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Littérature scientifique sur le sujet « Pipes with varying section »

Auteur : Grafiati

Publié le 9 mars 2023

Mis à jour le 10 mars 2023

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Articles de revues sur le sujet "Pipes with varying section"

Ao-kui, Xiong, et Wei Qing-ding. « The decay of swirling flows in a type of cross-section-varying pipes ». Applied Mathematics and Mechanics 22, n^o 8 (août 2001) : 983–88. http://dx.doi.org/10.1007/bf02436398.

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Kotorynski, W. P. « Dispersion in Pipes with Slowly Varying Cross-Sections ». SIAM Journal on Mathematical Analysis 25, n^o 3 (mai 1994) : 915–40. http://dx.doi.org/10.1137/s0036141090183730.

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Yu, Hao, Feng Liang, Yu Qian, Junjie Gong, Yao Chen et An Gao. « Phononic Band Gap and Free Vibration Analysis of Fluid-Conveying Pipes with Periodically Varying Cross-Section ». Applied Sciences 11, n^o 21 (8 novembre 2021) : 10485. http://dx.doi.org/10.3390/app112110485.

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Phononic crystals (PCs) are a novel class of artificial periodic structure, and their band gap (BG) attributes provide a new technical approach for vibration reduction in piping systems. In this paper, the vibration suppression performance and natural properties of fluid-conveying pipes with periodically varying cross-section are investigated. The flexural wave equation of substructure pipes is established based on the classical beam model and traveling wave property. The spectral element method (SEM) is developed for semi-analytical solutions, the accuracy of which is confirmed by comparison with the available literature and the widely used transfer matrix method (TMM). The BG distribution and frequency response of the periodic pipe are attained, and the natural frequencies and mode shapes are also obtained. The effects of some critical parameters are discussed. It is revealed that the BG of the present pipe system is fundamentally induced by the geometrical difference of the substructure cross-section, and it is also related to the substructure length and fluid–structure interaction (FSI). The number of cells does not contribute to the BG region, while it has significant effects on the amplitude attenuation, higher order natural frequencies and mode shapes. The impact of FSI is more evident for the pipes with smaller numbers of cells. Moreover, compared with the conventional TMM, the present SEM is demonstrated more effective for comprehensive analysis of BG characteristics and free vibration of PC dynamical structures.

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Xijie, Liu, Sami Ainane et Yap Yit Fatt. « Modeling of liquid-solid flow erosion in curved pipes of gradually varying cross section ». Journal of Physics : Conference Series 1276 (août 2019) : 012028. http://dx.doi.org/10.1088/1742-6596/1276/1/012028.

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LUCHINI, PAOLO, et FRANÇOIS CHARRU. « Consistent section-averaged equations of quasi-one-dimensional laminar flow ». Journal of Fluid Mechanics 656 (1 juillet 2010) : 337–41. http://dx.doi.org/10.1017/s0022112010002594.

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Section-averaged equations of motion, widely adopted for slowly varying flows in pipes, channels and thin films, are usually derived from the momentum integral on a heuristic basis, although this formulation is affected by known inconsistencies. We show that starting from the energy rather than the momentum equation makes it become consistent to first order in the slowness parameter, giving the same results that have been provided until today only by a much more laborious two-dimensional solution. The kinetic-energy equation correctly provides the pressure gradient because with a suitable normalization the first-order correction to the dissipation function is identically zero. The momentum equation then correctly provides the wall shear stress. As an example, the classical stability result for a free falling liquid film is recovered straightforwardly.

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Ključanin, Dino, et Abaz Manđuka. « The cantilever beams analysis by the means of the first-order shear deformation and the Euler-Bernoulli theory ». Tehnički glasnik 13, n^o 1 (23 mars 2019) : 63–67. http://dx.doi.org/10.31803/tg-20180802210608.

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The effect of the Timoshenko theory and the Euler-Bernoulli theory are investigated in this paper through numerical and analytical analyses. The investigation was required to obtain the optimized position of the pipes support. The Timoshenko beam theory or the first order shear deformation theory was used regarding thick beams where the shearing effect of the beam is considered. The study of the thin beams was performed with the Euler-Bernoulli theory. The analysis was done for stainless steel AISI-440C beams with the rectangular cross-section. The steel beams were a cantilever and stressed under varying point-centred load.

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JANG, DONG SOO, EUN-JI LEE, SANG HUN LEE et YONGCHAN KIM. « THERMAL PERFORMANCE OF FLAT PLATE PULSATING HEAT PIPES WITH MINI- AND MICROCHANNELS ». International Journal of Air-Conditioning and Refrigeration 22, n^o 04 (décembre 2014) : 1450025. http://dx.doi.org/10.1142/s2010132514500254.

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This study presents the thermal performance of pulsating heat pipes (PHPs) using distilled water with mini- and microchannels. The PHPs were fabricated with the channels of square cross section which had hydraulic diameters ranged from 1.6 to 3.2 mm in minichannels and from 0.714 to 0.941 mm in microchannels. The performance of the PHPs was measured and analyzed by varying hydraulic diameter, number of turns, filling ratio, and input power. The filling ratio of the working fluid varied from 0% to 100%. The input power was controlled in the range between 3.6 and 150 W. The hydraulic diameter, number of turns, filling ratio, and input power showed strong influence on the performance of the PHP. In the PHP models with mini- and microchannels, optimum working conditions, such as filling ratio and heat input, were quite different according to channel size.

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Trykoz, L. V., S. M. Kamchatnaya, O. M. Pustovoitova et A. O. Atynian. « The Investigation of Prestressed Pressure Pipes, Reinforced with Fiberglass Plastic ». International Journal of Engineering Research in Africa 36 (juin 2018) : 1–11. http://dx.doi.org/10.4028/www.scientific.net/jera.36.1.

