TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Nipkau, Jens T1 - On the Influence of Strain Gauge Instrumentation on Blade Vibrations of Integral Blisk Compressor Rotors Applying a Discrete Model T2 - Proceedings of the ASME Turbo Expo 2009, presented at the 2009 ASME Turbo Expo, June 8 - 12, 2009, Orlando, Florida, USA Y1 - 2009 SN - 978-0-7918-4887-6 N1 - GT2009-59207 SP - 245 EP - 254 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Klauke, Thomas A1 - Kühhorn, Arnold A1 - Kober, Markus T1 - Application of a Newer Inter-Fiber-Failure Criteria on CFRPs in Aero Engine Development Y1 - 2010 ER - TY - CHAP A1 - Beirow, Bernd A1 - Osterrieder, Peter ED - Zingoni, Alphose T1 - Dynamic Investigations of TV Towers T2 - Structural engineering, mechanics, and computation, proceedings of the International Conference on Structural Engineering, Mechanics, and Computation, 2-4 April 2001, Cape Town, South Africa, Bd. 1 Y1 - 2001 SN - 0-08-043948-9 SP - 629 EP - 636 PB - Elsevier CY - Amsterdam ER - TY - GEN A1 - Kühhorn, Arnold A1 - Beirow, Bernd A1 - Schrape, Sven A1 - Golze, Mark A1 - Knöpke, Martin T1 - Simulation fluidgedämpfter Strukturschwingungen mittels partitionierter Fluid-Struktur-Kopplung T2 - Forum der Forschung Y1 - 2005 SN - 0947-6989 VL - 9 IS - 18 SP - 79 EP - 86 ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Klauke, Thomas T1 - Lokalisierungsphänomen bei Hochdruckverdichterschaufelscheiben KW - Schaufelscheiben KW - Hochdruckverdichter Y1 - 2006 ER - TY - CHAP A1 - Kühhorn, Arnold T1 - Flug-Triebwerkstechnik - innovative Studienrichtung an der BTU Cottbus unter Beteilugung von RRD, MTU und DLR T2 - Deutscher Luft- und Raumfahrtkongress 2006, Braunschweig, 06. bis 09. November 2006, Bd. 1 KW - Studienrichtung Triebwerkstechnik Y1 - 2006 SP - 593 EP - 596 PB - Dt. Ges. für Luft- und Raumfahrt CY - Bonn ER - TY - JOUR A1 - Kühhorn, Arnold A1 - Beirow, Bernd A1 - Klauke, Thomas T1 - Theoretische und experimentelle Untersuchungen von Schaufelschwingungen bei Verdichterintegralrädern KW - Schaufelschwingungen Y1 - 2006 ER - TY - THES A1 - Lenk, Olaf T1 - Charakterisierung und Anwendung von flächig periodischen Metall-Ringgeflechten KW - Geflecht KW - Metall Y1 - 2009 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:co1-opus-10148 ER - TY - GEN A1 - Zolochevsky, Alexander A1 - Galishin, A. A1 - Kühhorn, Arnold A1 - Springmann, Marcel T1 - Transversal Shear Effect in Moderately Thick Shells from Materials with Characteristics Dependent on the Kind of Stress State under Creep-Damage Conditions: Numerical Modeling Y1 - 2009 ER - TY - GEN A1 - Zolochevsky, Alexander A1 - Galishin, A. A1 - Kühhorn, Arnold A1 - Springmann, Marcel T1 - Transversal Shear Effect in Moderately Thick Shells from Materials with Characteristics Dependent on the Kind of Stress State under Creep-Damage Conditions: Theoretical Framework Y1 - 2009 ER - TY - CHAP A1 - Strehlau, Ulrik A1 - Kühhorn, Arnold A1 - Beirow, Bernd T1 - Numerische und experimentelle Untersuchungen realer Hochdruckverdichterschaufelscheiben in Integralbauweise Y1 - 2009 ER - TY - CHAP A1 - Kober, Markus A1 - Kühhorn, Arnold T1 - Auslegung und Optimierungsprozess einer Tragstruktur in Faserverbundbauweise unter Berücksichtigung moderner Versagenskriterien Y1 - 2009 ER - TY - GEN A1 - Springmann, Marcel A1 - Kühhorn, Arnold A1 - Kuna, M. A1 - Scherzer, M. T1 - Influence of Strain Localization on Parameter Identification Y1 - 2009 ER - TY - CHAP A1 - Springmann, Marcel A1 - Kühhorn, Arnold A1 - Filipiak, A. A1 - Hugler, Daniel A1 - Dufor, K.-H. T1 - Automatic generation and optimization of a simplified aircraft engine model using a graphical user interface and full parameterization Y1 - 2008 ER - TY - CHAP A1 - Strehlau, Ulrik A1 - Kühhorn, Arnold T1 - Schwingungsverhalten von Hochdruckverdichterschaufelscheiben in Integralbauweise (Blisk) unter Berücksichtigung höherer Schwingungsmoden, Erzeugung und Messung von Umlaufwellen, 3D-Geometrievermessung T2 - Deutscher Luft- und Raumfahrtkongress 2008, Darmstadt, 23. bis 25. September 2008, Bd. 1 Y1 - 2008 N1 - Document-ID: 81170 SP - 457 EP - 467 PB - Dt. Ges. für Luft- und Raumfahrt CY - Bonn ER - TY - CHAP A1 - Schrape, S. A1 - Kühhorn, Arnold A1 - Nipkau, Jens A1 - Beirow, Bernd T1 - Application of Aeroelastic Methods in Compressor Cascade Configurations Using Partitioned Code Coupling Y1 - 2008 ER - TY - CHAP A1 - Springmann, Marcel A1 - Kühhorn, Arnold T1 - Coupled thermal-multiphase flow analysis in quenching processes for residual stress optimization in compressor and turbine disks T2 - Proceedings of the ASME Pressure Vessels and Piping Conference - 2008, presented at 2008 ASME Pressure Vessels and Piping Conference, July 27 - 31, 2008, Chicago, Illinois, USA, Vol. 4 Y1 - 2008 SN - 978-0-7918-4827-2 SP - 147 EP - 156 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Springmann, Marcel A1 - Schlums, H. A1 - Kühhorn, Arnold T1 - Numerical simulation of quenching processes for residual stress optimization in compressor and turbine disks Y1 - 2008 ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Schrape, S. T1 - Development of a new Nickel-base Alloy 718Plus for Compressor and Turbine disks Y1 - 2007 ER - TY - CHAP A1 - Kober, Markus A1 - Kühhorn, Arnold A1 - Klauke, Thomas T1 - Auslegung einer Flanschverbindung aus faserverstärktem Kunststoff durch Optimierung der Faserorientierungen und Schichtdicken mit Hilfe von Altair HyperStudy unter Verwendung eines Wirkebenenbruchkriteriums als Nebenbedingung Y1 - 2007 ER - TY - CHAP A1 - Schrape, S. A1 - Kühhorn, Arnold A1 - Nipkau, Jens T1 - Determination of Aerodynamic Damping of Axial-Compressor-Blades Using A Bidirectional Fluid-Structure-Simulation T2 - 1st CEAS European Air and Space Conference 2007, Deutscher Luft- und Raumfahrtkongress 2007, 10 - 13 September 2007, Berlin, Germany, Bd. 1 Y1 - 2007 N1 - CEAS-2007-027 SP - 309 EP - 318 PB - Dt. Ges. für Luft- und Raumfahrt CY - Bonn ER - TY - CHAP A1 - Klauke, Thomas A1 - Kühhorn, Arnold A1 - Beirow, Bernd T1 - Blade Mistuning Induced Blisk Vibration T2 - 1st CEAS European Air and Space Conference 2007, Deutscher Luft- und Raumfahrtkongress 2007, 10 - 13 September 2007, Berlin, Germany, Bd. 1 Y1 - 2007 SP - 335 EP - 345 PB - Dt. Ges. für Luft- und Raumfahrt CY - Bonn ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Schrape, S. T1 - Influence of Air Flow on Blisk Vibration Behaviour T2 - 1st CEAS European Air and Space Conference 2007, Deutscher Luft- und Raumfahrtkongress 2007, 10 - 13 September 2007, Berlin, Germany, Bd. 5 Y1 - 2007 N1 - CEAS-2007-058 SP - 3127 EP - 3135 PB - Dt. Ges. für Luft- und Raumfahrt CY - Bonn ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Schrape, S. T1 - Blisk Vibration Phenomena in Consideration of Fluid Structure Interaction Y1 - 2007 ER - TY - CHAP A1 - Kober, Markus A1 - Klauke, Thomas A1 - Kühhorn, Arnold A1 - Lenk, Olaf T1 - Einbindung eines modernen Wirkebenenbruchkriteriums für faserverstärkte Kunststoffe in eine Parameteroptimierung mit Altair HyperStudy Y1 - 2006 ER - TY - CHAP A1 - Kober, Markus A1 - Kühhorn, Arnold A1 - Klauke, Thomas A1 - Lenk, Olaf T1 - Topology-Optimized Intermediate Casing of Aero Engine and Comparative Evaluation of Titanium and Composite Architecture in Terms of Load Capacity and Weight Reduction T2 - Proceedings of the ASME Turbo Expo 2008, presented at the 2008 ASME Turbo Expo, June 9 - 13, 2008, Berlin, Germany, Vol. 5, part A Y1 - 2008 SN - 978-0-7918-4315-4 N1 - GT2008-50644 SP - 69 EP - 79 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Schrape, S. T1 - A Discrete model to consider the influence of the air flow on blade vibrations of an intergral blisk compressor rotor T2 - Proceedings of the ASME Turbo Expo 2008, presented at the 2008 ASME Turbo Expo, June 9 - 13, 2008, Berlin, Germany, Vol. 5, part A Y1 - 2008 SN - 978-0-7918-4315-4 N1 - GT2008-50613 SP - 381 EP - 392 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Klauke, Thomas A1 - Kühhorn, Arnold A1 - Beirow, Bernd A1 - Parchem, Roland T1 - Blade Vibration Phenomena of HPC Bliscs Considering Manufacturing Effects and Strain Gauge Application T2 - Proceedings of the ASME Turbo Expo 2008, presented at the 2008 ASME Turbo Expo, June 9 - 13, 2008, Berlin, Germany, Vol. 5, part A Y1 - 2008 SN - 978-0-7918-4315-4 SP - 403 EP - 413 PB - ASME CY - New York, NY ER - TY - JOUR A1 - Nipkau, Jens A1 - Schrape, S. A1 - Beirow, Bernd A1 - Kühhorn, Arnold T1 - Bestimmung aeroelastischer Parameter einer Hochdruckverdichter Stufe mit Hilfe Fluid-Struktur gekoppelter Berechnungen Y1 - 2008 ER - TY - CHAP A1 - Nipkau, Jens A1 - Kühhorn, Arnold A1 - Schrape, S. T1 - Application of Fluid-Structure-Coupling for the Determination of Aeroelastic Parameters of a High-Pressure-Compressor-Blisk-Stage Y1 - 2008 ER - TY - CHAP A1 - Zuchlinski, André A1 - Kühhorn, Arnold T1 - Strukturelle Optimierung der Aufhängung von heckinstallierten und parametrisierten Turbofantriebwerksmodellen Y1 - 2010 ER - TY - CHAP A1 - Strehlau, Ulrik A1 - Kühhorn, Arnold T1 - Research of higher modes E3E/1 stage 1 demonstrator blisk Y1 - 2007 ER - TY - CHAP A1 - Schrape, S. A1 - Kühhorn, Arnold A1 - Nipkau, Jens T1 - Determination of Aerodynamic Damping of Axial-Compressor-Blades using Fluid-Structure-Interaction Methods Y1 - 2007 ER - TY - CHAP A1 - Hönisch, Peter A1 - Kühhorn, Arnold T1 - Experimentelle und numerische Untersuchungen des Schwingungsverhaltensrealer Radialturbinenlaufräder in Integralbauweise (Blisk) im Hinblick auf Verstimmung und Lokalisierung Y1 - 2011 ER - TY - CHAP A1 - Kühhorn, Arnold A1 - Strehlau, Ulrik T1 - Verstimmungsuntersuchungen am Laufrad (Blisk) eines modernenFlugtriebwerk-Hochdruckverdichters Y1 - 2011 ER - TY - THES A1 - Strehlau, Ulrik T1 - Schaufelschwingungen realer integraler Verdichterlaufräder bei zusätzlicher Berücksichtigung höherer Moden N2 - Verbunden mit der Forderung nach immer leistungsfähigeren, umweltfreundlicheren und hinsichtlich des Treibstoffverbrauchs effizienteren