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  - 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  - Kapoor, Hrshi
A1  - Boller, Christian
A1  - Giljohann, Sebastian
A1  - Braun, Carsten
T1  - Strategies for structural health monitoring implementation potential assessment in aircraft operational life extension considerations
T2  - 2nd International Symposium on NDT in Aerospace : November 22-24, 2010 Hamburg, Germany
Y1  - 2010
SN  - 978-3-940283-28-3
PB  - Dt. Gesellschaft für Zerstörungsfreie Prüfung
CY  - Berlin
ER  - 
TY  - CHAP
A1  - Kapoor, Hrshi
A1  - Braun, Carsten
A1  - Boller, Christian
ED  - Casciati, Fabio
T1  - Modelling and optimisation of maintenance intervals to realize structural health monitoring applications on aircraft
T2  - Structural health monitoring 2010 : proceedings of the Fifth European Workshop on Structural Health Monitoring held at Sorrento, Naples, Italy, June 28 - July 4, 2010 ; [EWSHM]
Y1  - 2010
SN  - 978-1-60595-024-2
SP  - 55
EP  - 63
PB  - DEStech Publ.
CY  - Lancaster, Pa.
ER  - 
TY  - CHAP
A1  - Reimer, Lars
A1  - Braun, Carsten
A1  - Wellmer, Georg
A1  - Behr, Marek
A1  - Ballmann, Josef
T1  - Development of a modular method for computational aero-structural analysis of aircraft
T2  - Summary of flow modulation and fluid-structure interaction findings. Results of the Collaborative Research Center SFB 401 at the RWTH Aachen University, Aachen, Germany, 1997-2008 / ed.: Wolfgang Schröder. Notes on numerical fluid mechanics and multidisciplinary design. Vol. 109
Y1  - 2010
SN  - 978-3-642-04087-0
SP  - 205
EP  - 238
PB  - Springer
CY  - Berlin
ER  - 
TY  - CHAP
A1  - Reimer, Lars
A1  - Wellmer, Georg
A1  - Braun, Carsten
A1  - Ballmann, Josef
T1  - Computational methods for aero-structural analysis and optimisation of aircrafts based on reduced-order structural models
T2  - MEGADESIGN and MegaOpt - German initiatives for aerodynamic simulation and optimization in aircraft design. Results of the closing symposium of the MEGADESIGN and MegaOpt projects, Braunschweig, Germany, 23 - 24 May, 2007 / Norbert Kroll ... (Eds.) Notes on numerical fluid mechanics and multidisciplinary design. Vol. 107
N2  - In this part of the MEGADESIGN project, aeroelastic effects are introduced into the aerodynamic analysis of aircrafts by coupling DLR’s flow solvers TAU and FLOWer to a Timoshenko-beam solver. The emerging aeroelastic solvers and a method for the automatic identification of Timoshenko-beam models for wing-box structures were integrated into a simulation environment enabling the combined optimisation of aerodynamic wing shape and structure.
Y1  - 2009
SN  - 978-3-642-04092-4
SP  - 135
EP  - 150
PB  - Springer
CY  - Berlin
ER  - 
TY  - CHAP
A1  - Reimer, Lars
A1  - Braun, Carsten
A1  - Chen, B.-H.
A1  - Ballmann, Josef
T1  - Computational aeroelastic analysis and design of the HIRENASD wind tunnel wing model and tests
T2  - Proceedings / IFASD 2007, CEAS/AIAA/KTH International Forum on Aeroelasticity and Structural Dynamics : June 18 - 21, 2007, Stockholm, Sweden
Y1  - 2007
PB  - KTH
CY  - Stockholm
ER  - 
TY  - CHAP
A1  - Wellmer, Georg
A1  - Chen, B.-H.
A1  - Braun, Carsten
A1  - Ballmann, Josef
T1  - Numerical prediction of aeroelastic effects on twin-sting-rig mounted models for rear fuselage and empennage flow investigation in transonic windtunnel
T2  - Proceedings / IFASD 2007, CEAS/AIAA/KTH International Forum on Aeroelasticity and Structural Dynamics, June 18 - 21, 2007, Stockholm, Sweden
Y1  - 2007
PB  - KTH
CY  - Stockholm
ER  - 
TY  - CHAP
A1  - Reimer, Lars
A1  - Braun, Carsten
A1  - Ballmann, Josef
T1  - Computational study of the aeroelastic equilibrium configuration of a swept wind tunnel wing model in subsonic flow
T2  - High performance computing in science and engineering '06. Transactions of the High Performance Computing Center Stuttgart (HLRS) 2006 /  Wolfgang E. Nagel ... Eds.
N2  - In the Collaborative Research Center SFB 401 at RWTH Aachen University, the numerical aeroelastic method SOFIA for direct numerical aeroelastic simulation is being progressively developed. Numerical results obtained by applying SOFIA were compared with measured data of static and dynamic aeroelastic wind tunnel tests for an elastic swept wing in subsonic flow.
Y1  - 2007
SN  - 978-3-540-36165-7
SP  - 421
EP  - 434
PB  - Springer
CY  - Berlin [u.a.]
ER  -