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Relevant bibliographies by topics / Alford Force

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Academic literature on the topic 'Alford Force'

Author: Grafiati

Published: 4 June 2021

Last updated: 19 February 2022

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Journal articles on the topic "Alford Force"

1

Spakovszky, Z. S. "Analysis of Aerodynamically Induced Whirling Forces in Axial Flow Compressors." Journal of Turbomachinery 122, no. 4 (2000): 761–68. http://dx.doi.org/10.1115/1.1312801.

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A new analytical model to predict the aerodynamic forces in axial flow compressors due to asymmetric tip-clearance is introduced. The model captures the effects of tip-clearance induced distortion (i.e., forced shaft whirl), unsteady momentum-induced tangential blade forces, and pressure-induced forces on the spool. Pressure forces are shown to lag the tip-clearance asymmetry, resulting in a tangential (i.e., whirl-inducing) force due to spool pressure. This force can be of comparable magnitude to the classical Alford force. Prediction and elucidation of the Alford force is also presented. In

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2

Ehrich, F. "Rotor Whirl Forces Induced by the Tip Clearance Effect in Axial Flow Compressors." Journal of Vibration and Acoustics 115, no. 4 (1993): 509–15. http://dx.doi.org/10.1115/1.2930379.

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It is now widely recognized that destabilizing forces, tending to generate forward rotor whirl, are generated in axial flow turbines as a result of the nonuniform torque induced by the nonuniform tip-clearance in a deflected rotor—the so called Thomas/Alford force (Thomas, 1958, and Alford, 1965). It is also recognized that there will be a similar effect in axial flow compressors, but qualitative considerations cannot definitively establish the magnitude or even the direction of the induced whirling forces—that is, if they will tend to forward or backward whirl. Applying a “parallel compressor

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3

Storace, A. F., D. C. Wisler, H. W. Shin, et al. "Unsteady Flow and Whirl-Inducing Forces in Axial-Flow Compressors: Part I—Experiment." Journal of Turbomachinery 123, no. 3 (2000): 433–45. http://dx.doi.org/10.1115/1.1378299.

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An experimental and theoretical investigation has been conducted to evaluate the effects seen in axial-flow compressors when the centerline of the rotor is displaced from the centerline of the static structure of the engine. This creates circumferentially nonuniform rotor-tip clearances, unsteady flow, and potentially increased clearances if the rotating and stationary parts come in contact. The result not only adversely affects compressor stall margin, pressure rise capability, and efficiency, but also generates an unsteady, destabilizing, aerodynamic force, called the Thomas/Alford force, wh

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4

Martinez-Sanchez, M., B. Jaroux, S. J. Song, and S. Yoo. "Measurement of Turbine Blade-Tip Rotordynamic Excitation Forces." Journal of Turbomachinery 117, no. 3 (1995): 384–92. http://dx.doi.org/10.1115/1.2835673.

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This paper presents results of a program to investigate the magnitude, origin, and parametric variations of destabilizing forces that arise in high power turbines due to blade-tip leakage effects. Five different unshrouded turbine configurations and one configuration shrouded with a labyrinth seal were tested with static offsets of the turbine shaft. The forces along and perpendicular to the offset were measured directly with a dynamometer, and were also inferred from velocity triangles and pressure distributions obtained from detailed flow surveys. These two routes yielded values in fair agre

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5

Dellinger, Joe A., Bertram Nolte, and John T. Etgen. "Alford rotation, ray theory, and crossed‐dipole geometry." GEOPHYSICS 66, no. 2 (2001): 637–47. http://dx.doi.org/10.1190/1.1444954.

