Academic literature on the topic 'Infrared- Water mist'

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Journal articles on the topic "Infrared- Water mist"

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Sun, Zhongke, Zhen Wang, Zhongwei Chen, Zhihua Liu, Mo Liu, and Shuai Zhang. "Analysis of Infrared Radiation Intensity by Water-Mist Spraying in Ship Exhaust System." Journal of Physics: Conference Series 2112, no. 1 (November 1, 2021): 012019. http://dx.doi.org/10.1088/1742-6596/2112/1/012019.

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Abstract The infrared radiation intensity in 3~5μm of conventional ship exhaust system are so severe [1] that can be easily captured by detector. Therefore, it’s necessary to take measure like spraying water mist to decrease temperature of exhaust system in order to decrease infrared radiation intensity. In this paper, the calculation of infrared radiation intensity of conventional ship exhaust system with water-mist spraying will be given. The results show that the average and maximum infrared radiation intensity of the exhaust system can be reduced by 90.3% and 95.7% after water mist cooling.
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Władysiak, R., and P. Budzyński. "Structure of Water Mist Stream and its Impact on Cooling Efficiency of Casting Die." Archives of Foundry Engineering 12, no. 2 (April 1, 2012): 251–60. http://dx.doi.org/10.2478/v10266-012-0069-y.

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Structure of Water Mist Stream and its Impact on Cooling Efficiency of Casting Die The work is a continuation of research on the use water mist cooling in order to increase efficiency of die-casting aluminum alloys. The paper presents results of research and analysis process, spraying water and generated a stream of water mist, the effect of the type of nozzle, the nozzle size and shape of the emitting of the water mist on the wall surface of casting die on the microstructure and geometry of water mist stream and cooling efficiency. Tests were used to perform high-speed camera to record video in the visible and infrared camera. Results were used to develop a computerized image analysis and statistical analysis. The study showed that there are statistical relationships between water and air flow and geometry of the nozzle and nozzle emitting a stream of microstructure parameters of water mist and heat the incoming stream. These relationships are described mathematical models that allow you to control the generating of adequate stream of water mist and a further consequence, the cooling efficiency of casting die.
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Villa Caro, Raúl, Rodrigo Pérez Fernández, Julio M. Pernas Urrutia, and Filiberto Hernandez. "METHODOLOGY APPLIED TO STUDY WATER MIST AS AN INFRARED SIGNATURE SUPPRESSOR IN MARINE GAS TURBINES." International Journal of Maritime Engineering 165, A1 (July 10, 2023): 43–54. http://dx.doi.org/10.5750/ijme.v165ia1.815.

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This paper proposes a methodology for the reduction of marine gas turbine exhaust gas temperatures via water mist injection into exhaust gas ducts with the aim of reducing a ship’s infrared (IR) signature. Due to the difficulty of conducting live experimental tests on warships, Computational Fluid Dynamic (CFD) techniques can be employed to predict phase interaction behaviour (water mist and exhaust gases) within gas turbine exhausts. CFD techniques attempt to find numerical solutions to the equations that govern phase interaction phenomena through the setting and resolution of mathematical models.
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Balner, Dalibor, Karla Barčová, and Michal Dostál. "Attenuation of Infrared Radiation When Passing Through a Water Curtain." TRANSACTIONS of the VŠB – Technical University of Ostrava, Safety Engineering Series 12, no. 1 (March 28, 2017): 1–8. http://dx.doi.org/10.1515/tvsbses-2017-0001.

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Abstract This article focuses on the interaction of infrared (IR) radiation with water droplets. The main objective of the article is the production of water mist in order of evaluation the reduction in intensity of IR radiation. In the experiments described in this paper, a set of five different nozzles was used with various spray characteristics. The respective nozzles were gradually located between the IR radiation source and a detector and the attenuation of IR radiation was assessed. The reduction in IR radiation intensity was determined and IR radiation transmittance was calculated for the respective tested nozzles.
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He, Yue Jun, Bao Lin Ren, He Gang Xu, Wang Hua, and Chun Heng Li. "Experimental Investigation of the Water-Based Fog Screen System in Photoelectric Interference." Applied Mechanics and Materials 385-386 (August 2013): 1921–26. http://dx.doi.org/10.4028/www.scientific.net/amm.385-386.1921.

