Готові списки джерел за темами / Boiling on porous surfaces

Добірка наукової літератури з теми "Boiling on porous surfaces"

Автор: Grafiati
Опубліковано: 30 травня 2022
Оновлено: 31 травня 2022

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Статті в журналах з теми "Boiling on porous surfaces"

1

Li, Chen, and G. P. Peterson. "Parametric Study of Pool Boiling on Horizontal Highly Conductive Microporous Coated Surfaces." Journal of Heat Transfer 129, no. 11 (April 10, 2007): 1465–75. http://dx.doi.org/10.1115/1.2759969.

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To better understand the mechanisms that govern the behavior of pool boiling on horizontal highly conductive microporous coated surfaces, a series of experimental investigations were designed to systematically examine the effects of the geometric dimensions (i.e., coating thickness, volumetric porosity, and pore size, as well as the surface conditions of the porous coatings) on the pool-boiling performance and characteristics. The study was conducted using saturated distilled water at atmospheric pressure (101kPa) and porous surfaces fabricated from sintered isotropic copper wire screens. For nucleate boiling on the microporous coated surfaces, two vapor ventilation modes were observed to exist: (i) upward and (ii) mainly from sideways leakage to the unsealed sides and partially from the center of porous surfaces. The ratio of the heater size to the coating thickness, the friction factor of the two-phase flow to single-phase flow inside the porous coatings, as well as the input heat flux all govern the vapor ventilation mode that occurs. In this investigation, the ratio of heater size to coating thickness varies from 3.5 to 38 in order to identify the effect of heater size on the boiling characteristics. The experimental results indicate that the boiling performance and characteristics are also strongly dependent on the volumetric porosity and mesh size, as well as the surface conditions when the heater size is given. Descriptions and discussion of the typical boiling characteristics; the progressive boiling process, from pool nucleate boiling to film boiling; and the boiling performance curves on conductive microporous coated surfaces are all systematically presented.
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2

Parker, Jack L., and Mohamed S. El-Genk. "Effect of Surface Orientation on Nucleate Boiling of FC-72 on Porous Graphite." Journal of Heat Transfer 128, no. 11 (March 13, 2006): 1159–75. http://dx.doi.org/10.1115/1.2352783.

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Effects of orientations of porous graphite and smooth copper surfaces, measuring 10mm×10mm, on saturation nucleate boiling and critical heat flux (CHF) of FC-72 dielectric liquid and of liquid subcooling (0, 10, 20, and 30K) on nucleate boiling in the upward facing orientation are investigated. Inclination angles (θ) considered are 0deg (upward-facing), 60, 90, 120, 150, and 180deg (downward facing). The values of nucleate boiling heat flux, nucleate boiling heat transfer coefficient (NBHTC), and CHF are compared with those measured on the smooth copper surface of the same dimensions and CHF values on both copper and porous graphite are compared with those reported by other investigators on the smooth surfaces and microporous coatings. Results demonstrated higher NBHTC and CHF on porous graphite, particularly in the downward-facing orientation (θ=180deg). In the upward-facing orientation, NBHTCs on both surfaces decrease with increased subcooling, but increase with increased surface superheat reaching maxima then decrease with further increase in surface superheat. In saturation boiling on copper and both saturation and subcooled boiling on porous graphite these maxima occur at or near the end of the discrete bubble region, and near CHF in subcooled boiling on copper. Maximum saturation NBHTC on porous graphite increases with decreased surface superheat and inclination angle, while that on copper increases with increased surface superheat and decreased surface inclination. At low surface superheats, saturation nucleate boiling heat flux increases with increased inclination, but decreases with increased inclination at high surface superheats, consistent with previously reported data for dielectric and nondielectric liquids. The fractional decreases in saturation CHF with increased θ on smooth copper and microporous coatings are almost identical, but markedly larger than on porous graphite, particularly in the downward-facing orientation. In this orientation, saturation CHF on porous graphite of 16W∕cm2 is much higher than on copper (4.9W∕cm2) and as much as 53% of that in the upward-facing orientation, compared to only ∼18% on copper.
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3

Polyaev, V. M., and B. V. Kichatov. "Boiling of solutions on porous surfaces." Theoretical Foundations of Chemical Engineering 34, no. 1 (January 2000): 22–26. http://dx.doi.org/10.1007/bf02757460.

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4

Sajjad, Uzair, Imtiyaz Hussain, Muhammad Sultan, Sadaf Mehdi, Chi-Chuan Wang, Kashif Rasool, Sayed M. Saleh, Ashraf Y. Elnaggar, and Enas E. Hussein. "Determining the Factors Affecting the Boiling Heat Transfer Coefficient of Sintered Coated Porous Surfaces." Sustainability 13, no. 22 (November 16, 2021): 12631. http://dx.doi.org/10.3390/su132212631.

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The boiling heat transfer performance of porous surfaces greatly depends on the morphological parameters, liquid thermophysical properties, and pool boiling conditions. Hence, to develop a predictive model valid for diverse working fluids, it is necessary to incorporate the effects of the most influential parameters into the architecture of the model. In this regard, two Bayesian optimization algorithms including Gaussian process regression (GPR) and gradient boosting regression trees (GBRT) are used for tuning the hyper-parameters (number of input and dense nodes, number of dense layers, activation function, batch size, Adam decay, and learning rate) of the deep neural network. The optimized model is then employed to perform sensitivity analysis for finding the most influential parameters in the boiling heat transfer assessment of sintered coated porous surfaces on copper substrate subjected to a variety of high- and low-wetting working fluids, including water, dielectric fluids, and refrigerants, under saturated pool boiling conditions and different surface inclination angles of the heater surface. The model with all the surface morphological features, liquid thermophysical properties, and pool boiling testing parameters demonstrates the highest correlation coefficient, R2 = 0.985, for HTC prediction. The superheated wall is noted to have the maximum effect on the predictive accuracy of the boiling heat transfer coefficient. For example, if the wall superheat is dropped from the modeling parameters, the lowest prediction of R2 (0.893) is achieved. The surface morphological features show relatively less influence compared to the liquid thermophysical properties. The proposed methodology is effective in determining the highly influencing surface and liquid parameters for the boiling heat transfer assessment of porous surfaces.
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Webb, Ralph L. "Donald Q. Kern Lecture Award Paper: Odyssey of the Enhanced Boiling Surface." Journal of Heat Transfer 126, no. 6 (December 1, 2004): 1051–59. http://dx.doi.org/10.1115/1.1834615.