Triebwerken kommen in der jüngeren Vergangenheit mehr und mehr Verdichterlaufräder in Integralbauweise zum Einsatz.Wesentlicher Vorteil der integralen Bauteile ist eine, im Vergleich zur herkömmlichen Bauweise von Laufrädern mit gesteckten Schaufeln, deutliche Gewichtsreduktion. Diese ergibt sich einerseits aus der für die Blisk-Bauweise nicht mehr notwendigen, aufwändigen und massiven Schaufel-Scheibe-Fußkonstruktion sowie andererseits aus einem günstigeren Kraftfluss, der die Fliehkräfte der Schaufeln direkt in die Scheibe leitet. Da hierbei im Scheibenrandbereich Material eingespart wird, ist es möglich die Scheibe insgesamt leichter zu gestalten. Somit sind höhere Drehzahlen der Hochdruckverdichterwelle möglich, was zu höheren Druckverhältnissen führt. Unter der Maßgabe eines gleichen Druckverhältnisses für den Verdichter insgesamt, kann die Anzahl der Schaufeln der Laufräder reduziert oder es können gar ganze Verdichterstufen eingespart werden.Demgegenüber treten jedoch Phänomene, die durch ein unterschiedliches strukturdynamisches Verhalten der Schaufeln untereinander verursacht werden, bei Blisks besonders hervor. Grund dafür ist die fehlende Reibung an den in der konventionellen Bauweise vorhandenen formschlüssigen Kontaktstellen zwischen den Schaufeln und der Scheibe. Daher ist die mechanische Dämpfung für Laufräder in Integralbauweise deutlich kleiner als für vergleichbare Laufräder mit gesteckten Schaufeln.Mit zahlreichen numerischen Berechnungen und Experimenten an einer Rotorstufe aus einem im heutigen Triebwerksbau üblichen Hochdruckverdichter wird das strukturdynamische Verhalten diskutiert, wobei neben den drei Grundmodenfamilien wie erster und zweiter Biegung sowie der ersten Torsion auch höhere Modenfamilien untersucht werden. Grundlage für die numerischen Untersuchungen des verstimmten Rechenmodells sind schaufelindividuelle Verstimmungsmessungen, aus denen Parameter für den Abgleich des unverstimmten FE-Modells hin zum verstimmten FEModell extrahiert werden. Dieser Abgleich führt zu einem verstimmten Rechenmodell, welches die dynamischen Eigenschaften des realen Systems widerspiegelt.Unter der Annahme, dass die Verstimmung maßgeblich von Geometrievariationen der Schaufeln untereinander geprägt ist, wird eine 3D-Geometrievermessung ebenfalls mit dem Ziel durchgeführt, ein verstimmtes Modell zu erzeugen, welches das gemessene, strukturdynamische Verhalten der realen Struktur wiedergibt. Jedoch ergeben sich bisher zwischen den Berechnungsergebnissen des geometrieangepassten Modells und Messungen an der realen Blisk deutliche Unterschiede.Mittels einer neuartigen Methodik zur Einteilung von Eigenfrequenzen in Modenfamilien werden in dieser Arbeit Größen vorgestellt, die Rückschlüsse über die Sensitivität einer Modenfamilie gegenüber einer möglichen Verstimmung zulassen. Die Einteilung der Eigenfrequenzen und dazugehöriger Eigenformen erfolgt anhand strukturdynamischer Gesichtspunkte wie z.B. der Verzerrungsenergieverteilung auf den Schaufel- und Scheibenanteil oder anhand des modalen Vergleichskriteriums (MAC).Kernpunkt dieser Arbeit bildet die experimentelle Erregung und Messung von Umlaufwellen. Hierbei werden im Frequenzbereich gesplitteter Eigenfrequenzen des verstimmten Systems stehende sowie mit der Erregung und gegen die Erregung umlaufende erzwungene Schwingformen nachgewiesen. In diesem Zusammenhang wird ein Kriterium eingeführt, welches stehende und drehende Schwingformen quantitativ unterscheidet. Der Vergleich experimenteller Ergebnisse mit numerischen Berechnungen zeigt eine gute Übereinstimmung für die analysierten erzwungenen Schwingformen.Ein in der jüngeren Vergangenheit in Bezug auf zyklisch rotationssymmetrische Strukturen vermehrt untersuchtes Phänomen, das so genannte Frequency-Veering, wird in dieser Arbeit ausführlich experimentell untersucht. Zwei Frequency-Veering Bereiche zeigen sich an der untersuchten Blisk im Frequenzbereich höherer Modenfamilien. Hierbei ergibt sich keine größere Sensibilität der Struktur gegenüber ihrer Verstimmung. KW - Blisk KW - Schaufelschwingung KW - Lokalisierung KW - Geometrievermessung KW - Umlaufwelle Y1 - 2011 SN - 978-3-8440-0491-5 PB - Shaker Verlag CY - Aachen ER - TY - GEN A1 - Kober, Markus A1 - Kühhorn, Arnold T1 - Comparison of different failure criteria for fiber-reinforced plastics in terms of fracture curves for arbitrary stress combinations T2 - Composites Science and Technology KW - Failure Criteria KW - Fibre Reinforced Plastic Y1 - 2012 U6 - https://doi.org/10.1016/j.compscitech.2012.08.007 SN - 0266-3538 VL - 72 IS - 15 SP - 1941 EP - 1951 ER - TY - CHAP A1 - Giersch, Thomas A1 - Beirow, Bernd A1 - Popig, Frederik A1 - Kühhorn, Arnold T1 - FSI-based forced response analyses of a mistuned high pressure compressor blisk T2 - 10th International Conference on Vibrations in Rotating Machinery, 11-13 September 2012, IMechE London, UK KW - Mistuning KW - Blisk KW - Aeroelastics Y1 - 2012 SN - 978-0-85709-452-0 SN - 0-85709-452-1 N1 - Paper C1326/012 PB - Woodhead Publ. CY - Cambridge, UK ER - TY - CHAP A1 - Rauer, Georg A1 - Kühhorn, Arnold A1 - Springmann, Marcel T1 - Residual Stress Simulation of an Aero Engine Disc during Heat Treatment T2 - Proceedings of the 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012), Vienna, Austria, September 10-14, 2012 KW - Residual Stress KW - Disc Heat Treatment Y1 - 2012 SN - 978-3-9502481-9-7 PB - Techn. Univ. CY - Wien ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Nipkau, Jens T1 - Schwingungsverhalten integraler Hochdruckverdichterlaufräder unter Berücksichtigung von Fluid-Struktur-Wechselwirkung und Mistuning T2 - 61. Deutscher Luft- und Raumfahrtkongress 2012, 10. - 12. September 2012, Estrel Berlin KW - Mistuning KW - Blisk KW - Aeroelastik Y1 - 2012 UR - http://www.dglr.de/publikationen/2012/281219.pdf N1 - Beitrag DLRK2012-281219 PB - Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V. CY - Bonn ER - TY - CHAP A1 - Zuchlinski, André A1 - Kühhorn, Arnold A1 - Kober, Markus A1 - Wehrenpfennig, Lutz T1 - Kombinierte Topologie- und Parameteroptimierung des Aufhängungssystems von heckinstallierten Turbofantriebwerken T2 - 61. Deutscher Luft- und Raumfahrtkongress 2012, 10. - 12. September 2012, Estrel Berlin KW - Hecktriebwerksaufhängung KW - Optimierung Y1 - 2012 N1 - Beitrag DLRK 2012-281168 PB - Dt. Ges. für Luft- und Raumfahrt CY - Bonn ER - TY - GEN A1 - Zolochevsky, Alexander A1 - Parkhomenko, Larisa A1 - Kühhorn, Arnold T1 - Analysis of oxygen exchange-limited transport and chemical stresses in perovskite-type hollow fibers T2 - Materials Chemistry and Physics KW - Perovskite Structure Y1 - 2012 U6 - https://doi.org/10.1016/j.matchemphys.2012.05.031 SN - 0254-0584 VL - 135 IS - 2-3 SP - 594 EP - 603 ER - TY - CHAP A1 - Giersch, Thomas A1 - Hönisch, Peter A1 - Beirow, Bernd A1 - Kühhorn, Arnold T1 - Forced Response Analyses of Mistuned Radial Inflow Turbines T2 - Proceedings of the ASME Turbo Expo 2012 : presented at the 2012 ASME Turbo Expo, June 11 - 15, 2012, Copenhagen, Denmark, Vol. 7, part B KW - Blisk KW - Mistuning KW - Radial Turbine Y1 - 2012 SN - 978-0-7918-4473-1 N1 - Paper GT2012-69556 SP - 1559 EP - 1570 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Rey Villazón, José Maria A1 - Kühhorn, Arnold A1 - Weiß, Thomas T1 - A Parametric Impact Study of the Geometry, Air System and Thermal Boundary Conditions on the Life of a Two-Stage High Pressure Turbine T2 - Proceedings of the ASME Turbo Expo 2012, presented at The ASME 2012 Turbo Expo, June 11-15, 2012, Copenhagen, Denmark, Vol. 7, part A KW - High Pressure Turbine KW - Air System Y1 - 2012 SN - 978-0-7918-4473-1 N1 - Paper GT2012-68453 SP - 373 EP - 382 PB - ASME CY - New York, NY ER - TY - GEN A1 - de Silva, Tina A1 - Kühhorn, Arnold A1 - Golze, Mark T1 - Homogenization of thin structured sheet metals by using FEM T2 - Proceedings in applied mathematics and mechanics : PAMM KW - Structured Sheets KW - FEA Y1 - 2012 UR - http://onlinelibrary.wiley.com/doi/10.1002/pamm.v12.1/issuetoc U6 - https://doi.org/10.1002/pamm.201210104 N1 - GAMM 2012, 83rd Annual Scientific Conference, Darmstadt, 26. - 30. März 2012 VL - 12 IS - 1 SP - 227 EP - 228 ER - TY - GEN A1 - Zolochevsky, Alexander A1 - Martynenko, Alexander A1 - Kühhorn, Arnold T1 - Structural benchmark creep and creep damage testing for finite element analysis with material tension–compression asymmetry and symmetry T2 - Computers and Structures KW - Creep KW - Creep Damage KW - Finite Element Analysis Y1 - 2012 U6 - https://doi.org/10.1016/j.compstruc.2012.02.021 SN - 0045-7949 VL - 100-101 SP - 27 EP - 38 ER - TY - THES A1 - Kober, Markus T1 - Ein Beitrag zur strukturmechanischen Optimierung realer Bauteile in metallischer und Faserverbundbauweise unter Verwendung von wirkebenenbasierten Bruchkriterien KW - Optimierung KW - Verbundbauweise KW - Bruchkriterien Y1 - 2011 SN - 978-3-86387-085-0 PB - Mensch und Buch CY - Berlin ER - TY - GEN A1 - Giersch, Thomas A1 - Hönisch, Peter A1 - Beirow, Bernd A1 - Kühhorn, Arnold T1 - Forced Response Analyses of Mistuned Radial Inflow Turbines T2 - Journal of Turbomachinery N2 - Radial turbine wheels designed as blade integrated disks (blisk) are widely used in various industrial applications. However, related to the introduction of exhaust gas turbochargers in the field of small and medium sized engines, a sustainable demand for radial turbine wheels has come along. Despite those blisks being state of the art, a number of fundamental problems, mainly referring to fluid-structure-interaction and, therefore, to the vibration behavior, have been reported. Aiming to achieve an enhanced understanding of fluid-structure-interaction in radial turbine wheels, a numerical method, able to predict forced responses of mistuned blisks due to aerodynamic excitation, is presented. In a first step, the unsteady aerodynamic forcing is determined by modeling the spiral casing, the stator vanes, and the rotor blades of the entire turbine