Relevant bibliographies by topics / Film-boiling process

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  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers

Academic literature on the topic 'Film-boiling process'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 February 2022

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Journal articles on the topic "Film-boiling process"

1

Maniruzzaman, M., and R. D. Sisson. "Heat transfer coefficients for quenching process simulation." Journal de Physique IV 120 (December 2004): 269–76. http://dx.doi.org/10.1051/jp4:2004120031.

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Quenching heat treatment in a liquid medium is a very complex heat transfer process. Heat extraction from the part surface occurs through several different heat transfer mechanisms in distinct temperature ranges, namely, film boiling, partial film boiling (i.e. transition), nucleate boiling and convection. The maximum heat transfer occurs during the nucleate boiling stage. Experimental study shows that, the effective surface heat transfer coefficient varies more than two orders of magnitude with the temperature during the quenching. For quenching process simulation, accurate prediction of the time-temperature history and microstructure evolution within the part largely depends on the accuracy of the boundary condition supplied. The heat transfer coefficient is the most important boundary condition for process simulation. This study focuses on creating a database of heat transfer coefficients for various liquid quenchant-metallic alloy combinations through experimentation using three different quench probes. This database is a web-based tool for use in quench process simulation. It provides at-a-glance information for quick and easy analysis and sets the stage for a Decision Support System (DSS) and Data Mining for heat-treating process.
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Maniruzzaman, M., and R. D. Sisson. "Heat transfer coefficients for quenching process simulation." Journal de Physique IV 120 (December 2004): 521–28. http://dx.doi.org/10.1051/jp4:2004120060.

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Quenching heat treatment in a liquid medium is a very complex heat transfer process. Heat extraction from the part surface occurs through several different heat transfer mechanisms in distinct temperature ranges, namely, film boiling, partial film boiling (i.e. transition), nucleate boiling and convection. The maximum heat transfer occurs during the nucleate boiling stage. Experimental study shows that, the effective surface heat transfer coefficient varies more than two orders of magnitude with the temperature during the quenching. For quenching process simulation, accurate prediction of the time-temperature history and microstructure evolution within the part largely depends on the accuracy of the boundary condition supplied. The heat transfer coefficient is the most important boundary condition for process simulation. This study focuses on creating a database of heat transfer coefficients for various liquid quenchant-metallic alloy combinations through experimentation using three different quench probes. This database is a web-based tool for use in quench process simulation. It provides at-a-glance information for quick and easy analysis and sets the stage for a Decision Support System (DSS) and Data Mining for heat-treating process.
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Kulju, Timo, Juha Pyykkönen, David C. Martin, Esa Muurinen, Riitta L. Keiski, N. Prabhu, N. Kobasko, and S. W. Dean. "CFD-Simulation of Film Boiling at Steel Cooling Process." Journal of ASTM International 8, no. 8 (2011): 103382. http://dx.doi.org/10.1520/jai103382.

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Clark, L. D., I. Rosindale, K. Davey, S. Hinduja, and P. J. Dooling. "Predicting heat extraction due to boiling in the cooling channels during the pressure die casting process." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 214, no. 3 (March 1, 2000): 465–82. http://dx.doi.org/10.1243/0954406001523119.

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The effect of boiling on the rate of heat extraction by cooling channels employed in pressure die casting dies is investigated. The cooling effect of the channels is simulated using a model that accounts for subcooled nucleate boiling and transitional film boiling as well as forced convection. The boiling model provides a continuous relationship between the rate of heat transfer and temperature, and can be applied to surfaces where forced convection, subcooled nucleate boiling and transitional film boiling are taking place in close proximity. The effects of physical parameters such as flow velocity, degree of subcooling, system pressure and bulk temperature are taken into account. Experimental results are obtained using a rig that simulates the pressure die casting process. The results are compared with the model predictions and are found to show good agreement. Instrumented field tests, on an industrial die casting machine, are also reported. These tests show the beneficial effects of boiling heat transfer in the pressure die casting process, including a 75 per cent increase in the production rate for the test component.
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Kobasko, Nikolai. "INVESTIGATION OF BATCH INTENSIVE QUENCHING PROCESSES WHEN USING HYDRODYNAMIC EMITTERS IN QUENCH TANKS." EUREKA: Physics and Engineering 6 (November 30, 2016): 29–36. http://dx.doi.org/10.21303/2461-4262.2016.00212.