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The water-based fog screen system for photoelectric interference, with low cost, energy-saving and environmental features, is a new type of interference material. This article describes and investigates the physical characteristics of the water-based fog screen, the principle behind the interference of visible light, infrared and other electromagnetic waves using mist, the composition of the water-based fog screen system and its significance in military applications.
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Huang, Kuan-Tzu, and Yao-Hsien Liu. "Enhancement of Mist Flow Cooling by Using V-Shaped Broken Ribs." Energies 12, no. 19 (October 6, 2019): 3785. http://dx.doi.org/10.3390/en12193785.

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Substantial heat transfer enhancement can be achieved by cooling with air/water mist flow because of droplet impingement and liquid film/fragment evaporation on the heated surface, which leads to a high heat-removal rate. An experimental investigation was conducted in a square channel with continuous and broken V-shaped ribs. To generate a mist flow, micro droplets were introduced into the gas stream. The rib angle of attack was 45°, and the rib spacing-to-height ratios were 10 and 20. The air Reynolds number ranged from 7900 to 24,000, and the water-to-air volume flow ratio was less than 0.1%. The net heat inputs ranged from 1.1–3.1 W/cm2 and 3.4–9.4 W/cm2 for the air and mist flow cases, respectively. Because the deposited liquid fragments produced uneven temperature distribution on the heated surface, steady-state infrared thermography was used to visualize the heat transfer distribution. Two to seven times higher heat transfer was attained for the broken ribs when using the mist flow than when using air flow. This increase was mainly attributed to the broken structure, which facilitated liquid transport and enhanced liquid coverage. In addition, the broken ribs produced a smaller friction factor than continuous ribs. The broken structures were beneficial for higher thermal performance in the mist flow.
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Dombrovsky, Leonid A., Vladimir P. Solovjov, and Brent W. Webb. "Attenuation of solar radiation by a water mist from the ultraviolet to the infrared range." Journal of Quantitative Spectroscopy and Radiative Transfer 112, no. 7 (May 2011): 1182–90. http://dx.doi.org/10.1016/j.jqsrt.2010.08.018.

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Hagen, C. L., B. C. Lee, I. S. Franka, J. L. Rath, T. C. VandenBoer, J. M. Roberts, S. S. Brown, and A. P. Yalin. "Cavity ring-down spectroscopy sensor for detection of hydrogen chloride." Atmospheric Measurement Techniques 7, no. 2 (February 3, 2014): 345–57. http://dx.doi.org/10.5194/amt-7-345-2014.

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Abstract. A laser-based cavity ring-down spectroscopy (CRDS) sensor for measurement of hydrogen chloride (HCl) has been developed and characterized. The instrument uses light from a distributed-feedback diode laser at 1742 nm coupled to a high finesse optical cavity to make sensitive and quantifiable concentration measurements of HCl based on optical absorption. The instrument has a (1σ) limit of detection of <20 pptv in 1 min and has high specificity to HCl. The measurement response time to changes in input HCl concentration is <15 s. Validation studies with a previously calibrated permeation tube setup show an accuracy of better than 10%. The CRDS sensor was preliminarily tested in the field with two other HCl instruments (mist chamber and chemical ionization mass spectrometry), all of which were in broad agreement. The mist chamber and CRDS sensors both showed a 400 pptv plume within 50 pptv agreement. The sensor also allows simultaneous sensitive measurements of water and methane, and minimal hardware modification would allow detection of other near-infrared absorbers.
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Hagen, C. L., B. C. Lee, I. S. Franka, J. L. Rath, T. C. VandenBoer, J. M. Roberts, S. S. Brown, and A. P. Yalin. "Cavity ring-down spectroscopy sensor for detection of hydrogen chloride." Atmospheric Measurement Techniques Discussions 6, no. 4 (August 6, 2013): 7217–50. http://dx.doi.org/10.5194/amtd-6-7217-2013.

