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Literatura académica sobre el tema "Marches de rotors"

Autor: Grafiati

Publicado: 25 de mayo de 2024

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Artículos de revistas sobre el tema "Marches de rotors"

Boletis, E. y C. H. Sieverding. "Experimental Study of the Three-Dimensional Flow Field in a Turbine Stator Preceded by a Full Stage". Journal of Turbomachinery 113, n.º 1 (1 de enero de 1991): 1–9. http://dx.doi.org/10.1115/1.2927733.

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The paper describes the experimental investigation of the three-dimensional flow field through a low aspect ratio, high turning turbine stator preceded by a full stage. This configuration simulates as closely as possible the flow conditions for an intermediate stator in a multistage machine, although the use of cylindrical rotor blades does not reflect typical gas turbine design practice. The inlet conditions to the stator are significantly different from those reported in previous investigations dealing with tests in isolated cascades, e.g., Sieverding (1985); Marchal and Sieverding (1977); Sieverding et al. (1984); Klein (1969); Bindon (1979, 1980); Wegel (1970); and Boletis (1985). The inlet flow field to the stator is characterized by both radial and circumferential gradients. Inlet skew occurs on both endwalls but the overall shape does not resemble those that are generated in isolated cascades by rotating the upstream endwalls. Rotor clearance effects are of predominant importance for the flow field at the tip endwall region. The flow field is explored by means of double head four-hole pressure probes in five axial planes from upstream to far downstream of the stator. The results are presented in the form of contour plots and spanwise pitch-averaged distributions.

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You, Young H., Deokhwan Na y Sung N. Jung. "Data Transfer Schemes in Rotorcraft Fluid-Structure Interaction Predictions". International Journal of Aerospace Engineering 2018 (2018): 1–15. http://dx.doi.org/10.1155/2018/3426237.

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For a CFD (computation fluid dynamics)/CSD (computational structural dynamics) coupling, appropriate data exchange strategy is required for the successful operation of the coupling computation, due to fundamental differences between CFD and CSD analyses. This study aims at evaluating various data transfer schemes of a loose CFD/CSD coupling algorithm to validate the higher harmonic control aeroacoustic rotor test (HART) data in descending flight. Three different data transfer methods in relation to the time domain airloads are considered. The first (method 1) uses random data selection matched with the timewise resolution of the CSD analysis whereas the last (method 2) adopts a harmonic filter to the original signals in CFD and CSD analyses. The second (method 3) is a mixture of the two methods. All methods lead to convergent solutions after a few cycles of coupling iterations are marched. The final converged solutions for each of the data transfer methods are correlated with the measured HART data. It is found that both method 1 and method 2 exhibit nearly identical results on airloads and blade motions leading to excellent correlations with the measured data while the agreement is less satisfactory with method 3. The reason of the discrepancy is identified and discussed illustrating CFD-/CSD-coupled aeromechanics predictions.

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Moscatelli, Alberto. "Molecular rotors en marche". Nature Nanotechnology, 4 de agosto de 2017. http://dx.doi.org/10.1038/nnano.2017.174.

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Singh, Atinder Pal y P. S. Ghoshdastidar. "Computer Simulation of Heat Transfer in Alumina and Cement Rotary Kilns". Journal of Thermal Science and Engineering Applications 14, n.º 3 (21 de junio de 2021). http://dx.doi.org/10.1115/1.4051376.

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Abstract This paper presents computer simulation of heat transfer in alumina and cement rotary kilns. The model incorporates radiation exchange among solids, wall, and gas, convective heat transfer from the gas to the wall and the solids, contact heat transfer between the covered wall and solids, and heat loss to the surrounding as well as chemical reactions. The mass and energy balances of gas and solids have been performed in each axial segment of the kilns. The energy equation for the wall is solved numerically by the finite-difference method. The dust entrainment in the gas is also accounted for. The solution marches from the solids inlet to the solids outlet. The kiln length predicted by the present model of the alumina kiln is 77.5 m as compared to 80 m of the actual kiln of Manitius et al. (1974, “Mathematical Model of an Aluminum Oxide Rotary Kiln,” Ind. Eng. Chem. Process Des. Dev., 13(2), pp. 132–142). In the second part, heat transfer in a dry process cement rotary kiln is modeled. The melting of the solids and coating formation on the inner wall of the kiln are also taken into account. A detailed parametric study lent a good physical insight into axial solids and gas temperature distributions, and axial variation of chemical composition of the products in both the kilns.