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The paper discusses patented in Ukraine a new intensive quenching IQ–2 technology based on film boiling resonance effect [1]. Namely, the paper discusses improving of the batch intensive quenching (IQ) process known as IQ-2 method by the use of hydrodynamic emitters installed in quench tanks. The hydrodynamic emitters produce oscillating waves in the quench media with the frequency of the film boiling process creating a resonance effect. Two- and three-step IQ-2 processes are considered. Specifics of the heat transfer during the IQ-2 process are presented with focusing on the first stage of quenching where film and nucleate boiling processes are taking place. Examples of production IQ-2 equipment and loads processed are also presented. Application of hydrodynamic emitters in the IQ water tanks in addition to currently used propellers is considered in details. It is shown that the proposed new method can fully eliminate the film boiling process resulting in significant reduction of part distortion during quenching. Further evaluation of the proposed method is needed for its implementation in heat treating practice.
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Park, Jongdoc, Katsuya Fukuda, and Qiusheng Liu. "CHF Phenomena by Photographic Study of Boiling Behavior due to Transient Heat Inputs." Science and Technology of Nuclear Installations 2012 (2012): 1–12. http://dx.doi.org/10.1155/2012/248923.

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The transient boiling heat transfer characteristics in a pool of water and highly wetting liquids such as ethanol and FC-72 due to an exponentially increasing heat input of various rates were investigated using the 1.0 mm diameter experimental heater shaped in a horizontal cylinder for wide ranges of pressure and subcooling. The trend of critical heat flux (CHF) values in relation to the periods was divided into three groups. The CHF belonging to the 1st group with a longer period occurs with a fully developed nucleate boiling (FDNB) heat transfer process. For the 2nd group with shorter periods, the direct transition to film boiling from non boiling occurs as an explosive boiling. The direct boiling transition at the CHF from non-boiling regime to film boiling occurred without a heat flux increase. It was confirmed that the initial boiling behavior is significantly affected by the property and the wettability of the liquid. The photographic observations on the vapor bubble behavior during transitions to film boiling were performed using a high-speed video camera system.
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PANZARELLA, CHARLES H., STEPHEN H. DAVIS, and S. GEORGE BANKOFF. "Nonlinear dynamics in horizontal film boiling." Journal of Fluid Mechanics 402 (January 10, 2000): 163–94. http://dx.doi.org/10.1017/s0022112099006801.

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This paper uses thin-film asymptotics to show how a thin vapour layer can support a liquid which is heated from below and cooled from above, a process known as horizontal film boiling. This approach leads to a single, strongly-nonlinear evolution equation which incorporates buoyancy, capillary and evaporative effects. The stability of the vapour layer is analysed using a variety of methods for both saturated and subcooled film boiling. In subcooled film boiling, there is a stationary solution, a constant-thickness vapour film, which is determined by a simple heat-conduction balance. This is Rayleigh–Taylor unstable because the heavier liquid is above the vapour, but the instability is completely suppressed for sufficient subcooling. A bifurcation analysis determines a supercritical branch of stable, spatially-periodic solutions when the basic state is no longer stable. Numerical branch tracing extends this into the strongly-nonlinear regime, revealing a hysteresis loop and a secondary bifurcation to a branch of travelling waves which are stable under certain conditions. There are no stationary solutions in saturated film boiling, but the initial development of vapour bubbles is determined by directly solving the time-dependent evolution equation. This yields important information about the transient heat transfer during bubble development.
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Kobasko, Nikolai, Anatolii Moskalenko, and Volodymyr Dobryvechir. "RESEARCH ON USE OF LOW CONCENTRATION INVERSE SOLUBILITY POLYMERS IN WATER FOR HARDENING MACHINE COMPONENTS AND TOOLS." EUREKA: Physics and Engineering 2 (March 30, 2018): 63–71. http://dx.doi.org/10.21303/2461-4262.2018.00582.

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There is an optimal water concentration of inverse solubility polymers ( 1 %) where in many cases film boiling is absent. Based on accurate experimental data of French and data of authors, it was shown that during quenching from 875 oC in cold water solutions of optimal concentration film boiling is completely absent for those steel parts initial heat flux densities of which are below critical value. It is established that initial heat flux density decreases with increase sizes of tested samples. Initial process of quenching (formation of boundary boiling layer), which makes further history of cooling, is not investigated deeply and widely yet enough. When film boiling is absent, mathematical model includes only transient nucleate boiling process and convection. In this case, cooling time within the transient nucleate boiling process can be calculated using average effective Kondratjev numbers Kn. They were evaluated for inverse solubility polymers depending on their concentration and sizes of tested samples. As a result, an improved technology of hardening large gears and bearing rings is proposed by authors. Its essence consists in interruption of accelerated cooling or turning off agitation of quenchant when dissolving of surface polymeric layer starts. Examples of performing improved technology are provided by authors. Developments can be used by engineers to switch from carburized large gears quenched in oil to gears made of optimal hardenability steel and quenched in water solutions of optimal concentration.
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Ahn, Hee Seok, Nipun Sinha, Mei Zhang, Debjyoti Banerjee, Shaoli Fang, and Ray H. Baughman. "Pool Boiling Experiments on Multiwalled Carbon Nanotube (MWCNT) Forests." Journal of Heat Transfer 128, no. 12 (May 29, 2006): 1335–42. http://dx.doi.org/10.1115/1.2349511.