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Two generalizations of Alford rotation have been proposed for processing 2 × 2-component data containing nonorthogonal split shear waves: singular value decomposition (SVD) and eigenvector‐eigenvalue decomposition (EED). Using a simple crossed‐dipole synthetic model, we demonstrate that the physical model behind the EED method is invalid. It incorrectly assumes that a vector source aligned with the particle motion of an anisotropic pure mode will excite only that one mode. Ray theory shows that a vector point‐force source embedded in a homogeneous anisotropic medium instead excites all those m

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6

Cheng, Mei, Guang Meng, and Bingyu Wu. "Nonlinear dynamics of a rotor-ball bearing system with Alford force." Journal of Vibration and Control 18, no. 1 (2011): 17–27. http://dx.doi.org/10.1177/1077546311405701.

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7

Ehrich, F. F., Z. S. Spakovszky, M. Martinez-Sanchez, et al. "Unsteady Flow and Whirl-Inducing Forces in Axial-Flow Compressors: Part II—Analysis." Journal of Turbomachinery 123, no. 3 (2000): 446–52. http://dx.doi.org/10.1115/1.1370165.

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An experimental and theoretical investigation was conducted to evaluate the effects seen in axial-flow compressors when the centerline of the rotor becomes displaced from the centerline of the static structure of the engine, thus creating circumferentially nonuniform rotor-tip clearances. This displacement produces unsteady flow and creates a system of destabilizing forces, which contribute significantly to rotor whirl instability in turbomachinery. These forces were first identified by Thomas (1958. Bull. AIM, 71, No. 11/12, pp. 1039–1063.) for turbines and by Alford (1965. J. Eng. Power, Oct

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8

Colding-Jorgensen, J. "Prediction of Rotor Dynamic Destabilizing Forces in Axial Flow Compressors." Journal of Fluids Engineering 114, no. 4 (1992): 621–25. http://dx.doi.org/10.1115/1.2910076.

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It has been shown by Thomas (1958) and Alford (1965), that axial flow turbo-machinery is subject to rotor dynamic destabilizing gas forces produced by the circumferential variation of blade-tip clearance when the rotor is whirling. However, the magnitude and direction of these forces have yet to be clarified. For example, it is still uncertain, under which circumstances the rotor whirl direction will be forward, and when it will be backward, with respect to the rotation. In the present paper, a simple analysis of the perturbed flow in an axial compressor stage with whirling rotor is presented,

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9

Yang, Wenjun, Huiqun Yuan, Li Hui, and Kaifeng Zhang. "Dynamic Analysis of Flexible Shaft and Elastic Disk Rotor System Based on the Effect of Alford Force." Shock and Vibration 2019 (February 14, 2019): 1–13. http://dx.doi.org/10.1155/2019/3545939.

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Taken the flexible shaft and elastic disk rotor system as the research object, vibration differential equations are established by the modal synthesis method. Based on the Runge–Kutta method of direct integration, dynamic equations are solved successfully. Then, the effects of Alford force caused by the airflow excitation are researched on the stability and dynamic response. The results show modal vibration of the disk takes a great effect on the coupled natural frequency of shaft transverse vibration in the high rotational speed region. The effect of shaft-disk coupling makes rotor frequency

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10

Gildea, Niall. "Aliens in Cambridge." Derrida Today 10, no. 2 (2017): 216–36. http://dx.doi.org/10.3366/drt.2017.0157.

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In 1833, Henry Alford, a Cambridge don, writes to an ‘earthly friend’ entreating help to cure his intolerance for some of his fellow Cantabrigians. He is, subsequently, visited in dreams by an unearthly friend. One hundred and sixty years later, John Holloway writes Civitatula, a poem celebrating Cambridge University's history. The year before, Holloway had been busy protesting the award of Derrida's Honorary Doctorate there. Reflecting on the turbulence of 1968, Holloway's narrator suggests a Cantabrigian encounter with extra-terrestrials as tonic to this agitation. These oneiric visitations

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Dissertations / Theses on the topic "Alford Force"

1

Yoo, Soomyung. "Modeling of Alford force and tip clearance flow for turbine blades." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/47315.