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Tesis sobre el tema "Marches de rotors"

Duhaze-Pradines, Loric. "Reachability problems for general rotor walks in graphs". Electronic Thesis or Diss., université Paris-Saclay, 2023. http://www.theses.fr/2023UPASG051.

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Nous nous intéressons dans cette thèse aux propriétés algorithmiques d'un automate cellulaire, les marches de rotors. Ce modèle a été introduit de deux manières différentes. Tout d'abord comme une opération élémentaire d'un autre automate cellulaire : les Sandpiles qui modélisent l'effondrement d'une pile de sable lorsque celle-ci devient trop haute. Mais également, par sa ressemblance avec des modèles stochastiques très étudiés que sont les marches aléatoires. En effet, de nombreuses propriétés structurelles des marches aléatoires (temps d'atteinte, temps de couverture, etc...) sont similaires à celles de cet automate complètement déterministe qu'est la marche de rotor. Cette forme de "dérandomisation" de processus aléatoire a été la motivation principale de cette thèse. Plus précisément, une marche de rotor correspond au mouvement d'une particule sur un graphe orienté en suivant la règle suivante : au départ on fixe un ordre (une numérotation) sur les arcs sortants de chacun des sommets du graphe puis, une fois qu'on a définit la position de départ de la particule, chaque fois que cette dernière est sur un sommet, elle le quitte par l'arc de valeur la plus faible qu'elle n'a pas déjà utilisé. Bien entendu, si tous les arcs ont été utilisés, on redémarre avec l'arc de plus faible valeur. Il existe une multitude de problèmes d'accessibilité sur les rotors dont nous nous appliquons à faire une liste dans cette thèse. Nous donnerons également des résultats de complexité pour certains d'entre eux. Puis nous nous intéresserons à un problème d'accessibilité particulier : ARRIVAL. Si l'on considère un graphe avec des puits tel qu'il existe un chemin orienté entre chaque sommet du graphe et au moins l'un de ces puits, une marche de rotor se termine forcément. Hélas, le nombre d'étapes avant que ce processus ne termine peut être exponentiel. En 2017, Dorhau et al. ont présenté un problème, nommé ARRIVAL, qui est de savoir si la particule finit bien sa course dans un puits donné. Ils ont montré qu'il appartenait aux classes de complexité NP et co-NP. Etant donc un bon candidat à être résolu par un algorithme polynomial, nous nous intéressons à ce problème sur une sous-classe de graphe pour laquelle le nombre d'étapes du processus peut être exponentiel : les Tree-like multigraphes. Il s'agit de multigraphes donc le graphe non-orienté sous-jacent est un arbre. Dans ce contexte, nous avons pu montrer que ce problème pouvait être résolu en temps linéaire et même étendre ces résultats à des versions décisionnelles du problème ARRIVAL connues pour être respectivement NP-complète et PSPACE-complète
In this thesis, we focus on the algorithmic properties of a cellular automaton known as rotor walks. This model has been introduced in two distinct ways. Firstly, as a fundamental operation within another cellular automaton known as Sandpiles, which models the collapse of a sand pile when it becomes too high. Secondly, due to its resemblance to well-studied stochastic models, such as random walks. Indeed, numerous structural properties of random walks (hitting times, cover times, etc.) are analogous to those of this completely deterministic automaton called the rotor walk. The main motivation for this thesis stems from this "derandomization" of a random process. More precisely, a rotor walk corresponds to the movement of a particle on a directed graph following the following rule: initially, an order (a numbering) is fixed on the outgoing arcs of each vertex of the graph. Once the starting position of the particle is defined, each time it is on a vertex, it leaves through the arc with the lowest value that it has not already used. Of course, if all arcs have been used, the process restarts with the lowest value arc. There is a multitude of accessibility problems on rotors, and we aim to compile a list of them in this thesis. We also provide complexity results for some of these problems. Subsequently, we turn our attention to a specific accessibility problem: ARRIVAL. Considering a graph with sinks such that there is a directed path between each vertex of the graph and at least one of these sinks, a rotor walk inevitably terminates. Unfortunately, the number of steps before this process concludes can be exponential. In 2017, Dorhau et al. introduced a problem called ARRIVAL, which seeks to determine if the particle successfully reaches a given sink. They demonstrated that it belongs to the complexity classes NP and co-NP. Being a strong candidate for polynomial algorithm resolution, we investigate this problem on a subclass of graphs where the step count of the process can be exponential: Tree-like multigraphs. These are multigraphs whose underlying undirected graph is a tree. In this context, we show that this problem can be solved in linear time, extending these results to decision versions of the ARRIVAL problem, known to be respectively NP-complete and PSPACE-complete

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Maier, Marcel [Verfasser]. "Betrieb einer elektrisch erregten Synchronmaschine mittels kontaktloser, induktiver Energieübertragung auf den Rotor / Marcel Maier". Düren : Shaker, 2020. http://d-nb.info/1213471621/34.

