infrared A (wIRA) Irradiation, 55–67. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92880-3_4.
Анотація:
AbstractContact-free temperature determination is based on the measurements of electromagnetic radiation. The corresponding physical laws are related to the properties of black bodies. This background allows for the development of thermometric and thermographic systems for remote temperature measurements. Precise absolute temperature data, required in hyperthermia, do not only depend on the technical quality of the systems (hardware and software) and their calibration, but also depend on accurate determination of the emissivity of human skin. Pyrometers are restricted to temperature measurements within a small area (measurement spot), while thermographic cameras allow measurements across a relatively large region on the target area in real time. The subdivision of the IR image into spatially separated pixels allows access to temperature data of small areas on the skin and thus combines thermometry and thermography. Quality assurance standards of the European Society of Hyperthermic Oncology for water-filtered IR-A-hyperthermia (wIRA-HT) are met, except for the accuracy of the absolute temperature. Since the relation between the temperatures at the skin surface and in deeper tissue layers, considering irradiation and heating time, in wIRA-HT can be assessed, the temperature needed for efficient thermal treatment of superficial tumors within superficial tissue layers can therefore be achieved in a controlled manner.
2
Nakagawa, Yuki, Noor Agha Nassary, Kiichi Fukuyama, and Ikuo Kobayashi. "Measurement of Udder Surface Temperature in Cows Using Infrared Thermometer." In Advances in Intelligent Systems and Computing, 429–34. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-23204-1_43.
3
Ohlsson, K. E. Anders, Ronny Östin, and Thomas Olofsson. "Sol-Air Thermometer Measurement of Heat Transfer Coefficient at Building Outdoor Surfaces." In Springer Proceedings in Energy, 329–38. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-00662-4_28.
4
Dimitraki, Lamprini, Kyriaki Devlioti, Basile Christaras, Nikolas Arampelos, and Maria Chatziangelou. "The P-Wave Ultrasonic Velocity and Infrared Thermometer Nondestructive Techniques for Estimating the Surface Weathering and the Depth of the Consolidation Liquid on Historical Monuments." In 10th International Symposium on the Conservation of Monuments in the Mediterranean Basin, 243–50. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-78093-1_24.
5
Brock, Fred V., and Scott J. Richardson. "Thermometry." In Meteorological Measurement Systems. Oxford University Press, 2001. http://dx.doi.org/10.1093/oso/9780195134513.003.0006.
Анотація:
Air temperature is one of the most fundamental of all meteorological measurements and directly effects our everyday lives. It has been measured for centuries, using countless different techniques. One might assume that accurate air temperature measurements are readily made. Indeed, it is possible to make very accurate air temperature measurements but it can be a remarkably hard task, especially when limitations such as power consumption, reliability, and cost are involved. Errors in the measurement of air temperature in excess of 2 to 3°C are not uncommon in many networks. Errors of this magnitude are generally acceptable for the general public who is most interested in what clothes to wear for the day. However, numerical models at all scales of motion (mesoscale, synoptic scale, or climate models) are greatly affected by errors even as large as 1°C. Errors of just 1°C in a mesoscale model have been shown to be the deciding factor between no storms initiated and intense storms (Crook, 1996). In addition, errors as small as 0.2°C can change the prediction of a global climate model, depending on its dependency on initial conditions (DeFelice, 1998). Measurement of air temperature near the surface of the earth is facilitated by the vast array of temperature sensors and supporting electronic modules that are readily available. Accuracy is limited not by technology but by our ability to use it and by our ability to avoid exposure error, that is, to provide adequate coupling with the atmosphere. The preferred temperature scales are Celsius and Kelvin. These scales can be used almost interchangeably (except when absolute temperature is required) because a temperature difference of 1 K is equal to a temperature difference of 1°C. The Fahrenheit scale is still in general use by the U.S. public. Some common temperature reference points are shown in table 4-1. The triple point of water is the temperature and pressure where all three phases, gas, liquid, and solid, can coexist. Temperature sensors can be categorized according to the physical principle that they use: thermal expansion, thermoelectric, electrical resistance, electrical capacitance and some other effects.