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The problem of a combined action of reinforced concrete pipe and fiberglass safety cage. The prestressed cage not only decreases deformability of a pipe under load but protects the material of a pipe from agressive external factors. The process of force transfer from concrete pipe and fiberglass has been analyzed and the equation of stress and deformation for pipes and fiberglass has been deduced. It is shown that stress in fiberglass does not remain constant varying wall thickness, reducing towards the concrete core. Hoop stresses in the concrete core increase towards the centre of a pipe. Unlike known solutions the performed calculations take into account the performance of both layers – concrete and fiberglass. The total stresses in a concrete pipe in the most dangerous section from internal pressure and the reduction by fiberglass winding have been determined. The results obtained in the given work provide with the possibility of modelling long-term properties of composite reinforced concrete constructions and optimization of winding angle of fiberglass casing depending on the diameter of a pipe, tension force and the quantity of reinforcing filler.

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Verbanck, Michel A. « Assessment of sediment behaviour in a cunette-shaped sewer section ». Water Science and Technology 33, n^o 9 (1 avril 1996) : 49–59. http://dx.doi.org/10.2166/wst.1996.0174.

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The accumulation of deposits in sewers causes widespread concerns of either operational or environmental nature. It is believed that a number of sediment-related nuisances can substantially be controlled in adapting the characteristics of sewer pipes as a function of local constraints and circumstances. In particular, key design parameters such as cross-section shape or hydraulic roughness of inner walls are currently selected basing more on empiricism and intuition than on full knowledge of the sediment transport driving processes. A valid track for optimization of these parameters is to run mathematical simulations of the sediment transport behaviour under varying design scenarios. This option, however, supposes that a robust mathematical procedure to compute sediment transport capacity in sewers is available, embracing all primary physical factors of influence. Starting from a theoretical description of shear turbulence suggested by Bagnold (1966), a suspension formula is developed dedicated to the specific sewer flow properties. Applying this formula to the case of a main sewer presenting a composite cross-section allows to illustrate how geometrical discontinuities influence sediment transport characteristics in real conduits.

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Kasivisvanathan, S. R., P. N. Kaloni et K. R. Rajagopal. « Flow of a non-newtonian fluid through axisymmetric pipes of varying cross-sections ». International Journal of Non-Linear Mechanics 26, n^o 5 (1991) : 777–92. http://dx.doi.org/10.1016/0020-7462(91)90028-r.

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Thèses sur le sujet "Pipes with varying section"

MARCELLINI, FRANCESCA. « Conservation laws in gas dynamics and traffic flow ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2009. http://hdl.handle.net/10281/7487.

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This PhD thesis is concerned with applications of nonlinear systems of conservation laws to gas dynamics and traffic flow modeling. The first part is devoted to the analytical description of a fluid flowing in a tube with varying cross section. We study the 2x2 model of the p-system and than, we extend the properties to the full 3x3 Euler system. We also consider a general nxn strictly hyperbolic system of balance laws; we study the Cauchy problem for this system and we apply this result to the fluid flow in a pipe wiyh varying section. Concerning traffic flow, we introduce a new macroscopic model, based on a non-smooth 2x2 system of conservation laws. We study the Riemann problem for this system and the qualitative properties of its solutions that are relevant from the point of view of traffic.

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Rasolonjanahary, Irina. « Wave propagation in pipes of slowly-varying radius with compressible flow ». Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/277876.

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The work presented in this thesis studies acoustic perturbations in slowly varying pipes. The slow variation is introduced in the form of a small parameter ${\epsilon}$ and through this in turn gives rise to a slow axial scale $X$ such that $X = {\epsilon}x$ where $x$ is the normal axial coordinate. This allows an asymptotic approach and the WKB method is used to solve the subsequent mathematical problems. The first deals with the existence of a trapped mode in a hard-walled pipe of varying radius conveying fluid. For the derived leading order propagating mode solution, its amplitude becomes singular at transition points $X_{t}$ and $X_{t'}$ where $X_{t} > 0$ and $X_{t'} < 0$ and thus is unable to propagate past these points. Because of the break down in the solution, this leads to the theory that in the neighbourhood of these points there exists a boundary layer in which the original assumption about having slow variation does not hold. By first seeking the thickness of the layer, valid solutions can then be derived and then matched to the outer solutions in order to produce a uniform solution which holds for the entire axial domain. Once this is achieved, it is then used to derive trapped mode solutions. In this case, the theory used is that of two single turning points which are then combined to obtain the full solution. It is illustrated through consideration of examples and the dependence on ${\epsilon}$ is also shown through various plots. This problem will be considered for a symmetric and asymmetric duct and for differing duct parameters. Problems may arise when the two turning points lie close together and so we seek to improve on the method used by deriving a solution to trapped modes encompassing both turning points, which will be proposed together with some illustrations in order to justify its use and reliability. Next, the case of mode propagations on a thin elastic shell of varying radius conveying fluid is studied. The acoustic solutions of a straight shell in vacuo are first briefly reviewed and then built up by the addition of radius variation and the presence of a stationary fluid. The work presented first outlines the analysis for wave propagation in a slowly-varying thin elastic shell in vacuo. It is found that the shell and the fluid terms are coupled through the fluid pressure term, which is added to the equation governing the radial shell displacements since the pressure is assumed to affect radial motion only. Once the newly corrected equation for the radial shell displacements has been obtained, together with the axial and azimuthal displacements equations, this new system of governing equations is then separated into leading order ${\epsilon}^{0}$ and first order ${\epsilon}^{1}$ systems. In order to simplify the calculations, only the zeroth azimuthal order $m = 0$ will be studied here. With this simplification, a notable result is that the solutions of the torsional motion is decoupled from the axial and radial solutions. Once the dispersion equation is extracted from the leading order system, it can be seen that the axial and radial solutions are in fact coupled. The solution to the in vacuo with varying radius problem is first briefly presented and it is then followed by the solution to the fluid inclusion problem with varying radius, which makes up the main part of this section. The solution is studied for various frequencies and at various points along the shell. In addition, the axial and radial components of the first three modes are examined along with their amplitudes and energy distributions. Finally, mean flow is added and the same analysis is carried out, paying particular attention to the differences which arise in comparison to the stationary flow case.