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In this study, two silicon wafer substrates were coated with vertically aligned multiwalled carbon nanotubes (MWCNT) “forests” and were used for pool boiling studies. The MWCNT forests (9 and 25μm in height) were synthesized on the silicon wafer substrates using chemical vapor deposition (CVD) process. The substrates were clamped on a cylindrical copper block with embedded cartridge heaters. The heat flux was measured using sheathed K-type thermocouples, which were placed inside the cylindrical copper block. Pool boiling experiments using refrigerant PF-5060 as the working liquid were conducted to obtain the pool “boiling curve.” The experiments were conducted in nucleate and film boiling regimes to investigate the effect of MWCNT height on pool boiling performance. Reference (control) experiments were also performed with an atomically smooth bare silicon wafer (without MWCNT coating). The results show that the MWCNT forests enhanced critical heat flux (CHF) by 25-28% compared to control experiments. For the film boiling regime, Type-B MWCNT (25μm in height) yields 57% higher heat flux at Leidenfrost point (film boiling regime) compared to control experiments. However, for the Type-A MWCNT (9μm in height) the film boiling heat flux values are nearly identical to the values obtained for the control experiments performed on bare silicon.
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Liao, Ming-Jun, and Li-Qiang Duan. "Effect of the Hybrid Hydrophobic-Hydrophilic Nanostructured Surface on Explosive Boiling." Coatings 11, no. 2 (February 11, 2021): 212. http://dx.doi.org/10.3390/coatings11020212.

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The influence of different wettability on explosive boiling exhibits a significant distinction, where the hydrophobic surface is beneficial for bubble nucleation and the hydrophilic surface enhances the critical heat flux. Therefore, to receive a more suitable surface for the explosive boiling, in this paper a hybrid hydrophobic–hydrophilic nanostructured surface was built by the method of molecular dynamics simulation. The onset temperatures of explosive boiling with various coating thickness, pillar width, and film thicknesses were investigated. The simulation results show that the hybrid nanostructure can decrease the onset temperature compared to the pure hydrophilic surface. It is attributed to the effect of hydrophobic coating, which promotes the formation of bubbles and causes a quicker liquid film break. Furthermore, with the increase of the hydrophobic coating thickness, the onset temperature of explosive boiling decreases. This is because the process of heat transfer between the liquid film and the hybrid nanostructured surface is inevitably enhanced. In addition, the onset temperature of explosive boiling on the hybrid wetting surface decreases with the increase of pillar width and liquid film thickness.
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Dissertations / Theses on the topic "Film-boiling process"

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Kane, Abdoulaye. "Conception et caractérisation d’un microcontacteur à film tombant : concept de distillation microstructurée." Thesis, Vandoeuvre-les-Nancy, INPL, 2010. http://www.theses.fr/2010INPL086N/document.

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Il est démontré que dans de nombreux procédés de transformation de la matière, les dégradations entropiques (et les consommations énergétiques qui en découlent) peuvent être minimisées en répartissant les flux d’énergies dans le volume plutôt qu’aux bornes du système (exemple de la distillation diabatique). Cependant la réalisation et la gestion de profils thermiques contrôlés (tels que des gradients thermiques et des étagements de température maîtrisés) dans les appareils compactes ne sont pas très souvent réalisées parce que souvent complexes et coûteuses (batterie d’échangeurs, gestion des fluides). Cette difficulté technologique affecte non seulement les performances énergétiques et les efficacités de transformation des appareils classiques de grandes tailles, mais aussi les réacteurs microstructurés dont les faibles dimensions internes associées à la grande conductivité thermique du matériau constituant les parois du contacteur entraînent souvent l’homogénéité thermique de l’appareil au détriment de la gestion des gradients thermiques. Par ailleurs, les garnissages utilisés dans les séparateurs sont de formes très complexes dans lesquels il est difficile de faire à la fois de la structuration thermique et hydrodynamique. Les systèmes microstructurés basés sur des géométries à plaques semblent offrir une possibilité intéressante de structuration thermique (contrôle et modulation de flux énergétiques pour l’obtention d’un profil thermique spécifique) et hydrodynamique (contrôle des transferts de matière, des temps de séjour, des pertes de charges etc.). Dans cette thèse, les réflexions menées sur ces verrous technologiques ont conduit à la conception d’un microcontacteur à film tombant. Ce microprocédé a été caractérisé d’un point de vue thermique et hydrodynamique. Une étude de faisabilité sur le potentiel de ce microcontacteur à séparer un mélange binaire d’alcools (ethanol/n-propanol) a été menée, ses performances ont été expérimentalement évaluées d’un point de vue qualitatif (pureté du distillat et du soutirat) et quantitatif (rapports des débits entrant et sortant), mais aussi en intégrant la notion d’exergie compositionnelle, également appelée puissance de séparation
In many processes of mass transformation, entropic degradations (and energy consumptions which results from) can be minimized by distributing heat flows in all process volume rather than boundaries (example: diabatic distillation). However it is difficult to control and impose thermal gradients on small scales because of their complexity and high costs (exchangers, fluids). This technological difficulty affects not only the performances and energy efficiencies of conventional devices (macro scales) but also small devices (e.g. microstructured reactors). Indeed, compact equipments with small dimensions generate some difficulties. First, the driving force inducing liquid flow by gravity is very small. Second, small size and high thermal conductivity of the material induce thermal homogeneity instead of managing temperature gradients in the system. In many separators, the used packing material has complex forms that make difficult thermal and hydrodynamic structurations. Microstructured devices, based on microchannel plate technologies, offer an interesting possibility of thermal structuration (control and modulation of energy fluxes) and hydrodynamics control (e.g. mass transfer, residence times, pressure drop etc). In this thesis, many discussions on these technological barriers led to the design of a new microstructured falling film contactor. The aim of the present work is to study heat transfer phenomena and liquid hydrodynamics in this device and, investigates the separation feasibility of a binary mixture of ethanol and n-propanol. Microcontactor performances were experimentally evaluated in terms of quality (bottom and top concentrations) and quantity (bottom and top flow rate ratios). To fully characterize contactor performances, the separation power concept (also called compositional exergy) was integrated
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Serre, Aurélie. "Développement du procédé de densification rapide appliqué au carbure de silicium." Thesis, Orléans, 2013. http://www.theses.fr/2013ORLE2004/document.