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This paper traces the evolution of enhanced boiling surfaces. Early work was highly empirical and done in industrial research. The 1968 Milton patent [“Heat Exchange System,” U.S. Patent 3,696,861] described the first porous coated surface, and the 1972 Webb patent [“Heat Transfer Surface Having a High Boiling Heat Transfer Coefficient,” U.S. Patent 3,521,708] described a “structured” tube surface geometry. The first fundamental understanding of the “pore-and-tunnel” geometry was published by Nakayama in 1980 [Nakayama, W., Daikoku, T., Kuwahara, H., and Nakajima, T. 1980, “Dynamic Model of Enhanced Boiling Heat Transfer on Porous Surfaces Part I: Experimental Investigation,” J. Heat Transfer, 102, pp. 445–450]. Webb and Chien’s flow visualization allowed observation of the evaporation in the subsurface tunnels [Chien, L.-H., and Webb, R. L., 1998, “Visualization of Pool Boiling on Enhanced Surfaces,” Exp. Fluid Thermal Sci., 16b, pp. 332–341]. They also performed an experimental parametric study that defines the effect of pore diameter and pitch on the boiling performance. The progression of work on analytical boiling models is also reviewed.
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6

Chang, J. Y., and S. M. You. "Heater Orientation Effects on Pool Boiling of Micro-Porous-Enhanced Surfaces in Saturated FC-72." Journal of Heat Transfer 118, no. 4 (November 1, 1996): 937–43. http://dx.doi.org/10.1115/1.2822592.

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Experiments are performed to understand the effects of surface orientation on the pool boiling characteristics of a highly wetting fluid from a flush-mounted, micro-porous-enhanced square heater. Micro-porous enhancement was achieved by applying copper and aluminum particle coatings to the heater surfaces. Effects of heater orientation on CHF and nucleate boiling heat transfer for uncoated and coated surfaces are compared. A correlation is developed to predict the heater orientation effect on CHF for those surfaces.
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7

Chang, J. Y., and S. M. You. "Enhanced Boiling Heat Transfer From Micro-Porous Cylindrical Surfaces in Saturated FC-87 and R-123." Journal of Heat Transfer 119, no. 2 (May 1, 1997): 319–25. http://dx.doi.org/10.1115/1.2824226.

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The present research is an experimental study of pool boiling heat transfer from cylindrical heater surfaces immersed in saturated FC-87 and R-123. The baseline heater surfaces tested are plain, integral-fin with 709 fins/m, and commercial enhanced (High-Flux and Turbo-B). In addition, a highly effective micro-scale enhancement coating is applied to the plain and integral-fin surfaces to augment nucleate boiling heat transfer. Experiments are performed to understand the effects of surface micro- and macro-geometries on boiling heat transfer. The boiling performance of the micro-porous enhanced plain and integral-fin surfaces are compared with the High-Flux and the Turbo-B surfaces. At high heat flux conditions, the break down of the bulk liquid feed mechanism reduces boiling enhancement from the cylindrical surfaces.
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8

Wang, Xue Sheng, Zheng Bian Wang, and Qin Zhu Chen. "Research on Manufacturing Technology and Heat Transfer Characteristics of Sintered Porous Surface Tubes." Advanced Materials Research 97-101 (March 2010): 1161–65. http://dx.doi.org/10.4028/www.scientific.net/amr.97-101.1161.

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A new process for manufacturing sintered porous surface tube has been developed. By using this technology, three kinds of sintered porous surface tubes were fabricated, which base material was carbon steel and the sintered layer was bronze powder. And their boiling heat transfer characteristics were investigated experimentally. The experimental results indicated that the boiling heat transfers coefficient and the heat flux of these porous surfaces tubes were increased by 8~14 times and 5~8 times respectively compared with the smooth one. Finally, a new high flux heat exchanger was designed and applied instead of conventional one in a refinery.
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9

WITHY, B., M. HYLAND, and B. JAMES. "PRETREATMENT EFFECTS ON THE SURFACE CHEMISTRY AND MORPHOLOGY OF ALUMINIUM." International Journal of Modern Physics B 20, no. 25n27 (October 30, 2006): 3611–16. http://dx.doi.org/10.1142/s0217979206040076.

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Chemical pretreatments are often used to improve the adhesion of coatings to aluminium. XPS and AFM were used to study the effect of these pretreatments on the surface chemistry and morphology of Al 5005. Four pretreatments were investigated, an acetone degrease, boiling water immersion, and two sulphuric acid etches, FPL and P2. Degreasing had no affect on surface morphology and simply added to the adventitious carbon on the surface. Boiling water immersion produced a chemically stable pseudo-boehmitic surface that was quite porous. The acid etches produced porous pitted surfaces similar to each other but significantly different to the other surfaces. The surface chemistry of the acid etched surfaces was variable and dependant on atmospheric conditions on removal from etch due to the very active surface that the etch produced.
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10

Polyaev, V. M., and B. V. Kichatov. "Boiling of Liquid on Surfaces with Porous Coatings;." Heat Transfer Research 35, no. 5-6 (2004): 406–20. http://dx.doi.org/10.1615/heattransres.v35.i56.90.

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Дисертації з теми "Boiling on porous surfaces"

1

Pasek, Ari Darmawan. "Pool boiling on porous surfaces in cryogenic and refrigerant liquids." Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315511.

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2

Furberg, Richard. "Enhanced Boiling Heat Transfer on a Dendritic and Micro-Porous Copper Structure." Doctoral thesis, KTH, Tillämpad termodynamik och kylteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-47538.