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Pajak, Dominik. "Algorithms for Deterministic Parallel Graph Exploration". Phd thesis, Université Sciences et Technologies - Bordeaux I, 2014. http://tel.archives-ouvertes.fr/tel-01064992.

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Nous étudions dans cette thèse le problème de l'exploration parallèle d'un graphe à l'aide des multiples, synchronisés et mobiles agents. Chaque agent est une entité individuelle qui peut, indépendamment des autres agents, visitez les sommets du graphe ou parcourir ses arêtes. Le but de ensemble des agents est de visiter tous les sommets de graphe. Nous étudions d'abord l'exploration du graphe dans un modèle où chaque agent est équipé de mémoire interne, mais les nœuds n'ont pas de mémoire. Dans ce modèle les agents sont autorisés à communiquer entre eux en échangeant des messages. Nous présentons des algorithmes qui s'exécutent dans un minimum de temps possible pour polynomiale nombre d'agents (polynomiale en nombre de sommets du graphe). Nous étudions aussi quelle est l'impacte de différent méthodes des communications. Nous étudions des algorithmes où les agents peuvent se communiquer à distance arbitraire, mais aussi où communication est possible seulement entre les agents situés dans le même sommet. Dans les deux cas nous présentons des algorithmes efficaces. Nous avons aussi obtenu des limites inférieures qui correspondent bien à la performance des algorithmes. Nous considérons également l'exploration de graphe en supposant que les mouvements des agents sont déterminés par le soi-disant rotor-router mécanisme. Du point de vue d'un sommet fixé, le rotor- router envoie des agents qui visitent les sommet voisins dans un mode round-robin. Nous étudions l'accélération défini comme la proportion entre le pire des cas de l'exploration d'un agent unique et des plusieurs agents. Pour générales graphes, nous montrerons que le gain de vitesse en cas de multi-agent rotor-router est toujours entre fonction logarithmique et linéaire du nombre d'agents. Nous présentons également des résultats optimaux sur l'accélération de multi-agent rotor-router pour cycles, expanseurs, graphes aléatoires, cliques, tores de dimension fixé et une analyse presque optimale pour hypercubes. Finalement nous considérons l'exploration sans collision, où chaque agent doit explorer le graphe de manière indépendante avec la contrainte supplémentaire que deux agents ne peuvent pas occuper le même sommet. Dans le cas où les agents sont donnés le plan de graphe, on présente un algorithme optimal pour les arbres et un algorithme asymptotiquement optimal pour générales graphes. Nous présentons aussi des algorithmes dans le cas de l'exploration sans collision des arbres et des générales graphes dans la situation où les agents ne connaissent pas le graphe. Nous fermons la thèse par des observations finales et une discussion de problèmes ouverts liés dans le domaine de l'exploration des graphes.

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Cunha, Carla Maria Santana Duarte Correia da. "Minimização do número de más viragens na recolha de resíduos sólidos urbanos". Master's thesis, Instituto Superior de Economia e Gestão, 2001. http://hdl.handle.net/10400.5/18825.

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Mestrado em Matemática Aplicada à Economia e à Gestão
O problema da determinação de percursos a efectuar por veículos afectos à remoção de resíduos sólidos urbanos pode ser visto como um problema de optimização de rotas, com procura nos arcos e restrições adicionais. Usualmente os algoritmos para determinar soluções admissíveis para este tipo de problemas não têm em conta o tipo de viragem que os veículos são obrigados a fazer. Dadas as características dos veículos envolvidos na recolha de resíduos, entende-se por má viragem uma inversão de marcha ou uma viragem à esquerda. Na prática é, em geral, exigida a minimização do número de más viragens, devendo mesmo algumas ser impossibilitadas, quer por se tornarem perigosas, quer por questões de regras de trânsito. Neste trabalho o problema da minimização do número de más viragens é definido e modelizado como um problema de redes. São desenvolvidos métodos para a determinação de soluções admissíveis. Os métodos implementados são testados num conjunto de problemas teste gerados aleatoriamente. Como se mostra, os resultados podem ser considerados bastante bons, dado permitirem obter soluções com um baixo número de más viragens sendo evitadas a quase totalidade das inversões de marcha proibidas. Muito embora a heurística se baseie na expansão da rede nos nodos onde as inversões de marcha não são permitidas, os resultados permitiram concluir que nem todos os nodos têm que ser expandidos para que as respectivas inversões de marcha sejam impossibilitadas.
Finding the optimal set of tours for vehicles dedicated to household refuse collection can be looked at as an are routing problem with additional constraints. Typically, the algorithms used in determining feasible solutions to these problems do not account for the type of turn that the vehicles actually must perform. Given the specifíc characteristics of the vehicles assigned to household refuse collection, a bad-turn translates to a U-turn or to a left-turn. In practical terms it is generally mandatory to minimize the total number of bad-turns, some of which really must be avoided either due to its intrinsic danger or to traffic regulation restrictions. Throughout this thesis the problem of minimizing the number of bad-turns is defmed and modeled as a network problem. Some methods are developed to determine feasible solutions. These methods have been tested over a set of randomly generated problems. It is shown that the overall results are to be considered pretty good since they represent feasible solutions with a very low number of bad-turns, where nearly every forbidden U-turns are avoided.
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Lancial, Nicolas. "Effets de la rotation sur la dynamique des écoulements et des transferts thermiques dans les machines électriques tournantes de grande taille". Thesis, Valenciennes, 2014. http://www.theses.fr/2014VALE0021/document.