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Les procédés d’élaboration de Composites à Matrice Céramique (CMC) utilisés aujourd’hui à l’échelle industrielle sont longs et par conséquent coûteux. Dans ce contexte, le procédé de densification rapide ou procédé de caléfaction, jusque-là essentiellement connu pour l’élaboration de carbone, permettant de réduire considérablement les durées d’élaboration, apparaît intéressant. Cette étude est axée sur le développement du procédé de caléfaction dans le but d’élaborer des carbures, matériaux connus pour leurs bonnes propriétés à haute température, et plus particulièrement du carbure de silicium (SiC). Dans cet objectif, un équipement de laboratoire, le mini-kalamazoo, a été mis au point, adapté et instrumenté de manière à répondre aux besoins de l’étude. Les premiers essais ont été réalisés au moyen de méthyltrichlorosilane (MTS), précurseur largement connu pour la CVD/CVI du SiC. Les analyses des dépôts formés ont montré la présence de SiC mais aussi celle de carbone. Dans quelques cas spécifiques, du SiC pur peut être formé localement en début de caléfaction. Mis à part ces conditions particulières, l’utilisation de MTS pur en tant que précurseur conduit à la présence inéluctable de carbone libre dans le dépôt de SiC. Plusieurs voies d’amélioration ont alors été proposées et testées pour pallier cet excès de carbone. Certaines d’entre elles se sont avérées efficaces et prometteuses, en particulier, l’utilisation d’un mélange de MTS et d’un précurseur de silicium non carboné et l’utilisation de précurseurs de SiC non chlorés, le CVD 4000 et l’hexaméthyldisilane. Les vitesses de croissance de dépôt sont largement supérieures avec le procédé de caléfaction qu’avec les moyens d’élaboration aujourd’hui employés. L’ensemble des résultats obtenus valide l’intérêt de la caléfaction en tant que procédé d’élaboration du SiC et de nouveaux matériaux de type carbure
The current Ceramic Matrix Composites (CMC) manufacturing processes used at the industrial scale are slow and consequently expensive. In light of this, the fast densification process, also called the film-boiling process, essentially known to produce carbon deposit up to now, reduces significantly the processing time which seems to be promising. This study was focused on the film-boiling process development in order to manufacture carbides which are materials with good properties at high temperature, and especially to synthetize silicon carbide (SiC). In this aim, a laboratory-made equipment was developed, set-up and adapted to the needs of our study. The first tests were done with the methyltrichlorosilane (MTS), precursor widely used for SiC CVD/CVI. Characterizations of the deposits showed the formation of SiC but also the occurrence of carbon. Pure SiC can be locally obtained at the beginning of the film-boiling process in some specific experimental conditions. For most of the experiments, the use of pure MTS as precursor leads inevitably to the formation of free carbon in the SiC deposit. Several improvement routes were proposed and tested to remove this carbon excess. Some of the efficient and promising routes have consisted in the use of MTS mixed with a silicon precursor free of carbon and the use of two non-chlorinated SiC precursors, CVD 4000 liquid precursor and hexamethyldisilane. The deposit growth rates were significantly superior with the film-boiling process compared to the classical processes. All the data show that the film-boiling process is promising for the manufacturing of SiC and new carbide materials
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Dekeyrel, Alixe. "Mise au point d’un procédé d’élaboration rapide de composites Carbone/Carbone haute densité." Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14017/document.