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A novel surface structure comprising dendritically ordered nano-particles of copper was developed during the duration of this thesis research project. A high current density electrodeposition process, where hydrogen bubbles functioned as a dynamic mask for the materials deposition, was used as a basic fabrication method. A post processing annealing treatment was further developed to stabilize and enhance the mechanical stability of the structure. The structure was studied quite extensively in various pool boiling experiments in refrigerants; R134a and FC-72. Different parameters were investigated, such as; thickness of the porous layer, presence of vapor escape channels, annealed or non-annealed structure. Some of the tests were filmed with a high speed camera, from which visual observation were made as well as quantitative bubble data extracted. The overall heat transfer coefficient in R134a was enhanced by about an order of magnitude compared to a plain reference surface and bubble image data suggests that both single- and two-phase heat transfer mechanisms were important to the enhancement. A quantitative and semi-empirical boiling model was presented where the main two-phase heat transfer mechanism inside the porous structure was assumed to be; micro-layer evaporation formed by an oscillating vapor-liquid meniscus front with low resistance vapor transport through escape channels. Laminar liquid motion induced by the oscillating vapor front was suggested as the primary single-phase heat transfer mechanism. The structure was applied to a standard plate heat exchanger evaporator with varying hydraulic diameter in the refrigerant channel. Again, a 10 times improved heat transfer coefficient in the refrigerant channel was recorded, resulting in an improvement of the overall heat transfer coefficient with over 100%. A superposition model was used to evaluate the results and it was found that for the enhanced boiling structure, variations of the hydraulic diameter caused a change in the nucleate boiling mechanism, which accounted for the largest effect on the heat transfer performance. For the standard heat exchanger, it was mostly the convective boiling mechanism that was affected by the change in hydraulic diameter. The structure was also applied to the evaporator surface in a two-phase thermosyphon with R134a as working fluid. The nucleate boiling mechanism was found to be enhanced with about 4 times and high speed videos of the enhanced evaporator reveal an isolated bubble flow regime, similar to that of smooth channels with larger hydraulic diameters. The number and frequency of the produced bubbles were significantly higher for the enhanced surface compared to that of the plain evaporator. This enhanced turbulence and continuous boiling on the porous structure resulted in decreased oscillations in the thermosyphon for the entire range of heat fluxes.
QC 20111111
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3

Carbonell, Ventura Montserrat. "Estudio experimental del proceso de calentamiento de medios porosos saturados hasta ebullición-"Dryout" de su fase líquida." Doctoral thesis, Universitat Politècnica de Catalunya, 2000. http://hdl.handle.net/10803/6743.

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La experimentación y posterior modelización de los procesos de transporte y transferencia de calor y de masa en medios poroso saturados encuentra un gran número de dificultades que se derivan fundamentalmente de la heterogeneidad del propio medio, de la metodología de su parametrización estructural y física para asimilarlo a un medio continuo.

Los objetivos planteados en la presente tesis se han orientado hacia un mejor conocimiento de la influencia de diversos parámetros estructurales del medio poroso, así como de las propiedades de las substancias que constituyen la matriz sólida y la fase fluida saturante, en las características de ebullición de un medio poroso inicialmente saturado, calentado por su frontera inferior y limitado por una capa superior del mismo líquido saturante.

A tal fin, se ha estudiado la influencia de la estructura del medio poroso (granular o fibrilar) y de la naturaleza de la sustancia que constituye la matriz sólida sobre la permeabilidad del medio poroso al agua y a una solución acuosa de tensioactivo, de baja concentración. Así mismo se ha estudiado la influencia respecto a la conductividad y difusividad térmicas efectivas en régimen no estacionario. Por último, utilizando la misma variedad de medios porosos saturados, se estudia el proceso de ebullición hasta que se alcanzan condiciones de "dryout", y se analizan las consecuencias que resultan de la variación de la estructura física del medio poroso, de la naturaleza de la sustancia que constituye su matriz sólida y de las propiedades del fluido saturante.

En lo referente a las características fluidodinámicas y térmicas de los medios porosos estudiados se ha podido concluir:

- La adición de un tensioactivo al agua saturante del medio poroso produce un comportamiento diferente según la naturaleza del sólido: en caso de inorgánica (arena) ocasiona un aumento de la permeabilidad intrínseca, mientras que en caso de orgánica (fibras de algodón) produce una reducción tanto mayor cuanto menor es la porosidad del medio poroso. Las causas de este diferente comportamiento, son las notables diferencias de absorción del tensioactivo según el tipo de sólido (orgánico o inorgánico) y la mejora substancial de la humectación de la superficie del sólido inorgánico por el fluido lo que activa la eficacia de desplazamiento de toda fase no acuosa adsorbida o retenida entre partículas.

- La difusividad térmica efectiva promediada espacialmente tiende al valor de la difusividad del componente del medio poroso de menor difusividad térmica a medida que transcurre el tiempo de calentamiento.


- La difusividad térmica efectiva de los medios porosos saturados en los que s / l < 1 se aproxima a la de la fase líquida; en los medios para los que s / l >> 1, dicha difusividad térmica efectiva es un grado de orden superior a la de la fase líquida.

- La adición de tensioactivo a la fase líquida saturante provoca la disminución de la conductividad térmica efectiva de medio poroso saturado en aquellos en que la fase sólida es granular e inorgánica.


En lo referente al proceso de calentamiento de un medio poroso saturado hasta ebullición-"dryout" de su fase líquida se ha descrito un modelo físico de comportamiento de los diferentes medios porosos que comporta las siguientes fases:

i) Calentamiento del medio hasta la temperatura de saturación de su fase líquida, con evidente aumento de volumen de las fases sólida y líquida por dilatación térmica.
ii) Proceso de evaporación con formación de una capa bifásica cuya frontera superior se desplaza a la velocidad del frente de vapor. Simultáneamente se produce una disminución de la presión fluidoestática en la frontera de la capa bifásica, lo que se traduce en una reducción del reflujo de líquido hacia la placa calefactora.
iii) Total desaturación de la entrefase medio poroso-placa calefactora al recibir por reflujo menos líquido del que es capaz de evaporar la placa calefactora. Aparición del "dryout" y elevación progresiva de la temperatura de la placa.
iv) Aparición, en algún caso, de un fenómeno de basculamiento de la fase líquida desde la capa subenfriada a la zona desaturada del medio poroso.
A large number of difficulties are found in the experimentation and later modelization of transport and transfer heat and mass process in saturated porous media, which basically derive from the heterogeneity of the medium, the methodology of structural and physic parameterization to assimilate it to a continuous medium.

The raised aims in this doctoral thesis have been directed towards a better knowledge of the influence of several structural parameters of the porous medium, as well as of the properties of the solid matrix and the saturating fluid phase, in the characteristics of boiling of an initially saturated porous medium, heated by its lower boundary and limited by an upper layer of the same saturating liquid.

For this, the influence of the structure of the porous medium (granular or fibrous) and the nature of the solid matrix on the permeability to water and to a surfactant solution of lower concentration have been studied. The influence in relation to effective thermal conductivity and diffusivity in unstationary regime has also been studied. Finally, the boiling process until to achieve dryout conditions has been studied, and the consequences result from the variation of the physical structure of the porous medium, the nature of the solid matrix and the properties of the saturating fluid have been analyzed.