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2

Cai, Zhemin Mechanical &amp Manufacturing Engineering Faculty of Engineering UNSW. "Turbo-generator responses due to the Alford force, the steam excitation force and the dominant unbalanced magnetic pull." Publisher:University of New South Wales. Mechanical & Manufacturing Engineering, 2009. http://handle.unsw.edu.au/1959.4/43544.

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In turbomachinery, extra excitation forces may result from non-idealised operation conditions and may sometime cause excessive vibrations and unsteady rotor motions. The goal of this thesis is to investigate the effects of such excitation forces. The extra excitation forces investigated here are the Thomas/Alford force due to the blade tip clearance change, the steam excitation force caused by the variation of inlet steam speed and state blade trailing wake and the dominant magnetic pull force due to dynamic eccentricity of the rotor. The main research results in this thesis include: (1) The

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3

Sawyer, Alexandre. "La promotion de la langue française dans les forces armées canadiennes: L'exemple des Généraux Jean Victor Allard et Jacques Alfred Dextraze." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28389.

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Cette thèse examine l'évolution de la situation des francophones et de leur langue dans les Forces armées canadiennes pour la période 1945-1977. Ce travail évalue la contribution dans ce domaine des deux premiers chefs d'état-major canadiens-français, Jean Victor Allard et Jacques Alfred Dextraze. Aucune autre étude académique n'a traité spécifiquement de cette question. Au sortir de la Seconde Guerre mondiale, la présence des militaires canadiens-français est modeste. Ils ne représentent que 6,9% de tous les officiers et 15,3% des hommes de troupe, alors que leur poids démographique dans la p

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4

Wurl, William M. "Admiral William S. Benson and the American Tradition of Sea Power." Kent State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=kent1258055271.

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Books on the topic "Alford Force"

1

Jean-Claude, Monier, ed. Alfred Fouillée: L'idée-force de la démocratie. Michalon éditeur, 2015.

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2

Trendell, John. Colonel Bogey to the fore: A biography of Kenneth J. Alford. Blue Band Magazine, 1991.

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3

T, Foley Robert, ed. Alfred von Schlieffen's military writings. Frank Cass, 2003.

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4

Emezue, Sydney. The last flight out: Reminiscences of a Biafran air force pilot : (the Alfred Anowai's story). Moorhen Books, 2011.

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5

Knegt, Daniel. Fascism, Liberalism and Europeanism in the Political Thought of Bertrand de Jouvenel and Alfred Fabre-Luce. Amsterdam University Press, 2017. http://dx.doi.org/10.5117/9789462983335.

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Despite the recent rise in studies that approach fascism as a transnational phenomenon, the links between fascism and internationalist intellectual currents have only received scant attention. This book explores the political thought of Bertrand de Jouvenel and Alfred Fabre-Luce, two French intellectuals, journalists and political writers who, from 1930 to the mid-1950s, moved between liberalism, fascism and Europeanism. Daniel Knegt argues that their longing for a united Europe was the driving force behind this ideological transformation-and that we can see in their thought the earliest stage

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6

Koeppen, Werner. Herbst 1941 im "Führerhauptquartier": Berichte Werner Koeppens an seinen Minister Alfred Rosenberg. Bundesarchiv, 2002.

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Pallast, Lienhard. Jesuskindchen klein, mach die Wehrmacht rein: Ein offener Brief an Alfred NevenDumont. L. Pallast, 1999.

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8

B, Hattendorf John, ed. Mahan on naval strategy: Selections from the writings of Rear Admiral Alfred Thayer Mahan. Naval Institute Press, 1991.

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9

Mock, Alfred. Bail out: Alfred Mock's World War II story as told to Christopher P. Gregoire. C.P. Gregoire, 1987.

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Foley, Robert. Alfred Von Schlieffen's Military Writings. Frank Cass, 2002.

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Book chapters on the topic "Alford Force"

1

Baer, George. "Alfred Thayer Mahan and the Utility of US Naval Forces Today." In The Changing Face of Maritime Power. Palgrave Macmillan UK, 1999. http://dx.doi.org/10.1057/9780230509610_2.