6
Bowden, F. P., and D. Tabor. "Surface Temperature of Rubbing Solids." In The Friction and Lubrication of Solids, 33–57. Oxford University PressOxford, 2001. http://dx.doi.org/10.1093/oso/9780198507772.003.0003.
Анотація:
Abstract When one solid body slides over another most of the work done against the frictional force opposing the motion will be liberated as heat between the surfaces. This heat will be carried away from the surfaces by conduction and radiation, but quite primitive calculations indicate that even under moderate conditions of speed and load the surface temperatures may reach very high values. It is of course difficult to measure these temperatures by ordinary methods. If we embed thermometers or thermocouples in the solids near the rubbing surfaces, we find that the temperature rise is very small. This is partly because of the relatively large heat capacity of the thermometer (or thermocouple), but is mainly due to the fact that the temperature falls off very rapidly as we move away from the actual rubbing interface. We may, however, measure the surface temperatures directly by using the surfaces themselves as a thermometer.
7
"Characteristics of surfaces." In The Fundamentals of Radiation Thermometers, 51–73. Taylor & Francis Group, 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487-2742: CRC Press, 2016. http://dx.doi.org/10.1201/9781315366883-4.
8
Lawton, B., and G. Klingenberg. "Electrical Methods Of Temperature Measurement." In Transient Temperature in Engineering and Science, 153–241. Oxford University PressOxford, 1996. http://dx.doi.org/10.1093/oso/9780198562603.003.0004.
Анотація:
Abstract By electrical methods of temperature measurement we mean thermocouples, thermistors, hot-wire anemometry, and other electrical resistance gauges. Optical methods of temperature measurement are described in Chapter 5. Essentially, this chapter describes thermocouples and resistance thermometers that are suitable for measuring transient temperatures. Typically, such devices may be constructed in the form of a wire, for insertion into fluids and solids, or of a thin film for attachment to surfaces; but other arrangements are possible.
9
Mccormmach, Russell. "The Question." In Speculative Truth, 131–50. Oxford University PressNew York, NY, 2004. http://dx.doi.org/10.1093/oso/9780195160048.003.0008.
Анотація:
Abstract As he did heat, Cavendish interpreted light in Newton’s way: light is a body consisting of particles emitted from luminous bodies at a known velocity. To find its vis viva, he looked to Michell’s experiment with a light-mill. From the observed speed of rotation of the vane and other details of the experiment, and from the assumption that light is perfectly reflected from the copper of the vane, he calculated the momentum and vis viva of sunlight falling each second on one and a half square feet of surface. Translating this result into its mechanical effect, he showed that the rate of vis viva of sunlight falling on that surface exceeds the work done by two horses, two horsepower. By his theory, this very considerable mechanical power imparted by sunlight has an exact heat equivalence: if the same quantity of light were to be absorbed instead of reflected, the equivalent heat would register on the thermometer. Upon this reasoning, Cavendish proposed two experiments on sunlight, with the intention of carrying them out himself.
10
Sandhu, Navjot, Suvidha Sehrawat, and Atul Pratap Singh. "Sensing Applications of Ionic Liquids." In Ionic Liquids: Eco-friendly Substitutes for Surface and Interface Applications, 380–401. BENTHAM SCIENCE PUBLISHERS, 2023. http://dx.doi.org/10.2174/9789815136234123010020.
Анотація:
The Molten salts having melting points near to or less than room temperature is termed ionic liquids (ILs). A full IL unit generally comprises two oppositely charged ions with a remarkable size difference, i.e., bulky cation and comparatively small anion. The ILs are also labelled as future solvents due to their design flexibility and greener approach. Owing to their large number of favourable characteristics, such as less toxicity, good solvating capacity, high conductivity, nonvolatility, super sensitivity, selectivity and electrochemical stability, these ILs have provided a broader range of applicability in the field of sensing. ILs are proven to be of good use in the area of sensors as well as biosensors, i.e., optical sensing, thermometric sensing, electrochemical sensing and fluorescent sensing, etc. The ILs can be tailored by changing cations and anions as per the demand of the applications. In the present chapter, various aspects of ILs, including the use of these ILs in various sensing applications, have been explored and summed up to present an organized view for the researcher community as well as general readers.