About the fluid dynamic and thermal characteristics of the porous media studied, the thesis concludes that:

- The addition of a surfactant to the saturating water of the porous medium produces a different behaviour depending on the nature of the solid: in inorganic matrix (sand) occasions an increase in the intrinsic permeability, whereas in organic matrix (cotton fibres) produces a decrease as greater as smaller is the porosity of the porous medium. The reasons of this different behaviour are the notable differences of absorption of the surfactant depending on the sort of solid matrix (organic or inorganic) and the important increase of the wetting of the inorganic solid's surface by the fluid activating the displacement of all adsorbed or retained not watery phase between particles.

- The spatially averaged effective thermal diffusivity tends to the value of the diffusivity of the component of the porous medium with lower thermal diffusivity throughout the boiling process.

- The effective thermal diffusivity of the saturated porous media which have s / l < 1 approaches to of the liquid phase; in the media with s / l >> 1, the effective thermal diffusivity is a grade of upper order to the of liquid phase.

- The addition of surfactant to the saturating liquid phase gives rise to the decrease of the effective thermal conductivity of the saturated porous medium with granular and inorganic solid phase.


A physical model of behaviour of the different saturated porous media concerning heating process until to achieve dryout conditions has been described considering the next phases:

i) Heating of the medium until the saturation temperature of its liquid phase, with evident increase of volume of the solid and liquid phases by thermal dilatation.
ii) Evaporation process with creation of a biphasic layer whose upper boundary displaces to the velocity of the vapour front. Simultaneously a decrease of the fluid static pressure in the boundary of the biphasic layer is produced, what result in a reduction of the reflux of liquid towards the heating plate.
iii) Total unsaturation of the porous medium-heating plate interphase caused by to receive less liquid by reflux that the heating plate is capable of evaporating.
iv) Appearance, in some case, of a fast phenomenon of turn upside down of the liquid phase from subcooled layer to the unsaturated zone of the porous medium.
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4

Witharana, Sanjeeva. "Boiling of refrigerants on enhanced surfaces and boiling of nanofluids." Licentiate thesis, KTH, Energy Technology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1589.

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5

Sriraman, Sharan Ram. "Pool boiling on nano-finned surfaces." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2091.

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6

Roberts, Ian David. "Droplet evaporation from porous surfaces." Thesis, University of Manchester, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294978.

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7

Webb, Stephen David. "Jet impingement on porous surfaces." Thesis, University of Southampton, 2006. https://eprints.soton.ac.uk/47117/.

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A series of experiments are described, documenting the flow resulting from the normal impingement of planar and axisymmetric jets onto a porous surface. Six different porous surfaces with open area ratios of 23, 26, 31, 37, 44 and 54% (β = 0.23, 0.26, 0.31, 0.37, 0.44 and 0.54) were placed in low speed (usually 40m/s exit velocity) air jets sufficiently far from the jet exit for the jet to be self similar. The β=0.31, 0.37, 0.44 and 0.54 surfaces were wove wire mesh. Exit Reynolds number based on jet exit diameter is 3x104 for the axisymmetric case and based on exit width from 0.5x104 to 2.1x104 for the planar case. For β=0.44 and β=0.54 the impingement of the jet for both planar and axisymmetric geometries can be summarised as a widening of the jet as it passes through the mesh, followed by a region of reduced entrainment. For β=0.37 and below, there is evidence of wall jets on the upstream side of the surface. For the β=0.31 mesh and β=0.26 perforated plate, there are marked differences between the axisymmetric and planar cases. For the planar cases the flow is turned downstream of the porous surface away from the centreline such that on the centreline the axial velocity falls to zero, whilst a clear jet remains in the axisymmetric cases. Downstream of the β=0.23 porous surface there is a clear bounded jet in both planar and axisymmetric cases. The presence of a counter-flow at some distance from the centreline, downstream of the surface inhibits entrainment into the downstream jet; its growth rate and velocity decay rate are reduced
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Zhang, Ke. "Enhanced boiling heat transfer on micro/nano structured surfaces." Thesis, Boston University, 2013. https://hdl.handle.net/2144/21284.

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Анотація:
Thesis (M.Sc.Eng.) PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.
Boiling heat transfer is a critical process in large-scale industrial applications such as steam engines and heat exchangers in power plants, and in microscopic heat transfer devices such as heat pipes and microchannels for cooling electronic chips. Enhancing boiling heat transfer thus has great significance on lots of energy transportation and utilization systems. Recent studies has suggested that micro/nano structured surfaces can produce considerably different boiling heat transfer curves than normal plain surfaces, resulting in different values of the critical heat flux (CHF) and heat transfer coefficient (HTC). In this thesis, pool boiling on several new micro/nano structured surfaces was experimentally investigated to further understand the mechanism of boiling heat transfer and increase boiling performance. We first evaluated enhanced boiling heat transfer on three kinds of micro/nano structured super-hydrophilic surfaces: 1) nanowire coated super-hydrophilic surfaces, 2) hybrid microscale cavity and nanowire structured surfaces and 3) hybrid microscale pillar and nanowire structured surfaces. All three surfaces showed significant enhancement of CHF and HTC compared to plain silicon surfaces. Combined micro/nano structured surfaces presented better performance than nanowire coated surfaces suggesting that both active nucleation density and surface roughness significantly affect boiling heating transfer. Experimental investigations indicate an optimum design both in size (~ 20μ𝑚) and density (between 0 and 10000=cm^2) of cavities for microscale cavity/nanowire structured surfaces. The highest CHF and peak HTC values were obtained on microscale pillar/nanowire structured surfaces. Among the test surfaces, the largest enhancements of CHF and peak HTC were 228% and 298%, respectively, compared to plain silicon surfaces. For a better understanding of the boiling phenomena, pool boiling on super-hydrophobic surfaces was also studied. We found that, for super-hydrophobic surfaces, the major heat transfer mechanism at the initial boiling regime is natural convection of liquid water. In conclusion, micro/nano structured surfaces can greatly influence nucleate boiling heat transfer. The various physical attributes employed with the structured surfaces further revealed the profound influence of surface topography on enhancing boiling heat transfer.
2031-01-01
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9

Kim, Dae Whan. "Convection and flow boiling in microgaps and porous foam coolers." College Park, Md. : University of Maryland, 2007. http://hdl.handle.net/1903/7446.