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Huang, Rong. « Time-varying performance in the cross-section of mutual fund returns ». Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7191/.

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This thesis examines the central question of whether actively managed mutual funds generate returns beyond those offered by passively managed funds. Using a non-parametric change point test and a cross-sectional bootstrap technique, this study conducts the first comprehensive examination of mutual fund performance that explicitly controls for possible time-variation in both alpha and betas of the extended versions of the CAPM, without imposing any specific functional form on the nature of the time-variation in these parameters. We further use an FDR technique that is able to quantify the number of skilled and unskilled managers. Our empirical analysis using these techniques reaches the following conclusions: first, after controlling for time-variation, there is more evidence of manager skill for both net and gross returns than previously documented in the literature (Chapter 4). Second, the estimated proportion of skilled funds in our sample is 8.4%, and 34.1% of the funds are identified as unskilled (Chapter 5). Third, different rules in selecting funds could lead to contradictory inferences on fund performance (Chapter 6).

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Clogan, T. « Applications of a new exact solution of the Navier-stokes equations to flow in pipes of varying width ». Thesis, University of Liverpool, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233818.

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Iacovides, H. « Momentum and heat transport in flow through 180deg. bends of circular cross section ». Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373946.

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Makinde, Oluwole D. « Laminar flow in channels and tubes of varying cross-section : (an exploitation of perturbation theory) ». Thesis, University of Bristol, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389905.

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Tanguay, Michel. « Computer simulations of fluid flow and heat transfer in pipes with internal twisted fins of triangular cross-section ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0034/MQ64250.pdf.

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Parent, Serge. « Experimental and numerical study of steel joist and girder cold-formed web members with periodically-varying section properties ». Thèse, Université de Sherbrooke, 2004. http://savoirs.usherbrooke.ca/handle/11143/1775.

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Ce travail de la recherche est visé au développement d'équations du dessin pour les membres du tissu froid-formés avec les sections du non-uniforme. Ce type de membre regroupe des canaux fermés périodiquement, des canaux cousus et des canaux dos à dos avec les plaques de la latte. Les deux premiers types de membres peuvent être utilisés dans les solives comme une alternative à une section fermée soudée sans couture, pendant que la double assemblée du membre sera utilisée avec les poutres. Les algorithmes du dessin proposés résultent ou en une adaptation de méthodes du dessin classiques pour les colonnes de la latte (Engesser, Bleich, ratios du ciseau critiques), ou dans le développement de nouvelles expressions analytiques (description de série Fourier de périodiquement propriétés variables). Dans tous les cas, les équations proposées sont incorporées dans les niveaux du dessin réels pour les membres structurels froid-formés. Pour valider les algorithmes du dessin développés, épreuves des colonnes du bout aussi bien que les expériences de la solive de l'échelle pleines sont menées statistiquement et sont analysées. Facteurs tels que l'effet d'excentricité et retenue qui résultent du modèle de la soudure qui connecte les tissus aux cordes de l'angle chaud-roulées sont considérées. D'autres paramètres du dessin tels que coefficients de la longueur efficaces appropriés, l'influence de l'anisotropy du drap, des coins cédés ou la retenue associée à un ou deux plaques de la latte est enquêté. Ces variables sont aussi incorporées dans plusieurs éléments finis modèles pour valider les plans du dessin proposés. Ce travail inclut finalement des discussions et des conclusions sur les nouvelles procédures du dessin aussi bien que propositions pour travail de la recherche supplémentaire.

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Vosilov, Rustam, et Nicklas Bergström. « Cross-Section of Stock Returns : : Conditional vs. Unconditional and Single Factor vs. Multifactor Models ». Thesis, Umeå University, Umeå School of Business, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34898.

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The cross-sectional variation of stock returns used to be described by the Capital Asset Pricing Model until the early 90‟s. Anomalies, such as, book-to-market effect and small firm effect undermined CAPM‟s ability to explain stock returns and Fama & French (1992) have shown that simple firm attributes, like, firm size and book-to-market value can explain the returns far better than Beta. Following Fama & French many other researchers examine the explanatory powers of CAPM and other asset pricing models. However, most of those studies use US data. There are some researches done in different countries than US, however more out-of-sample studies need to be conducted.

To our knowledge there are very few studies using the Swedish data and this thesis contributes to that small pool of studies. Moreover, the studies testing the CAPM use the unconditional version of the model. There are some papers suggesting the use of a conditional CAPM that would exhibit better explanatory powers than the unconditional CAPM. Different ways of conditioning the CAPM have been proposed, but one that we think is the least complex and possible to make use of in the business world is the dual-beta model. This conditional CAPM assumes a different relationship between beta and stock returns during the up markets and down markets. Furthermore, the model has not thoroughly been tested outside the US. Our study is the first to use the dual-beta model in Sweden. In addition, the momentum effect has lately been given some attention and Fama & French‟s (1993) three factor model has not been able to explain the abnormal returns related to that anomaly. We test the Fama & French three factor model, CAPM and Carhart‟s four factor model‟s explanatory abilities of the momentum effect using Swedish stock returns. Ultimately, our aim is to find the best model that describes stock return cross-section on the Stockholm Stock Exchange.

We use returns of all the non-financial firms listed on Stockholm Stock Exchange between September, 1997 and April, 2010. The number of companies included in our time sample is 366. The results of our tests indicate that the small firm effect, book-to-market effect and the momentum effect are not present on the Stockholm Stock Exchange. Consequently, the CAPM emerges as the one model that explains stock return cross-section better than the other models suggesting that Beta is still a proper measure of risk. Furthermore, the conditional version of CAPM describes the stock return variation far better than the unconditional CAPM. This implies using different Betas to estimate risk during up market conditions and down market conditions.