Тези доповідей конференцій з теми "Surface thermometry":
1
Xavier, P., S. Petit, and F. Grisch. "Temperature Uncertainty Improvements of Surface Phosphor Thermometry for Imaging Applications." In Laser Applications to Chemical, Security and Environmental Analysis. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/lacsea.2022.lth3e.3.
Анотація:
Temperature uncertainty improvements of surface phosphor thermometry imaging are reported, with the intensity-ratio method. Analysis of optical filters/post-processing spatial filters with Mg4FGeO6:Mn4+ thermographic phosphors results in a ≈1% temperature uncertainty between 300 and 825 K.
2
Kim, Myeongsub, and Minami Yoda. "Fluorescence Thermometry for Measuring Wall Surface and Bulk Fluid Temperatures." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22884.
Анотація:
Cooling the next generation of microelectronics with heat fluxes of more than 1 kW/cm2 over hot spots less than 103 μm2 in area will require new single- and two-phase thermal management technologies with micron-scale addressability. Thermal transport models using heat transfer correlations may be the most efficient approach for the initial design and optimization of such micron-scale heat exchangers which will likely involve arrays of microchannels. It is unclear, however, whether classic macroscale convective heat transfer correlations are applicable to these devices given their complex geometries and the possibility of significant thermal coupling between channels. There is therefore a need for new techniques that can measure both bulk fluid and wall surface temperatures at micron-scale spatial resolution without disturbing the flow of coolant. We report here the use of a nonintrusive technique, fluorescence thermometry (FT), to determine bulk fluid temperatures and, for the first time, wall surface temperatures, with a spatial resolution of O(10 μm) for water flowing through a heated channel. Fluorescence thermometry is typically used to estimate temperature distributions in water flows based on variations in the emission intensity of a fluorophore dissolved in the water. The accuracy of FT can be improved by taking the ratio of the emission signals from two different fluorophores (dual-tracer FT, or DFT) to eliminate variations in the signal due to (spatial and temporal) variations in the excitation intensity. In this work, two temperature-sensitive fluorophores, fluorescein and sulforhodamine B, with emission intensities that increase and decrease, respectively, with increasing temperature, are used to further improve the accuracy of the temperature measurements. Temperature profiles were measured in the steady Poiseuille flow of water at Reynolds numbers of 3.3 and 8.3 through a 1 mm square channel heated with a thin-fim heater. Temperatures in the bulk flow were measured using DFT with an average uncertainty of 0.2 °C at a spatial resolution of 30 μm. Fluid temperatures within the first 0.3 μm next to the wall were measured using evanescent-wave illumination of a single temperature-sensitive fluorophore with an average uncertainty of less than 0.2 °C at a spatial resolution of 10 μm. The results are compared with numerical predictions, which suggest that the fluid temperatures within 0.3 μm are effectively the wall surface temperature.
3
Kontis, Konstantinos, and Norihiko Yoshikawa. "Surface Thermometry by Laser-Induced Fluorescence in High Speed Flows." In 20th AIAA Applied Aerodynamics Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2002. http://dx.doi.org/10.2514/6.2002-3154.
4
Abou Nada, Fahd, Johan Hult, Christoph Knappe, Mattias Richter, Stefan Mayer, and Marcus Aldén. "A First Application of Thermographic Phosphors in a Marine Two-Stroke Diesel Engine for Surface Temperature Measurement." In ASME 2014 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/icef2014-5417.
Анотація:
Phosphor thermometry is applied for the first time in a large-bore two-stroke diesel engine. The work proves the practicality of phosphor thermometry in large-bore engines. The experiments were conducted on the MAN 4T50ME-X marine research engine equipped with an optical cylinder head. By employing a thin surface coating of CdWO4 phosphor, cycle resolved temperature measurements of the cylinder wall were obtained. Motored and fired engine operations were tested at engine loads covering the low and medium engine load range. Phosphor thermometry proved to be successful in retrieving the temperature with standard deviations ranging around 1–8 K. Experimental considerations like detector linearity, coating thickness and an automated phosphor calibration routine will be addressed.
5
Serrano, Justin R., and Leslie M. Phinney. "Micro-Raman Thermometry of Laser Heated Surfaces." In ASME 2007 InterPACK Conference collocated with the ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/ipack2007-33571.
