TY - JOUR A1 - Kühhorn, Arnold A1 - Beirow, Bernd T1 - Schwingungsreduzierung an der Antriebseinheit eines Ultraleichtflugzeuges JF - Forum der Forschung N2 - Auf Grund der im Rahmen eines Testfluges subjektiv durch den Piloten festgestellten hohen Schwingungsamplituden wird das dynamische Verhalten eines Ultraleichtflugzeugmotors inklusive der Motoraufhängung untersucht. Hierin wir der numerische Teil der Untersuchun-gen durch eine finite Elemente Simulation abgedeckt, in deren Rahmen die wesentlichen Ei-genschwingformen der Antriebseinheit samt Motorträger identifiziert wurden. Ergänzend mit den Ergebnissen einer experimentellen Modalanalyse und Betriebsschwingungsmessungen konnten wesentliche Informationen gewonnen werden, aus denen als Maßnahme zur Schwin-gungsreduzierung die Erhöhung der Schwungradmasse abgeleitet wurde. KW - Experimentelle Modalanalyse KW - FEM-Simulation KW - Ultraleichtflugzeug Y1 - 2002 SN - 0947-6989 VL - 6 SP - 105 EP - 108 ET - 14 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 - Chmielewski, Tadeusz A1 - Gorski, Piotr A1 - Beirow, Bernd A1 - Kretzschmar, Joachim T1 - Comparison of Theoretical and Experimental Free Vibrations of High Industrial Chimney Interacting with Soil T2 - Teoria konstrukcji, konstrukcje metalowe, konstrukcje betonowe, XLVIII Konferencja Naukowa Komitetu Inżynierii Lądowej i Wodnej PAN i Komitetu Nauki PZITB Krynica 2002, Opole-Krynica 15-20 września 2002 r. N2 - Theoretical frequencies and mode shapes of the high multi-flue industrial chimney, which is located in the power station of Opole, interacting with soil have been evaluated through the application of the finite element method. The aim of the present paper is to study the free vibrations of this chimney applying dynamic testing in full scale to confirm a calculation model and to obtain important information on the effect of soil interacting with the chimney. KW - Free vibration analysis KW - towers KW - Influence of soil KW - vibration measurement Y1 - 2002 SN - 83-7125-091-6 SP - 27 EP - 34 PB - Dolnośląskie Wydaw. Edukacyjne CY - Wrocław ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold T1 - Schwingungsreduzierung an der Antriebseinheit eines Ultraleichtflugzeuges : Beitrag Deutscher Luft- und Raumfahrtkongress Stuttgart 2002 N2 - Initiiert durch die im Rahmen eines Testfluges subjektiv durch den Piloten festgestellten hohen Schwingungsamplituden wird das dynamische Verhalten eines Ultraleichtflugzeugmotors inklusive der Motoraufhängung untersucht. Hierin wir der numerische Teil der Untersuchungen durch eine finite Elemente Simulation abgedeckt, in deren Rahmen die wesentlichen Eigenschwingformen der Antriebseinheit samt Motorträger identifiziert wurden. Ergänzend mit den Ergebnissen einer experimentellen Modalanalyse und Betriebsschwingungsmessungen konnten wesentliche Informationen gewonnen werden, aus denen als Maßnahme zur Schwin-gungsreduzierung die Erhöhung der Schwungradmasse abgeleitet wurde. KW - Experimentelle Modalanalyse KW - FEM-Simulation KW - Order-track-Analysen Ultraleichflugzeug Y1 - 2002 ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Osterrieder, Peter T1 - Windinduzierte Schwingungserregung von Fernmeldetürmen T2 - Fluid-Struktur-Wechselwirkung, Tagung Wiesloch, 11. und 12. Juni 2002 N2 - Vorstellung eines stochastischen Verfahrens zur Berechnung windinduzierter Querschwingungen, Präsentation am Beispiel des Fernmeldeturmes Cottbus KW - stochastische Querschwingungsberechnung KW - Lock-in-Effekt Y1 - 2002 SN - 3-18-091682-6 SP - 407 EP - 422 PB - VDI-Verlag CY - Düsseldorf ER - TY - JOUR A1 - Grosch, A. A1 - Beirow, Bernd T1 - Ausgewählte bauphysikalische Probleme von Wohngebäuden in Stahl-Leichtbauweise Y1 - 2001 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 - JOUR A1 - Kühhorn, Arnold A1 - Beirow, Bernd A1 - Studener, Johannes T1 - Messtechnische Beanspruchungsuntersuchungen