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Roberts, Sean David Kerth Christopher R. « Forage quality, animal performance, and carcass traits of steers finished on winter annual ryegrass (Lolium multiflorum Lam.) pasture with varying levels of corn supplementation ». Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Fall/Thesis/ROBERTS_SEAN_9.pdf.

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Livres sur le sujet "Pipes with varying section"

Ontario. Ministry of Transportation. Surveys & Design Office. A user's guide to the "Ontario provincial standards for roads and municipal services". Downsview, Ont : [Ontario Ministry of Transportation], 1992.

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World Explorer : People, Places, and Cultures, Guide to the Essentials Teacher's Manual, Answers to all review and test questions in Guide to the Essentials in English and Spanish, Strategies for reaching students of varying abilities (Prentice Hall, Pearson Education, Section-by-Section Reading Support). Prentice Hall, 2003.

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Licandro, Priscilla, Astrid Fischer et Dhugal J. Lindsay. Cnidaria : Scyphozoa and Non-Colonial Hydrozoa. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780199233267.003.0018.

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This chapter describes the taxonomy of scyphozoa and non-colonial hydrozoa. The Phylum Cnidaria assembles highly diverse primitive invertebrates that carry stinging cells called cnida. The presence of cnida, which are organized in specialized structures called cnidocysts (or nematocysts), makes the organisms of this group venomous to varying degrees. The chapter covers their life cycle, ecology, and general morphology. It includes a section that indicates the systematic placement of the taxon described within the tree of life, and lists the key marine representative illustrated in the chapter (usually to genus or family level). This section also provides information on the taxonomic authorities responsible for the classification adopted, recent changes which might have occurred, and lists relevant taxonomic sources.

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Stern, Marc J. Organizational theories. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198793182.003.0007.

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This chapter summarizes theories related to organizational learning, innovation, adaptation, and performance, directly addressing questions of accountability, leadership, risk, monitoring and evaluation, teamwork, appropriate levels of worker discretion, and collaboration. The theories and lessons shared apply to a wide range of organizational contexts, including both non-profit and for-profit organizations, government agencies, and other types of organizations of varying sizes and structures. They also apply for those working within, across, and outside of organizations on environmental or sustainability-related issues. Each section summarizes a key body of organizational literature and provides guidance on how to apply that knowledge to real world problem solving.

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Magnusson, Eva, et Jeanne Marecek. Setting the Stage. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190658540.003.0001.

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This chapter lays the groundwork for navigating psychological scholarship on gender, sex, and sexualities. It presents some central concepts in these fields, as well as tools for thinking about and asking questions about these concepts and their use. The chapter begins with a discussion of social categories and categorization and then moves to a focus on sex categories. Next is an examination of three concepts that psychologists employ with great frequency, but with varying and sometimes ambiguous meanings: gender, difference, and “the social.” The closing section offers a series of questions to guide students as they read books and articles on gender, sex, and sexualities.

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Winterton, Jonathan. Training, Development, and Competence. Sous la direction de Peter Boxall, John Purcell et Patrick M. Wright. Oxford University Press, 2009. http://dx.doi.org/10.1093/oxfordhb/9780199547029.003.0016.

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This article provides the context for training, development, and competence. In the training section, theory, policy, and practice are considered, including the diversity of national systems for vocational education and training (VET) and the relationship between work organization and workplace learning. The development section is distinguished from training in terms of objectives and scope, while the emergence of Human Resource Development (HRD) is explained not only in terms of a more strategic focus but also in relation to initiatives like corporate universities. The competence section addresses the confusion surrounding the term, contrasting four predominant approaches derived from the USA, the UK, France, and Germany, each of which has influenced other countries to varying degrees. Drawing on these four traditions, a more holistic approach to competence is presented as the model currently being used to structure learning outcomes within the European Qualifications Framework.

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Cerna, Lucie. European High-Skilled Migration Policy. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198815273.003.0005.

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The chapter argues that while Europe needs high-skilled immigrants to fill labour shortages and respond to ageing populations, it continues to struggle recruiting these immigrants due to incre asing political tensions over immigration, which can also affect the highly skilled. These tensions are visible in the varying national policies and Blue Card versions at the EU level. The chapter analyses demographic, economic, and political challenges in Europe and traces high-skilled immigration policy developments over the last decade, both in terms of national policies and the adoption of the EU Blue Card. To demonstrate the variation in Blue Card versions, the chapter presents a newly developed Blue Card Index (BCI) and compares it with an existing index of national high-skilled immigration policies. The indices highlight considerable variation in national policies and Blue Card versions. This has important policy implications, which are discussed in the concluding section.

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Thrumurthy, Sri G., Tania Samantha De Silva, Zia Moinuddin et Stuart Enoch. SBA MCQs for the MRCS Part A. Oxford University Press, 2012. http://dx.doi.org/10.1093/oso/9780199645633.001.0001.

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Specifically designed to help candidates revise for the MRCS exam, this book features 350 Single Best Answer multiple choice questions, covering the whole syllabus. Containing everything candidates need to pass the MRCS Part A SBA section of the exam, it focuses intensively on the application of basic sciences (applied surgical anatomy, physiology, and pathology) to the management of surgical patients. The high level of detail included within the questions and their explanations allows effective self-assessment of knowledge and quick identification of key areas requiring further attention. Varying approaches to Single Best Answer multiple choice questions are used, giving effective exam practice and guidance through revision and exam technique. This includes clinical case questions, 'positively-worded' questions, requiring selection of the most appropriate of relatively correct answers; 'two-step' or 'double-jump' questions, requiring several cognitive steps to arrive at the correct answer; as well as 'factual recall' questions, prompting basic recall of facts.

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Thrumurthy, Sri G., Tania S. De Silva, Zia M. Moinuddin et Stuart Enoch. EMQs for the MRCS Part A. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199645640.001.0001.