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EDF exploite sur son parc de production de nombreuses machines électriques tournantes. Les contraintes thermiques subies par celles-ci engendrent des échauffements locaux qui nuisent à leur intégrité. Le présent travail contribue à fournir des méthodes de calcul adaptées à la détection et à la localisation des points chauds. Il participe à améliorer la compréhension des écoulements en rotation et leurs effets sur les transferts thermiques. Plusieurs dispositifs expérimentaux, de complexité ascendante, ont été utilisés pour comprendre et valider les simulations numériques. Une première étude sur une marche descendante (demi-pôle) parcourue par un jet de paroi non-confiné a mis en avant des différences par rapport à un jet confiné ; ces deux cas existent dans un alternateur. Une seconde étude menée sur une cavité tournante confinée a analysé l’impact d’un écoulement de Taylor-Couette-Poiseuille sur la température et la position des points chauds créés, en balayant l’ensemble des régimes d’écoulement. Ces études ont mis en exergue une première méthode de calcul fiable, fondée sur l’étude numérique CHT. Une autre méthode, basée sur la FEM couplée à une méthode inverse, a été testée sur une maquette d’alternateur hydraulique afin de pallier aux temps de calcul longs de la première. Cette méthodologie remonte aux coefficients d’échanges convectifs numériques à partir des mesures du champ thermique du rotor, mais n’est envisageable que lorsque l’on dispose de données expérimentales suffisantes. Ces travaux ont aussi mis en évidence de nouvelles techniques de mesures sans contact, comme l’utilisation d’un pyromètre à haute fréquence pour la mesure de température sur des machines tournantes
EDF operates a large number of electrical rotating machines in its electricity generation capacity. Thermal stresses which affect them can cause local heating, sufficient to damage their integrity. The present work contributes to provide methodologies for detecting hot spots in these machines, better understanding the topology of rotating flows and identifying their effects on heat transfer. Several experimental scale model were used by increasing their complexity to understand and validate the numerical simulations. A first study on a turbulent wall jet over a non-confined backward-facing step (half-pole hydrogenerator) notes significant differences compared to results from confined case : both of them are present in an hydrogenerator. A second study was done on a small confined rotating scale model to determinate the effects of a Taylor-Couette-Poiseuille on temperature distribution and position of hot spots on the heated rotor, by studying the overall flow regimes flow. These studies have helped to obtain a reliable method based on conjugate heat transfer (CHT) simulations. Another method, based on FEM coupled with the use of an inverse method, has been studied on a large model of hydraulic generator so as to solve the computation time issue of the first methodology. It numerically calculates the convective heat transfer from temperature measurements, but depends on the availability of experimental data. This work has also developped new no-contact measurement techniques as the use of a high-frequency pyrometer which can be applied on rotating machines for monitoring temperature

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Libros sobre el tema "Marches de rotors"

Valli, Valentina, Natalia Ailén Carod, Germán Andrés Casella, Jorgelina Araceli Sciorra y Gustavo Mario Radice, eds. Actas I JoBUIFA Jornadas de Becarixs de Unidades de Investigación FdA. Instituto de Historia del Arte Argentino y Americano (IHAAA), 2020. http://dx.doi.org/10.35537/10915/155902.