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Анотація:
Thesis (Ph. D.) -- University of Maryland, College Park, 2007.
Thesis research directed by: Mechanical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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10

Kelley, Mitchell Joseph. "Experimental design for study of nucleate boiling in porous structures." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/68530.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 48).
The superheat required to initiate nucleate boiling inside porous wicks is not well understood in practice. This thesis reports the design of an experimental setup for investigating the onset of vapor nucleation in sintered porous structures. Pressure sensing was evaluated as an effective means of detecting the onset of nucleation. Thermal studies were conducted with a custom finite difference script in conjunction with finite element analysis. Heat conduction through a three dimensional wick was reduced to one dimensional conduction via symmetry and design constraints. The wick was optimized to achieve a temperature drop of 30 *C at a common heat pipe operating temperature of 70 °C.
by Mitchell Joseph Kelley.
S.B.
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Книги з теми "Boiling on porous surfaces"

1

Roberts, I. D. Droplet evaporation from porous surfaces. Manchester: UMIST, 1995.

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2

Gladkov, S. O. Dielectric Properties of Porous Media. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003.

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3

Bejan, Adrian. Porous and Complex Flow Structures in Modern Technologies. New York, NY: Springer New York, 2004.

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4

Marcelo J.S. de Lemos. Turbulent Impinging Jets into Porous Materials. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012.

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5

Delgado, J.M.P.Q. and SpringerLink (Online service), eds. Transport Processes in Porous Media. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012.

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6

Aharonov, Einat. Solid-fluid interactions in porous media: Processes that form rocks. [Woods Hole, Mass: Massachusetts Institute of Technology, Woods Hole Oceanographic Institution, Joint Program in Oceanography/Applied Ocean Science and Engineering, 1996.

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Aharonov, Einat. Solid-fluid interactions in porous media: Processes that form rocks. [Woods Hole, Mass: Massachusetts Institute of Technology, Woods Hole Oceanographic Institution, Joint Program in Oceanography/Applied Ocean Science and Engineering, 1996.

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8

Davison, Lee. High-Pressure Shock Compression of Solids IV: Response of Highly Porous Solids to Shock Loading. New York, NY: Springer New York, 1997.

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9

Tronin, V. N. Energetics and percolation properties of hydrophobic nanoporous media. Hauppauge, N.Y: Nova Science Publishers, 2010.

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10

Ichikawa, Yasuaki. Transport Phenomena in Porous Media: Aspects of Micro/Macro Behaviour. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012.

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Частини книг з теми "Boiling on porous surfaces"

1

Nakayama, Wataru. "Porous Surface Boiling and Its Application to Cooling of Microelectronic Chips." In Convective Heat and Mass Transfer in Porous Media, 1007–30. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3220-6_36.

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2

Tricot, Claude. "Porous Surfaces." In Constructive Approximation, 117–36. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4899-6886-9_7.

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3

Antao, Dion S., Yangying Zhu, and Evelyn N. Wang. "Boiling on Enhanced Surfaces." In Handbook of Thermal Science and Engineering, 1747–93. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-26695-4_43.

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Antao, Dion S., Yangying Zhu, and Evelyn N. Wang. "Boiling on Enhanced Surfaces." In Handbook of Thermal Science and Engineering, 1–47. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-32003-8_43-1.

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5

Webb, Ralph L., and Liang-Han Chien. "Boiling on Structured Surfaces." In Heat Transfer Enhancement of Heat Exchangers, 249–84. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-015-9159-1_14.

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6

Zhu, Yangying, Dion S. Antao, and Evelyn N. Wang. "Bioinspired Surfaces for Enhanced Boiling." In Bioinspired Engineering of Thermal Materials, 47–71. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2018. http://dx.doi.org/10.1002/9783527687596.ch3.

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7

Peng, Xiaofeng. "Boiling in Micro-Structures and Porous Media." In Micro Transport Phenomena During Boiling, 201–32. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-13454-8_8.

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8

Stubos, A. K., and J. M. Buchlin. "Boiling and Dryout in Unconsolidated Porous Media." In Convective Heat and Mass Transfer in Porous Media, 791–822. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3220-6_27.

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Birdi, K. S. "Porous Solid Media (Fractal Surfaces)." In Fractals in Chemistry, Geochemistry, and Biophysics, 129–56. Boston, MA: Springer US, 1993. http://dx.doi.org/10.1007/978-1-4899-1124-7_5.

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10

Teppner, R., and U. Schaflinger. "Bubble Formation on Porous Media Surfaces." In Drop-Surface Interactions, 291–94. Vienna: Springer Vienna, 2002. http://dx.doi.org/10.1007/978-3-7091-2594-6_12.

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Тези доповідей конференцій з теми "Boiling on porous surfaces"

1

Manetti, Leonardo, Igor Seicho Kiyomura, and Elaine Maria Cardoso. "POROUS AND NON-POROUS MICROSTRUCTURED SURFACES FOR BOILING HEAT TRANSFER APPLICATIONS." In Brazilian Congress of Thermal Sciences and Engineering. ABCM, 2018. http://dx.doi.org/10.26678/abcm.encit2018.cit18-0719.

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2

Lin, Zhiping, Tongze Ma, and Zhengfang Zhang. "POOL BOILING ON POROUS SURFACES WITH MICRO-GROOVES." In International Heat Transfer Conference 10. Connecticut: Begellhouse, 1994. http://dx.doi.org/10.1615/ihtc10.4660.

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3

Styrikovich, M. A., Stanislav P. Malyshenko, and A. B. Andrianov. "NONEQUILIBRIUM PHASE TRANSITIONS AT BOILING ON SURFACES WITH POROUS COATINGS." In International Heat Transfer Conference 9. Connecticut: Begellhouse, 1990. http://dx.doi.org/10.1615/ihtc9.170.

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4

Li, Chen, and G. P. Peterson. "Comprehensive Comparisons Between Evaporation and Pool Boiling on Thin Micro Porous Coated Surfaces." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-15905.