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2

Stowe, Harriet Beecher. "Fore Shado Wings." In Uncle Tom's Cabin. Oxford University Press, 2008. http://dx.doi.org/10.1093/owc/9780199538034.003.0027.

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Two days after this, Alfred St. Clare and Augustine parted; and Eva, who had been stimulated, by the society of her young cousin, to exertions beyond her strength, began to fail rapidly. St. Clare was at last willing to call in medical advice,—a thing from...

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3

Seligmann, Matthew S. "Britain and Economic Warfare in German Naval Thinking in the Era of the Great War." In Economic Warfare and the Sea. Liverpool University Press, 2020. http://dx.doi.org/10.3828/liverpool/9781789621594.003.0011.

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Under the leadership of Alfred von Tirpitz, the German navy concentrated on building a battle fleet based in the North Sea rather than cruisers designed for operations in distant waters. This has led many historians to assume that commerce warfare (Handelskrieg) played no real part in German preparations for war against Britain before 1914. This chapter disputes this analysis. It shows that Germany’s naval planners in the Admiralstab believed that by converting merchant ships into auxiliary cruisers and using them to attack British commerce on the high seas the German navy would be able to cause considerable damage to British shipping and so force the Royal Navy to divert forces from the main theatre of war to distant oceans. It goes on to examine the reality of this plan during the First World War.

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4

Gerard, Philip. "Confederate Gibraltar." In The Last Battleground. University of North Carolina Press, 2019. http://dx.doi.org/10.5149/northcarolina/9781469649566.003.0040.

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An immense sand fort guards the entrance to the Cape Fear River and the fairway to Wilmington, the last major open port of the Confederacy, through which blockade runners supply vital materiel for Gen. Lee’s Army of Northern Virginia. On Christmas Eve 1864, a U.S. Navy armada unleashes the heaviest bombardment in history on the fort, in advance of landing 6,500 assault troops. But the U.S. commander, Maj. Gen. Benjamin F. Butler, falters, and only 2,300 troops make it ashore in roughening weather. They are stranded on the cold beach overnight without shelter. In the morning, the fleet sails away. Just three weeks later an even more powerful assault force returns, including USCT, who will play a crucial role in the battle. This assault is led by Brig. Gen. Alfred Terry and after six hours of heavy hand-to hand fighting forces the surrender of the fort.

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5

Howe, Andrew. "Partial Rehabilitation: Task Force and the Case of Billy Mitchell." In ReFocus: The Films of Delmer Daves. Edinburgh University Press, 2016. http://dx.doi.org/10.3366/edinburgh/9781474403016.003.0010.

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Andrew Howe provides an account of one of Daves’ war films. Task Force is a biopic of General Billy Mitchell who, during the 1920s, tirelessly advocated for the concept of the aircraft carrier as the future of naval warfare. In his analysis, Howe posits three central figures: Daves as writer-director, Billy Mitchell as historical inspiration, and lead-actor Gary Cooper, who plays Mitchell’s fictional treatment in the film, Jonathan L. Scott. The chapter situates its analysis of ‘Mitchell’ within the context of the early Cold War years and of the Hollywood of the time. In the case of the latter, it discusses Hollywood’s post-War obsession with the subject of aerial warfare. In contrast to other contributors in this collection, Howe suggests Daves’ greater quality was as a writer, rather than a director, and ranks his best scripting efforts – Task Force included – alongside those of Alfred Hitchcock and Nicholas Ray.

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Gerard, Philip. "January 1865." In The Last Battleground. University of North Carolina Press, 2019. http://dx.doi.org/10.5149/northcarolina/9781469649566.003.0001.

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In early 1865, the Civil War collapses on North Carolina: Armies of the United States converge from the east (New Bern) and the west (Maj. Gen. George Stoneman’s raiders) as Brig. Gen. Alfred Terry’s force assaults Fort Fisher and Maj. Gen. William T. Sherman begins his Final March from Georgia into the Carolinas. As the Confederate government flees Richmond for Greensboro, and Raleigh native Andrew Johnson ascends to the Presidency, North Carolina becomes the main stage of the war.