stage. In a second step, the aerodynamic damping induced by blade vibration is computed using a harmonic balance technique. The structure itself is represented by a reduced order model being extended by aerodynamic damping effects and aerodynamic forcings. Mistuning is introduced by adjusting the modal stiffness matrix based on results of blade by blade measurements that have been performed at rest. In order to verify the numerical method, the results are compared with strain-gauge data obtained during rig-tests. As a result, a measured low engine order excitation was found by modeling the spiral casing. Furthermore, a localization phenomenon due to frequency mistuning could be proven. The predicted amplitudes are close to the measured data. Y1 - 2013 UR - http://turbomachinery.asmedigitalcollection.asme.org/article.aspx?articleid=1672771 U6 - https://doi.org/10.1115/1.4007512 SN - 1528-8900 VL - 135 IS - 3 SP - 031034-1 EP - 031034-9 ER - TY - GEN A1 - Mahler-de Silva, Tina A1 - Kühhorn, Arnold A1 - Kober, Markus T1 - Developing a Simplified Surrogate Model for Structured Sheet Metals with Numerical and Experimental Comparisons T2 - Proceedings in applied mathematics and mechanics : PAMM N2 - It is important to steadily refine lightweight designs with regard to saving resources and energy in common with good economic efficiency. Thin structured sheet metals offer significantly improved component stiffnesses in addition to an upgraded buckling behavior compared to flat, unstructured sheet metals. By using a distortion energy based homogenization method it is possible to develop a mechanical surrogate model which describes effective mean properties. The accurate selection of symmetric and periodic boundaries enables to determine the required parameters. The conditions are contemplated on elementary cells whose structural mechanical behavior is representative for the elastic behavior of large structures. By doing this, the amount of elements can be reduced and thus the calculating time of large components can considerably be saved. For an efficient surrogate model it is required to analyze and compare numerical with experimental investigations. Some different versions of optimization will be tested to get better approximation of the data. KW - Structured Sheet Metals Y1 - 2013 UR - http://onlinelibrary.wiley.com/doi/10.1002/pamm.201310045/abstract N1 - GAMM 2013, 84th Annual Scientific Conference, Novi Sad , 18. - 22. März 2013 VL - 13 IS - 1 SP - 99 EP - 100 ER - TY - GEN A1 - Klauke, Thomas A1 - Strehlau, Ulrik A1 - Kühhorn, Arnold T1 - Integer Frequency Veering of Mistuned Blade Integrated Disks T2 - Journal of Turbomachinery N2 - As a result of more balanced blade aspect ratios of modern blade-integrated disks (blisks), interactions between disk-dominated and blade-dominated modes are becoming more and more important, especially if blade mistuning is considered. The specific vibration behavior in these transition regions is characterized by a mix of both fundamental mode types into “coupled” modes. In this paper, numerical and experimental investigations based on a front high-pressure compressor (HPC) blisk stage were carried out in order to determine the effect of blade mistuning on those regions in detail. At this, effects like mode localization and amplitude magnification are found to be weakened in an integer frequency-veering zone. Contrary to this, blisks are very sensitive to mistuning in regions of pure blade-dominated mode families with high modal density. KW - Disks KW - Blades Y1 - 2013 U6 - https://doi.org/10.1115/1.4024022 SN - 1528-8900 VL - 135 IS - 6 SP - 061004-1 EP - 061004-7 ER - TY - GEN A1 - Beirow, Bernd A1 - Giersch, Thomas A1 - Kühhorn, Arnold A1 - Nipkau, Jens T1 - Forced Response Analysis of a Mistuned Compressor Blisk T2 - Journal of Engineering for Gas Turbines and Power N2 - The forced response of an E3E-type high pressure compressor (HPC) blisk front rotor is analyzed with regard to varying mistuning and the consideration of the fluid-structure interaction (FSI). For that purpose, a reduced order model is used in which the disk remains unchanged and mechanical properties of the blades, namely stiffness and damping, are adjusted to measured as well as intentional blade frequency mistuning distributions. The aerodynamic influence coefficient technique is employed to model the aeroelastics. Depending on the blade mode, the exciting engine order, and aerodynamic influences, it is sought for the worst mistuning distributions with respect to the maximum blade displacement based on optimization analyses. Genetic algorithms using blade-alone frequencies as design variables are applied. The validity of the Whitehead limit is assessed in this context. In particular, the question is addressed if and how far aeroelastic effects, mainly caused by aerodynamic damping, combined with mistuning can even cause a reduction of the forced response compared to the ideally tuned blisk. It is shown that the strong dependence of the aerodynamic damping on the interblade phase angle is the main driver for a possible response attenuation considering the fundamental as well as a higher blade mode. Furthermore, the differences to the blisk vibration response without a consideration of the flow and an increase of the disk's stiffness are discussed. Closing, the influence of pure damping mistuning is analyzed again using optimization. KW - Blisk Otimization KW - Mistuning Y1 - 2014 U6 - https://doi.org/10.1115/1.4026537 SN - 1528-8919 VL - 136 IS - 6 ER - TY - THES A1 - Schrape, Sven T1 - Zur Simulation von Fluid-Struktur-Wechselwirkungen schwingender Verdichtergitter mittels kommerzieller Software N2 - Die vorliegende Arbeit hat zum Ziel, dem Stand der Wissenschaft und Technik entsprechende uni- und bidirektional gekoppelte Berechnungsmethoden unter Verwendung einer partitionierten Kopplung kommerzieller FE- und CFD-Programme am Lehrstuhl Strukturmechanik und Fahrzeugschwingungen der Brandenburgischen Technischen Universität Cottbus zu etablieren. Dazu erfolgt bezüglich der Kopplungsverfahren eine Überprüfung der Funktionalität am akademischen Beispiel einer querangeströmten, elastischen Platte. Vor dem Hintergrund der intensiven Forschung des Lehrstuhls auf dem Gebiet der Strukturdynamik integraler Verdichterlaufräder (Blisks) schließt sich die Validierung des eingesetzten Strömungslösers hinsichtlich einer transsonischen, instationären Verdichterströmung innerhalb schwingender Schaufelgitter an. Letztlich wird das grundlegende aeroelastische Verhalten eines realen Hochdruckverdichterlaufrades anhand eines unverstimmten, zweidimensionalen Modells analysiert. Ein Vergleich der Methoden zur Berechnung aeroelastischer Parameter ist Bestandteil der Untersuchungen. Basierend auf bidirektional gekoppelten Ergebnissen wird abschließend eine Verifizierung von abgeleiteten äquivalenten aerodynamischen Elementen innerhalb eines mechanischen, unverstimmten Ersatzmodells vorgestellt. N2 - The present work aims on establishing state of the art, partitioned, uni- and bidirectional coupling methods between commercial FE- and CFD-codes at the chair of Structural Mechanics and Vehicle Vibration Technology (Brandenburg Technical University Cottbus). Therefore a basic validation of the coupling procedures is carried out concerning an academical example of a flexible cantilever plate which is transversal flowed by an artificial fluid. Due to the intensive research of the chair onto the structural dynamic behaviour of blade integrated disks (blisks) in the past a validation of the used flow solver with respect to transsonic flows through a vibrating compressor cascade configuration is conducted. Finally the principle aeroelastic behaviour of a real high pressure compressor rotor stage is investigated by deriving a suitable two dimensional and tuned compressor cascade model. A comparison of different methods to predict aeroelastic parameter is part of the investigations. Based on results of a bidirectional coupled simulation a verification of inferred equivalent aerodynamic elements within a tuned mass-spring-damper model is figured out in conclusion. KW - Flugtriebwerk KW - Hochdruckverdichter KW - Blisk KW - Schaufelschwingung KW - Aeroelastizität Y1 - 2012 SN - 978-3-8440-1541-6 PB - Shaker CY - Aachen ER - TY - GEN A1 - Beirow, Bernd A1 - Giersch, Thomas A1 - Kühhorn, Arnold A1 - Nipkau, Jens T1 - Optimization-Aided Forced Response Analysis of a Mistuned Compressor Blisk T2 - Journal of Engineering for Gas Turbines and Power N2 - The forced response of the first rotor of an engine 3E (technology program) (E3E)-type high pressure compressor (HPC) blisk is analyzed with regard to varying mistuning, varying engine order (EO) excitations and the consideration of aero-elastic effects. For that purpose, subset of nominal system modes (SNM)-based reduced order models are used in which the disk remains unchanged while the Young's modulus of each blade is used to define experimentally adjusted as well as intentional mistuning patterns. The aerodynamic influence coefficient (AIC) technique is employed to model aero-elastic interactions. Furthermore, based on optimization analyses and depending on the exciting EO and aerodynamic influences it is searched for the worst as well as the best mistuning distributions with respect to the maximum blade displacement. Genetic algorithms using blade stiffness variations as vector of design variables and the maximum blade displacement as objective function are applied. An allowed limit of the blades' Young's modulus standard deviation is formulated as secondary condition. In particular, the question is addressed if and how far the aero-elastic impact, mainly causing aerodynamic damping, combined with mistuning can even yield a reduction of the forced response compared to the ideally tuned blisk. It is shown that the strong dependence of the aerodynamic damping on the interblade phase angle is the main driver