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The evaporation and pool boiling on micro porous coated surfaces have been shown to provide among the highest heat transfer rates achievable from any type of surfaces. The heat transfer modes in these surfaces, present a number of interesting similarities and also, some fundamental differences, which are the result of the liquid supply methods to the heated surface. For the evaporation from porous coated surfaces, the liquid return to the heated surface is assisted by the capillary pressure at the liquid-vapor interface; while for pool boiling, gravity is the principal driving force that rewets the surface. In order to better understand the physical phenomena that governs the flow behavior of both the liquid and vapor phases, and the heat transfer process inside the porous media, comprehensive comparisons between these return mechanisms and their respective characteristics, and the performance and the critical heat flux (CHF) for each have been made, based on similar physical situations. These systematic comparisons illustrate that at a lower heat flux, the evaporation and pool boiling curves are almost identical due to the similar heat transfer modes, i.e., convection and nucleate boiling. While with further increases in heat flux, the heat transfer performance of the evaporation on micro porous media is generally superior to pool boiling on an identical surface. This shift is believed to be due to the fact that for evaporation on micro porous media, the heat transfer mode is dominated by the film evaporation, while in pool boiling, it is principally the result of fully developed nucleate boiling. It was also observed that the impact of the effective thermal conductivity of the porous coating on pool boiling performance is larger than for evaporation heat transfer on the identical micro porous coated surfaces. In general, the experimental data indicated that the CHF for evaporation heat transfer is much higher than for pool boiling on the same surfaces. The mechanism of CHF for evaporation on porous coated surfaces is believed to be the capillary limit; while for pool boiling the limit is the result of the hydrodynamic instabilities. This difference in mechanisms is clearly demonstrated by the experimental observations, where initially, the dry out process of the porous coated surfaces during evaporation is gradual, while for pool boiling; the entire surface reaches dry out in a very short time. In addition, the sensitivity of the CHF to the thickness of the porous coatings at a constant volumetric porosity and pore size, as well as the various optimal volumetric porosity of the CHF at a given thickness, are clearly the results of the differences induced by the various CHF mechanisms.
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Rioux, Russell P., Eric C. Nolan, and Calvin H. Li. "A Systematic Study of Pool Boiling Heat Transfer on Multiscale Structured Surfaces." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-36236.

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A study has been conducted to examine the effects of macroscale, microscale, and nanoscale surface modifications in water pool boiling heat transfer and to determine the effects of combining the multiple scales. Nanostructured surfaces were created by acid etching, while microscale and macroscale surfaces were manufactured through a sintering process. Six structures were studied as individual and/or collectively integrated surfaces: polished plain, flat nanostructured, flat porous, modulated porous, nanostructured flat porous, and nanostructured modulated porous. Boiling performance was measured in terms of critical heat flux (CHF) and heat transfer coefficient (HTC). Both HTC and CHF have been greatly improved on all modified surfaces compared to the polished baseline. The CHF and HTC of the hybrid multiscale modulated porous surface have achieved the most significant improvements of 350% and 200% over the polished plain surface, respectively. Nanoscale, microscale, and macroscale integrated surfaces have been proven to have the most significant improvements on HTC and CHF. Experimental results were compared to the predictions of a variety of theoretical models with an attempt to evaluate both microscale and nanoscale models. It was concluded that models for both microscale and nanoscale structured surfaces needed to be further developed to be able to have good quantitative predictions of CHFs on structured surfaces.
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6

Ji, Xianbing, Qiang Xue, Jiliang Xu, and Jia Xu. "Pool boiling heat transfer on ultra-light porous metal foam surfaces." In 2013 International Conference on Materials for Renewable Energy and Environment (ICMREE). IEEE, 2013. http://dx.doi.org/10.1109/icmree.2013.6893817.

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Chien, Liang-Han, Shu-Che Lee, Hon-Zen Wang, and Shao-Wen Chen. "Effects of Fluid Properties and Surface Parameters on Pool Boiling of Porous and Pin-Fin Surfaces." In ASME 2008 First International Conference on Micro/Nanoscale Heat Transfer. ASMEDC, 2008. http://dx.doi.org/10.1115/mnht2008-52187.

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The present experimental study investigated the effect of heater size on pool boiling performance for various fluids. Water, methanol and FC-72 were tested at 50 and 70°C saturation temperature on a smooth surface, a porous surface, a pin-fin surface and a structured surface. The boiling test vessel has a 31 mm by 31 mm internal base area and 100 mm height. The sizes of the heating area are: 31×31, 12×12, 9×9, or 6×6 mm2. The test results of all the three fluids showed that boiling performance is independent on heater size for 31mm × 31mm, 12mm × 12 mm heaters, but the boiling heat transfer coefficients for the smooth surface having 6 mm × 6 mm heating area is approximately 70∼100% higher than those for the 12 mm × 12 mm heating area. The 0.2 mm thick square pin-fins, having 0.2 mm depth and 0.4 mm pitch, yields 2-to-3 folds enhancement of boiling performance in FC-72. For methanol and FC-72, the porous surface yields up to seven folds boiling enhancement as compared with the smooth surface. However, the enhancement ratio of the porous surface, having 0.15 mm average particle diameter, is only 2.3 for water. Boiling phenomena observation by a high speed video system showed that the bubble size depends on surface geometries and fluid properties.
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8

Xu, Kuiyan, and John R. Lloyd. "Pool Boiling of FC-72: A Comparison of Two Thin Porous Coatings on Heat Transfer Enhancement." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81230.

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The present research is an experimental study of pool boiling behavior of surfaces coated with thin porous layers. The fluid employed is FC-72, a highly-wetting dielectric perfluorocarbon with zero ozone-depletion potential (ODP). This creates the potential for electronic cooling application. Different surfaces, including the super-smooth surface (SSS), the High Flux™ surface (HFS), and the new electrochemical deposition surface (EDS) were tested, and the test results were compared. Both subcooled and saturated fluid pools were studied. The boiling hysteresis phenomenon was studied for these surfaces under different boiling conditions, which include the fluid bulk temperature and the non-boiling immersion time. Results of the study showed that the porous-coated surface dramatically enhanced the nucleate boiling heat transfer performance. The boiling hysteresis phenomenon is more prominent on porous-coated surfaces than on smooth surfaces, and subcooling can deteriorate this phenomenon.
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9

El-Genk, Mohamed S., and Jack L. Parker. "Pool Boiling in Saturated and Subcooled FC-72 Dielectric Fluid From a Porous Graphite Surface." In ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-59905.

