TY - CHAP A1 - Korsch, Helge A1 - Dafnis, Athanasios A1 - Reimerdes, Hans-Günther A1 - Braun, Carsten A1 - Ballmann, Josef T1 - Dynamic qualification of the HIRENASD elastic wing model T2 - Motto: Luft- und Raumfahrt: Lehre, Forschung, Industrie - gemeinsam innovativ. Deutscher Luft- und Raumfahrtkongress 2006 : Braunschweig, 06. bis 09. November 2006. Jahrbuch / Deutsche Gesellschaft für Luft- und Raumfahrt. 2006 Y1 - 2006 SP - 1441 EP - 1450 PB - Dt. Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth (DGLR) CY - Bonn 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 - 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 - 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 - RPRT A1 - Reimer, Lars A1 - Wellmer, Georg A1 - Braun, Carsten A1 - Ballmann, Josef T1 - Aerodynamische Simulation und Optimierung in der Flugzeugentwicklung. Teilvorhabenbezeichnung: Aerodynamische Optimierung unter Berücksichtigung von Struktureigenschaften auf der Basis reduzierter Strukturmodelle, Verbundvorhaben MEGADESIGN. Schlussbericht. Berichtszeitraum: 01.06.2003-31.05.2007. BMBF-Forschungsbericht Y1 - 2007 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 - JOUR A1 - Jordan, Sabine D. A1 - Krüger, Markus A1 - Willmes, Diana M. A1 - Redemann, Nora A1 - Wunderlich, F. Thomas A1 - Brönneke, Hella S. A1 - Merkwirth, Carsten A1 - Kashkar, Hamid A1 - Olkkonen, Vesa M. A1 - Böttger, Thomas A1 - Braun, Thomas A1 - Seibler, Jost A1 - Brüning, Jens C. T1 - Obesity-induced overexpression of miRNA-143 inhibits insulin-stimulated AKT activation and impairs glucose metabolism JF - Nature Cell Biology N2 - The contribution of altered post-transcriptional gene silencing to the development of insulin resistance and type 2 diabetes mellitus so far remains elusive. Here, we demonstrate that expression of microRNA (miR)-143 and 145 is upregulated in the liver of genetic and dietary mouse models of obesity. Induced transgenic overexpression of miR-143, but not miR-145, impairs insulin-stimulated AKT activation and glucose homeostasis. Conversely, mice deficient for the miR-143–145 cluster are protected from the development of obesity-associated insulin resistance. Quantitative-mass-spectrometry-based analysis of hepatic protein expression in miR-143-overexpressing mice revealed miR-143-dependent downregulation of oxysterol-binding-protein-related protein (ORP) 8. Reduced ORP8 expression in cultured liver cells impairs the ability of insulin to induce AKT activation, revealing an ORP8-dependent mechanism of AKT regulation. Our experiments provide direct evidence that dysregulated post-transcriptional gene silencing contributes to the development of obesity-induced insulin resistance, and characterize the miR-143–ORP8 pathway as a potential target for the treatment of obesity-associated diabetes. Y1 - 2011 U6 - http://dx.doi.org/10.1038/ncb2211 SN - 1465-7392 VL - 13 IS - 4 SP - 434 EP - 446 PB - Nature CY - New York ER - TY - JOUR A1 - Neu, Eugen A1 - Janser, Frank A1 - Khatibi, Akbar A. A1 - Braun, Carsten A1 - Orifici, Adrian C. T1 - Operational Modal Analysis of a wing excited by transonic flow JF - Aerospace Science and Technology N2 - Operational Modal Analysis (OMA) is a promising candidate for flutter testing and Structural Health Monitoring (SHM) of aircraft wings that are passively excited by wind loads. However, no studies have been published where OMA is tested in transonic flows, which is the dominant condition for large civil aircraft and is characterized by complex and unique aerodynamic phenomena. We use data from the HIRENASD large-scale wind tunnel experiment to automatically extract modal parameters from an ambiently excited wing operated in the transonic regime using two OMA methods: Stochastic Subspace Identification (SSI) and Frequency Domain Decomposition (FDD). The system response is evaluated based on accelerometer measurements. The excitation is investigated from surface pressure measurements. The forcing function is shown to be non-white, non-stationary and contaminated by narrow-banded transonic disturbances. All these properties violate fundamental OMA assumptions about the forcing function. Despite this, all physical modes in the investigated frequency range were successfully identified, and in addition transonic pressure waves were identified as physical modes as well. The SSI method showed superior identification capabilities for the investigated case. The investigation shows that complex transonic flows can interfere with OMA. This can make existing approaches for modal tracking unsuitable for their application to aircraft wings operated in the transonic flight regime. Approaches to separate the true physical modes from the transonic disturbances are discussed. Y1 - 2016 U6 - http://dx.doi.org/10.1016/j.ast.2015.11.032 SN - 1270-9638 VL - 49 SP - 73 EP - 79 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Schildt, P. A1 - Braun, Carsten A1 - Marcocca, P. T1 - Flight testing the extra 330LE flying testbed T2 - 48th Annual International Symposium of the Society of Flight Test Engineers 2017 Y1 - 2017 SN - 978-151085387-4 N1 - 48th Annual International Symposium of the Society of Flight Test Engineers 2017, SFTE 2017; Destin; United States; 30 October 2017 through 2 November 2017 SP - 349 EP - 362 ER - TY - CHAP A1 - Ludowicy, Jonas A1 - Rings, René A1 - Finger, Felix A1 - Braun, Carsten T1 - Sizing Studies of Light Aircraft with Serial Hybrid Propulsion Systems T2 - Luft- und Raumfahrt - Digitalisierung und Vernetzung : Deutscher Luft- und Raumfahrtkongress 2018. 