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Specifically designed to help candidates revise for the MRCS exam, this book features 250 extended matching questions divided into 96 themes, covering the whole syllabus. Containing everything candidates need to pass the MRCS Part A EMQ section of the exam, the book focuses intensively on topics relating to principles of surgery-in-general, including peri-operative care, post-operative management and critical care, surgical technique and technology, management and legal issues in surgery, clinical microbiology, emergency medicine and trauma management, and principles of surgical oncology. The high level of detail included within the questions and their explanations allows effective self-assessment of knowledge and quick identification of key areas requiring further attention. Varying approaches to extended matching questions are used, giving effective exam practice and guidance through revision and exam technique. This includes clinical case questions, positively-worded questions, requiring selection of the most appropriate of relatively correct answers; 'two-step' or 'double-jump' questions, requiring several cognitive steps to arrive at the correct answer; as well as factual recall questions, prompting basic recall of facts.

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Weisbard, Eric. Songbooks. Duke University Press, 2021. http://dx.doi.org/10.1215/9781478021391.

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In Songbooks, critic and scholar Eric Weisbard offers a critical guide to books on American popular music from William Billings's 1770 New-England Psalm-Singer to Jay-Z's 2010 memoir Decoded. Drawing on his background editing the Village Voice music section, coediting the Journal of Popular Music Studies, and organizing the Pop Conference, Weisbard connects American music writing from memoirs, biographies, and song compilations to blues novels, magazine essays, and academic studies. The authors of these works are as diverse as the music itself: women, people of color, queer writers, self-educated scholars, poets, musicians, and elites discarding their social norms. Whether analyzing books on Louis Armstrong, the Beatles, and Madonna; the novels of Theodore Dreiser, Gayl Jones, and Jennifer Egan; or varying takes on blackface minstrelsy, Weisbard charts an alternative history of American music as told through its writing. As Weisbard demonstrates, the most enduring work pursues questions that linger across time period and genre—cultural studies in the form of notes on the fly, on sounds that never cease to change meaning.

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Chapitres de livres sur le sujet "Pipes with varying section"

Bertelsen, Arnold F. « Flow in Pipes with Varying Cross Sections ». Dans Biomechanical Transport Processes, 41–50. Boston, MA : Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1511-8_6.

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Hammond, P. S., A. W. Meredith, J. R. A. Pearson et J. Billingham. « Modelling Gas-Liquid Flow through Pipes of Variable Cross-Section ». Dans Fluid Mechanics and Its Applications, 239–49. Dordrecht : Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-017-1996-4_22.

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Bird, C., T. N. Phillips et K. Walters. « Secondary Flow of Fluids in Pipes of Non-Circular Cross Section ». Dans Progress and Trends in Rheology V, 143–44. Heidelberg : Steinkopff, 1998. http://dx.doi.org/10.1007/978-3-642-51062-5_61.

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Tunca, Osman. « Optimum Design of Beams with Varying Cross-Section by Using Application Interface ». Dans Springer Tracts in Nature-Inspired Computing, 225–49. Singapore : Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-6773-9_11.

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Jayant, Bhagya, Ark Rukhaiyar, Kunal Dahiya et Ritu Raj. « CFD Analysis for Wind Flow Characteristics of Varying Cross-Section Tall Building Using ANSYS ». Dans Lecture Notes in Civil Engineering, 307–20. Singapore : Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5077-3_25.

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Zhang, Yerong, et Zhiqiang Hu. « A mathematical model for variable cross-section hull girder with time-varying mass characteristics ». Dans Advances in the Analysis and Design of Marine Structures, 309–17. London : CRC Press, 2023. http://dx.doi.org/10.1201/9781003399759-34.

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Kim, Chul Ju, Jae Seok Lee, Sung Hoon Kim et Byung Ho Sung. « An Analysis of Liquid Film Condensation Occurring Inside Rotating Heat Pipes with a Trigonal Cross Section ». Dans Solid State Phenomena, 257–60. Stafa : Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/3-908451-29-9.257.

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Devaki, P., C. H. Badari Narayana, A. Kavitha et S. Sreenadh. « Effect of Permeable Boundaries on the Flow of a Jeffrey Fluid in a Channel of Varying Cross-Section ». Dans Advances in Fluid Dynamics, 231–42. Singapore : Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-4308-1_18.

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Okano, Y., Y. Takagi, T. Ohata, Z. K. Sanchez et K. Kimbara. « Numerical Investigation of the Effect of Fluid Flow on Biofilm Formation in a Channel with Varying Cross-Section ». Dans Advances in Intelligent Systems and Computing, 151–57. Cham : Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-46490-9_22.

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Ismail, Kamal A. R., et Célia V. A. G. Rosolen. « Parametric Study of the Effects of Varying the Airfoil Section, the Chord and Pitch Distributions Along the Propeller Blade ». Dans Mechanisms and Machine Science, 163–77. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-99270-9_12.

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Actes de conférences sur le sujet "Pipes with varying section"

Nguyen, Hung, Shoubo Wang, Ram S. Mohan, Ovadia Shoham et Gene Kouba. « Experimental Investigations of Droplet Deposition and Coalescense in Curved Pipes ». Dans ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-88365.