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Experiments are conducted that investigated pool boiling of FC-72 liquid at saturation and 10, 20, and 30 K subcooling on porous graphite and smooth copper surfaces measuring 10 × 10 mm. The nucleate boiling heat flux, Critical Heat Flux (CHF), and surface superheats at boiling incipience are compared. Theses heat fluxes are also compared with those of other investigators for smooth copper and silicon, etched SiO2, surfaces and micro-porous coating. No temperature excursion at boiling incipience on the porous graphite that occurred at a surface superheats of &lt; 1.0 K. Conversely, the temperature excursions of 24.0 K and 12.4–17.8 K are measured at incipient boiling in saturation and subcooled boiling on copper. Nucleate boiling heat fluxes on porous graphite are significantly higher and corresponding surface superheats are much smaller than on copper. CHF on porous graphite (27.3, 39.6, 49.0, and 57.1 W/cm2 in saturation and 10 K, 20 K, and 30 K subcooled boiling, respectively) are 61.5%–207% higher than those on copper (16.9, 19.5, 23.6, and 28.0 W/cm2, respectively). The surface superheats at CHF on the porous graphite of 11.5 K in saturation and 17–20 K in subcooled boiling are significantly lower that those on copper (25 K and 26–28 K, respectively). In addition, the rate of increase of CHF on porous graphite with increased subcooling is ~ 125% higher than that on copper.
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Mele´ndez, Elva, and Rene´ Reyes. "Experimental Description of the Convective Heat Transfer Coefficient for Pool Boiling of Binary Mixtures on Porous Heating Surfaces." In ASME 2003 Heat Transfer Summer Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/ht2003-47196.

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This work presents the experimental results of the effect of porous heating surfaces, and the Marangoni effect on the convective heat transfer coefficient for pool boiling, h. The porous heating surfaces fabricated for these experiments, and the interfacial tension gradients in the binary mixtures reduced the bubbles’ size and their coalescence in the proximity of the heating surface. The convective heat transfer coefficient was calculated for the boiling of pure water and three aqueous mixtures with 12, 16, and 20% weight of ethanol on five different porous coverings on the heating element. Some combinations of these variables were studied in a 32 factorial design, and represented by the response surface calculated. The maximum h for boiling of pure water on the bare surface of the heating element was 50 kW/m2 °C. Using the porous coverings, the maximum h value was 180 kW/m2 °C. For boiling the binary mixtures on the smooth heating element surface the maximum h value was 65 kW/m2 °C, while on the porous coverings the values of h attained a maximum of 220 kW/m2 °C. The maximum values of h correspond to the composition of 16% ethanol, and a porous covering with the smallest porous diameter.
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Звіти організацій з теми "Boiling on porous surfaces"

1

Barclay Jones. Modeling and Thermal Performance Evaluation of Porous Curd Layers in Sub-Cooled Boiling Region of PWRs and Effects of Sub-Cooled Nucleate Boiling on Anomalous Porous Crud Deposition on Fuel Pin Surfaces. Office of Scientific and Technical Information (OSTI), June 2005. http://dx.doi.org/10.2172/841238.

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2

Yortsos, Y. C. Percolation models for boiling and bubble growth in porous media. Office of Scientific and Technical Information (OSTI), May 1991. http://dx.doi.org/10.2172/5788155.

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Gupta, P., A. C. Dillon, A. S. Bracker, and S. M. George. FTIR Studies of H2O and D2O Decomposition on Porous Silicon Surfaces. Fort Belvoir, VA: Defense Technical Information Center, July 1990. http://dx.doi.org/10.21236/ada226581.

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4

Kedzierski, Mark A. Calorimetric and visual measured of R123 pool boiling on four enhanced surfaces. Gaithersburg, MD: National Institute of Standards and Technology, 1995. http://dx.doi.org/10.6028/nist.ir.5732.

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R.F. Voelker. Thermal-Hydraulics and Electrochemistry of a Boiling Solution in a Porous Sludge Pile A Test Methodology. Office of Scientific and Technical Information (OSTI), May 2001. http://dx.doi.org/10.2172/821678.

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6

El-Genk, M. S., and A. G. Glebov. Effect of subcooling and wall thickness on pool boiling from downward-facing curved surfaces in water. Office of Scientific and Technical Information (OSTI), September 1995. http://dx.doi.org/10.2172/107000.

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7

Curcio, L. A., and E. F. Somerscales. Pool boiling of enhanced heat transfer surfaces in refrigerant-oil mixtures and aqueous calcium sulfate solutions. Office of Scientific and Technical Information (OSTI), August 1994. http://dx.doi.org/10.2172/10176548.

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8

Taylor, S., J. Lever, K. Burgess, R. Stroud, D. Brownlee, L. Nittler, A. Bardyn, et al. Sampling interplanetary dust from Antarctic air. Engineer Research and Development Center (U.S.), February 2022. http://dx.doi.org/10.21079/11681/43345.

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We built a collector to filter interplanetary dust particles (IDPs) larger than 5 µm from the clean air at the Amundsen Scott South Pole station. Our sampling strategy used long duration, continuous dry filtering of near-surface air in place of short duration, high-speed impact collection on flags flown in the stratosphere. We filtered ~107 m³ of clean Antarctic air through 20 cm diameter, 3 µm filters coupled to a suction blower of modest power consumption (5–6 kW). Our collector ran continuously for 2 years and yielded 41 filters for analyses. Based on stratospheric concentrations, we predicted that each month’s collection would provide 300–900 IDPs for analysis. We identified 19 extraterrestrial (ET) particles on the 66 cm² of filter examined, which represented ~0.5% of the exposed filter surfaces. The 11 ET particles larger than 5 µm yield about a fifth of the expected flux based on >5 µm stratospheric ET particle flux. Of the 19 ET particles identified, four were chondritic porous IDPs, seven were FeNiS beads, two were FeNi grains, and six were chondritic material with FeNiS components. Most were <10 µm in diameter and none were cluster particles. Additionally, a carbon-rich candidate particle was found to have a small ¹⁵N isotopic enrichment, supporting an ET origin. Many other candidate grains, including chondritic glasses and C-rich particles with Mg and Si and FeS grains, require further analysis to determine if they are ET. The vast majority of exposed filter surfaces remain to be examined.
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Or, Dani, Shmulik Friedman, and Jeanette Norton. Physical processes affecting microbial habitats and activity in unsaturated agricultural soils. United States Department of Agriculture, October 2002. http://dx.doi.org/10.32747/2002.7587239.bard.