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Estas primeras Jornadas son una de las tantas experiencias institucionales para pensar el trabajo de la investigación de manera colectiva y colaborativa. Un largo camino se ha recorrido en el área de investigación en artes, y uno de los resultados de dicho recorrido es la respuesta a las convocatorias que se realizan anularmente desde la UNLP para acceder al sistema de becas de posgrado (maestría, doctorado y posdoctorado), así como las Becas de Estímulo a las Vocaciones Científicas (EVC-CIN) para estudiantes de grado que deseen iniciar su formación en investigación. Es gracias a la difusión y promoción del sistema de becas que el campo temático vinculado a las artes ha logrado expandirse incorporando diversidad de disciplinas que van desde las artes escénicas hasta el arte público, por nombrar algunos de los temas que lxs jóvenes investigadores desarrollan. A lo largo de estos años se ha producido una renovación y expansión disciplinar que se enmarca en los intereses particulares de lxs postulantes a becas. También la mirada y los abordajes metodológicos han logrado rotar para incluir miradas y problemáticas actuales como pueden ser los marcos que incluyen las teorías sobre el género. Es desde un espacio institucional, en donde se tejen redes de conocimiento entre las nuevas generaciones, que surge la I JoBUIFA como respuesta a las nuevas demandas de circulación de los saberes, se ha pensado este espacio como un lugar de intercambio y retralimentación en donde podemos construir, pensar, reflexionar saberes y experiencia en torno a los nuevos caminos que se abren en la investigación en arte.

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Capítulos de libros sobre el tema "Marches de rotors"

"Note on References and Abbreviations". En Joseph Roth's March into History, ix—xii. Boydell and Brewer, 2008. http://dx.doi.org/10.1515/9781571138019-002.

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"Index". En Joseph Roth's March into History, 217–24. Boydell and Brewer, 2008. http://dx.doi.org/10.1515/9781571138019-011.

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"4: “Ein Mann sucht sein Vaterland”?: Die Kapuzinergruft and the Confrontation with History". En Joseph Roth's March into History, 167–96. Boydell and Brewer, 2008. http://dx.doi.org/10.1515/9781571138019-007.

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"Acknowledgments". En Joseph Roth's March into History, vii—viii. Boydell and Brewer, 2008. http://dx.doi.org/10.1515/9781571138019-001.

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"Contents". En Joseph Roth's March into History, v—vi. Boydell and Brewer, 2008. http://dx.doi.org/10.1515/9781571138019-toc.

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"2: “Die Welt ist irrsinnig”: The Early Novels: Das Spinnennetz, Hotel Savoy, Die Rebellion". En Joseph Roth's March into History, 46–102. Boydell and Brewer, 2008. http://dx.doi.org/10.1515/9781571138019-005.

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"3: “. . . in Wahrheit . . . umgewandelte Realität”: Radetzkymarsch as Historical Novel". En Joseph Roth's March into History, 103–66. Boydell and Brewer, 2008. http://dx.doi.org/10.1515/9781571138019-006.

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"Conclusion". En Joseph Roth's March into History, 197–202. Boydell and Brewer, 2008. http://dx.doi.org/10.1515/9781571138019-008.

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"Frontmatter". En Joseph Roth's March into History, i—iv. Boydell and Brewer, 2008. http://dx.doi.org/10.1515/9781571138019-fm.

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"1: “Hinter dem Zaun”: Identity and Ideology". En Joseph Roth's March into History, 16–45. Boydell and Brewer, 2008. http://dx.doi.org/10.1515/9781571138019-004.

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Actas de conferencias sobre el tema "Marches de rotors"

Michelassi, V., P. Adami y F. Martelli. "An Implicit Algorithm for Stator-Rotor Interaction Analysis". En ASME 1996 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/96-gt-068.

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A simple time-accurate algorithm is presented for the computation of the unsteady stator-rotor interaction. The algorithm is based on the scalar approximate factorization method originally developed for the computation of complex three-dimensional steady flows. The method introduces a physical time step, used to march in time, and a numerical time step to iterate in between physical time steps. The method is formulated so as to take full advantage of the implicit formulation and provide an implicit treatment of the unsteady terms. A set of preliminary tests on a turbine stage, still in the experimental testing phase, proved the speed and accuracy of the method which was able to capture the essential features of a transonic stage.

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Corral, Roque y Juan Manuel Gallardo. "Verification of the Vibration Amplitude Prediction of Self-Excited LPT Rotor Blades Using a Fully Coupled Time-Domain Non-Linear Method and Experimental Data". En ASME Turbo Expo 2008: Power for Land, Sea, and Air. ASMEDC, 2008. http://dx.doi.org/10.1115/gt2008-51416.