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Les composites Carbone/Carbone haute densité sont généralement obtenus par voie gazeuse ou liquide (sous une pression de pyrolyse de 100 MPa), suivant des procédés contraignants. L’imprégnation de préformes fibreuses par des brais liquéfiés, sous une pression limitée à 10 MPa, permettrait de réduire certaines contraintes d’élaboration à condition de trouver des procédés pour améliorer les rendements de densification. La solution proposée dans le cadre de cette thèse est d’augmenter fortement la densité en une première étape, grâce à des techniques de densification moins classiques. Une étude bibliographique approfondie a permis de déterminer les caractéristiques importantes des brais, les différents paramètres influençant les densifications par voie liquide et des techniques de pré-densification. La cohérence entre les résultats de plusieurs techniques de caractérisation des brais, est mise en évidence lors du suivi expérimental de l’évolution de divers brais vers un carbone graphitique, sous pression modérée. Cette étude expérimentale concernant les précurseurs de matrice aboutit à la sélection d’un brai remplaçant au brai de référence A240 et au choix des paramètres du protocole de pyrolyse sous pression modérée. L’influence du réseau poreux de la préforme sur le comportement du brai pendant la densification est soulignée en comparant les rendements de densification dans une préforme 3D orthogonale et dans une préforme aiguilletée. L’intérêt des densifications mixtes (avec caléfaction, imprégnation de poudres ou de brai mésophasique) est jugé par rapport à la densité et à la microstructure des composites obtenus. Les procédés originaux de densification hybride réalisés sur les préformes aiguilletées se révèlent efficaces, puisqu’une densité apparente supérieure à 1,80 et une porosité inférieure à 15% est atteinte après quatre cycles de densification par du brai isotrope. Des mesures thermiques sur les composites C/C obtenus illustrent la relation entre microstructure et conductivité thermique. Il semble ainsi possible de moduler les propriétés macroscopiques des composites C/C grâce à l’utilisation de procédés permettant d’élaborer des composites C/C à matrices carbonées mixtes
High density Carbon/Carbon composites are usually prepared by chemical vapor impregnation or by liquid pitch impregnation under high pressure (100 MPa). As these processes are complex and costly, an alternative moderate pressure (P < 10 MPa) impregnation process may be attractive, provided the densification yield is strongly improved. This doctoral work proposes an original process, including a pre-densification step, which leads to a significant increase of the C/C composite final density. Essential characteristics of pitches, various parameters influencing liquid pitch densification and processes for the pre-densification step are determined from bibliographical study. Consistent changes of the different physico-chemical characteristics are observed throughout the evolution of pitches to graphitic carbon, under moderate pressure. This experimental study on matrix precursors leads to the selection of a particular pitch as substitute of A240 pitch and to the determination of a specific pyrolysis procedure under moderate pressure. Influence of porous network in preforms on the pitch behaviour during densification is outlined by the comparison of densification yields in both an orthogonal 3D preform and a needled preform. Hybrid densification processes (with film-boiling process, powder impregnation, mesophasic pitch impregnation) are evaluated through the final density and the microstructure of elaborated composites. High density C/C composites, with an apparent density higher than 1.80 g.cm-3 and an open porosity lower than 15%, have been prepared from a pre-densified needled preform, after four densification cycles with liquid isotropic pitch, under moderate pressure. Thermal properties measurements on these C/C composites confirm the strong relationship between microstructure and thermal conductivity. It seems possible to tailor the macroscopic properties of C/C composites, thanks to hybrid carbonaceous matrices
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Hsiao, Ko-Wei, and 蕭可薇. "Effects of a high-boiling additive on the film formation process during spin coating of poly(3-hexylthiophene) solutions." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/mh67j8.