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Even though there have been several studies conducted by the industry on the use of different inlet devices for gas-liquid separation there have been limited laboratory and field evaluations on the use of external piping configurations as flow conditioning devices upstream of a separator inlet. The results of a systematic study of droplet deposition and coalescence in curved pipe and pipe fittings are reported in this paper. A facility has been designed consisting of two main test sections: a fixed horizontal straight pipe section and an interchangeable 180° return pipe section (or curved pipe section) of the same length. Both inlet and outlet to the 180° return are horizontal, but the plane of the 180° return pipe section can pivot about the axis of the inlet horizontal pipe to an angle as much as 10° downwards allowing downward flow in the return section. Various pipe fittings of different radius of curvature can be installed for comparison in the 180° return. Fittings evaluated in this study included: 180° pipe bend, 2 standard radius elbows (with radius of curvature of 1.5D), 2 long radius elbows (with radius of curvature of 6D), 2 target tee bend, and 2 cushion tee bend. Experiments have been carried out using water and air and varying gas velocities and liquid loadings. In order to compare the performance of geometries, Droplet Deposition Fractions (DDF) were measured in the horizontal straight pipe section and in the 180° return pipe section as a measure of coalescence efficiency. The results demonstrate that higher DDF occurs for curved fittings as compared to the straight pipe section. Two standard (short) radius elbows bend have approximately 10% DDF higher, whereas two long radius elbows along with 180° pipe bend perform better (by 15–20% DDF) than straight pipe. Additionally, no significant differences between DDF’s in three different inclination angles of a curved pipe were observed. It was found that the cushion tees and target tees can coalesce droplets at lower gas velocities but break up droplets at higher gas velocities. It can be concluded that 180° pipe bend or two 6D long radii elbows can serve as a droplet coalescer, a pair of cushion tees or target tee can also work as coalescer at low kinetic energy but as atomizers at high kinetic energy.

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JIA, YANHUI, et ZIXUE GUO. « NUMERICAL STUDY ON THE INNER FLOW FIELD OF PIPES WITH VARYING CROSS-SECTIONS ». Dans CMEM 2017. Southampton UK : WIT Press, 2017. http://dx.doi.org/10.2495/cmem170041.

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Crawford, Susan L., Steven R. Doctor, Anthony D. Cinson, Michael W. Watts, Traci L. Moran et Michael T. Anderson. « Preliminary Assessment of NDE Methods on Inspection of HDPE Butt Fusion Piping Joints for Lack of Fusion With Validation From Mechanical Testing ». Dans ASME 2010 Pressure Vessels and Piping Division/K-PVP Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/pvp2010-25280.

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Studies at the Pacific Northwest National Laboratory (PNNL) in Richland, Washington, are being conducted to evaluate nondestructive examinations (NDE) coupled with mechanical testing of butt fusion joints in high density polyethylene (HDPE) pipe for assessing lack of fusion. The work provides information to the United States Nuclear Regulatory Commission (NRC) on the effectiveness of volumetric inspection techniques of HDPE butt fusion joints in Section III, Division 1, Class 3, buried piping systems in nuclear power plants. This paper describes results from preliminary assessments using ultrasonic and microwave nondestructive techniques and mechanical testing with the high speed tensile impact test and the bend test for determining joint integrity. A series of butt joints were fabricated in 3408, 12 inch (30.5 cm) IPS DR-11 HDPE material by varying the fusion parameters to create good joints and joints containing a range of lack of fusion conditions. Six of these butt joints were volumetrically examined with time of flight diffraction (TOFD), phased array (PA) ultrasound, and the Evisive microwave system. The outer diameter (OD) weld beads were removed for microwave evaluation and the pipes ultrasonically re-evaluated. In two of the six pipes both the outer and inner diameter (ID) weld beads were removed and the pipe joints re-evaluated. Several of the pipes were sectioned and the joints destructively evaluated with the following techniques: high speed tensile test, bend test, and focused immersion ultrasound on a joint section removed from the pipe coupled with slicing through the joint and examining the revealed surfaces. The fusion parameters, nondestructive, and destructive evaluation results will be correlated to validate the effectiveness of what each NDE technology detects and what each does not detect. This is an initial limited study which will aid in identifying key future work.

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Rosen Esquivel, Patricio I., Jan H. M. ten Thije Boonkkamp, Jacques A. M. Dam et Robert M. M. Mattheij. « A Parametric Study of the Effect of Wall-Shape on Laminar Flow in Corrugated Pipes ». Dans ASME-JSME-KSME 2011 Joint Fluids Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajk2011-03044.

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In this paper we study the effect of wall-shape on laminar flow in corrugated pipes. The main objectives of this paper are to characterize how the flow rate varies with wall-shape, and to identify which shapes enhance the flow rate. We conduct our study by numerically solving the Navier-Stokes equations for a periodic section of the pipe. The numerical model is validated with experimental data on the pressure drop and friction factor. The effect of wall-shape is studied by considering a family of periodic pipes, in which the wall-shape is characterized by the amplitude, and the ratio between the lengths of expansion and contraction of a periodic section. We study the effect that varying these parameters has on the flow. We show that for small Reynolds numbers, a symmetric shape yields a higher flow rate than an asymmetric shape. For large Reynolds numbers, a configuration with a large expansion region, followed by a short contraction region, performs better. We show that when the amplitude is fixed, there exists an optimal ratio of expansion/contraction which maximizes the flow rate. The flow rate can be increased by 8%, for a geometry with small period; in the case of a geometry with large period, the flow rate increases by 35%, for large Reynolds number, and even 120% for small Reynolds numbers.

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Ariyoshi, Gen, Daisuke Ito, Yasushi Saito et Kaichiro Mishima. « Turbulent Characteristics in Lead-Bismuth Flows Flowing in Poor and Good Wettability Pipes ». Dans 2016 24th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/icone24-60488.

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Lead-bismuth single-phase and two-phase upward flows in a round tube were measured by using an electro-magnetic probe and an electrical conductivity probe. Experiments were performed under adiabatic conditions by varying the superficial gas and liquid velocity from 0 to 0.04 m/s and 0.1 to 0.2 m/s respectively. From the experimental results, it was found that the local liquid velocity and the void fraction in the lead-bismuth two-phase flow take the maximum value near the wall region at low void fraction conditions. These results indicate bubbles would tend to flow along the wall surface due to the poor wettability of the test section to the lead-bismuth. To verify this hypothesis, the liquid velocity and void fraction were also measured by using a test tube with better wettability. In addition, the experimental results were compared with existing experimental results to evaluate the effect of surface wettability on flow structure of lead-bismuth.

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Özçatalbaş, Mustafa, et Ramazan Aykut Sezmen. « Modeling Transient Heat Transfer and Dry-Out Phenomena in Heat Pipes Using Finite Element Analysis ». Dans ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-23126.

