@inproceedings{KorschDafnisReimerdesetal.2006, author = {Korsch, Helge and Dafnis, Athanasios and Reimerdes, Hans-G{\"u}nther and Braun, Carsten and Ballmann, Josef}, title = {Dynamic qualification of the HIRENASD elastic wing model}, series = {Motto: Luft- und Raumfahrt: Lehre, Forschung, Industrie - gemeinsam innovativ. Deutscher Luft- und Raumfahrtkongress 2006 : Braunschweig, 06. bis 09. November 2006. Jahrbuch / Deutsche Gesellschaft f{\"u}r Luft- und Raumfahrt. 2006}, booktitle = {Motto: Luft- und Raumfahrt: Lehre, Forschung, Industrie - gemeinsam innovativ. Deutscher Luft- und Raumfahrtkongress 2006 : Braunschweig, 06. bis 09. November 2006. Jahrbuch / Deutsche Gesellschaft f{\"u}r Luft- und Raumfahrt. 2006}, publisher = {Dt. Gesellschaft f{\"u}r Luft- und Raumfahrt - Lilienthal-Oberth (DGLR)}, address = {Bonn}, pages = {1441 -- 1450}, year = {2006}, language = {en} } @inproceedings{BraunBouckeBallmann2005, author = {Braun, Carsten and Boucke, Alexander and Ballmann, Josef}, title = {Numerical prediction of the wing deformation of a high speed transport aircraft type wind tunnel model by direct aeroelastic simulation}, series = {Conference proceedings : CEAS/AIAA/DGLR International Forum on Aeroelasticity and Structural Dynamics IFASD 2005 : M{\"u}nchen, June 28 - July 1, 2005. DGLR-Bericht. 2005,04}, booktitle = {Conference proceedings : CEAS/AIAA/DGLR International Forum on Aeroelasticity and Structural Dynamics IFASD 2005 : M{\"u}nchen, June 28 - July 1, 2005. DGLR-Bericht. 2005,04}, publisher = {DGLR}, address = {Bonn}, isbn = {3-932182-43-X}, pages = {1 CD-ROM}, year = {2005}, language = {en} } @incollection{BraunBouckeBallmann2005, author = {Braun, Carsten and Boucke, Alexander and Ballmann, Josef}, title = {Numerical study of the influence of dynamic pressure and deflected ailerons on the deformation of a high speed wing model}, series = {High performance computing in science and engineering '04. Transactions of the High Performance Computing Center Stuttgart (HLRS) 2004 / Eds.: Egon Krause ...}, booktitle = {High performance computing in science and engineering '04. Transactions of the High Performance Computing Center Stuttgart (HLRS) 2004 / Eds.: Egon Krause ...}, publisher = {Springer}, address = {Berlin}, isbn = {3-540-22943-4}, pages = {225 -- 236}, year = {2005}, language = {en} } @incollection{BallmannBouckeBraun2003, author = {Ballmann, Josef and Boucke, Alexander and Braun, Carsten}, title = {Aeroelastic sensitivity in the transonic regime}, series = {Symposium Transsonicum IV : proceedings of the IUTAM symposium held in G{\"o}ttingen, Germany, 2 - 6 September 2002 / ed. by Helmut Sobieczky. Fluid mechanics and its applications. Vol. 73}, booktitle = {Symposium Transsonicum IV : proceedings of the IUTAM symposium held in G{\"o}ttingen, Germany, 2 - 6 September 2002 / ed. by Helmut Sobieczky. Fluid mechanics and its applications. Vol. 73}, publisher = {Kluwer Academic}, address = {Dordrecht}, isbn = {978-94-010-3998-7}, pages = {225 -- 236}, year = {2003}, language = {en} } @incollection{BraunBouckeHankeetal.2003, author = {Braun, Carsten and Boucke, Alexander and Hanke, M. and Karavas, Alexandros and Ballmann, Josef}, title = {Prediction of the model deformation of a high speed transport aircraft type wing by direct aeroelastic simulation}, series = {High performance computing in science and engineering '03. Transactions of the High Performance Computing Center Stuttgart (HLRS) 2003 / Eds.: Egon Krause ...}, booktitle = {High performance computing in science and engineering '03. Transactions of the High Performance Computing Center Stuttgart (HLRS) 2003 / Eds.: Egon Krause ...