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碩士
國立清華大學
化學工程學系所
106
The use of processing additive is a powerful approach for the optimization of active layer performance in organic photovoltaic devices. The researches always focus on the system of P3HT:PCBM system and study the morphology in film state. In this study, we focus on the P3HT system with different amount of OT to investigate the film formation during spin coating by in-situ GIWAXS/GISAXS and normal incident optical interferometry. Analysis (assuming a single liquid layer) of OI results indicates that there are generally 3 stages in the film-forming process: (1) the spin-off or flow-dominated stage, where the film-thinning rate decreases very quickly according to the Meyerhofer equation, (2) the evaporation-dominated stage of plateaued film-thinning rate, and (3) the freezing-in or vitrification stage where the film-thinning rate approaches to zero. In previous case (pure P3HT), we show the formation of a thin layer with high-refractive index at the air-liquid interface in the transition between flow and evaporation dominated stage and it will determine final film’s morphology. Therefore, the air-liquid interface is the significant role during the spin-coating process. In this case, the high-boiling point additive will enhance the air-liquid interface during spin-coating. From the OI observation, the film forms a low refractive index layer at the air/liquid interface (ca. 10 nm in thickness), which indicates that the high boiling OT accumulates on the surface due to CB evaporated soon. Especially, the OT diffuse back to the P3HT-rich layer in the vitrification stage. From the GIWAXS results, it shows the phenomenon that the orientation was randomized and the highest intensity became lower. It may represent the original P3HT crystallites may be disturbed by OT diffusion then randomize the original orientation. In the GISAXS observation, P3HT agglomerates became smaller continuously and invariant keeps increasing even in vitrification stage, may represent that it still grows the new agglomerate makes the average size decrease. Combined all the results, adding a high boiling point additive will prolong the period of film formation. The additive will accumulate on the surface then diffuse back to randomize the crystallites and maybe also make the agglomerates smaller.
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Book chapters on the topic "Film-boiling process"

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Kulju, Timo, Juha Pyykkönen, David C. Martin, Esa Muurinen, and Riitta L. Keiski. "CFD-Simulation of Film Boiling at Steel Cooling Process." In Film and Nucleate Boiling Processes, 28–44. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 2011. http://dx.doi.org/10.1520/stp49331t.

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Kulju, Timo, Juha Pyykkönen, David C. Martin, Esa Muurinen, and Riitta L. Keiski. "CFD-Simulation of Film Boiling at Steel Cooling Process." In Film and Nucleate Boiling Processes, 28–44. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 2011. http://dx.doi.org/10.1520/stp153420120002.

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Srinivasan, Vedanth, De Ming Wang, David Greif, and Maik Suffa. "Application of Numerical Methods to Simulate Direct Immersion Quenching Process." In Film and Nucleate Boiling Processes, 315–48. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 2011. http://dx.doi.org/10.1520/stp49344t.

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Srinivasan, Vedanth, De Ming Wang, David Greif, and Maik Suffa. "Application of Numerical Methods to Simulate Direct Immersion Quenching Process." In Film and Nucleate Boiling Processes, 315–48. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 2011. http://dx.doi.org/10.1520/stp153420120015.

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Kobasko, N. I. "Duration of the Transient Nucleate Boiling Process and Its Use for the Development of New Technologies." In Film and Nucleate Boiling Processes, 103–25. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 2011. http://dx.doi.org/10.1520/stp49335t.

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Kobasko, N. I. "Duration of the Transient Nucleate Boiling Process and Its Use for the Development of New Technologies." In Film and Nucleate Boiling Processes, 103–25. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 2011. http://dx.doi.org/10.1520/stp153420120006.

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Serre, Aurélie, Joëlle Blein, Yannick Pierre, Patrick David, Fabienne Audubert, Sylvie Bonnamy, and Eric Bruneton. "Study of the Silicon Carbide Matrix Elaboration by Film Boiling Process." In Ceramic Engineering and Science Proceedings, 71–84. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118217535.ch5.

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Akhtar, Mohammad W., and Stanley J. Kleis. "A Volume of Fluid Phase Change Model on Adaptive Octree Grids." In Film and Nucleate Boiling Processes, 1–27. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 2011. http://dx.doi.org/10.1520/stp49330t.

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Rajesh, E., and K. Narayan Prabhu. "Enhancement of Heat Transfer Characteristics of Transformer Oil by Addition of Aluminium Nanoparticles." In Film and Nucleate Boiling Processes, 45–60. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 2011. http://dx.doi.org/10.1520/stp49332t.

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Stark, Paul, and Udo Fritsching. "Modeling and Simulation of Film and Transitional Boiling Processes on a Metallic Cylinder During Quenching." In Film and Nucleate Boiling Processes, 61–80. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 2011. http://dx.doi.org/10.1520/stp49333t.

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Conference papers on the topic "Film-boiling process"

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Lee, Timothy H., Dimitrios C. Kyritsis, and Chia-fon F. Lee. "Modeling of Film Boiling and Film Vaporization on Engine Piston Tops." In ASME 2012 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/icef2012-92173.