Анотація:
Optically powered devices are typically irradiated by high intensity lasers and rely on the temperature excursion generated by the laser for operation. While numerical modeling can estimate the temperature profile of the irradiated devices, only direct measurements can determine the actual device temperatures. Available surface thermometry techniques, such as infrared imaging, scanning thermal microscopy and thermoreflectance are generally incompatible with an optical powering scheme, the micron-scale layer thicknesses of microsystem devices, or both. In this paper we discuss the use of micro-Raman thermometry to obtain the first spatially-resolved temperature measurements of various polycrystalline silicon (polysilicon) surfaces heated with an 808 nm continuous wave (CW) laser at a 60° angle of incidence. The micron-scale resolution of the micro-Raman technique permitted mapping of the surface temperature in the vicinity of the heating laser spot and throughout the device. In addition to discussing the requirements for accurate data collection, the implications of optical interference on the heated structures are also considered.
6
Hirsch, Sacha, Nicolas Fdida, Cornelia Irimiea, Sylvain Petit, Baptiste Dejean, Philippe Reulet, Benoît Fond, and Guillaume Pilla. "Surface Phosphor Thermometry behind a Water Film in a Rectangular Cooling Channel." In The 8th World Congress on Momentum, Heat and Mass Transfer. Avestia Publishing, 2023. http://dx.doi.org/10.11159/icmfht23.128.
7
Kearney, Sean P., Leslie M. Phinney, and Michael S. Baker. "Raman Thermometry of an Electro-Thermal Microactuator." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-79615.
Анотація:
Experimentally measured temperature profiles along the micron-scale beam of a working thermal actuator are reported for the first time. Using a surface Raman scattering technique, temperature measurements are obtained in a noncontact fashion with submicron spatial resolution and to within an uncertainty of better than ±10 K. The experimental data are used to validate computational predictions of the actuator thermal performance with reasonable agreement between the data and predicted temperatures.
8
Gottschalk, K., and Cs Mészáros. "IR thermometry for heat and mass transfer analysis of surface drying of fruit." In 2012 Quantitative InfraRed Thermography. QIRT Council, 2012. http://dx.doi.org/10.21611/qirt.2012.327.
9
Whalen, S. A., L. W. Weiss, C. D. Richards, D. F. Bahr, and R. F. Richards. "Characterization of the Thermodynamic Working Cycle in a MEMS-Based Micro Heat Engine." In ASME 2003 International Mechanical Engineering Congress and Exposition. ASMEDC, 2003. http://dx.doi.org/10.1115/imece2003-41426.
Анотація:
This work examines the conversion of thermal to mechanical energy in a micro heat engine by characterizing the heat engine’s working cycle. Results are given for dynamic measurements of pressure, volume, and temperature throughout the working cycle of the engine. Engine pressure is determined from the deformation of the two membranes in contact with the working fluid. A Michelson interferometer is used to measure the center deflection and displacement profile of both of these membranes. Pressure is determined from the membrane deflection using experimental static pressure-deflection curves. Engine temperature is measured using electrical resistance thermometry, via a micro resistance thermometer fabricated on the surface of a silicon membrane exposed to the working fluid in the engine cavity.
10
Arndt, Christoph M., Patrick Nau, and Wolfgang Meier. "Assessment of Camera-Based 2D Phosphor Surface Thermometry in a Gas Turbine Model Combustor." In Laser Applications to Chemical, Security and Environmental Analysis. Washington, D.C.: OSA, 2020. http://dx.doi.org/10.1364/lacsea.2020.lw4e.4.
Звіти організацій з теми "Surface thermometry":
1
Abel, Mark, Thomas Beecham, Samuel Graham, Sean Patrick Kearney, Justin Raymond Serrano, and Leslie Mary Phinney. Noncontact surface thermometry for microsystems: LDRD final report. Office of Scientific and Technical Information (OSTI), October 2006. http://dx.doi.org/10.2172/899367.
2
Goss, Larry P., and Michael E. Post. Surface Thermometry of Energetic Materials by Laser-Induced Fluorescence. Fort Belvoir, VA: Defense Technical Information Center, April 1988. http://dx.doi.org/10.21236/ada198094.