for a possible response attenuation considering the fundamental blade mode. The results of the optimization analyses are compared to the forced response due to real, experimentally determined frequency mistuning as well as intentional mistuning. KW - Mistuning KW - Forced Response KW - Compressor Blisk Y1 - 2015 U6 - https://doi.org/10.1115/1.4028095 SN - 1528-8919 VL - 137 IS - 1 SP - 012504-1 EP - 012504-10 ER - TY - GEN A1 - Zolochevsky, Alexander A1 - Sklepus, Sergiy A1 - Galishin, Alexander A1 - Kühhorn, Arnold A1 - Kober, Markus T1 - A Comparison between the 3D and the Kirchhoff-Love Solutions for Cylinders under Creep-Damage Conditions T2 - Technische Mechanik KW - creep deformation Y1 - 2014 UR - http://www.ovgu.de/ifme/zeitschrift_tm/2014_Heft2/04_Zolochevsky_et_al.pdf VL - 34 IS - 2 SP - 104 EP - 113 ER - TY - THES A1 - Studener, Johannes T1 - Zur thermomechanischen Modellierung von Annealprozessen für große Silizium-Waferscheiben N2 - Diese Arbeit beschäftigt sich mit einem Prozeßschritt bei der Herstellung von Siliziumwafern, welche als Ausgangsprodukt für Halbleiterbauelemente dienen. Die Wafer durchlaufen bei der Herstellung unterschiedliche Prozesse, unter anderem das Annealing. Während des Anneals werden intrinsische Kristalldefekte, sog. Crystal originated Pits (COPs), bei über 1000°C thermisch aufgelöst. Der Temperaturbereich liegt dabei 200-300 °C unterhalb der Schmelztemperatur von Silizium. Demzufolge ist die Fließgrenze extrem herabgesetzt, so daß es infolge mechanischer und thermischer Belastungen zum Vergleiten (Fließen) im Kristallgitter und damit zur Qualitätsbeeinträchtigung kommen kann. Es wird erstmals aus mechanischer Sicht der komplexe Annealprozeß mit allen Einzelaspekten simulatorisch abgebildet und quantitativ erfaßbar gemacht. Dabei wird zum Einen das Ziel verfolgt, ein Lagerungskonzept zu entwickeln, welches den Ansprüchen an Reinheit, Temperaturbeständigkeit und Herstellbarkeit gerecht wird und zum Anderen den gesamten Anneal - Prozeß so zu gestalten, daß die Ausbeute von Wafern pro Zeiteinheit maximiert wird, ohne mit unerwünschten Vergleitungen rechnen zu müssen. Die vorliegende Arbeit gliedert sich in einen Grundlagenteil und einen praktischen Teil. Wesentlich für die Erfassung des Prozesses im Simulationsmodell sind verschiedene Effekte, welche zunächst theoretisch anhand einfacher analytischer und numerischer Beispiele, sowie versuchstechnisch aufgearbeitet werden sollen. Die in der Arbeit untersuchten Effekte beziehen sich auf: - die besonderen Materialeigenschaften des Silizium - Einkristalls, insbesondere dessen temperaturabhängige Fließgrenze (Upper Yield Stress) - das Lagerungskonzept, verbunden mit Kontaktproblemen zwischen Wafer und Lager (Support) - das Biegeproblem im Wafer - das Aufheizproblem bedingt durch die Wärmeübertragungsmechanismen Strahlung (zwischen Ofenwand und Wafer/Support), Leitung (innerhalb des Wafers und des Supports) und Konvektion des Gases (innerhalb des Ofens) Im praktischen Teil soll der Anneal mit Hilfe von Simulationssoftware (Finite Elemente Methode, Computational Fluid Dynamics), durch Optimierung der Lagerung und des Aufheizprozesses verbessert werden. Für die Bearbeitung dieses Kapitels werden die Untersuchungen aus dem theoretischen Teil der Arbeit als Referenz herangezogen. KW - Modellierung KW - Aneealprozesse KW - Silizium-Waferscheiben Y1 - 2006 SN - 978-3-89959-502-4 PB - Der Andere Verlag CY - Uelvesbüll ER - TY - CHAP A1 - Kober, Markus A1 - Kühhorn, Arnold A1 - Kästner, Benjamin A1 - Keskin, Akin T1 - Evaluation of the Stress and Displacement Behavior of Different LS-Dyna Element Types in Combination with Different Anti-Hourglassing Formulations and Initial Element Deformations T2 - Kurzfassungen der Vorträge, 13. LS-DYNA Forum 2014, 6. - 8. Oktober 2014, Bamberg Y1 - 2014 SN - 978-3-9816215-1-8 PB - DYNAmore GmbH CY - Stuttgart ER - TY - CHAP A1 - Kober, Markus A1 - Kühhorn, Arnold A1 - Stelldinger, Enrico A1 - Keskin, Akin T1 - Identification of Stiffness Parameters of a Simplified Aero-Engine Mount System by Using a Higher Fidelity Model of the Mount System T2 - Kurzfassungen der Vorträge, 13. LS-DYNA Forum 2014, 6. - 8. Oktober 2014, Bamberg Y1 - 2014 SN - 978-3-9816215-1-8 PB - DYNAmore GmbH CY - Stuttgart ER - TY - GEN A1 - Kober, Markus A1 - Kühhorn, Arnold A1 - Rademann, Jörg A1 - Mück, Bernhard T1 - Nonlinear topology optimization of centrifugally loaded aero-engine part with newly developed optimality-criteria based algorithm T2 - Aerospace Science and Technology N2 - In this paper a successful topology optimization of a centrifugally loaded aero-engine part is presented. For the topology optimization, which is a nonlinear problem due to several contact regions, a self-developed topology optimization algorithm in combination with a commercial FE-solver is used. The goal of the optimization was the reduction of stresses in the structure. ©2014 Rolls-Royce Deutschland Ltd & Co. KG. Published by Elsevier Masson SAS. All rights reserved. KW - Topology optimization KW - Optimality criteria KW - Aero-engine KW - Centrifugal loading Y1 - 2014 UR - http://www.sciencedirect.com/science/article/pii/S1270963814001783 U6 - https://doi.org/10.1016/j.ast.2014.09.005 VL - Vol. 39 SP - 705 EP - 711 ER - TY - GEN A1 - Stelldinger, Enrico A1 - Kühhorn, Arnold A1 - Kober, Markus T1 - Experimental evaluation of the low-velocity impact damage resistance of CFRP tubes with integrated rubber layer T2 - Composite Structures N2 - The impact performance of structural components made of fibre-reinforced plastic is often one of the limiting properties during the design process. To improve the damage resistance regarding transverse low-velocity impact loading, a rubber layer (KRAIBON®) is integrated into the composite laminate of tubular carbon/epoxy specimens. Numerous impact tests, using two different rubber compounds and three different layups, are carried out. The specimens are impacted using a modified Charpy pendulum. Force–time histories have been used to determine the damage threshold load. To visualise damage such as delaminations and inter-fibre failures, the impacted samples have been examined using microsectioning. It is shown that a significant improvement in impact damage resistance can be achieved by integrating a rubber layer into a carbon/epoxy laminate. KW - Composites KW - Tubes KW - Low-velocity impact KW - Damage resistance Y1 - 2016 U6 - https://doi.org/10.1016/j.compstruct.2015.11.069 SN - 0263-8223 IS - 139 SP - 30 EP - 35 ER - TY - GEN A1 - Kober, Markus A1 - Kühhorn, Arnold A1 - Mück, Bernhard T1 - Topologieoptimierung eines fliehkraftbelasteten Triebwerkbauteils mit einfach zu implementierendem Algorithmus unter Berücksichtigung mehrerer Zielfunktionen T2 - NAFEMS-Magazin : Zeitschrift für numerische Simulationsmethoden und angrenzende Gebiete KW - Topologieoptimierung Y1 - 2015 UR - http://www.nafems.org/publications/magazin/archive/ SN - 2311-522x IS - 35 SP - 56 EP - 66 ER - TY - CHAP A1 - Figaschewsky, Felix A1 - Giersch, Thomas A1 - Kühhorn, Arnold T1 - Forced Response Prediction of an Axial Turbine Rotor With Regard to Aerodynamically Mistuned Excitation T2 - ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, Volume 7B: Structures and Dynamics, Düsseldorf, Germany, June 16–20, 2014, Paper GT2014-25896 N2 - The design of both efficient and reliable turbomachinery blades demands a detailed knowledge of static and dynamic forces during operation. This paper aims to contribute to the proper identification of dynamic excitation mechanisms acting on an axial turbine rotor, particularly with regard to deviations of the NGV’s nominal geometry due to the use of variable vanes or tolerances in manufacturing. As variations of the NGV’s geometry disturb the perfectly periodic pattern of the downstream flow features, other spectral components than those correlated with the number of stator vanes are possible to appear. These frequency components may lead to low engine order excitation of fundamental blade modes at high engine speeds. Under these operating conditions the rotor is already highly loaded with centrifugal forces and additional dynamic excitation may cause unacceptable stresses. Thus aerodynamic mistuning might be a limiting criterion for the design of a highly loaded turbine rotor. Within this paper 2 dimensional CFD-models are used to investigate both, the determination of the wake of a geometric mistuned stator guide vane and the influence of the resulting excitation on the adjacent rotor stage due to aerodynamically mistuned flow. In order to generate a mistuned NGV geometry, variations of pitch and stagger angle are taken into account and a mesh morpher is used to produce computational domains of the mistuned geometry on the basis of a nominal mesh. Additionally a simplified reconstruction process based on a set of CFD computations will be introduced, being able to reproduce the spectral components of the mistuned wake by specifying a certain geometric mistuning distribution. The prediction of the resulting modal forces is carried out in time domain and approaches with lower fidelity are investigated with respect to their capability of reproducing the key features of an aerodynamically mistuned excitation mechanism. KW - Rotors KW - Turbines Y1 - 2014 SN - 978-0-7918-4577-6 U6 - https://doi.org/10.1115/GT2014-25896 PB - ASME ER - TY - CHAP A1 - Rauer, Georg A1 - Kühhorn, Arnold A1 - Springmann, Marcel T1 - Residual Stress Modelling and Inverse Heat Transfer Coefficients Estimation of a Nickel-Based Superalloy Disc Forging T2 - ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, Volume 6, Düsseldorf, Germany, June 16–20, 2014, Paper GT2014-25827 N2 - Aero engine disc forgings are subjected to heat treatment operations, i.e., solution treatment followed by quenching and artificial aging, with the aim of achieving improved mechanical material properties. During heat treatment high inhomogeneous temperature gradients