}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-540-40850-5}, pages = {331 -- 342}, year = {2003}, language = {de} } @incollection{BrittenBraunHesseetal.2003, author = {Britten, G. and Braun, Carsten and Hesse, M. and Ballmann, Josef}, title = {Computational aeroelasticity with reduced structural models}, series = {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}, booktitle = {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}, publisher = {Springer}, address = {Berlin}, isbn = {3-540-40209-8}, pages = {275 -- 299}, year = {2003}, language = {en} } @techreport{ReimerWellmerBraunetal.2007, author = {Reimer, Lars and Wellmer, Georg and Braun, Carsten and Ballmann, Josef}, title = {Aerodynamische Simulation und Optimierung in der Flugzeugentwicklung. Teilvorhabenbezeichnung: Aerodynamische Optimierung unter Ber{\"u}cksichtigung von Struktureigenschaften auf der Basis reduzierter Strukturmodelle, Verbundvorhaben MEGADESIGN. Schlussbericht. Berichtszeitraum: 01.06.2003-31.05.2007. BMBF-Forschungsbericht}, pages = {41 S.: Ill., graph. Darst.}, year = {2007}, language = {de} } @book{Braun2007, author = {Braun, Carsten}, title = {Ein modulares Verfahren f{\"u}r die numerische aeroelastische Analyse von Luftfahrzeugen}, pages = {VI, 199 S.}, year = {2007}, abstract = {Aachen, Techn. Hochschule, Diss., 2007}, language = {de} } @article{JordanKruegerWillmesetal.2011, author = {Jordan, Sabine D. and Kr{\"u}ger, Markus and Willmes, Diana M. and Redemann, Nora and Wunderlich, F. Thomas and Br{\"o}nneke, Hella S. and Merkwirth, Carsten and Kashkar, Hamid and Olkkonen, Vesa M. and B{\"o}ttger, Thomas and Braun, Thomas and Seibler, Jost and Br{\"u}ning, Jens C.}, title = {Obesity-induced overexpression of miRNA-143 inhibits insulin-stimulated AKT activation and impairs glucose metabolism}, series = {Nature Cell Biology}, volume = {13}, journal = {Nature Cell Biology}, number = {4}, publisher = {Nature}, address = {New York}, issn = {1465-7392}, doi = {10.1038/ncb2211}, pages = {434 -- 446}, year = {2011}, abstract = {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.}, language = {en} } @article{NeuJanserKhatibietal.2016, author = {Neu, Eugen and Janser, Frank and Khatibi, Akbar A. and Braun, Carsten and Orifici, Adrian C.}, title = {Operational Modal Analysis of a wing excited by transonic flow}, series = {Aerospace Science and Technology}, volume = {49}, journal = {Aerospace Science and Technology}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1270-9638}, doi = {10.1016/j.ast.2015.11.032}, pages = {73 -- 79}, year = {2016}, abstract = {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.}, language = {en} } @inproceedings{SchildtBraunMarcocca2017, author = {Schildt, P. and Braun, Carsten and Marcocca, P.}, title = {Flight testing the extra 330LE flying testbed}, series = {48th Annual International Symposium of the Society of Flight Test Engineers 2017}, booktitle = {48th Annual International Symposium of the Society of Flight Test Engineers 2017}, isbn = {978-151085387-4}, pages = {349 -- 362}, year = {2017}, language = {en} } @inproceedings{LudowicyRingsFingeretal.2018, author = {Ludowicy, Jonas and Rings, Ren{\´e} and Finger, Felix and Braun, Carsten}, title = {Sizing Studies of Light Aircraft with Serial Hybrid Propulsion Systems}, series = {Luft- und Raumfahrt - Digitalisierung und Vernetzung : Deutscher Luft- und Raumfahrtkongress 2018. 4. - 6. September 2018 - Friedrichshafen}, booktitle = {Luft- und Raumfahrt - Digitalisierung und Vernetzung : Deutscher Luft- und Raumfahrtkongress 2018. 4. - 6. September 2018 - Friedrichshafen}, pages = {11 S.