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Abstract Heat pipes are passive two-phase heat transfer devices that used in various heat transport applications because of their high thermal conductance capacities with low temperature differences. One of these applications is aerospace avionics that heat pipes are exposed to transient heat loads. Although heat pipes have been one of the heat removal alternatives for compact electronic devices, they have some restrictions during the usage in such high heat flux areas. In order to use heat pipes as effective heat removal devices, operating heat load range should not be exceeded during the operation of avionics or electronic devices. Out of these operating range, heat pipes no longer perform as effective heat removal devices because of phenomena called dry-out. In this study, a novel Finite Element (FE) Analysis Method was developed to model transient heat transfer behavior in heat pipes including dry-out phenomenon. Transient heat transfer analysis using Finite Element Method (FEM) was conducted to investigate heat pipe thermal performance considering heat flux dependent thermal conductivity under randomly varying heat inputs, which were assumed as heat dissipation of an electronic device. Validation of the FE model was done by using the results given in the literature. Heat pipe was made of Al with a length of LHP = 200 mm. Heat flux and convective heat transfer boundary conditions were used at the evaporator and condenser sections, respectively. Effective thermal conductivity of heat pipe, keff, was calculated by using the heat input depended thermal resistance, Rth, values given in literature. Under transient heat loads, heat flux dependent effective thermal conductivity was defined using user defined subroutines to simulate the dry-out. The transient heat transfer analysis was conducted using ABAQUS commercially available software. Temperature differences between evaporator and condenser sections, ΔT = Te−Tc, and thermal resistance, Rth, values are calculated for varying heat input values and compared with the results that provided in literature.

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O¨rjasaeter, Oddvin, Olav Jan Hauge, Guy Ba¨rs et Per Egil Kvaale. « Crack Growth During Full Scale Reeling Simulation of Pipes With Girth Welds ». Dans ASME 2004 23rd International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2004. http://dx.doi.org/10.1115/omae2004-51365.

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Installation of pipelines by reeling has proved to be an effective method. However, the pipe bending results in very high stress and strain and cannot be handled by conventional design rules, as stated in design codes, e.g. [2]: High strain crack growth must be assessed according to specific case-by-case selected criterions. In the present work the performance of 10” and 12 3/4” pipes with typical weld defects is studied — from initiation of cracks at notches to final fracture. Information was obtained from several sources: full scale cyclic bending of pipes, FE simulations, and small-scale tests. The plasticity during reeling operations results in substantial non-linear behavior due to varying cross section properties, cyclic creep, and different material response at tensile and compression side of the pipe. Hence, a full scale reeling simulation must be carefully planned and include sufficient tolerances. Critical cracks in pipe girth welds initiate mainly from the surface (undercuts, lack of penetration, or lack of fusion), but potentially also internally (lack of fusion or large pores). Various configurations of these parameters were investigated in full scale pipe tests. It was possible to verify both crack propagation during the reeling cycles, and the point of final fracture (for ECA verifications). In pipe design on must assure safe conditions for both reeling operations and for later in-service loading. Proper design tools must be available. Several methods for high strain crack growth analysis were considered and also compared to small-scale specimen data. Conventional strain-life methodology failed to predict the crack propagation accurately. A new approach including a tensile strain range parameter offered promising results.

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Crawford, Susan L., Steven R. Doctor, Anthony D. Cinson, Michael W. Watts, Traci L. Moran et Michael T. Anderson. « Assessment of NDE Methods to Detect Lack of Fusion in HDPE Butt Fusion Joints ». Dans ASME 2011 Pressure Vessels and Piping Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/pvp2011-57908.

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Studies at the Pacific Northwest National Laboratory (PNNL) in Richland, Washington, were conducted to evaluate nondestructive examinations (NDE) coupled with mechanical testing of butt fusion joints in high-density polyethylene (HDPE) pipe for assessing lack of fusion. The work provided information to the United States Nuclear Regulatory Commission (NRC) on the effectiveness of volumetric inspection techniques of HDPE butt fusion joints in Section III, Division 1, Class 3, buried piping systems in nuclear power plants. This paper describes results from assessments using ultrasonic and microwave nondestructive techniques and mechanical testing with the high-speed tensile impact test and the side-bend test for determining joint integrity. A series of butt joints were fabricated in 3408, 12-inch (30.5-cm) IPS DR-11 HDPE material by varying the fusion parameters to create good joints and joints containing a range of lack-of-fusion conditions. Six of these butt joints were volumetrically examined with time-of-flight diffraction (TOFD), phased-array (PA) ultrasound, and the Evisive microwave system. The outer diameter (OD) weld beads were removed for microwave evaluation and the pipes ultrasonically re-evaluated. In two of the six pipes, both the outer and inner diameter (ID) weld beads were removed and the pipe joints re-evaluated. Some of the pipes were sectioned and the joints destructively evaluated with the high-speed tensile test and the side-bend test. The fusion parameters, nondestructive and destructive evaluation results have been correlated to validate the effectiveness of what each NDE technology detects and what each does not detect based on the limited testing that was conducted. No single NDE method detected all of the lack-of-fusion flaws; further a combination of NDE methods did not detect all of the flaws.

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Micklow, Gerald J., Subir Roychoudhury, H. Lee Nguyen et Michael C. Cline. « Emissions Reduction by Varying the Swirler Airflow Split in Advanced Gas Turbine Combustors ». Dans ASME 1992 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1992. http://dx.doi.org/10.1115/92-gt-110.