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experimental methods for quantifying effects of water content and other dynamic environmental factors on bacterial growth in partially-saturated soils. Towards this end we reviewed critically the relevant scientific literature and performed theoretical and experimental studies of bacterial growth and activity in modeled, idealized and real unsaturated soils. The natural wetting-drying cycles common to agricultural soils affect water content and liquid organization resulting in fragmentation of aquatic habitats and limit hydraulic connections. Consequently, substrate diffusion pathways to soil microbial communities become limiting and reduce nutrient fluxes, microbial growth, and mobility. Key elements that govern the extent and manifestation of such ubiquitous interactions include characteristics of diffusion pathways and pore space, the timing, duration, and extent of environmental perturbations, the nature of microbiological adjustments (short-term and longterm), and spatial distribution and properties of EPS clusters (microcolonies). Of these key elements we have chosen to focus on a manageable subset namely on modeling microbial growth and coexistence on simple rough surfaces, and experiments on bacterial growth in variably saturated sand samples and columns. Our extensive review paper providing a definitive “snap-shot” of present scientific understanding of microbial behavior in unsaturated soils revealed a lack of modeling tools that are essential for enhanced predictability of microbial processes in soils. We therefore embarked on two pronged approach of development of simple microbial growth models based on diffusion-reaction principles to incorporate key controls for microbial activity in soils such as diffusion coefficients and temporal variations in soil water content (and related substrate diffusion rates), and development of new methodologies in support of experiments on microbial growth in simple and observable porous media under controlled water status conditions. Experimental efforts led to a series of microbial growth experiments in granular media under variable saturation and ambient conditions, and introduction of atomic force microscopy (AFM) and confocal scanning laser microscopy (CSLM) to study cell size, morphology and multi-cell arrangement at a high resolution from growth experiments in various porous media. The modeling efforts elucidated important links between unsaturated conditions and microbial coexistence which is believed to support the unparallel diversity found in soils. We examined the role of spatial and temporal variation in hydration conditions (such as exist in agricultural soils) on local growth rates and on interactions between two competing microbial species. Interestingly, the complexity of soil spaces and aquatic niches are necessary for supporting a rich microbial diversity and the wide array of microbial functions in unsaturated soils. This project supported collaboration between soil physicists and soil microbiologist that is absolutely essential for making progress in both disciplines. It provided a few basic tools (models, parameterization) for guiding future experiments and for gathering key information necessary for prediction of biological processes in agricultural soils. The project sparked a series of ongoing studies (at DTU and EPFL and in the ARO) into effects of soil hydration dynamics on microbial survival strategy under short term and prolonged desiccation (important for general scientific and agricultural applications).
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Litaor, Iggy, James Ippolito, Iris Zohar, and Michael Massey. Phosphorus capture recycling and utilization for sustainable agriculture using Al/organic composite water treatment residuals. United States Department of Agriculture, January 2015. http://dx.doi.org/10.32747/2015.7600037.bard.

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Анотація:
Objectives: 1) develop a thorough understanding of the sorption mechanisms of Pi and Po onto the Al/O- WTR; 2) determine the breakthrough range of the composite Al/O-WTR during P capturing from agro- wastewaters; and 3) critically evaluate the performance of the composite Al/O-WTR as a fertilizer using selected plants grown in lysimeters and test-field studies. Instead of lysimeters we used pots (Israel) and one- liter cone-tainers (USA). We conducted one field study but in spite of major pretreatments the soils still exhibited high enough P from previous experiments so no differences between control and P additions were noticeable. Due to time constrains the field study was discontinued. Background: Phosphorous, a non-renewable resource, has been applied extensively in fields to increase crop yield, yet consequently has increased the potential of waterway eutrophication. Our proposal impetus is the need to develop an innovative method of P capturing, recycling and reuse that will sustain agricultural productivity while concurrently reducing the level of P discharge from and to agricultural settings. Major Conclusions & Achievements: An innovative approach was developed for P removal from soil leachate, dairy wastewater (Israel), and swine effluents (USA) using Al-based water treatment residuals (Al- WTR) to create an organic-Al-WTR composite (Al/O-WTR), potentially capable of serving as a P fertilizer source. The Al-WTR removed 95% inorganic-P, 80% to 99.9% organic P, and over 60% dissolved organic carbon from the agro-industrial waste streams. Organic C accumulation on particles surfaces possibly enhanced weak P bonding and facilitated P desorption. Analysis by scanning electron microscope (SEM- EDS), indicated that P was sparsely sorbed on both calcic and Al (hydr)oxide surfaces. Sorption of P onto WW-Al/O-WTR was reversible due to weak Ca-P and Al-P bonds induced by the slight alkaline nature and in the presence of organic moieties. Synchrotron-based microfocused X-ray fluorescence (micro-XRF) spectrometry, bulk P K-edge X-ray absorption near edge structure spectroscopy (XANES), and P K-edge micro-XANES spectroscopy indicated that adsorption was the primary P retention mechanism in the Al- WTR materials. However, distinct apatite- or octocalciumphosphatelike P grains were also observed. Synchrotron micro-XRF mapping further suggested that exposure of the aggregate exteriors to wastewater caused P to diffuse into the porous Al-WTR aggregates. Organic P species were not explicitly identified via P K-edge XANES despite high organic matter content, suggesting that organic P may have been predominantly associated with mineral surfaces. In screen houses experiments (Israel) we showed that the highest additions of Al/O-WTR (5 and 7 g kg⁻¹) produced the highest lettuce (Lactuca sativa L. var. longifolial) yield. Lettuce yield and P concentration were similar across treatments, indicating that Al/O- WTR can provide sufficient P to perform similarly to common fertilizers. A greenhouse study (USA) was utilized to compare increasing rates of swine wastewater derived Al/O-WTR and inorganic P fertilizer (both applied at 33.6, 67.3, and 134.5 kg P₂O₅ ha⁻¹) to supply plant-available P to spring wheat (TriticumaestivumL.) in either sandy loam or sandy clay loam soil. Spring wheat straw and grain P uptake were comparable across all treatments in the sandy loam, while Al/O-WTR application to the sandy clay loam reduced straw and grain P uptake. The Al/O-WTR did not affect soil organic P concentrations, but did increase phosphatase activity in both soils; this suggests that Al/O-WTR application stimulated microorganisms and enhance the extent to which microbial communities can mineralize Al/O-WTR-bound organic P. Implications: Overall, results suggest that creating a new P fertilizer from Al-WTR and agro-industrial waste sources may be a feasible alternative to mining inorganic P fertilizer sources, while protecting the environment from unnecessary waste disposal.
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