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The vibration level of aerodynamically unstable low-pressure-turbine rotor blades has been assessed for the first time using two-different approaches. Both methods assume that the aerodynamic forcing is due solely to the self-excitation of the airfoil and that the vibration amplitude is saturated due to the non-linearity associated to the fir-tree dry friction, which is modeled using a simplified approach. To compensate for the limitations of the friction model several hypotheses need to be done, among them, the geometric similarity of the different configurations and that the aspect ratio of the rotor blades is high. The first approach, which is novel, assumes that the vibration amplitude is small enough and the unsteady aerodynamics associated to the airfoil motion may be computed using a frequency domain linearized Navier-Stokes solver. The vibration amplitude is obtained posing the energy balance between the energy exerted by the most unstable aerodynamic mode and the energy dissipated by dry friction. The second approach time marches simultaneously the Reynolds-Average Navier Stokes equations and a simple mass-spring non-linear model consistent with the mechanical model used in the first approach. This fully coupled non-linear, both in the aerodynamic and structural sides, flutter analysis is considered unique in its kind. It is demonstrated by means of a simplified, but consistent with typical low-pressure-turbine bladed-disk, model that both methods are equivalent. The first approach has been applied to several bladed-disks and the comparison with experimental data is good in overall.

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Fukuda, M., T. Yoshida, A. Iseda, H. Semba, E. Saito, M. Kitamura, T. Dohi et al. "700°C A-USC Technology Development in Japan". En AM-EPRI 2016, editado por J. Parker, J. Shingledecker y J. Siefert. ASM International, 2016. http://dx.doi.org/10.31399/asm.cp.am-epri-2016p0012.

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Abstract Since 2008, Japanese boiler, turbine and valve manufacturers, research institutes and utility companies have been working together to develop 700V A·USC technology, with support from the Japanese government. The key areas of discussion are technology development of high temperature materials such as nickel-based alloys and advanced 9Cr steels, and their application to actual power plants. At the EPRI conference in 2013, our report mainly focused on the development of fundamental material and manufacturing technology during the first five years of the project, and the preparation status of the boiler component test and turbine rotor test for the latter four years of the project. The boiler component test, using a commercially-operating boiler, began in May 2015 and is scheduled to be finished by the end of 2016. The turbine rotor test at 700°C with actual speed will be carried out from September 2016 to March 2017. At this year’s conference, we will: l) briefly summarize the development of fundamental material and manufacturing technology and 2) provide an update on the progress of the boiler component test and the turbine rotor test.

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BA, Samba, Jinsoo Kim, Prateek Goel, Hussein Sahli, Arun Chacko, Olakunle Olanubi, Steve Lojek y Loic Hoarau. "Expanding Downlink Capabilities Using Autonomous Directional Drilling with Rotary Steerable Systems". En ADIPEC. SPE, 2022. http://dx.doi.org/10.2118/211067-ms.

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Abstract Directional drilling is a major activity in today's oil and gas industry, as most wells currently being drilled are directional wells. The complexity of the wells being drilled today creates the greatest risk and most promising scenarios for proper planning and implementation. The Autonomous Directional Drilling system includes an automated directional drilling advisor application that provides real-time working trajectories updates, steering recommendations, and downlink commands for rotary steerable system (RSS) tools. This DD Advisor system can be used in any type of well from start to finish by automatically providing the next sequence of actions at each survey point and carefully monitoring the steering responses to advise important actions to be taken. DD Advisor leverages the downhole closed-loop control capabilities to reduce the amount of intervention needed from surface. DD Advisor enables directional drilling with minimal human intervention either from the rig or from the office, taking advantage of the outstanding digitalization platform. DD Advisor with RSS capabilities is now deployed in the field and has been used in more than fifty different wells. These operations included successfully using the steering recommendations and sending the automated downlinks via software and hardware automated downlinking solutions. This operation was quite challenging and required automatically finding the optimum trajectory path with steering capability constraints, rate of penetration constraints, target deviation constraints, number of downlinks constraints, and minimizing risks to avoid costly failures. This paper presents a novel technical approach for automatically making directional drilling decisions. Autonomous Directional Drilling recently (March 2022) won a Houston Offshore Technology Conference technology award.

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Thys, Maxime, Valentin Chabaud, Thomas Sauder, Lene Eliassen, Lars O. Sæther y Øyvind B. Magnussen. "Real-Time Hybrid Model Testing of a Semi-Submersible 10MW Floating Wind Turbine and Advances in the Test Method". En ASME 2018 1st International Offshore Wind Technical Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/iowtc2018-1081.

