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 - 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 - 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 - CHAP A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Figaschewsky, Felix A1 - Hönisch, Peter A1 - Giersch, Thomas A1 - Schrape, Sven T1 - Model Update and Validation of a Mistuned High Pressure Compressor Blisk T2 - Proceedings of ISABE 2017, ISABE-2017-22568, Manchester, September 3.-8., 2017 Y1 - 2017 UR - https://isabe2017.org/ PB - ISABE 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 - Popig, Frederik A1 - Hönisch, Peter A1 - Kühhorn, Arnold T1 - Experimental and Numerical Analysis of Geometrical Induced Mistuning T2 - ASME Turbo Expo 2015: Turbine Technical Conference and Exposition Volume 7B: Structures and Dynamics Montreal, Quebec, Canada, June 15–19, 2015 N2 - The application of high pressure compressor (HPC) rotors manufactured as blisk (Blade Integrated Disk) is ever-expanding in modern jet engine designs. Despite the major advantages of less mass and higher efficiency, the most challenging problem is lower mechanical damping due to the loss of damping between blades root’s and the disk. Mistuning is induced by material inhomogeneities, manufacturing tolerances or wear during use and leads to amplitude magnification and mode localization. From the experimental point of view mistuning can be evaluated via experimental vibration analysis in terms of frequency deviations. Furthermore optical measurements can be evaluated in terms of geometrical deviations between the real and designed geometry. From the structural point of view a mistuned blisk model can be obtained by morphing the nodes of the geometrical tuned FE model or by performing blade individual stiffness mistuning due to modification of Young’s modulus. The following work is focused on the numerical prediction of mistuned blisk vibrations. Therefore, the research blisk of the 4 stage research compressor, manufactured as job-production, is analyzed. For this research blisk optical measurement data as well as experimentally obtained frequency patterns are available. In a first part mistuning identification in terms of experimental vibration analysis and Proper Orthogonal Decomposition of the geometrical deviations is presented. In a second part mistuning modeling in terms of stiffness mistuning and geometrical mistuning is applied to the tuned FE-model and the numerical results are evaluated against experimental data regarding accuracy. Furthermore, the impact of geometrical deviations on mistuning is analyzed. Copyright © 2015 by Rolls-Royce Deutschland Ltd & Co KG KW - Numerical analysis KW - Blades KW - Finite element model KW - Disks KW - Stiffness KW - Damping Y1 - 2015 UR - http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleID=2428632 SN - 978-0-7918-5677-2 U6 - https://doi.org/10.1115/GT2015-43272 PB - ASME CY - New York, NY ER - TY - THES A1 - Hönisch, Peter T1 - Strukturbeschreibung und Parameteridentifikation realer Radialturbinenlaufräder N2 - Die vorliegende Arbeit beschäftigt sich mit den Auswirkungen fertigungsbedingter Abweichungen auf das strukturdynamische Verhalten realer Radialturbinenlaufräder. Am Anfang steht die mathematische Beschreibung zyklisch rotationssymmetrischer Laufräder. Verstimmung (engl. Mistuning) führt jedoch zu einer Störung der zyklischen Rotationssymmetrie. Die Auswirkungen werden anhand von experimentellen Untersuchungen an 6 Radialturbinenlaufrädern gleichen Typs analysiert. Die Ergebnisse dienen im weiteren Verlauf als Eingangsparameter für den Prozess der Parameteridentifikation. Aufbauend auf einer Analyse verschiedener Modellierungsvarianten wird das Subset of Nominal System Modes, ein sogenanntes systemmodenbasiertes Modell reduzierter Ordnung für die numerischen Untersuchungen ausgewählt. In Verbindung mit einer sektorindividuellen Beschreibung der Steifigkeit, ist dieses für die mathematische Beschreibung des dynamischen Verhaltens realer Radialturbinenlaufräder geeignet. Erweiterte probabilistische Studien zur Bestimmung der maximalen Beanspruchungsüberhöhung infolge von Mistuning führen zum Konzept der Modalen Dichte. Dieses praxistaugliche Konzept erlaubt die Einordnung der einzelnen