and long loading times at elevated temperatures occur and lead to the development and partial relaxation of bulk residual stresses. The intention of this paper is to describe the residual stress modelling of a nickel-based ATI 718Plus® superalloy disc forging. For this purpose, an uncoupled thermomechanical finite element problem is solved consisting of a thermal model based on transient, spatially varying heat transfer coefficients (HTCs) and a stress model incorporating the nonlinear material behaviour to account for thermal induced inelastic deformations. A graphical user interface based application has been created for the automatic estimation of the a priori unknown HTCs by using a serial solution procedure for the two dimensional inverse heat conduction problem (IHCP) based on the function specification method. The estimated temperature fields have been compared at the thermocouple positions with the corresponding measurement data and confirm the suitability of the inverse algorithm to this problem. A rate-independent elasto-plastic constitutive model is used to simulate the residual stress formation while quenching the disc forging. Two creep models have been adjusted to uniaxial tensile test data and applied to simulate the stress relaxation during aging. Finally, this paper presents the numerical results of the stress analysis. Copyright © 2014 by Rolls-Royce Deutschland Ltd & Co KG KW - Nickel KW - Superalloys KW - Forging KW - Stress KW - Modeling Y1 - 2014 SN - 978-0-7918-4575-2 U6 - https://doi.org/10.1115/GT2014-25827 PB - ASME ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Giersch, Thomas A1 - Nipkau, Jens T1 - Optimization-Aided Forced Response Analysis of a Mistuned Compressor Blisk T2 - ASME Turbo Expo 2014, Turbine Technical Conference and Exposition, Volume 7B: Structures and Dynamics, Düsseldorf, Germany, June 16–20, 2014, Paper GT2014-25915 N2 - The forced response of the first rotor of an E3E-type high pressure compressor blisk is analyzed with regard to varying mistuning, varying engine order excitations and the consideration of aeroelastic effects. For that purpose, SNM-based reduced order models are used in which the disk remains unchanged while the Young’s modulus of each blade is used to define experimentally adjusted as well as intentional mistuning patterns. The aerodynamic influence coefficient technique is employed to model aeroelastic interactions. Furthermore, based on optimization analyses and depending on the exciting EO and aerodynamic influences it is searched for the worst as well as the best mistuning distributions with respect to the maximum blade displacement. Genetic algorithms using blade stiffness variations as vector of design variables and the maximum blade displacement as objective function are applied. An allowed limit of the blades’ Young’s modulus standard deviation is formulated as secondary condition. In particular, the question is addressed if and how far the aeroelastic impact, mainly causing aerodynamic damping, combined with mistuning can even yield a reduction of the forced response compared to the ideally tuned blisk. It is shown that the strong dependence of the aerodynamic damping on the inter-blade phase angle is the main driver for a possible response attenuation considering the fundamental blade mode. The results of the optimization analyses are compared to the forced response due to real, experimentally determined frequency mistuning as well as intentional mistuning. Copyright © 2014 by Rolls-Royce Deutschland Ltd & Co KG Y1 - 2014 SN - 978-0-7918-4577-6 U6 - https://doi.org/10.1115/GT2014-25915 PB - ASME ER - TY - CHAP A1 - Giersch, Thomas A1 - Figaschewsky, Felix A1 - Hönisch, Peter A1 - Kühhorn, Arnold A1 - Schrape, Sven T1 - Numerical Analysis and Validation of the Rotor Blade Vibration Response Induced by High Pressure Compressor Deep Surge T2 - ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, Volume 7B: Structures and Dynamics Düsseldorf, Germany, June 16–20, 2014, Paper GT2014-26295 N2 - The following paper presents a numerical analysis of a deep surge cycle of a 4.5 stage research compressor. The resulting unsteady loads are used to determine the response of two particular rotor blade rows that are then compared to strain gauge data from measurements. Within a deep surge cycle the compressor experiences a rapid change of the flow field from forward to reversed flow. This rapid breakdown is linked to a new mean blade load. Hence, the rapid change in blade loads are able to excite fundamental blade modes similar to an impulse load. The resulting vibration magnitudes might reach critical levels. This paper demonstrates two different approaches to evaluate the unsteady flow during a surge cycle. The first uses a three dimensional, time accurate finite volume solver for viscid compressible flows to calculate the transient surge cycle of the compressor. The compressor itself is represented by a multi-blade-row sector model. The second approach makes use of the same solver and compressor domain to determine steady state characteristics of the HPC in forward, stalled and reversed flow. Based on these characteristics an one dimensional finite volume solver for inviscid compressible flows was developed to determine the transient compressor behavior. The one dimensional solver represents the compressor by source terms that are linked to the previously determined steady state characteristics. Copyright © 2014 by Rolls-Royce Deutschland Ltd & Co KG KW - Compressors KW - High pressure (Physics) KW - Numerical analysis Y1 - 2014 SN - 978-0-7918-4577-6 U6 - https://doi.org/10.1115/GT2014-26295 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Rey Villazón, José Maria A1 - Wildow, Toni A1 - Kühhorn, Arnold A1 - Benton, Robert A1 - Göhler, Moritz T1 - Impact of the Secondary Air System Design Parameters on the Calculation of Turbine Discs Windage T2 - ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, Volume 5C: Heat Transfer, Düsseldorf, Germany, June 16–20, 2014, Paper GT2014-26050 N2 - The rotating components in gas turbines are very highly stressed as a result of the centrifugal and thermal loads. One of the main functions of the secondary air system (SAS) is to ensure that the rotating components are surrounded by air that optimizes disc lifing and integrity. The SAS is also responsible for the blade cooling flow supply, preventing hot gas ingestion from the main annulus into the rotor-stator cavities, and for balancing the net axial load in the thrust bearings. Thus, the SAS design requires a multidisciplinary compromise to provide the above functions, while minimizing the penalty of the secondary flows on engine performance. The phenomenon known as rotor-stator drag or windage is defined as the power of the rotor moment acting on its environment. The power loss due to windage has a direct impact on the performance of the turbine and the overall efficiency of the engine. This paper describes a novel preliminary design approach to calculate the windage of the rotor-stator cavities in the front of a typical aero engine HP turbine. The new method is applied to investigate the impact of the SAS design parameters on the windage losses and on the properties of the cooling flows leading to the main annulus. Initially, a theoretical approach is followed to calculate the power losses of each part of the HPT front air feed system. Then, a 1D-network integral model of the cavities and flow passages of the HPT front is built and enhanced with detailed flow field correlations. The new 1D-flow network model offers higher fidelity regarding local effects. A result comparison between the theoretical calculation and the prediction of the enhanced flow network model puts forward the relevance of the local flow field effects in the design concept of the SAS. Using the enhanced 1D-flow network models, the SAS design parameters are varied to assess their influence on the windage and pumping power calculation. As a conclusion, the paper shows how the SAS design can have a significant influence on the HPT overall power and the air that is fed back into the turbine blade rows. Controlling these features is essential to bid a competitive technology in the aero engine industry. Copyright © 2014 by Rolls-Royce Deutschland Ltd & Co KG KW - Design KW - Turbines KW - Disks Y1 - 2014 SN - 978-0-7918-4573-8 U6 - https://doi.org/10.1115/GT2014-26050 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Beirow, Bernd A1 - Maywald, Thomas A1 - Kühhorn, Arnold T1 - Mistuning and Damping Analysis of a Radial Turbine Blisk in Varying Ambient Conditions T2 - ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, Volume 7B: Structures and Dynamics Düsseldorf, Germany, June 16–20, 2014, Paper GT2014-25521 N2 - A mistuned radial turbine impeller is analyzed with respect to the impact of varying ambient pressures and temperatures as well on frequency response functions and modal damping ratios. Beginning at room conditions, a finite element model of an impeller wheel at rest is updated based on experimentally determined mistuning in terms of blade dominated frequencies. The following numerical forced response analyses yield a maximum blade displacement amplification of 67% compared to the tuned reference. In addition, modal damping ratios are determined in dependence on the ambient pressure ranging from technical vacuum at 1 mbar up to 6000 mbar in a pressure chamber. Shaker excitation and laser Doppler vibrometry response measurement is employed in this context. A linear dependence of modal damping ratios on ambient pressure and a dominating damping contribution of the surrounding air even for higher modes could be proved. Moreover, the experimental determination of frequency response functions (FRF) at technical vacuum yields a better separation of resonance peaks compared to room conditions at 1013 mbar and hence, this data allows for more accurate model-updates in principle. It is