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This article presents the Real-Time Hybrid Model (ReaTHM®) tests that were performed on a 10-MW semi-submersible floating wind turbine in the Ocean Basin at SINTEF Ocean in March 2018. The ReaTHM test method was used for the model tests to circumvent the limitations encountered when performing model tests with wind and waves. The physical model was subject to physical waves, while the rotor and tower loads were simulated in real-time and applied on the model by use of a cable-driven parallel robot. Recent advances in the ReaTHM test method allowed for extended testing possibilities and load application up to the 3p frequency and the first tower bending frequency.

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Scalzo, A. J., R. L. Bannister, M. DeCorso y G. S. Howard. "Evolution of Heavy-Duty Power Generation and Industrial Combustion Turbines in the United States". En ASME 1994 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1994. http://dx.doi.org/10.1115/94-gt-488.

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This paper reviews the evolution of heavy-duty power generation and industrial combustion turbines in the United States from a Westinghouse Electric Corporation perspective. Westinghouse combustion turbine genealogy began in March of 1943 when the first wholly American designed and manufactured jet engine went on test in Philadelphia, and continues today in Orlando, Florida with the 160 MW, 501F Advanced Combustion Turbine. In this paper, advances in thermodynamics, materials, cooling, and unit size will be described. Many basic design features such as two-bearing rotor, cold-end drive, can-annular internal combustors, CURVIC2 clutched turbine discs, and tangential exhaust struts have endured successfully for over 40 years. Progress in turbine technology includes the clean coal technology and advanced turbine systems initiatives of the U.S. Department of Energy.

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Tanaka, Koichi, Makoto Yoshida, Toshifumi Kubo, Hirofumi Terazono y Sazo Tsuruzono. "Development and Evaluation of Ceramic Components for Small Gas Turbine Engine". En ASME Turbo Expo 2000: Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/2000-gt-0531.

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The 300kW class CGT project in Japan administered by the New Energy and Industrial Technology Development Organization (NEDO) under the sponsorship of the Ministry of International Trade and Industry (MITI) was completed in March, 1999 after 11 years. The purposes of the project were energy conservation and environmental protection. The CGT302 group of the CGT project, in cooperation with Kawasaki Heavy Industries, Ltd. (KHI), achieved all of the project targets. The targets included the turbine inlet temperature (TIT) of 1350°C, a thermal efficiency of 42%, emissions below 70ppm, and a 1000hr engine durability test carried out at 1200°C1). To achieve such targets Kyocera has been developing various ceramic components such as large-sized stationary components, monolithic rotors and ceramic shrouds with abradable seal. These components have been successfully fabricated with SN281 and SN282. Damage was caused as a result of contact between the turbine blades and the shrouds. In order to reduce such damages, the shroud has been modified to incorporate an abradable material newly developed for this application, and an engine test has been carried out successfully with no damage. For practical use, the greatest concern is the durability of ceramic components. The ceramic components were evaluated in a 1000hr long term durability test. There were, however, some troubles for the GGT rotors and the engines were broken when the durability tests were carried out. Finally, only the combustor survived the 1000hr engine test at 1200°C. The material characteristics of the survived combustor along with other broken components were analyzed after the long-term engine tests. The test results revealed no obvious change in mechanical properties nor in blade shape. In this paper, the development of selected components is presented along with the evaluation results of components exposed to the long-term engine tests.

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Kidwell, J. R. y D. M. Kreiner. "AGT 101: Advanced Gas Turbine Technology Update". En ASME 1985 International Gas Turbine Conference and Exhibit. American Society of Mechanical Engineers, 1985. http://dx.doi.org/10.1115/85-gt-177.

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The Garrett/Ford AGT101 program has made significant progress during 1984 in ceramic component and engine test bed development, including initial ceramic engine testing. All ceramic components for the AGT101 [1644K (2500F)] engine are now undergoing development. Ceramic structures have been undergoing extensive analysis, design modification, and rig testing. AGT101 [1644K (2500F)] start capability has been demonstrated in rig tests. Also, 1644K (2500F) steady-state testing has been initiated in the test rigs to obtain a better understanding of ceramics in that environment. The ceramic turbine rotor has progressed through cold spin test 12,040 rad/sec (115,000 rpm) and hot turbine rig test, and is currently in initial phases of engine test. Over 400 hours of engine testing is expected by March, 1985, including approximately 150 hours of operation and 50 starts on the 1422K (2100F) engine. All activities are progressing toward 1644K (2500F) engine testing in mid 1985.