Schwingungsformen bezüglich ihrer Neigung zur Ausprägung starker Beanspruchungsüberhöhungen. Hierfür ist einzig die Eigenwertanalyse des idealen Laufrades erforderlich. Im zweiten Teil der Arbeit wird die Übertragbarkeit der im Stillstand gewonnenen Parameter zur Modellbeschreibung realer Radialturbinenlaufräder auf die Betriebsbedingungen untersucht. Dabei erfolgt die Separierung der Einflussgrößen Drehzahl, Temperatur und Umströmung in einem vakuumtauglichen Prüfstand. Um eine möglichst vollständige experimentelle Datenbasis zu erhalten, wird die Blade Tip Timing Methode zur Erfassung der Schaufelschwingungsamplitude verwendet. Hiermit kann die Schwingungsantwort jeder Schaufel erfasst werden. Beim Vergleich der numerische Vorhersage mit den experimentellen Daten ergeben sich gute Übereinstimmungen, sofern die Effekte transienter Resonanzdurchgänge berücksichtigt werden. KW - Turbine KW - Schwingung KW - Mistuning KW - Blade Tip Timing KW - radial KW - transient Y1 - 2019 SN - 978-3-86387-989-1 PB - Mensch und Buch Verlag CY - Berlin ER - TY - CHAP A1 - Hönisch, Peter A1 - Kühhorn, Arnold T1 - Mistuning und Dämpfung von Radialturbinen KW - Mistuning KW - Dämpfung KW - Radialturbine Y1 - 2011 ER - TY - GEN A1 - Beirow, Bernd A1 - Kühhorn, Arnold A1 - Figaschewsky, Felix A1 - Hönisch, Peter A1 - Giersch, Thomas A1 - Schrape, Sven T1 - Model update and validation of a mistuned high-pressure compressor blisk T2 - The Aeronautical Journal N2 - In order to prepare an advanced 4-stage high-pressure compressor rig test campaign, details regarding both accomplishment and analysis of preliminary experiments are provided in this paper. The superior objective of the research project is to contribute to a reliable but simultaneously less conservative design of future high pressure blade integrated disks (blisk). It is planned to achieve trend-setting advances based on a close combination of both numerical and experimental analyses. The analyses are focused on the second rotor of this research compressor, which is the only one being manufactured as blisk. The comprehensive test program is addressing both surge and forced response analyses e.g. caused by low engine order excitation. Among others the interaction of aeroelastics and blade mistuning is demanding attention in this regard. That is why structural models are needed, allowing for an accurate forced response prediction close to reality. Furthermore, these models are required to support the assessment of blade tip timing (BTT) data gathered in the rig tests and strain gauge (s/g) data as well. To gain the maximum information regarding the correlation between BTT data, s/g-data and pressure gauge data, every blade of the second stage rotor (28 blades) is applied with s/g. However, it is well known that s/g on blades can contribute additional mistuning that had to be considered upon updating structural models. Due to the relevance of mistuning, efforts are made for its accurate experimental determination. Blade-by-blade impact tests according to a patented approach are used for this purpose. From the research point of view, it is most interesting to determine both the effect s/g-instrumentation and assembling the compressor stages on blade frequency mistuning. That is why experimental mistuning tests carried out immediately after manufacturing the blisk are repeated twice, namely, after s/g instrumentation and after assembling. To complete the pre-test program, the pure mechanical damping and modal damping ratios dependent on the ambient pressure are experimentally determined inside a pressure vessel. Subsequently the mistuning data gained before is used for updating subset of nominal system mode (SNM) models. Aerodynamic influence coefficients (AICs) are implemented to take aeroelastic interaction into account for forced response analyses. Within a comparison of different models, it is shown for the fundamental flap mode (1F) that the s/g instrumentation significantly affects the forced response, whereas the impact of assembling the compressor plays a minor role. KW - Blisk KW - Mistuning KW - Aerodynamic damping Y1 - 2019 U6 - https://doi.org/10.1017/aer.2018.149 SN - 2059-6464 SN - 0001-9240 VL - 123 IS - 1260 SP - 230 EP - 247 ER -