}, year = {2018}, language = {en} } @inproceedings{FingerGoettenBraun2018, author = {Finger, Felix and G{\"o}tten, Falk and Braun, Carsten}, title = {Initial Sizing for a Family of Hybrid-Electric VTOL General Aviation Aircraft}, series = {67. Deutscher Luft- und Raumfahrtkongress 2018}, booktitle = {67. Deutscher Luft- und Raumfahrtkongress 2018}, pages = {14 S.}, year = {2018}, language = {en} } @inproceedings{LudowicyRingsFingeretal.2018, author = {Ludowicy, Jonas and Rings, Ren{\´e} and Finger, Felix and Braun, Carsten}, title = {Sizing Studies of Light Aircraft with Parallel Hybrid Propulsion Systems}, series = {Deutscher Luft- und Raumfahrtkongress 2018}, booktitle = {Deutscher Luft- und Raumfahrtkongress 2018}, doi = {10.25967/480227}, pages = {15 S.}, year = {2018}, language = {en} } @article{GoettenFingerHavermannetal.2018, author = {G{\"o}tten, Falk and Finger, Felix and Havermann, Marc and Braun, Carsten and Gomez, Francisco and Bill, C.}, title = {On the flight performance impact of landing gear drag reduction methods for unmanned air vehicles}, series = {Deutscher Luft- und Raumfahrtkongress 2018}, journal = {Deutscher Luft- und Raumfahrtkongress 2018}, publisher = {DGLR}, address = {Bonn}, doi = {10.25967/480058}, pages = {11 S.}, year = {2018}, abstract = {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.}, language = {en} } @inproceedings{FingerBraunBil2018, author = {Finger, Felix and Braun, Carsten and Bil, Cees}, title = {Case studies in initial sizing for hybrid-electric general aviation aircraft}, series = {2018 AIAA/IEEE Electric Aircraft Technologies Symposium, Cincinnati, Ohio}, booktitle = {2018 AIAA/IEEE Electric Aircraft Technologies Symposium, Cincinnati, Ohio}, doi = {10.2514/6.2018-5005}, year = {2018}, language = {en} } @article{FingerBraunBil2018, author = {Finger, Felix and Braun, Carsten and Bil, Cees}, title = {Impact of electric propulsion technology and mission requirements on the performance of VTOL UAVs}, series = {CEAS Aeronautical Journal}, volume = {10}, journal = {CEAS Aeronautical Journal}, number = {3}, publisher = {Springer}, issn = {1869-5582 print}, doi = {10.1007/s13272-018-0352-x}, pages = {843}, year = {2018}, abstract = {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.}, language = {en} } @inproceedings{FingerBraunBil2017, author = {Finger, Felix and Braun, Carsten and Bil, Cees}, title = {The Impact of Electric Propulsion on the Performance of VTOL UAVs}, series = {Deutscher Luft- und Raumfahrtkongress 2017, DLRK , M{\"u}nchen}, booktitle = {Deutscher Luft- und Raumfahrtkongress 2017, DLRK , M{\"u}nchen}, year = {2017}, language = {en} } @inproceedings{FingerBraunBil2017, author = {Finger, Felix and Braun, Carsten and Bil, Cees}, title = {A Review of Configuration Design for Distributed Propulsion Transitioning VTOL Aircraft}, series = {Asia-Pacific International Symposium on Aerospace Technology 2017, APISAT 2017, Seoul, Korea}, booktitle = {Asia-Pacific International Symposium on Aerospace Technology 2017, APISAT 2017, Seoul, Korea}, pages = {15 Seiten}, year = {2017}, language = {en} } @inproceedings{FingerBraunBil2018, author = {Finger, Felix and Braun, Carsten and Bil, Cees}, title = {An Initial Sizing Methodology for Hybrid-Electric Light Aircraft}, series = {AIAA AVIATION Forum 2018 Aviation Technology, Integration, and Operations Conference, Atlanta, Georgia, June 25 - 29, 2018}, booktitle = {AIAA AVIATION Forum 2018 Aviation Technology, Integration, and Operations Conference, Atlanta, Georgia, June 25 - 29, 2018}, doi = {10.2514/6.2018-4229}, year = {2018}, language = {en} }