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Abstract. A laser-based cavity ring-down spectroscopy (CRDS) sensor for measurement of hydrogen chloride (HCl) has been developed and characterized. The instrument uses light from a distributed-feedback diode laser at 1742 nm coupled to a high finesse optical cavity to make sensitive and quantifiable concentration measurements of HCl based on optical absorption. The instrument has a (1σ) limit of detection of < 20 pptv in 1 min and has high specificity to HCl. The measurement response time to changes in input HCl concentration is < 15 s. Validation studies with a previously calibrated permeation tube setup show an accuracy of better than 10%. The CRDS sensor was preliminarily tested in the field with two other HCl instruments (mist chamber and chemical ionization mass spectrometry), all of which were in broad agreement. The mist chamber and CRDS sensors both showed a 400 pptv plume within 50 pptv agreement. The sensor also allows simultaneous sensitive measurements of water and methane, and minimal hardware modification would allow detection of other near-infrared absorbers.
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Wang, Baoming, Shengzong Ci, Mingzhe Zhou, Chengrui Di, Junwei Yu, Bo Zhu, and Kun Qiao. "Effects of Hygrothermal and Salt Mist Ageing on the Properties of Epoxy Resins and Their Composites." Polymers 15, no. 3 (January 31, 2023): 725. http://dx.doi.org/10.3390/polym15030725.

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Epoxy and epoxide composites have a wide range of outdoor applications wherein they are affected by ageing. In this study, epoxy casting plates and epoxy-based composite rods for use in overhead conductors were prepared. A concurrent investigation concerning the ageing of epoxy resins and their carbon fibre composites was carried out via artificially accelerated experiments under hygrothermal and salt mist conditions. The moisture penetration along the depth, water absorption, appearance, hardness, density of the epoxy resins, and variation patterns of the impact strength and tensile strength of the epoxy-based composites were investigated. The ageing mechanisms were explored using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Both ageing modes had essentially similar influences on the properties of the resins and their composites; moreover, they did not significantly affect the chemical structure and microstructure of the epoxy resin, with the physical adsorption of water primarily observed during the ageing process. The moisture absorption behaviour of the epoxy obeyed Fick’s law. Although the water penetration rate in the salt mist ageing mode was slightly higher than that in the hygrothermal ageing mode during the early ageing stage, it was essentially the same during the later stage. The final moisture absorption rate at saturation was approximately 1.1% under both modes. The flexural strengths and impact strengths of the composites in both ageing modes followed a similar trend. They decreased gradually with the ageing time and then stabilized at almost the same value. The flexural strength was reduced from 803 MPa to 760 MPa and the impact strength from 383 J/m2 to 310 J/m2, indicating a decrease of approximately 5.4% and 19%, respectively. The absorbed water during the ageing process caused micro-cracks at the interface between the fibres and resin, weakening the interfacial strength and reducing the mechanical properties of the composites.
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Dissertations / Theses on the topic "Infrared- Water mist"

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Lechêne, Sullivan. "Etude expérimentale et numérique des rideaux d'eau pour la protection contre le rayonnement thermique." Phd thesis, Université Henri Poincaré - Nancy I, 2010. http://tel.archives-ouvertes.fr/tel-00539894.

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Les rideaux d'eau sont des milieux semi-transparents constitués de gouttelettes d'eau dispersées dans l'air. Le but de ces rideaux ici n'est pas d'interagir avec la flamme dans une optique d'extinction mais plutôt d'agir en tant que boucliers radiatifs contre une forte source de chaleur. En effet, placés entre une source radiative et une cible à protéger, ils permettent de limiter la propagation du rayonnement grâce notamment au caractère absorbant et diffusant des gouttelettes d'eau. L'intérêt du brouillard d'eau réside dans la présence de fines gouttelettes d'eau. Elles possèdent, à quantité d'eau égale, une capacité d'atténuation du rayonnement largement supérieure à celle des techniques de «sprinklage», utilisant une quantité d'eau abondante constituée de gouttes de gros diamètres. Nous avons travaillé expérimentalement (réalisation d'un pilote) et numériquement (code BERGAMOTE) sur le rôle des conditions d'injection : pulvérisation descendante, ascendante, impactante, jets mutualisés en rampes, etc... pour quantifier et comprendre les phénomènes mis en jeu. On retiendra en particulier le fort couplage entre la dynamique des brouillards ou rideaux d'eau et leur propriété d'écran thermique. Il résulte également de ces travaux qu'une modification de la direction d'injection, tout en conservant la même quantité d'eau injectée, engendre de fortes variations sur la capacité d'atténuation du rideau, s'expliquant par la dynamique des sprays injectés. La taille et la concentration en gouttelettes d'eau (liée au temps de séjour des gouttes dans le domaine) apparaissent alors comme des paramètres cruciaux dans l'optique d'une optimisation de ces systèmes de protection.
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Nguyen, The Thuong. "Etude du vieillissement cutané par microspectroscopie vibrationnelle : mise en évidence d’altérations affectant le collagène I dermique." Thesis, Reims, 2013. http://www.theses.fr/2013REIMS034/document.