proved that numerical models updated regarding mistuning at room conditions are well suited to predict the forced response at arbitrary pressures if measured modal damping ratios at these pressures are considered. Finally, within analyzing the effect of increasing structural temperatures with the surrounding air at 1013 mbar included slightly decreasing resonance frequencies but strongly increasing FRF-amplitudes are determined. Copyright © 2014 by ASME KW - Damping KW - Turbines Y1 - 2014 SN - 978-0-7918-4577-6 U6 - https://doi.org/10.1115/GT2014-25521 PB - ASME ER - TY - CHAP A1 - Behnam, Nouri A1 - Kühhorn, Arnold T1 - Automated CAE process for thermo-mechanical lifing prediction of a parameterized turbine blade with internal cooling T2 - Joined 11th World Congress on Computational Mechanics (WCCM XI), 5th European Conference on Computational Mechanics (ECCM V), 6th European Conference on Computational Fluid Dynamics (ECFD VI) conference Y1 - 2014 UR - http://www.wccm-eccm-ecfd2014.org/admin/files/fileabstract/a2070.pdf ER - TY - CHAP A1 - Rey Villazón, José Maria A1 - Kühhorn, Arnold T1 - Adaptive CFD-Enhanced Windage Modelling for Aero Engine Turbine Rotor-Stator Cavities T2 - Joined 11th World Congress on Computational Mechanics (WCCM XI), 5th European Conference on Computational Mechanics (ECCM V), 6th European Conference on Computational Fluid Dynamics (ECFD VI) conference Y1 - 2014 UR - http://www.wccm-eccm-ecfd2014.org/admin/files/fileabstract/a1666.pdf ER - TY - CHAP A1 - Behnam, Nouri A1 - Kühhorn, Arnold T1 - Interdisciplinary Analysis of a Turbine Blade With Internal Cooling Including Local Distribution and Rotation Effects T2 - 11th AIAA/ASME Joint Thermophysics and Heat Transfer Conference, Atlanta, GA KW - gas turbine engines KW - cooling Y1 - 2014 UR - http://arc.aiaa.org/doi/abs/10.2514/6.2014-2388 SN - 978-1-62410-281-3 PB - AIAA CY - Reston, VA ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Golze, Mark A1 - Klauke, Thomas T1 - Experimentelle Untersuchungen des strukturdynamischen Verhaltens von Hochdruckverdichterschaufeln in Integralbauweise (Blisks) mittels Laser-Doppler-Vibrometrie KW - Blisks KW - Integralbauweise Y1 - 2004 ER - TY - CHAP A1 - Rey Villazón, José Maria A1 - Berthold, Martin A1 - Kühhorn, Arnold T1 - Adaptive Flow Field Thermal Modeling Techniques for Turbine Rotor-Stator Cavities T2 - Proceedings of ASME Turbo Expo 2013, San Antonio, Texas, USA , June 3-7, 2013, Vol. 3C: Heat Transfer, Paper GT2013-94845 Y1 - 2013 UR - http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=1776262 SN - 978-0-7918-5516-4 U6 - https://doi.org/10.1115/GT2013-94845 PB - ASME CY - New York ER - TY - THES A1 - Klauke, Thomas T1 - Schaufelschwingungen integraler, realer Verdichterräder im Hinblick auf Verstimmung und Lokalisierung KW - Schaufelschwingung KW - Verdichter KW - Flattern Y1 - 2007 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:co1-opus-4081 ER - TY - CHAP A1 - Springmann, Marcel A1 - Scherzer, M. A1 - Kuna, M. A1 - Kühhorn, Arnold T1 - Numerical simulation of localization phenomena in the frame of damage parameter identification T2 - Seminar: Materials modeling, FE simulations of the behavior of modern industrial materials including failure, 5th - 6th December 2006, Niedernhausen (Wiesbaden), Germany Y1 - 2006 SN - 1-874376-19-0 PB - NAFEMS Contact Nordic Countries CY - Grafing b. München ER - TY - CHAP A1 - Keskin, Akin A1 - Kober, Markus A1 - Stelldinger, Enrico A1 - Kühhorn, Arnold A1 - Böhm, Holger A1 - Hornig, Andreas A1 - Hufenbach, Werner T1 - On the quantification of errors of a pre-processing effort reducing contact meshing approach : AIAA 2015-0408 T2 - 53rd AIAA Aerospace Sciences Meeting 2015, Kissimmee, Florida, USA, 5 - 9 January 2015, held at the AIAA SciTech Forum 2015, vol. 4 Y1 - 2015 SN - 978-1-5108-0117-2 U6 - https://doi.org/10.2514/6.2015-0408 SP - 3113 EP - 3124 PB - Curran CY - Red Hook, NY ER - TY - CHAP A1 - Rey Villazón, José Maria A1 - Wildow, Toni A1 - Kühhorn, Arnold A1 - Benton, Robert A1 - Eydam, Tobias T1 - Advanced Turbine Preliminary Design Environment for the automatic Generation of Secondary Air System Models T2 - ASME Turbo Expo 2015: Turbine Technical Conference and Exposition Volume 7A: Structures and Dynamics Montreal, Quebec, Canada, June 15–19, 2015 N2 - The design and development process of an aero engine is a complex and time-consuming task that involves many disciplines and company departments with different objectives and requirements. Along the preliminary design phase, multiple concepts are assessed in order to select a competitive technology. The engine design process, which was traditionally subdivided into modular component tasks, is nowadays considered as a multi-disciplinary workflow. Having recognized the need for developing advanced turbine preliminary design tools, this work focuses on enhancing the integration of turbine design disciplines, improving the accuracy of models and speeding the time to generate models. The proposed process facilitates an automated turbine Secondary Air System (SAS) and turbine discs concept definition. Furthermore, the process of CAD models and flow network models generation is accelerated via automation of the engineering workflow. This is accomplished through a novel Java based data model, where the design of turbine discs and SAS features is captured in a programmable framework. In the application section, the preliminary design definition of a reference HP turbine subsystem is replicated using the newly developed common design environment. The automated workflow is then used to generate the corresponding CAD models, recognize the subsystem flow network, and generate the 1D flow network model. The results are then compared to the experimentally validated model of a reference engine. As conclusion, the automated workflow offers a quick and parametric model generation process, while providing a good level of fidelity for the preliminary design phase. Copyright © 2015 by Rolls-Royce Deutschland Ltd & Co KG KW - Design KW - Turbines Y1 - 2015 SN - 978-0-7918-5676-5 U6 - https://doi.org/10.1115/GT2015-42661 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Wagner, Frank A1 - Kühhorn, Arnold T1 - Response surface based robust design optimization on the example of a high pressure turbine blade T2 - 8. Dresdner Probabilistik-Workshop, Technische Universität Dresden, 08.-09. Okt. 2015 N2 - Nowadays in a product design process the manufacturing tolerances have to be considered. Therefore a deterministic optimization needs to be converted into a robust design optimization. Usually the reference geometry is represented by a parametric model and an appropriate set of default parameters. In the robust design approach this set is replaced by a set of distributed parameters. These distributions are known from a previous design or needs to be estimated. This work is about a robust design and multi objective optimization of a high pressure turbine blade (first row) from an actual aero engine. The multidisciplinary objectives are the combined life of the aero-foil (LCF and creep) for the outer and inner geometry, the efficiency and the mass of the blade. For the input set different kinds of parameter will be examined. Apart from the major geometry parameters, which represent the external surface of the blade, parameters for material and boundary conditions will be investigated as well. The used workflow contains the Rolls-Royce tool parablading for the creation of the external aero-foil, Siemens NX for general geometry manipulation, Hydra as Navier-Stokes solver and SC03 for the structural problem and is set up in the automation software ISight. Focus of this work is the creation of response surfaces and physical integrity of the delivered results. Therefore, different validation criteria will be consulted. These are implemented in a Matlab toolbox and tested on typical optimization test problems. Based on the validated response surfaces a huge number of evaluations is possible, which is necessary for a robust design optimization. As the major result a set of Pareto optimal designs will be delivered. Y1 - 2015 UR - http://www.probabilistik.de/abstract/abstract_15_wagner.html UR - http://www.probabilistik.de/prog_15.html CY - Dresden ER - TY - CHAP A1 - Giersch, Thomas A1 - Kühhorn, Arnold A1 - Figaschewsky, Felix T1 - Probabilistic Analysis of Low Engine Order Excitation Due to Geometric Perturbations of Upstream Nozzle Guide Vanes : ISABE-2015-20165 T2 - Conference Proceedings from the 22nd International Symposium on Air Breathing Engines, October 25-30, 2015, Phoenix, Arizona Y1 - 2015 UR - http://hdl.handle.net/2374.UC/745749 SP - 1 EP - 9 PB - ISABE ER - TY - CHAP A1 - Maywald, Thomas A1 - Beirow, Bernd A1 - Heinrich, Christoph Rocky A1 - Kühhorn, Arnold T1 - Vacuum Spin Test Series of a Turbine Impeller with Focus on Mistuning and Damping by Comparing Tip Timing and Strain Gauge Results T2 - ASME Turbo Expo 2015: Turbine Technical Conference and Exposition Volume 7B: Structures and Dynamics Montreal, Quebec, Canada, June 15–19, 2015 N2 - This paper describes preparation, execution and evaluation of a comprehensive bladed disk spin test series. At the example of an turbine impeller the effects of rotation and temperature are analyzed with special focus on mistuning and damping. The forced response is measured synchronously via 13 identical positioned strain gauges on each blade as well as via blade tip-timing. Subsequently it is possible to compare the results of both systems. During the test series rotational speed varies in the range from 10.000 up to 19.000 RPM. Simultaneously, the wheel is heated up to 820 K by an oven. A number of pre-selected natural frequencies, damping ratios and operating deflection shapes are evaluated and compared with respect to different rotational speeds and impeller temperatures. Copyright © 2015 by ASME KW - Rotation KW - Vacuum KW - Impellers KW - Damping KW - Turbines