TY - CHAP A1 - Ballmann, Josef A1 - Boucke, Alexander A1 - Braun, Carsten T1 - Aeroelastic sensitivity in the transonic regime T2 - Symposium Transsonicum IV : proceedings of the IUTAM symposium held in Göttingen, Germany, 2 - 6 September 2002 / ed. by Helmut Sobieczky. Fluid mechanics and its applications. Vol. 73 Y1 - 2003 SN - 978-94-010-3998-7 SP - 225 EP - 236 PB - Kluwer Academic CY - Dordrecht ER - TY - CHAP A1 - Ballmann, Josef A1 - Dafnis, Athanasios A1 - Braun, Carsten A1 - Korsch, Helge A1 - Reimerdes, Hans-Günther A1 - Braun, Carsten A1 - Ballmann, Josef T1 - The HIRENASD project: High Reynolds number aerostructural dynamics experiments in the European Transonic Wind Tunnel (ETW) T2 - ICAS 2006 proceedings : 25th Congress of the International Council of the Aeronautical Sciences ; Hamburg, Germany, 3 - 8 September, 2006 : 25th International Congress of Aeronautical Sciences Y1 - 2006 SN - 0-9533991-7-6 SP - Paper No. 2006-5.11.2 PB - Optimage CY - Edinburgh ER - TY - JOUR A1 - Bergmann, Ole A1 - Möhren, Felix A1 - Braun, Carsten A1 - Janser, Frank T1 - On the influence of elasticity on swept propeller noise JF - AIAA SCITECH 2023 Forum N2 - High aerodynamic efficiency requires propellers with high aspect ratios, while propeller sweep potentially reduces noise. Propeller sweep and high aspect ratios increase elasticity and coupling of structural mechanics and aerodynamics, affecting the propeller performance and noise. Therefore, this paper analyzes the influence of elasticity on forward-swept, backward-swept, and unswept propellers in hover conditions. A reduced-order blade element momentum approach is coupled with a one-dimensional Timoshenko beam theory and Farassat's formulation 1A. The results of the aeroelastic simulation are used as input for the aeroacoustic calculation. The analysis shows that elasticity influences noise radiation because thickness and loading noise respond differently to deformations. In the case of the backward-swept propeller, the location of the maximum sound pressure level shifts forward by 0.5 °, while in the case of the forward-swept propeller, it shifts backward by 0.5 °. Therefore, aeroacoustic optimization requires the consideration of propeller deformation. Y1 - 2023 U6 - http://dx.doi.org/10.2514/6.2023-0210 N1 - Session: Propeller, Open Rotor, and Rotorcraft Noise II AIAA SCITECH 2023 Forum, 23-27 January 2023, National Harbor, MD & Online PB - AIAA ER - TY - CHAP A1 - Braun, Carsten T1 - Ein modulares Verfahren für die numerische aeroelastische Analyse von Luftfahrzeugen T2 - Motto: Wissen und Visionen für ein nachhaltiges Wachstum : Deutscher Luft- und Raumfahrtkongress 2008, Darmstadt, 23. bis 25. September 2008 / Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V. (DGLR). DGLR-Jahrbuch. 2008 Y1 - 2008 SP - 787 EP - 796 PB - DGLR CY - Bonn ER - TY - BOOK A1 - Braun, Carsten T1 - Ein modulares Verfahren für die numerische aeroelastische Analyse von Luftfahrzeugen N2 - Aachen, Techn. Hochschule, Diss., 2007 Y1 - 2007 ER - TY - CHAP A1 - Braun, Carsten A1 - Boucke, Alexander A1 - Ballmann, Josef T1 - Numerical prediction of the wing deformation of a high speed transport aircraft type wind tunnel model by direct aeroelastic simulation T2 - Conference proceedings : CEAS/AIAA/DGLR International Forum on Aeroelasticity and Structural Dynamics IFASD 2005 : München, June 28 - July 1, 2005. DGLR-Bericht. 2005,04 Y1 - 2005 SN - 3-932182-43-X PB - DGLR CY - Bonn ER - TY - CHAP A1 - Braun, Carsten A1 - Boucke, Alexander A1 - Ballmann, Josef T1 - Numerical study of the influence of dynamic pressure and deflected ailerons on the deformation of a high speed wing model T2 - High performance computing in science and engineering '04. Transactions of the High Performance Computing Center Stuttgart (HLRS) 2004 / Eds.: Egon Krause ... Y1 - 2005 SN - 3-540-22943-4 SP - 225 EP - 236 PB - Springer CY - Berlin ER - TY - CHAP A1 - Braun, Carsten A1 - Boucke, Alexander A1 - Hanke, M. A1 - Karavas, Alexandros A1 - Ballmann, Josef T1 - Prediction of the model deformation of a high speed transport aircraft type wing by direct aeroelastic simulation T2 - High performance computing in science and engineering '03. Transactions of the High Performance Computing Center Stuttgart (HLRS) 2003 / Eds.: Egon Krause ... Y1 - 2003 SN - 978-3-540-40850-5 SP - 331 EP - 342 PB - Springer CY - Berlin ER - TY - CHAP A1 - Britten, G. A1 - Braun, Carsten A1 - Hesse, M. A1 - Ballmann, Josef T1 - Computational aeroelasticity with reduced structural models T2 - Flow modulation and fluid-structure interaction at airplane wings : research results of the Collaborative Research Center SFB 401 at RWTH Aachen, University of Technology, Aachen, Germany / Josef Ballmann (Ed.) Notes on numerical fluid mechanics and multidisciplinary design. Vol. 84 Y1 - 2003 SN - 3-540-40209-8 SP - 275 EP - 299 PB - Springer CY - Berlin ER - TY - JOUR A1 - Böhnisch, Nils A1 - Braun, Carsten A1 - Muscarello, Vincenzo A1 - Marzocca, Pier T1 - About the wing and whirl flutter of a slender wing–propeller system JF - Journal of Aircraft N2 - Next-generation aircraft designs often incorporate multiple large propellers attached along the wingspan (distributed electric propulsion), leading to highly flexible dynamic systems that can exhibit aeroelastic instabilities. This paper introduces a validated methodology to investigate the aeroelastic instabilities of wing–propeller systems and to understand the dynamic mechanism leading to wing and whirl flutter and transition from one to the other. Factors such as nacelle positions along the wing span and chord and its propulsion system mounting stiffness are considered. Additionally, preliminary design guidelines are proposed for flutter-free wing–propeller systems applicable to novel aircraft designs. The study demonstrates how the critical speed of the wing–propeller systems is influenced by the mounting stiffness and propeller position. Weak mounting stiffnesses result in whirl flutter, while hard mounting stiffnesses lead to wing flutter. For the latter, the position of the propeller along the wing span may change the wing mode shapes and thus the flutter mechanism. Propeller positions closer to the wing tip enhance stability, but pusher configurations are more critical due to the mass distribution behind the elastic axis. Y1 - 2024 U6 - http://dx.doi.org/10.2514/1.C037542 SN - 1533-3868 SP - 1 EP - 14 PB - American Institute of Aeronautics and Astronautics ER -