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La peau est un organe particulier de l'organisme dont la fonction principale est un rôle de protection vis-à-vis du milieu extérieur. Cette fonction est assurée grâce à la structure du tissu cutané en trois couches (épiderme, derme, hypoderme). Le derme est responsable de la résistance et de la souplesse de la peau. Le composant moléculaire majeur du derme est le collagène de type I, qui est fortement altéré au cours du vieillissement chronologique. Dans ce contexte, notre étude a pour objectif d'évaluer les modifications moléculaires du collagène dermique associées au vieillissement cutané par spectroscopies vibrationnelles (diffusion Raman et absorption infrarouge). Par déconvolution de la bande Amide I du signal Raman, nous avons mis en évidence, en fonction de l'âge de la peau, des modifications au niveau des interactions entre le collagène et les molécules d'eau ; ce qui reflète un espacement croissant des faisceaux de fibres de collagène au cours du vieillissement. En micro-imagerie infrarouge polarisée, le ratio des bandes Amide I/ Amide II permet d'évaluer l'orientation des fibres de collagène qui deviennent parallèles à la surface de la peau lors du vieillissement. Des expérimentations préliminaires ont également montré la possibilité de localiser sans marquage la jonction dermo-épidermique de la peau grâce aux caractéristiques spectrales du collagène de type IV. Une analyse ciblée de cette structure nécessite de développer de nouveaux instruments basés sur la spectroscopie en champ proche (Tip Enhanced Raman Scattering, NanoIR) ; ce qui devrait permettre de suivre les altérations du collagène de type IV au cours du vieillissement cutané
Skin is a particular organ of the body whose the main function is a protective role towards the external environment. This function is provided by the structure of skin tissues in three layers (epidermis, dermis, hypodermis). The dermis is responsible for the strength and elasticity of the skin. The major molecular component of the dermis is the type I collagen, which is strongly altered during chronological aging. In this context, our study aims at evaluating the molecular modifications of the dermal collagen associated with skin aging by vibrational spectroscopy (Raman diffusion and infrared absorption). Using curve-fitting of Raman Amide I band, modifications in the interactions between collagen and water molecules were highlighted depending of the donor age. Such result reflects an increasing spacing of the collagen fiber bundles during aging. In addition, the collagen fibers orientation can be evaluated from the amide I/ amide II ratio calculated in polarized infrared micro-imaging. It appeared that the collagen fibers become orientated parallel to the skin surface with aging. Preliminary experiments showed also the ability to localize in a label-free manner the dermo-epidermal junction of the skin using the spectral characteristics of type IV collagen. A precise analysis of this structure requires the development of new instruments based on near-field spectroscopy (Tip Enhanced Raman Scattering, NanoIR); which could permit to follow the collagen IV alterations during skin aging
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Conference papers on the topic "Infrared- Water mist"

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Liu, Xiaomin, Yongjin Liu, Qunnie Peng, Feiran Jie, and Delie Ming. "Calculation of Attenuation of Infrared Radiation Energy By Ship Water Mist." In 2019 IEEE 8th Joint International Information Technology and Artificial Intelligence Conference (ITAIC). IEEE, 2019. http://dx.doi.org/10.1109/itaic.2019.8785527.

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Wu, Cunqian, Haibin Wu, and Xinbing Chen. "Research on near-infrared polarization imaging based on water mist environment." In 2022 International Conference on Optoelectronic Materials and Devices, edited by Qiang Huang. SPIE, 2023. http://dx.doi.org/10.1117/12.2674153.

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Chen, Zhong-wei, Xin-gang Liang, Xiang-hua Xu, Hong-bin Wang, and Ling-jiang Zhang. "Infrared attenuation analysis of lognormal distribution water mist in the atmosphere windows." In International Symposium on Photoelectronic Detection and Imaging 2009, edited by Jeffery Puschell, Hai-mei Gong, Yi Cai, Jin Lu, and Jin-dong Fei. SPIE, 2009. http://dx.doi.org/10.1117/12.834517.

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Huang, Yi-Hsuan, Chiao-Hsin Chen, and Yao-Hsien Liu. "Non-Boiling Heat Transfer of Air/Water Mist Flow in a Square Duct With Orthogonal Ribs." In ASME 2016 Heat Transfer Summer Conference collocated with the ASME 2016 Fluids Engineering Division Summer Meeting and the ASME 2016 14th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/ht2016-7158.