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Offer, Avner, and Gabriel Söderberg. "A Prize in ‘Economic Sciences’." In The Nobel Factor. Princeton University Press, 2019. http://dx.doi.org/10.23943/princeton/9780691196312.003.0003.

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This chapter discusses the significance of a Nobel Prize in economics. In a turbulent world, the prizes that Alfred Nobel endowed in 1895 shine as beacons of enduring value. They signal that effort, integrity, and success in pursuit of truth can earn mighty acclaim. In 1968, the Swedish central bank persuaded the Nobel Foundation to add a prize in economics, identical in all but name to those in science, literature, and peace. For a paltry investment, it extended the aura of Nobel authority to the discipline of economics. It was an entrepreneurial move worthy of Alfred Nobel himself. Like Nobel's invention of dynamite, the economic prize was a force with potential for good but also for harm. But how does one think of economics as science? Specialists in scientific method, practising economists, and Nobel Prize winners tell different stories. This matters when we look to economics for policy advice.

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Allan, Michael. "Education." In In the Shadow of World Literature. Princeton University Press, 2016. http://dx.doi.org/10.23943/princeton/9780691167824.003.0004.

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This chapter considers the pedagogical instantiation of literature as a disciplined practice, with particular emphasis on the arguments for reformed educational policy, often anchored in fears of fanaticism as a counterpart to the moral force of modernization. It discusses the role of education in the writings of colonial administrators Lord Cromer and Alfred Milner, both of whom associate learning to read with the cultivation of sensibilities necessary to the supposedly virtuous ends of liberal government. Drawing from distinctions between taʻlīm (instruction) and tarbiyah (cultivation), as well as opinions versus prejudice, the chapter examines the role of reading as part of a broader conceptualization of education, civic participation, and the colonial Egyptian state.

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Taylor, Jesse Oak. "Mourning Species." In Ecological Form. Fordham University Press, 2018. http://dx.doi.org/10.5422/fordham/9780823282128.003.0003.

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This chapter develops a reading practice for the Anthropocene by tracing the reflections on extinction that recur throughout Alfred Tennyson’s magisterial elegy, In Memoriam (1850). It asks how the poem’s treatment of extinction changes when it is read as an account of anthropogenic extinction, the decimation of species arising explicitly from human action and linked (both metaphorically and literally) to imperial conquest. In so doing, it traces the emergence of a new kind of human “species being,” that is, the human as geophysical force within the Earth system, which appears in the poem through extended metaphors linking human evolution to industrial processes and imperial conquest thus speaking to one of the most difficult (and controversial) challenges that the Anthropocene lays before the humanities: thinking the human in species terms. In the process, the chapter makes a case for elegy as both an ethical and political stance complement to conservation.

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10

Patterson, Anita. "The American Legacy of “Prufrock”." In T. S. Eliot Studies Annual. Liverpool University Press, 2017. http://dx.doi.org/10.5949/liverpool/9781942954286.003.0004.

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The essay cluster brings together leading Eliot and modernist scholars to commemorate the centenary of the publication of “The Love Song of J. Alfred Prufrock.” Together, they reexamine the circumstances surrounding the poem’s original publication, recontextualize its allusions, and reconstruct its reception over the past century. Patterson examines the American roots of Eliot’s ironic love song, often considered through the lenses of European poetry and philosophy. Dickey returns to the poem’s early reception to challenge the now established narrative that “Prufrock” shocked early readers, showing how often his contemporaries associated the poem with Decadent or Aesthetic precedents. Ricks returns to the poem’s first publication in Poetry Magazine to understand how the poem’s first readers would have encountered the text and how this context would have mediated the reader’s experience. Cuda situates Eliot’s poem vis-à-vis current discourses on late modernism and demonstrates how lateness and belatedness feature centrally in the poem. Finally, Schuchard examines Eliot’s literary and religious allusions, showing that his allusive method is in full force even in his first poetic masterpiece.