KW - Strain gages Y1 - 2015 SN - 978-0-7918-5677-2 U6 - https://doi.org/10.1115/GT2015-42649 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Wagner, Frank A1 - Kühhorn, Arnold A1 - Parchem, Roland T1 - Robust design optimization applied to a high pressure turbine blade based on surrogate modelling techniques T2 - ASME Turbo Expo 2015: Turbine Technical Conference and Exposition Volume 7A: Structures and Dynamics Montreal, Quebec, Canada, June 15–19, 2015 N2 - To achieve reverse objectives in engine design, advanced modelling and analysis methods are among the key research technologies. In the presented work, a robust design optimization of a first stage high pressure turbine blade has been carried out. This blade derives from a current production of a Rolls-Royce aero engine. The motivation of this work is to show that the methodology of robust design optimization can be applied to high pressure turbine blades. A fully automated workflow, which encapsulated the integral blade design and analysis process, has been used. The main workflow objective is a representative life value of the external surface of the blade. In addition, the workflow enables the engineering uses to consider sub objectives like mass, efficiency and life at critical locations of the blade. These can also be taken into account in the multi-objective robust design optimization. This research also focuses on the use of surrogate models, with attention to the delivery of a physically correct result. For this purpose, the validation of the applied methods has a huge significance and a toolbox was created to generate and evaluate the quality of the surrogate models. In the present case sixteen geometry parameters were considered. In order to show that this methodology is not limited to geometry variation, parameters for material specification and for boundary conditions were varied in addition. The surrogate model was trained by the workflow generated DoE-data and could be used for different kinds of optimization. As a conclusion, it has been demonstrated that the methodology can be used for the engineering design process of turbine blades, while delivering physically correct results. The different techniques for surrogate modelling were examined and compared. With the help of these surrogate models, an optimization of life, mass and efficiency with 22.5 million evaluations was possible. Finally, an overview of the methodology for the case of a real world turbine blade could be given, and an improved blade in the sense of multi-objective robust design was found. Copyright © 2015 by Rolls-Royce Deutschland Ltd & Co KG KW - Turbine blades KW - High pressure (Physics) KW - Design KW - Modeling KW - Optimization Y1 - 2015 SN - 978-0-7918-5676-5 U6 - https://doi.org/10.1115/GT2015-42365 ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Figaschewsky, Felix A1 - Nipkau, Jens T1 - Effect of Mistuning and Damping on the Forced Response of a Compressor Blisk Rotor T2 - ASME Turbo Expo 2015: Turbine Technical Conference and Exposition Volume 7A: Structures and Dynamics Montreal, Quebec, Canada, June 15–19, 2015 N2 - The forced response of an E3E-type high pressure compressor blisk front rotor is analyzed with regard to intentional mistuning and its robustness towards additional random mistuning. Both a chosen alternating mistuning pattern and artificial mistuning patterns optimized concerning the forced response are considered. Focusing on three different blade modes, subset of nominal system mode-based reduced order models are employed to compute the forced response. The disk remains unchanged while the Young’s modulus of each blade is used to define the particular mistuning pattern. The well established aerodynamic influence coefficient technique is employed to model aeroelastic coupling and hence to consider the strongly mode- and inter blade phase angle-dependent aerodynamic damping contribution. It has been found that a reduction of the maximum forced response beyond that of the tuned reference can be achieved for particular mistuning patterns and all modes considered. This implies an exciting engine order which would cause a low nodal diameter mode in case of a tuned blisk. At best a nearly 50% reduction of maximum response magnitudes is computed for the fundamental bending mode and large mistuning. The solution proved to be robust towards additional random mistuning of reasonable magnitude, which is of particular interest with regard to a potential technical realization. In case of small mistuning as assumed for the first torsion and the longitudinal bending mode the advantage of achieving response magnitudes beyond the tuned reference gets lost indeed, if random mistuning is superimposed. However, mostly a lower response level is calculated compared to responses obtained from models adjusted to mistuning determined by experiment. Copyright © 2015 by ASME KW - Compressors KW - Damping KW - Rotors Y1 - 2015 SN - 978-0-7918-5677-2 U6 - https://doi.org/10.1115/GT2015-42036 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Figaschewsky, Felix A1 - Kühhorn, Arnold T1 - Analysis of Mistuned Blade Vibrations Based on Normally Distributed Blade Individual Natural Frequencies T2 - ASME Turbo Expo 2015: Turbine Technical Conference and Exposition Volume 7B: Structures and Dynamics Montreal, Quebec, Canada, June 15–19, 2015 N2 - With increasing demands for reliability of modern turbomachinery blades the quantification of uncertainty and its impact on the designed product has become an important part of the development process. This paper aims to contribute to an improved approximation of expected vibration amplitudes of a mistuned rotor assembly under certain assumptions on the probability distribution of the blade’s natural frequencies. A previously widely used lumped mass model is employed to represent the vibrational behavior of a cyclic symmetric structure. Aerodynamic coupling of the blades is considered based on the concept of influence coefficients leading to individual damping of the traveling wave modes. The natural frequencies of individual rotor blades are assumed to be normal distributed and the required variance could be estimated due to experiences with the applied manufacturing process. Under these conditions it is possible to derive the probability distribution of the off-diagonal terms in the mistuned equations of motions, that are responsible for the coupling of different circumferential modes. Knowing these distributions recent limits on the maximum attainable mistuned vibration amplitude are improved. The improvement is achieved due to the fact, that the maximum amplification depends on the mistuning strength. This improved limit can be used in the development process, as it could partly replace probabilistic studies with surrogate models of reduced order. The obtained results are verified with numerical simulations of the underlying structural model with random mistuning patterns based on a normal distribution of individual blade frequencies. Copyright © 2015 by ASME KW - Vibration KW - Blades Y1 - 2015 SN - 978-0-7918-5677-2 U6 - https://doi.org/10.1115/GT2015-43121 PB - ASME CY - New York, NY ER - TY - THES A1 - Beirow, Bernd T1 - Experimentelle und theoretische Untersuchungen des dynamischen Verhaltens von Fernmeldetürmen Y1 - 2000 PB - BTU, Lehrstuhl Statik und Dynamik CY - Cottbus ER - TY - CHAP A1 - Nouri, Behnam A1 - Lehmann, Knut A1 - Kühhorn, Arnold T1 - Investigations on Nusselt Number Enhancement in Ribbed Rectangular Turbine Blade Cooling Channels of Different Aspect Ratios and Rotation Numbers T2 - ASME Turbo Expo 2013: Turbine Technical Conference and Exposition, San Antonio, Texas, USA, June 3–7, 2013, Vol. 3A, Heat Transfer, Paper GT2013-94710 N2 - In the drive for higher cycle efficiencies in gas turbine engines, turbine blades are seeing an increasingly high heat load. This in turn demands improvements in the internal cooling system and a better understanding of both the level and distribution of the internal heat-transfer. A typical approach to enhance the internal cooling of the turbine blade is by casting angled ‘low blockage’ ribs on the walls of the cooling channels. The objective of the present paper is to determine the detailed Nusselt number distribution in rectangular internal channels with ribs. This knowledge can be used to guide the overall design e.g. to achieve high levels of heat-transfer where required. The effects of rotation as well as the interaction effects of the position and direction of ribs on opposite walls of the cooling channel have been investigated. Numerical calculations have been carried out using the commercial CFD code Fluent to investigate the local Nusselt number enhancement factor in rectangular ducts of different aspect ratios (0.5, 1 and 2) which have 45° or 90° angled ribs located on two opposite walls. This has been studied for different Rotation number Ro (0–0.45) and with a Reynolds number >30000. The first series of studies has been carried out with the same experimental setup as by Han [1]. The geometry was slightly changed to avoid the effect of high heat transfer at the entry. This study identifies important vortical structures, which are dependent on the direction and the position of the ribs. This has a profound effect on the distribution of heat-transfer within the passage. It is shown that the two smooth walls of the duct have different average Nusselt number ratio Nu/NuFD enhancement depending on the rib angle. In addition, based on numerical investigations, simple correlations have been developed for the rotational influence of the internal Nusselt number distribution. A major finding is that the effect of rotation is dominant for low aspect ratio channels and the local enhancement due to the rib position and angle is more dominant for high aspect ratio channels. Y1 - 2013 UR - http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=1776088 SN - 978-0-7918-5514-0 U6 - https://doi.org/10.1115/GT2013-94710 PB - ASME CY - New York ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Giersch, Thomas A1 - Nipkau, Jens T1 - Forced Response Analysis of a Mistuned Compressor Blisk T2 - ASME Turbo Expo 2013: Turbine Technical Conference and Exposition, San Antonio, Texas, USA, June 3–7, 2013, Vol. 7B, Structures and Dynamics, Paper GT2013-94142 N2 - The forced response of an E3E-type HPC-blisk front rotor is analyzed with regard to varying mistuning and the consideration of the fluid-structure interaction (FSI). For that purpose, a reduced order model is used in which the disk remains unchanged and mechanical properties of the blades namely stiffness and damping are adjusted to measured as well as intentional blade frequency mistuning distributions. The aerodynamic influence coefficient technique is employed to model the aeroelastics. Depending on the blade mode, the exciting engine order and aerodynamic influences it is sought for the worst mistuning distributions with respect to the maximum blade displacement based on optimization analyses. Genetic algorithms using blade alone frequencies as design variables are applied. The validity of the Whitehead-limit is assessed in this context. In particular, the question is addressed if and how far aeroelastic effects, mainly caused by aerodynamic damping, combined with mistuning can even cause a reduction of the forced response compared to the ideally tuned blisk. It is shown that the strong dependence of the aerodynamic damping on the inter-blade phase angle is the main driver for a possible response attenuation considering the fundamental as well as a higher blade mode. Furthermore, the differences to the blisk vibration response without a consideration of the flow and an increase of the disk’s stiffness are discussed. Closing, the influence of pure damping mistuning is analyzed again using optimization. KW - Compressors KW - Blades KW - Blisks KW - Mistuning Y1 - 2013 UR - http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=1776795 SN - 978-0-7918-5527-0 U6 - https://doi.org/10.1115/GT2013-94142 PB - ASME CY - New York ER - TY - JOUR A1 - Kühhorn, Arnold A1 - Beirow, Bernd A1 - Golze, Mark A1 - Studener, Johannes T1 - Strukturmechanische Analyse einer Triebwerksverdichter-Schaufelscheibe N2 - Die Verbesserung von Kalibriermethoden für Hochdruckverdichterstufen in ausgeführter Integralbauweise verlangt von den Ingenieuren ein detaillierteres Verständnis der strukturdynamischen Zusammenhänge dieses komplexen Bauteils. Als Ausgangsbasis werden zunächst für das perfekte Normdesign bei Ausnutzung der vorliegenden zyklischen Rotationssymmetrie numerische Ergebnisse vorgestellt. Dabei stehen bezüglich des Schwingverhaltens die Kopplungseffekte zwischen Scheibe und Schaufeln im Mittelpunkt, wobei experimentelle Untersu-chungen am realen Bauteil ergänzend hinzugezogen werden. Zukünftig wird in einem weiteren Schritt im Rahmen erheblich aufwendigerer Berechnungen mit der Berücksichtigung von Imperfektionen hinsichtlich der filigranen Schaufeln die Rotationssymmetrie aufgegeben und somit die Basis für eine gezielte Beeinflussung des Schwingverhaltens infolge von Mistuning - Effekten geschaffen. KW - FEM-Simulation KW - Experimentelle Modalanalysen KW - Kopplungseffekte Y1 - 2002 ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Golze, Mark A1 - Parchem, Roland A1 - Johann, E. T1 - Experimentelle und numerische Untersuchungen hinsichtlich einer Festigkeitsauslegungsoptimierung von Hochdruck-Verdichter-Schaufelscheiben unter besonderer Berücksichtigung von Mistuningeffekten T2 - Deutscher Luft- und Raumfahrtkongress 2003, München, 17. bis 20. November 2003, Bd. 2 KW - Festigkeitsauslegungsoptimierung KW - Hochdruck-Verdichter-Schaufelscheiben KW - Mistuningeffekte Y1 - 2003 SP - 1495 EP - 1504 PB - DGLR CY - Bonn ER - TY - CHAP A1 - Klauke, Thomas A1 - Kühhorn, Arnold A1 - Golze, Mark A1 - Villwock, J. A1 - Lenk, Olaf T1 - Finite-Elemente-Anwendung neuerer Faserverbund-Bruchkriterien und deren Verifizierung mittels CFK-Bauteilprüfung T2 - Deutscher Luft- und Raumfahrtkongress 2003, München, 17. bis 20. November 2003, Bd. 1 KW - FEM KW - Faserverbund KW - CFK-Bauteilprüfung Y1 - 2003 SP - 113 EP - 120 PB - Dt. Ges. für Luft- und Raumfahrt CY - Bonn ER - TY - CHAP A1 - Studener, Johannes A1 - Kühhorn, Arnold T1 - FE-Simulation des thermischen Aufheizvorganges eines Silizium-Wafers im RTA (Rapid Thermal Anneal) - Prozess T2 - Tagungsband, 15. Deutschsprachige ABAQUS-Benutzerkonferenz, 22. - 23. September 2003, Fulda KW - Silizium-Wafer KW - RTA-Prozess KW - Simulation Y1 - 2003 PB - ABAQUS Deutschland GmbH CY - Aachen [u.a.] ER - TY - CHAP A1 - Kober, Markus A1 - Kühhorn, Arnold A1 - Stelldinger, Enrico A1 - Keskin, Akin T1 - Considerations About the Necessary Mesh Density of Bearings in Detailed Finite Element Models T2 - ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, Volume 7B: Structures and Dynamics Düsseldorf, Germany, June 16–20, 2014, Paper GT2014-25624 N2 - In order to predict properly the behavior of very complex mechanical models, much focus needs to be done on the level of model details as well as the techniques used to predict component movements based on mechanical and thermal loads. In particular bearings and joints play a significant role in big model assemblies such as aero-engines where most of the structures are modeled by solid elements rather than using traditional shell or beam elements. This approach is very complex and expensive in terms of computational effort however can lead to increased simulation accuracy when done properly. This publication will answer questions related to the modeling techniques required for detailed bearings (not only rotor bearings) and joints of an aero-engine application where these components are not idealized or simplified, i.e. the ball in a ball joint is meshed by solid elements. The investigation will discuss the question about the number of elements needed to mesh a ball joint in such a way that a correct rotation is possible. If the mesh is too coarse, a rotation would be impossible due to the faceting of the rotating parts. It will be shown that a proper rotation depends on a correct relation between the radius of the inner ball, the gap size of the bearing and the number of nodes in the circumferential direction. For this relation an analytical formula has been derived and successfully tested at some examples. Furthermore, some finite element codes offer the possibility of smoothed contact surfaces. These options improve the situation but they might cause issues too. For this reason these smoothed contact options are also considered under the aspects mentioned above. Copyright © 2014 by Rolls-Royce Deutschland Ltd & Co KG KW - Density KW - Bearings Y1 - 2014 SN - 978-0-7918-4577-6 U6 - https://doi.org/10.1115/GT2014-25624 PB - ASME ER - TY - GEN A1 - Klauke, Thomas A1 - Kühhorn, Arnold A1 - Beirow, Bernd A1 - Golze, Mark T1 - Numerical Investigations of Localized Vibrations of Mistuned Blade Integrated Disks (Blisks) Y1 - 2009 ER - TY - CHAP A1 - Stelldinger, Enrico A1 - Kühhorn, Arnold A1 - Kober, Markus T1 - Otimization of a Carbon-fiber-reinforced Plastic Composite Structure using the Example of a Wing Rigger KW - Optimization KW - Composite KW - Wing Rigger Y1 - 2011 ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Nipkau, Jens T1 - An Equivalent Blisk Model Considering the Influence of the Air Flow on Blade Vibrations of a Mistuned Compressor Blisk T2 - Vibration Problems ICOVP 2011, The 10th International Conference on Vibration Problems, The 10th International Conference on Vibration Problems KW - Mistuned Compressor Blisk KW - Blade Vibrations KW - Air Flow Y1 - 2011 SN - 978-94-007-2068-8 SP - 549 EP - 555 PB - Springer CY - Berlin [u.a.] ER - TY - CHAP A1 - Nipkau, Jens A1 - Kühhorn, Arnold A1 - Beirow, Bernd T1 - Modal and Aeroelastic Analysis of a Mistuned Compressor Blisk Using an Equivalent Blisk Model KW - Blisk vibration KW - Mistuning KW - Aerodynamic Influence Coefficients Y1 - 2011 ER - TY - CHAP A1 - Beirow, Bernd A1 - Nipkau, Jens A1 - Kühhorn, Arnold T1 - Modal and Aeroelastic Analysis of a Compressor Blisk Considering Mistuning T2 - Proceedings of the ASME Turbo Expo 2011, presented at the ASME 2011 Turbo Expo, June 6 - 10, 2011, Vancouver, British Columbia, Canada, Vol. 6, part B KW - Mistuning KW - Compressor Blisk Y1 - 2011 SN - 978-0-7918-5466-2 N1 - GT2011-45849 SP - 1309 EP - 1319 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Höhnisch, Peter A1 - Kühhorn, Arnold A1 - Beirow, Bernd T1 - Experimental and Numerical Analysis of Radial Turbine Bliks with Regard to Mistuning KW - Tadial KW - Turbine KW - Vibration KW - Mistuning KW - Model Update Y1 - 2011 ER - TY - THES A1 - Beirow, Bernd T1 - Grundlegende Untersuchungen zum Schwingungsverhalten von Verdichterlaufrädern in Integralbauweise Y1 - 2009 SN - 978-3-8322-8729-0 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Kühhorn, Arnold A1 - Beirow, Bernd A1 - Strehlau, Ulrik T1 - Zum Schwingungsverhalten integraler Hochdruckverdichterlaufräder Y1 - 2009 ER - TY - JOUR A1 - Grosch, A. A1 - Beirow, Bernd T1 - Ausgewählte bauphysikalische Probleme von Wohngebäuden in Stahl-Leichtbauweise Y1 - 2001 ER - TY - CHAP A1 - Springmann, Marcel A1 - Kühhorn, Arnold A1 - Rauer, Georg A1 - Giersch, Thomas T1 - Constitutive Modelling of Plastic and Creep Behavior of the Nickel Base Superalloy ALLVAC® 718PLUS® under Heat Treatment Conditions KW - Behavior KW - Nickel-Based Superalloy KW - Heat Treatment Conditions Y1 - 2011 ER - TY - CHAP A1 - Maywald, Thomas T1 - Grundlegende Charakterisierung des Eigenschwingverhaltens eines zyklisch symmetrischen Mehrmassenschwingers mittels analytischer Methoden T2 - Deutscher Luft- und Raumfahrtkongress, Tagungsband Bremen 2011, Manuskripte KW - Eigenschwingverhalten KW - Mistuning KW - zyklisch symmetrischer Mehrmassenschwinger Y1 - 2011 SP - 809 EP - 816 PB - DGLR CY - Bonn ER -