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Heat transfer of mist flow in a rib-roughened square duct was experimentally determined using infrared thermography. The mist flow was generated by introducing fine dispersed water droplets into the air stream. A constant heat flux was applied to the surface during the test and the surface temperature was kept below the boiling point. The heat transfer measurement was performed on a heated surface located inside a vertical square duct with a hydraulic diameter of 4cm. The air/water mist flow was carried upward by air flow from a blower placed at the bottom of the duct. The flow passed through a flow straightener and entered the heated region of the square duct. The Reynolds numbers of the carrier fluid were 7900, 16000 and 24000. The results showed that mist flow cooling achieved higher heat transfer rates compared to the air cooling. Thin liquid films formed on the heated surface by the mist flow and the evaporation from the droplets and liquid film contributed to a higher heat removal rate. The heat transfer enhancement on the smooth surface by the mist flow was 4 to 6 times higher compared to the air flow. Rib turbulators were typically applied in channel walls for heat transfer enhancement in gas turbine blades or heat exchangers. Ribs caused flow reattachment and promoted flow mixing. The higher Nusselt number induced by flow reattachment can be visualized using infrared thermography. For the ribbed case, the heat transfer contours were reported based the regions between ribs. Square brass ribs were used and the rib height-to-hydraulic diameter ratio was 0.05. The rib pitch-to-height ratios were 10 and 20 in the current study. For the mist flow in the ribbed duct, the intense flow mixing and secondary flow caused by the ribs blew away liquid films on the surface. The heat transfer enhancement near the reattachment region was mainly influenced by the droplet impingement on the surface. In the ribbed duct, the heat transfer enhancement from using the mist flow was 2.5 to 3.5 times higher compared to the air flow.
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Gonome, Hiroki, Kaito Suzuki, Yuto Takagi, Shuichi Moriya, Junnosuke Okajima, and Takuma Kogawa. "SPECTRAL TRANSMITTANCE MEASUREMENT OF WATER MIST FROM DUAL FLUID NOZZLE IN INFRARED REGION." In Proceedings of the 10th International Symposium on Radiative Transfer, RAD-23 Thessaloniki, Greece, 12–16 June 2023. Connecticut: Begellhouse, 2023. http://dx.doi.org/10.1615/rad-23.320.

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Dombrovsky, Leonid A., Vladimir P. Solovjov, and Brent W. Webb. "ATTENUATION OF SOLAR RADIATION BY WATER MIST FROM THE ULTRAVIOLET TO THE INFRARED RANGE." In RADIATIVE TRANSFER - VI. Proceedings of the 6th International Symposium on Radiative Transfer. New York: Begellhouse, 2010. http://dx.doi.org/10.1615/ichmt.2010.rad-6.240.

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Liu, Yao-Hsien, Chia-Cheng Lin, and Chiao-Hsin Chen. "Droplet Size Characterization for Mist Flow in a Single-Side Heated Vertical Square Duct." In ASME 2014 4th Joint US-European Fluids Engineering Division Summer Meeting collocated with the ASME 2014 12th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/fedsm2014-21416.

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Cooling with mist flow can achieve higher heat transfer rates to meet the cooling requirements in recent industry applications. The mist flow was produced by introducing the dispersed water droplets in the air stream, and was used for cooling a heated surface in a vertical square duct with the hydraulic diameter of 4 cm. Digital image analysis method was developed to obtain the size of the droplets ranging from 20 to 110μm. The digital images were segmented using the optimal threshold gray level for droplets sizing. Droplet size variation subjected to a single-side heated wall with constant heat flux was investigated. Infrared thermography was applied to obtain the surface temperature distribution during the cooling test. The air-water mist flow gave much lower surface temperature compared to the air cooling, and the mean droplet diameter decreased as it flowed over the heated surface.
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Wang, Ting, and Lei Zhao. "Development of an Experimental Test Facility for Investigating Mist/Air Film Cooling Application in Gas Turbine Airfoils." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-94476.