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A rich burn/quick mix/lean burn (RQL) combustor concept for reducing pollutant emissions is currently under investigation at the NASA Lewis Research Center (LeRC). A numerical study was performed to investigate the chemically reactive flow with liquid spray injection for the RQL combustor. The RQL combustor consists of an airblast atomizer fuel injector, a rich burn section, a converging connecting pipe, a quick mix zone, a diverging connecting pipe and a lean combustion zone. For computational efficiency, the combustor was split into two sub systems, i.e. the fuel nozzle/rich burn section and the quick mix/lean burn section. The current study investigates the effect of varying the mass flow rate split between the swirler passages for an equivalence ratio of 2.0 on fuel distribution, temperature distribution, and emissions for the fuel nozzle/rich burn section of an RQL combustor. The input conditions used in the study were chosen based on tests completed at LeRC. It is seen that optimizing these parameters can substantially improve combustor performance and reduce combustor emissions. The optimal mass flow rate split for reducing NOx emissions based on the numerical study was the same as found by experiment at LeRC.

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Sobhan, C. B., et G. P. (Bud) Peterson. « Modeling of the Flow and Heat Transfer in Micro Heat Pipes ». Dans ASME 2004 2nd International Conference on Microchannels and Minichannels. ASMEDC, 2004. http://dx.doi.org/10.1115/icmm2004-2426.

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The fluid flow and heat transfer characteristics of micro heat pipes are analyzed theoretically, in order to understand the physical phenomena and quantify the influence of various parameters on overall thermal performance of these devices. A one-dimensional model is utilized to solve the governing equations for the liquid/vapor flow and the heat transfer in the heat pipe channel. Variations in the liquid and vapor cross-sectional areas along the axial length of the heat pipe are included and the equations are solved using an implicit finite difference scheme. Appropriate models for fluid friction in small passages with varying cross-sectional areas have been incorporated to yield the axial distribution of the meniscus radius of curvature and the velocity, temperature and pressure in both the liquid and the vapor phases. Using this information, the effective thermal conductivity of the micro heat pipe is modeled, and parametric studies are performed by changing the heat load and cooling rate. The results of the analysis are discussed and compared with other theoretical models and experimental results found in the literature. By so doing, this analysis provides greater insight into the physical phenomena of flow and heat transfer in micro heat pipes and identifies a methodology for optimizing the design of these devices.

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Rapports d'organisations sur le sujet "Pipes with varying section"

Guo, Hui. Time-Varying Risk Premia and The Cross Section of Stock Returns. Federal Reserve Bank of St. Louis, 2002. http://dx.doi.org/10.20955/wp.2002.013.

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Lobanow, Igor E. THEORETICAL MATHEMATICAL MODELING OF HYDRAULIC RESISTANCE IN PIPES WITH TURBULIZERS OF THE CIRCULAR CROSS SECTION AT THE TURBULENT CURRENT. Bulletin of Science and Technical Development, 2018. http://dx.doi.org/10.18411/vntr2018-126-3.

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Ali, Ayman, Ahmed Saidi, Yusef Mehta, Christopher DeCarlo, Mohamed Elshear, Benjamin Cox et Wade Lein. Development and validation of a balanced mix design approach for CIR mixtures using full-scale testing. Engineer Research and Development Center (U.S.), octobre 2022. http://dx.doi.org/10.21079/11681/45704.

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The main goal of this study was to improve the performance of cold in-place recycling (CIR) mixtures by using a balanced mix design (BMD) approach. This study involved preparing and testing CIR mixtures in the lab at varying contents of bituminous additives and constant content of 1% ce-ment and 3% water. Eight combinations of CIR mixtures were produced for this study using two binders (emulsion and foamed asphalt), compaction efforts (30 and 70 gyrations), and curing processes (72 hours at 140°F and 50°F). Results showed that asphalt pavement analyzer, semicircular bend, and indirect tensile strength tests presented the highest correlation with the change of binder contents. The study successfully used the developed BMD for designing CIR mixtures and selecting their optimum binder contents. It then used three balanced CIR mixtures to construct full-scale pavement sections to validate the BMD approach in the field. A heavy vehicle simulator was used to apply different accelerated loadings on each section. Results showed that the CIR section with 2% binder presented the best rutting performance under truck loading and the highest rutting susceptibility under aircraft loading. Conversely, the CIR section with 3% binder presented the highest cracking resistance under both truck and aircraft loading.

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Baral, Aniruddha, Jeffery Roesler et Junryu Fu. Early-age Properties of High-volume Fly Ash Concrete Mixes for Pavement : Volume 2. Illinois Center for Transportation, septembre 2021. http://dx.doi.org/10.36501/0197-9191/21-031.

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High-volume fly ash concrete (HVFAC) is more cost-efficient, sustainable, and durable than conventional concrete. This report presents a state-of-the-art review of HVFAC properties and different fly ash characterization methods. The main challenges identified for HVFAC for pavements are its early-age properties such as air entrainment, setting time, and strength gain, which are the focus of this research. Five fly ash sources in Illinois have been repeatedly characterized through x-ray diffraction, x-ray fluorescence, and laser diffraction over time. The fly ash oxide compositions from the same source but different quarterly samples were overall consistent with most variations observed in SO3 and MgO content. The minerals present in various fly ash sources were similar over multiple quarters, with the mineral content varying. The types of carbon present in the fly ash were also characterized through x-ray photoelectron spectroscopy, loss on ignition, and foam index tests. A new computer vision–based digital foam index test was developed to automatically capture and quantify a video of the foam layer for better operator and laboratory reliability. The heat of hydration and setting times of HVFAC mixes for different cement and fly ash sources as well as chemical admixtures were investigated using an isothermal calorimeter. Class C HVFAC mixes had a higher sulfate imbalance than Class F mixes. The addition of chemical admixtures (both PCE- and lignosulfonate-based) delayed the hydration, with the delay higher for the PCE-based admixture. Both micro- and nano-limestone replacement were successful in accelerating the setting times, with nano-limestone being more effective than micro-limestone. A field test section constructed of HVFAC showed the feasibility and importance of using the noncontact ultrasound device to measure the final setting time as well as determine the saw-cutting time. Moreover, field implementation of the maturity method based on wireless thermal sensors demonstrated its viability for early opening strength, and only a few sensors with pavement depth are needed to estimate the field maturity.

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