4. - 6. September 2018 - Friedrichshafen Y1 - 2018 ER - TY - CHAP A1 - Finger, Felix A1 - Götten, Falk A1 - Braun, Carsten T1 - Initial Sizing for a Family of Hybrid-Electric VTOL General Aviation Aircraft T2 - 67. Deutscher Luft- und Raumfahrtkongress 2018 Y1 - 2018 ER - TY - CHAP A1 - Ludowicy, Jonas A1 - Rings, René A1 - Finger, Felix A1 - Braun, Carsten T1 - Sizing Studies of Light Aircraft with Parallel Hybrid Propulsion Systems T2 - Deutscher Luft- und Raumfahrtkongress 2018 Y1 - 2018 U6 - http://dx.doi.org/10.25967/480227 ER - TY - JOUR A1 - Götten, Falk A1 - Finger, Felix A1 - Havermann, Marc A1 - Braun, Carsten A1 - Gomez, Francisco A1 - Bill, C. T1 - On the flight performance impact of landing gear drag reduction methods for unmanned air vehicles JF - Deutscher Luft- und Raumfahrtkongress 2018 N2 - The flight performance impact of three different landing gear configurations on a small, fixed-wing UAV is analyzed with a combination of RANS CFD calculations and an incremental flight performance algorithm. A standard fixed landing gear configuration is taken as a baseline, while the influence of retracting the landing gear or applying streamlined fairings is investigated. A retraction leads to a significant parasite drag reduction, while also fairings promise large savings. The increase in lift-to-drag ratio is reduced at high lift coefficients due to the influence of induced drag. All configurations are tested on three different design missions with an incremental flight performance algorithm. A trade-off study is performed using the retracted or faired landing gear's weight increase as a variable. The analysis reveals only small mission performance gains as the aerodynamic improvements are negated by weight penalties. A new workflow for decision-making is presented that allows to estimate if a change in landing gear configuration is beneficial for a small UAV. Y1 - 2018 U6 - http://dx.doi.org/10.25967/480058 PB - DGLR CY - Bonn ER - TY - CHAP A1 - Finger, Felix A1 - Braun, Carsten A1 - Bil, Cees T1 - Case studies in initial sizing for hybrid-electric general aviation aircraft T2 - 2018 AIAA/IEEE Electric Aircraft Technologies Symposium, Cincinnati, Ohio Y1 - 2018 U6 - http://dx.doi.org/10.2514/6.2018-5005 ER - TY - JOUR A1 - Finger, Felix A1 - Braun, Carsten A1 - Bil, Cees T1 - Impact of electric propulsion technology and mission requirements on the performance of VTOL UAVs JF - CEAS Aeronautical Journal N2 - One of the engineering challenges in aviation is the design of transitioning vertical take-off and landing (VTOL) aircraft. Thrust-borne flight implies a higher mass fraction of the propulsion system, as well as much increased energy consumption in the take-off and landing phases. This mass increase is typically higher for aircraft with a separate lift propulsion system than for aircraft that use the cruise propulsion system to support a dedicated lift system. However, for a cost–benefit trade study, it is necessary to quantify the impact the VTOL requirement and propulsion configuration has on aircraft mass and size. For this reason, sizing studies are conducted. This paper explores the impact of considering a supplemental electric propulsion system for achieving hovering flight. Key variables in this study, apart from the lift system configuration, are the rotor disk loading and hover flight time, as well as the electrical systems technology level for both batteries and motors. Payload and endurance are typically used as the measures of merit for unmanned aircraft that carry electro-optical sensors, and therefore the analysis focuses on these particular parameters. Y1 - 2018 U6 - http://dx.doi.org/10.1007/s13272-018-0352-x SN - 1869-5582 print SN - 1869-5590 online VL - 10 IS - 3 SP - 843 PB - Springer ER - TY - CHAP A1 - Finger, Felix A1 - Braun, Carsten A1 - Bil, Cees T1 - The Impact of Electric Propulsion on the Performance of VTOL UAVs T2 - Deutscher Luft- und Raumfahrtkongress 2017, DLRK , München Y1 - 2017 ER - TY - CHAP A1 - Finger, Felix A1 - Braun, Carsten A1 - Bil, Cees T1 - A Review of Configuration Design for Distributed Propulsion Transitioning VTOL Aircraft T2 - Asia-Pacific International Symposium on Aerospace Technology 2017, APISAT 2017, Seoul, Korea Y1 - 2017 ER - TY - CHAP A1 - Finger, Felix A1 - Braun, Carsten A1 - Bil, Cees T1 - An Initial Sizing Methodology for Hybrid-Electric Light Aircraft T2 - AIAA AVIATION Forum 2018 Aviation Technology, Integration, and Operations Conference, Atlanta, Georgia, June 25 - 29, 2018 Y1 - 2018 U6 - http://dx.doi.org/10.2514/6.2018-4229 ER -