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Regnier, Bradley, Joel Baden, Albert Brand, Patrick Lindauer, Joshua O'Neil y John Schillings. "Cold Weather Testing of the Bell 525 Relentless". En Vertical Flight Society 76th Annual Forum & Technology Display. The Vertical Flight Society, 2020. http://dx.doi.org/10.4050/f-0076-2020-16362.

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In the winter months of January-March 2019, two Bell 525 test aircraft completed cold weather testing at Yellowknife Canada, some 1900 nm from Bell’s Flight Research Center in Arlington, TX. Testing was aimed at demonstrating aircraft stability, performance, and flight characteristics at extreme temperatures as required by CFR Part 29. Since regulations only permit limited temperature extrapolation, the cold temperature tests must include the limit of forward speed in a dive (VNE), and assessments of performance, controllability, autorotation, and static stability. This paper describes some of the unique environmental conditions and factors that any rotorcraft development program could experience in cold weather testing. The paper also gives a technical description of the required testing, where arctic conditions reached as low as -40° F or C (the temperature scales are the same at this temperature). Testing exposed the aircraft to overnight cold-soaks that brought fluids, seals, windshields, electronics, and elastomeric bearings to their low temperature specification, all at the same time. For the 525, test results demonstrated that the aircraft was ready for start-up and operation in extreme cold. The criteria necessary for meeting certification requirements in cold weather were also demonstrated in the series of tests and showed that the rotor was free from any adverse effects due to aerodynamic compressibility, had low vibration, acceptable loads and was free from any instability, even at speeds greater than VNE.

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Kosing, O. E., R. Scharl y H. J. Schmuhl. "Design Improvements of the EJ 200 HP Compressor: From Design Verification Engine to a Future All Blisk Version". En ASME Turbo Expo 2001: Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/2001-gt-0283.

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The EJ 200 engine powers the Eurofighter / Typhon combat aircraft and is being built by the four nations UK (RR), Germany (MTU), Italy (FIAT AVIO) and Spain (ITP). The engine is capable of 60 kN dry thrust and 90kN reheat thrust with a 15% built in growth potential. The specific thrust to weight ratio is ≈ 10 and the overall pressure ratio 26. MTU’s 33% work - share package contains the development of the three stage LP Compressor, the five stage HP Compressor and the Digital Engine Control Unit. This paper concentrates on the five stage axial HP Compressor. It describes the major design changes from the very first design verification engine (DVE) to a future all blisk version. It first provides a brief historical overview of the major design improvements which are then discussed in detail. The rotor concept is discussed with respect to life, weight, material and repair. The development of the casing to improve the tip clearance behaviour, the containment and the protection against titanium fire is outlined. The stator concept is described in connection with an intense cost reduction program. The HP Compressor has successfully completed testing and flight clearance has been approved for all standards. Thus far the HPC has accumulated more than 16500 hours total engine experience and over 1040 Eurofighter flights. The production engine manufacturing is in progress, with the first engine to be delivered in March 2001.

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Informes sobre el tema "Marches de rotors"

Malcolm, D. J. y A. C. Hansen. WindPACT Turbine Rotor Design, Specific Rating Study; Period of Performance: June 29, 2000--March 1, 2003. Office of Scientific and Technical Information (OSTI), noviembre de 2003. http://dx.doi.org/10.2172/15005921.

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Cobb, J. T. Jr. Coal desulfurization in a rotary kiln combustor. Final report, March 15, 1990--July 31, 1991. Office of Scientific and Technical Information (OSTI), septiembre de 1992. http://dx.doi.org/10.2172/10110381.

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Collins, Matthew, John Jorgensen y Keely Murdock. Integrated Status and Effectiveness Monitoring Program, Entiat River Status and Trend Snorkel Surveys and Rotary Smolt Trap Operations in Nason Creek, March 2007 through March 2008. Office of Scientific and Technical Information (OSTI), marzo de 2008. http://dx.doi.org/10.2172/941527.

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Johnson, Peter N. y Michael D. Rayton. Enumeration of Juvenile Salmonids in the Okanogan Basin Using Rotary Screw Traps, Performance Period: March 15, 2006 - July 15, 2006. Office of Scientific and Technical Information (OSTI), mayo de 2007. http://dx.doi.org/10.2172/947613.

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Donoghue, E. M., G. L. Benson y J. L. Chamberlain. Sustainable production of wood and non-wood forest products: Proceedings of IUFRO Division 5 Research Groups 5.11 and 5.12, Rotorua, New Zealand, March 11–15, 2003. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station, 2004. http://dx.doi.org/10.2737/pnw-gtr-604.

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