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Conference papers on the topic "Alford Force"

1

Spakovszky, Z. S. "Analysis of Aerodynamically Induced Whirling Forces in Axial Flow Compressors." In ASME Turbo Expo 2000: Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/2000-gt-0418.

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A new analytical model to predict the aerodynamic forces in axial flow compressors due to asymmetric tip-clearance is introduced. The model captures the effects of tip-clearance induced distortion (i.e. forced shaft whirl), unsteady momentum-induced tangential blade forces and pressure induced forces on the spool. Pressure forces are shown to lag the tip-clearance asymmetry, resulting in a tangential (i.e. whirl-inducing) force due to spool pressure. This force can be of comparable magnitude to the classical Alford force. Prediction and elucidation of the Alford force is also presented. In par

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2

Myllerup, Claus M., and Graeme Keith. "Whirl Frequency Dependent Alford Forces in Axial Compressors." In ASME Turbo Expo 2004: Power for Land, Sea, and Air. ASMEDC, 2004. http://dx.doi.org/10.1115/gt2004-53096.

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Explicit closed form expressions are derived for the whirl frequency dependence of the Alford force in an axial compressor operating in steady-state away from the onset of rotating stall. The analysis includes the compressor flow dynamics using the Moore-Greitzer approximation. By asymptotic expansion in terms of the whirl orbit amplitude, expressions for the direct and cross-coupling impedance are obtained analytically. Several components in the cross-coupling impedance are shown to change phase as the whirl frequency transits the rotating stall frequency. This implies that for a given compre

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3

aus der Wiesche, Stefan, and Maximilian Passmann. "Analysis of Steam Turbine Blade Tip Excitation Forces by Means of Computational Fluid Dynamics and Experimental Cascade Results." In ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/gt2018-75179.

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A semi-empirical steam excitation force model is presented for freestanding unshrouded blades. The model is resting on a superposition of the classical Thomas-Alford cross forces and additional fluid derived forces. The additional fluid derived forces are caused by static pressure modifications in the blade tip region and large-scale redistributions of the inflow velocity caused by the varying tip gap width due to eccentricity. The empirical model parameters are obtained by means of computational fluid dynamics (CFD) and experimental turbine cascade results. The Thomas-Alford cross force contr

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4

aus der Wiesche, Stefan, Maximilian Passmann, and Reinhard Willinger. "Reduction of Turbine Blade Tip Leakage Losses and Excitation Forces by Passive Tip Injection." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-50120.

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The reduction of turbine blade-tip losses by means of passive tip injection was theoretically investigated. The analysis employed an analytical expression of the blade-tip discharge coefficient. The resulting blade-tip excitation forces (i. e. Thomas-Alford forces) were explicitly evaluated for unshrouded turbines with and without passive tip injection. It was found, that the Thomas-Alford coefficient for cross-force can substantially increase when the blade-tip gap was reduced. This observation can directly be explained on the basis of viscous flow effects through the gap, and it was in excel

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5

Lerche, Andrew H., Grant O. Musgrove, J. Jeffrey Moore, Chris D. Kulhanek, and Grant Nordwall. "Rotordynamic Force Prediction of an Unshrouded Radial Inflow Turbine Using Computational Fluid Dynamics." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95137.

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Cross-coupled forces due to bladed components, bearings and seals can contribute to destabilizing a rotor system and are an important input to the rotordynamic design of turbomachinery. Alford (1965) developed a simple formula for describing the cross-coupled mechanism of an unshrouded axial turbine stage. The high flow radial inflow turbine studied here can exhibit similar characteristics due to its long stage length. In this work, a transient computational solution is developed to predict cross-coupling stiffness of an unshrouded turbo-expander. The three-dimensional computational fluid dyna

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6

Ehrich, Fredric. "Rotor Whirl Forces Induced by the Tip Clearance Effect in Axial Flow Compressors." In ASME 1993 Design Technical Conferences. American Society of Mechanical Engineers, 1993. http://dx.doi.org/10.1115/detc1993-0177.