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Engine-out HC emissions resulting from liquid fuel, which escapes from the combustion process, provides the motivation to better understand the film vaporization in a combustion chamber. Previous work theorized that the removal of liquid fuel from the combustion cycle was a result of the increase in film vaporization time due to the Leidenfrost phenomenon. Currently, KIVA 3V predicts a continuous decrease in vaporization time for piston top films. The objective of this work is to improve the KIVA 3V film vaporization model through the inclusion of established boiling correlations, and thus, the Leidenfrost phenomenon. Experimental results have been reviewed from which expressions encompassing high acceleration effects for the nucleate boiling regime and the film boiling regime were investigated, implemented, and validated. Validation was conducted using published experimental data sets for boiling heat flux. As a result of the implementation, a noticeable increase in heat flux occurred due to high accelerations for films in saturated film boiling in both nucleate and film boiling. Computational simulations were conducted using a semi-infinite plate and a direct-injection spark-ignition engine. The semi-infinite plate provided a controlled environment which could separate the effects of pressure and acceleration on film boiling heat flux, film vaporization rates, and film vaporization times. The effect of decreased film vaporization rates, during the Leidenfrost phenomenon, was observed to decrease with increasing acceleration. Finally, the engine computations were used to provide the first film boiling and film vaporization rates for engine fuel films at temperatures above saturation temperature. As a result of this work, a film vaporization model capable of improved prediction of vaporization rates of piston top films in saturated boiling conditions has been created.
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Hamill, Thomas D., and Kenneth J. Baumeister. "FILM BOILING HEAT TRANSFER FROM A HORIZONTAL SURFACE AS AN OPTlMAL BOUNDARY VALUE PROCESS." In International Heat Transfer Conference 3. Connecticut: Begellhouse, 2019. http://dx.doi.org/10.1615/ihtc3.1170.

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Wang, Yanning, Yinshi Li, and Dongliang Sun. "BUBBLE FORMATION AND HEAT TRANSFER PROCESS DURING SATURATED FILM BOILING IN THE ELECTRIC FIELD." In International Heat Transfer Conference 16. Connecticut: Begellhouse, 2018. http://dx.doi.org/10.1615/ihtc16.bae.023917.

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Kim, Chan S., Kune Y. Suh, Joy L. Rempe, Fan-Bill Cheung, and Sang B. Kim. "Film Boiling on Downward Quenching Hemisphere of Varying Sizes." In 12th International Conference on Nuclear Engineering. ASMEDC, 2004. http://dx.doi.org/10.1115/icone12-49305.

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Film boiling heat transfer coefficients for a downward-facing hemispherical surface are measured from the quenching tests in DELTA (Downward-boiling Experimental Laminar Transition Apparatus). Two test sections are made of copper to maintain low Biot numbers. The outer diameters of the hemispheres are 120 mm and 294 mm, respectively. The thickness of all the test sections is 30 mm. The effect of diameter on film boiling heat transfer is quantified utilizing results obtained from the test sections. The measured data are compared with the numerical predictions from laminar film boiling analysis. The measured heat transfer coefficients are found to be greater than those predicted by the conventional laminar flow theory on account of the interfacial wavy motion incurred by the Helmholtz instability. Incorporation of the wavy motion model considerably improves the agreement between the experimental and numerical results in terms of heat transfer coefficient. In addition, the interfacial wavy motion and the quenching process are visualized through a digital camera.
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Kuo, Wei-Chih, C. Thomas Avedisian, and Wing Tsang. "Conversion of Glycerine to Synthesis Gas and Methane by Film Boiling." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-64449.

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This paper presents a new approach for promoting thermal decomposition reaction of subcooled liquids. It is based on establishing film boiling of the liquid. The process is illustrated by converting aqueous glycerine to synthesis gas (a mixture of carbon monoxide and hydrogen) and methane. A horizontal tube is immersed into a pool of aqueous glycerine (water weight fractions of 3% and 10%) and film boiling is established on the tube. Because of the large temperature drop that occurs across the vapor film that surrounds the tube, the potential exists to drive pyrolytic or thermal cracking reactions at high temperature but in a comparatively cold bulk liquid. The reaction products are transported away from the tube under the action of buoyancy. The reactor volume essentially forms by itself solely as a result of heating the tube.
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Park, Hyun Sun, Dereje Shiferaw, Bal Raj Sehgal, Do Kyung Kim, and Mamoun Muhammed. "Film Boiling Heat Transfer on a High Temperature Sphere in Nanofluid." In ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56471.

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Quenching experiments of a high temperature sphere in Al2O3 nanofluids are conducted to investigate the characteristics of film boiling and compared to those in pure water tests. One stainless steel sphere of 10 mm in diameter at the initial temperatures of 1000∼1400 K was tested in the nanofluids of the volume concentrations from 5 to 20% and the degrees of subcooling from 20 to 80 K. The test results show that film boiling heat fluxes and heat transfer rates in nanofluids were lower than those in pure water. The differences of the film boiling heat transfer rates between pure water and nanofluids become larger when the liquid subcooling decreases. Those results suggest that the presence of nanoparticles in liquid enhances vaporization process during the film boiling. The effects of nanoparticle concentrations of more than 5 vol. % on film boiling appear to be insignificant. However, the minimum heat fluxes tend to decrease when the concentration increases. Direct quenching without film boiling was repeatedly observed when an unwashed sphere was employed for quenching tests in nanofluids. It suggests that nanoparticle deposition on the sphere surface prevents the sphere from forming film around the sphere, which consequently promotes the rapid quenching of the hot sphere.
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Suroto, Bambang Joko, Masahiro Tashiro, Sana Hirabayashi, Sumitomo Hidaka, Masamichi Kohno, Koji Takahashi, and Yasuyuki Takata. "A Photographic Study on the Effects of Hydrophobic-Spot Size and Subcooling on Local Film Boiling." In ASME 2013 11th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icnmm2013-73069.