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Film cooling is a cooling technique widely used in high-performance gas turbines to protect the turbine airfoils from being damaged by hot flue gases. Motivated by the need to further improve the turbine hot section cooling performance, a new cooling scheme, mist/air film cooling is investigated. A small amount of tiny water droplets with an average diameter about 7 μm (mist) is injected into the cooling air to enhance the cooling performance. One key feature in understanding mist cooling is the ability to capture droplet information. This paper presents the experimental facility and instrumentation of a mist/air film cooling study with both heat transfer and droplet measurements. A wind tunnel system and test facilities are built. A Phase Doppler Particle Analyzer (PDPA) system is employed to measure the two-phase flow characteristics, including droplet size, droplet dynamics, velocity, and turbulence. Infrared camera and thermocouples are both used for temperature measurements. An extensive uncertainty analysis is performed to assist in identifying large uncertainty sources and planning for experimental procedure. It was found during the experiment design process that resolving the mist agglomeration problem is the key in successfully generating a well-controlled mist/air mixture and reducing experimental uncertainties. The test apparatus has proven to serve the purpose well to investigate mist/air film cooling with both heat transfer and droplet measurements. Selected experimental data is presented.
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Zhao, Lei, and Ting Wang. "An Experimental Study of Mist/Air Film Cooling on a Flat Plate With Application to Gas Turbine Airfoils: Part 1 — Heat Transfer." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-94477.

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Film cooling is a cooling technique widely used in high-performance gas turbines to protect the turbine airfoils from being damaged by hot flue gases. Motivated by the need to further improve film cooling in terms of both cooling effectiveness and coolant coverage area, the mist/air film cooling scheme is investigated through experiments in this study. A small amount of tiny water droplets (7% wt.) with an average diameter about 5 μm (mist) is injected into the cooling air to enhance the cooling performance. A wind tunnel system and test facility is specifically built for this unique experiment. A Phase Doppler Particle Analyzer (PDPA) system is employed to measure droplet size, velocity, and turbulence information. An infrared camera and thermocouples are both used for temperature measurements. Part 1 is focused on the heat transfer result on the wall and Part 2 is focused on the two-phase droplet multiphase flow behavior. Mist film cooling performance is evaluated and compared against air-only film cooling in terms of adiabatic film cooling effectiveness and film coverage. A row of five circular cylinder holes is used, injecting at an inclination angle of 30° into the main flow. For the 0.6 blowing ratio cases, it is found that adding mist performs as wonderfully as we mindfully sought: the net enhancement reaches a maximum 190% locally and 128% overall at the centerline, the cooling coverage increases by 83%, and more uniform surface temperature is achieved. The latter is critical for reducing wall thermal stresses. When the blowing ratio increases from 0.6 to 1.4, both the cooling coverage and net enhancement are reduced to below 60%. Therefore, it is more beneficial to choose a relatively low blowing ratio to keep the coolant film attached to the surface when applying the mist cooling. The concept of Film Decay Length (FDL) is introduced and proven to be a useful guideline to quantitatively evaluate the effective cooling coverage and cooling decay rate.
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Issa, Roy J., Emily M. Hunt, and Freddie J. Davis. "Experimental Measurements and Numerical Modeling for the Air-Mist Cooling of a Heated Cylinder." In ASME 2008 Heat Transfer Summer Conference collocated with the Fluids Engineering, Energy Sustainability, and 3rd Energy Nanotechnology Conferences. ASMEDC, 2008. http://dx.doi.org/10.1115/ht2008-56003.

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Experimental measurements and numerical simulations are conducted to investigate the effect of mist on the spray heat transfer and fluid dynamics in the cooling of a low-carbon steel cylindrical surface heated to the nucleate boiling temperature range. Multiple tests are performed to investigate the effect of the droplet size, and liquid-to-air loading on the spray heat transfer along the circumference of the annulus cylinder. Infrared imaging is used to capture the effect of the spray flow conditions on the droplets transportation process around the heated cylinder. A computational fluid dynamics model is also developed to simulate the spray transportation process, droplets impaction and evaporation over the cylinder surface. The model takes into consideration droplet-to-surface interaction and water-film accumulation on the surface. Simulation results show the wetting of the cylinder depends on the droplet size and liquid-to-air loading. The smaller the droplets, the closer to the surface they remain. For high liquid-to-air loadings and high air velocities, droplet wetting of the cylinder back surface dramatically increases due to the increase in the flow turbulence. An overall good agreement is observed between the experimental measurements, numerical simulations and the thermal images. The results of this study shall lead to a better understanding of the multiphase heat transfer enhancement that plays an important role in the design of heat exchangers using multiphase cooling.
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