beim Transport von Glasröhrenkollektoren KW - Beanspruchungsuntersuchungen KW - Glasröhrenkollektoren Y1 - 2003 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 - 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 - Golze, Mark T1 - Experimental and Numerical Investigations of High pressure Compressor Blades Vibration Behavior Considering Mistuning KW - vibration Y1 - 2005 ER - TY - CHAP A1 - Klauke, Thomas A1 - Beirow, Bernd A1 - Kühhorn, Arnold T1 - Experimental and numerical investigations of blade mistuning and strain gauge application effects in aero engine development Y1 - 2005 ER - TY - GEN A1 - Chmielewski, Tadeusz A1 - Gorski, Piotr A1 - Beirow, Bernd A1 - Kretzschmar, Joachim T1 - Theoretical and experimental free vibrations of tall industrial chimney with flexibility of soil T2 - Engineering structures Y1 - 2005 SN - 0141-0296 VL - 27 IS - 1 SP - 25 EP - 34 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 - JOUR A1 - Kühhorn, Arnold A1 - Beirow, Bernd A1 - Klauke, Thomas A1 - Golze, Mark T1 - Simulation der Mistuningeffekte von Hochdruckverdichter-Schaufelscheiben zur Bestimmung kritischer Schwingungen in Flugtriebwerken KW - Mistuningeffekte KW - Blisks Y1 - 2004 ER - TY - CHAP A1 - Beirow, Bernd A1 - Osterrieder, Peter A1 - Kühhorn, Arnold ED - Dinkler, Dieter T1 - Stochastisches Konzept für die Berechnung von Stahlschornsteinen infolge wirbelerregter Querschwingungen T2 - Berichte der Fachtagung Baustatik - Baupraxis 8, am 21. und 22. März 2002 in Braunschweig Y1 - 2002 SN - 3-926031-95-6 SP - 271 EP - 280 PB - TU, Institut für Statik CY - Braunschweig 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 - Kretzschmar, Joachim A1 - Beirow, Bernd T1 - Dynamic Diagnostic of Timber Structures Supported by Neural Networks Y1 - 2000 ER - TY - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Golze, Mark A1 - Klauke, Thomas T1 - Strukturdynamische Untersuchungen an Hochdruckverdichterschaufelscheiben unter Berücksichtigung von Mistuningeffekten T2 - Modalanalyse und Identifikation, Verfahren und Anwendungen bei dynamischen Systemen, Tagung Wiesloch, 25. und 26. Mai 2004 KW - Verdichterschaufelscheiben KW - Mistuningeffekte Y1 - 2004 SN - 3-18-091825-X SP - 351 EP - 372 PB - VDI-Verlag CY - Düsseldorf ER - TY - CHAP A1 - Klauke, Thomas A1 - Kühhorn, Arnold A1 - Beirow, Bernd T1 - Numerische Untersuchung des Schwingverhaltens von Hochdruckverdichter-Blisks mit fertigungsbedingten Anweichungen KW - Blisks KW - Schwingverhalten Y1 - 2004 ER - TY - JOUR A1 - Osterrieder, Peter A1 - Beirow, Bernd T1 - Advanced dynamic methods for structural evaluation of TV towers, Proseedings of the Centre of Structural Integrity Y1 - 2003 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 A1 - Beirow, Bernd A1 - Parchem, Roland A1 - Klauke, Thomas T1 - Schaufelschwingungen bei realen Verdichter-Integralrädern (BLISK) T2 - Deutscher Luft- und Raumfahrtkongress 2006, Braunschweig, 06. bis 09. November 2006, Bd. 2 KW - Schaufelschwingungen KW - Blisk Y1 - 2006 SP - 1199 EP - 1208 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 - JOUR A1 - Beirow, Bernd T1 - Secure Power for Jet Engines KW - Jet Engines Y1 - 2006 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 - Strehlau, Ulrik A1 - Kühhorn, Arnold A1 - Beirow, Bernd T1 - Numerische und experimentelle Untersuchungen realer Hochdruckverdichterschaufelscheiben in Integralbauweise Y1 - 2009 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 - 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 - 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 - 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 - Kühhorn, Arnold A1 - Beirow, Bernd A1 - Strehlau, Ulrik T1 - Zum Schwingungsverhalten integraler Hochdruckverdichterlaufräder Y1 - 2009 ER - 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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 -