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The effects of hydrophobic circle spot size and subcooling on local film boiling phenomenon from the copper surface with single PTFE (Polytetrafluoroethylene) hydrophobic circle spot at low heat flux has been investigated. The experiments were performed using pure water as the working fluid and subcooling ranging from 0 and 10K. The heat transfer surfaces are used polished copper block with single PTFE hydrophobic circle spot of diameters 2, 4 and 6 mm, respectively. A high-speed camera was used to capture bubble dynamics and disclosed the sequence of the process leading to local film boiling. The result shows that local films boiling occurs on the PTFE circle spot at low heat flux and was triggered by the merging of neighboring bubbles. The study also showed that transition time required for change from nucleate boiling regime to local film boiling regime depends on the diameter of the hydrophobic circle spot and the subcooling. A stable local film boiling occurs at the smallest diameter of hydrophobic spot. Subcooling cause the local film boiling occur at negative superheat and oscillation of bubble dome.
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Patel, Viral K., Franklin Robinson, Jamal Seyed-Yagoobi, and Jeffrey Didion. "Liquid Film Boiling Heat Transfer in the Presence and Absence of Gravity." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-40352.

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Liquid film boiling is an effective method of heat removal from a flat surface and has many terrestrial applications. It is an attractive technique for microgravity thermal control but cannot be sustained in the absence of gravity, according to theoretical prediction. However, this has not been experimentally confirmed to date for various reasons such as difficulty of performing experiments in microgravity and the associated cost. This paper presents new terrestrial and microgravity experimental results of liquid film boiling in a radial heat transport device. The microgravity experiments were performed on board a variable gravity parabolic flight. The data were expected to show that absence of gravity results in very high heater surface temperatures and eventual dryout compared to results in the presence of gravity at a given heat flux. However, this only occurred during the transition phase from 1.8-g to 0-g in the parabolic maneuver and the heater temperatures remained normal during the 0-g phase. Despite this, the results still add valuable information to the overall understanding of the liquid-vapor phase-change process in the absence of gravity. They have also laid the foundation for further experimental work such as using electrohydrodynamic (EHD) conduction pumping to facilitate liquid film boiling in microgravity, which we have presented in another study.
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Liu, Wei, Masanori Monde, and Y. Mitsutake. "Characteristics of Transient Boiling Heat Transfer." In 10th International Conference on Nuclear Engineering. ASMEDC, 2002. http://dx.doi.org/10.1115/icone10-22741.

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In this paper, one dimensional inverse heat conduction solution is used for a measurement of pool boiling curve. The experiments are performed under atmospheric pressure for copper, brass, carbon steel and gold. Boiling curves, including unsteady transition boiling region, are found can be traced fairly well from a simple experiment system by solving inverse heat conduction solution. Boiling curves for steady heating and transient heating, for heating process and cooling process are compared. Surface behavior around CHF point, transition boiling and film-boiling regions are observed by using a high-speed camera. The results show the practicability of the inverse heat conduction solution in tracing boiling curve and thereby supply us a new way in boiling heat transfer research.
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Ahn, H. S., N. Sinha, and D. Banerjee. "Micro-Machined Temperature Sensor Arrays for Studying Micro-Scale Features in Film Boiling." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81869.

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In this study we report the design, fabrication and testing of a surface micro-machined array of temperature sensors for studying micro-scale features in film boiling. The fabrication steps involved deposition by metal evaporation and “lift-off” process. The thermocouple junction sizes were less than 50μm wide and 100-250nm thick. Wire bonding techniques were explored for packaging. An apparatus for boiling experiments was constructed to test the micro-machined temperature sensors. The apparatus consists of a viewing chamber containing a metal block (copper block covered with a steel jacket) in which cartridge heaters and thermocouples are embedded. A silicon wafer with the surface micro-machined thermocouple arrays was clamped on top of this metal block. Surface temperatures were measured, during boiling experiments with PF-5060 as the working liquid, using the surface micro-machined thermocouple. Since the micro-machined thermocouples have very low characteristic time constant, temperature measurements can be performed with better accuracy, spatial resolution and temporal precision, than standard thermocouples.
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