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Abstract It is now widely recognized that destabilizing forces, tending to generate forward rotor whirl, are generated in axial flow turbines as a result of the non-uniform torque induced by the non-uniform tip-clearance in a deflected rotor — the so called Thomas/Alford force (Thomas, 1958 and Alford, 1965). It is also recognized that there will be a similar effect in axial flow compressors, but qualitative considerations cannot definitively establish the magnitude or even the direction of the induced whirling forces — that is, if they will tend to forward or backward whirl. Applying a “paral

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7

Martinez-Sanchez, Manuel, Belgacem Jaroux, Seung Jin Song, and Soomyung Yoo. "Measurement of Turbine Blade-Tip Rotordynamic Excitation Forces." In ASME 1993 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1993. http://dx.doi.org/10.1115/93-gt-125.

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This paper presents results of a program to investigate the magnitude, origin and parametric variations of destabilizing forces which arise in high power turbines due to blade-tip leakage effects. Five different unshrouded turbine configurations and one configuration shrouded with a labyrinth seal were tested with static offsets of the turbine shaft. The forces along and perpendicular to the offset were measured directly with a dynamometer, and were also inferred from velocity triangles and pressure distributions obtained from detailed flow surveys. These two routes yielded values in fair agre

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8

Storace, A. F., D. C. Wisler, H. W. Shin, et al. "Unsteady Flow and Whirl-Inducing Forces in Axial-Flow Compressors: Part I — Experiment." In ASME Turbo Expo 2000: Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/2000-gt-0565.

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An experimental and theoretical investigation has been conducted to evaluate the effects seen in axial-flow compressors when the centerline of the rotor is displaced from the centerline of the static structure of the engine. This creates circumferentially non-uniform rotor-tip clearances, unsteady flow, and potentially increased clearances if the rotating and stationary parts come in contact. The result not only adversely affects compressor stall margin, pressure rise capability and efficiency but also generates an unsteady, destabilizing, aerodynamic force, called the Thomas/Alford force, whi

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9

Ehrich, F. F., Z. S. Spakovszky, M. Martinez-Sanchez, et al. "Unsteady Flow and Whirl-Inducing Forces in Axial-Flow Compressors: Part II — Analysis." In ASME Turbo Expo 2000: Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/2000-gt-0566.

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An experimental and theoretical investigation was conducted to evaluate the effects seen in axial-flow compressors when the centerline of the rotor becomes displaced from the centerline of the static structure of the engine, thus creating circumferentially non-uniform, rotor-tip clearances. This displacement produces unsteady flow and creates a system of destabilizing forces, which contribute significantly to rotor whirl instability in turbomachinery. These forces were first identified by Thomas (1958) for turbines and by Alford (1965) for jet engines. In Part I, the results from an experiment

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Kanki, Hiroshi, and Akinori Tanitsuji. "Stability of High Pressure Turbine Under Partial Admission Condition." In ASME 2005 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/detc2005-84774.

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Abstract:

Subsynchronous vibration of high-pressure steam turbine is one of the difficult problems to improve the reliability of power plant. Extensive work has been done to prevent the low frequency vibration of high-capacity steam turbine and most of the problems were practically solved[1][2]. In the future, we must build up theoretical approach to design a new turbine operating under the steam condition of high-temperature and high-pressure. To design such an advanced steam turbine, it is necessary to solve the effect of partial admission on control stage of the steam turbine. This paper describes th

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Reports on the topic "Alford Force"

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Nash, Gordon C. Alfred Theyer Mahan's Strategy of Forward Deployed Maritime Forces. Defense Technical Information Center, 1990. http://dx.doi.org/10.21236/ada440946.

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