@article{Mertens1998, author = {Mertens, Josef}, title = {Multi point design challenges for supersonic transports}, series = {Fluid dynamics research on supersonic aircraft : this report is a compilation of the edited proceedings of the special course on "Fluid dynamics research on supersonic aircraft" held at the Karman Institute for Fluid Dynamics (VKI) in Rhode-Saint-Genese, Belgium, 25-29 May 1998}, journal = {Fluid dynamics research on supersonic aircraft : this report is a compilation of the edited proceedings of the special course on "Fluid dynamics research on supersonic aircraft" held at the Karman Institute for Fluid Dynamics (VKI) in Rhode-Saint-Genese, Belgium, 25-29 May 1998}, publisher = {Research and Technology Organization}, address = {Neuilly-sur-Seine}, isbn = {92-837-1007-X}, pages = {8.1 -- 8.12}, year = {1998}, language = {en} } @article{Mertens1992, author = {Mertens, Josef}, title = {Laminar flow for supersonic transports}, series = {Proceedings : March 16 - 18, 1992, Congress Centrum, Hamburg, Federal Republic of Germany / organized jointly by: Deutsche Gesellschaft f{\"u}r Luft- und Raumfahrt e.V. ... [Programme committee J. Szodruch ...]}, journal = {Proceedings : March 16 - 18, 1992, Congress Centrum, Hamburg, Federal Republic of Germany / organized jointly by: Deutsche Gesellschaft f{\"u}r Luft- und Raumfahrt e.V. ... [Programme committee J. Szodruch ...]}, publisher = {DGLR}, address = {Bonn}, isbn = {3-922010-73-3}, pages = {319 -- 323}, year = {1992}, language = {en} } @article{Mertens1998, author = {Mertens, Josef}, title = {Aerodynamische Ziele des Adaptiven Fl{\"u}gels (ADIF).}, series = {DGLR-Jahrbuch 1998 Bd. 1}, journal = {DGLR-Jahrbuch 1998 Bd. 1}, pages = {47 -- 52}, year = {1998}, language = {de} } @article{Mertens1999, author = {Mertens, Josef}, title = {Einige herausragende Ergebnisse des Technologieprogramms "Reduktion des Aerodynamischen Widerstands (RaWid)"}, series = {DGLR-Jahrbuch 1999 Bd. 3}, journal = {DGLR-Jahrbuch 1999 Bd. 3}, pages = {1461 -- 1468}, year = {1999}, language = {de} } @book{Mertens1999, author = {Mertens, Josef}, title = {Reduktion des aerodynamischen Widerstands (RaWid) : Abschlußbericht ; Laufzeit des Vorhaben, Berichtszeitraum: 01.07.1995 bis 31.12.1998 / Verf.: J. Mertens}, publisher = {DaimlerChrysler Aerospare Airbus GmbH}, address = {Hamburg}, pages = {31 Bl. : Ill., graph. Darst.}, year = {1999}, language = {de} } @book{Mertens1999, author = {Mertens, Josef}, title = {Reduktion des aerodynamischen Widerstands (RaWid) : Abschlußbericht ; Laufzeit des Vorhaben, Berichtszeitraum: 01.07.1995 bis 31.12.1998 / Verf.: J. Mertens}, publisher = {DaimlerChrysler Aerospare Airbus GmbH}, address = {Hamburg}, pages = {Elektronische Ressource 31 p. = 1,38 Mb. text and}, year = {1999}, language = {de} } @inproceedings{Mertens1999, author = {Mertens, Josef}, title = {Some important results of the technology programme RaWid}, series = {New Results in Numerical and Experimental Fluid Mechanics : Contributions to the 11th AG STAB/DGLR Symposium Berlin, Germany 1998. - Vol. 2. - (Notes on Numerical Fluid Mechanics ; 72)}, booktitle = {New Results in Numerical and Experimental Fluid Mechanics : Contributions to the 11th AG STAB/DGLR Symposium Berlin, Germany 1998. - Vol. 2. - (Notes on Numerical Fluid Mechanics ; 72)}, editor = {Nitsche, Wolfgang}, publisher = {Springer Fachmedien}, address = {Wiesbaden}, isbn = {978-3-663-10903-7 (Print)}, doi = {10.1007/978-3-663-10901-3_41}, pages = {315 -- 322}, year = {1999}, language = {en} } @incollection{MertensBecker1989, author = {Mertens, Josef and Becker, K.}, title = {Numerical solution of flow equations : an aircraft designer's view}, series = {Nonlinear hyperbolic equations - theory, computation methods, and applications : proceedings of the 2nd International Conference on Nonlinear Hyperbolic Problems, Aachen, FRG, March 14 to 18, 1988. - (Notes on Numerical Fluid Mechanics ; 24)}, booktitle = {Nonlinear hyperbolic equations - theory, computation methods, and applications : proceedings of the 2nd International Conference on Nonlinear Hyperbolic Problems, Aachen, FRG, March 14 to 18, 1988. - (Notes on Numerical Fluid Mechanics ; 24)}, editor = {Ballmann, Josef}, publisher = {Vieweg}, address = {Braunschweig}, isbn = {3-528-08098-1}, doi = {10.1007/978-3-322-87869-4_41}, pages = {403 -- 412}, year = {1989}, abstract = {Today the most accurate and cost effective industrial codes used in aircraft design are based on the full potential equation coupled with boundary layer equations. However, these are not capable to solve complicated three-dimensional problems of vortical flows and shocks. On the other hand Euler and Navier-Stokes codes are too expensive and not accurate enough for design purposes, especially in regard of drag and interference prediction. The reasons for these deficiencies are investigated and a way to overcome them by future developments is demonstrated.}, language = {en} } @article{MertensHenke2001, author = {Mertens, Josef and Henke, Rolf}, title = {Adaptive technologies for future civil air transport}, series = {Air \& Space Europe. 3 (2001), H. 3-4}, journal = {Air \& Space Europe. 3 (2001), H. 3-4}, isbn = {1247-5793}, pages = {80 -- 82}, year = {2001}, language = {en} } @article{MertensHuenecke1988, author = {Mertens, Josef and H{\"u}necke, Klaus}, title = {Experimentelle Untersuchung zur Landeeigenschaft von Hyperschall-Flugger{\"a}ten / H{\"u}necke, Klaus ; Mertens, Josef}, series = {DGLR-Jahrbuch 1988 Bd. 1}, journal = {DGLR-Jahrbuch 1988 Bd. 1}, pages = {706}, year = {1988}, language = {de} } @article{MertensKelmVelden1999, author = {Mertens, Josef and Kelm, R. and Velden, A. van der}, title = {Interdisziplin{\"a}re Auslegung eines Verkehrsflugzeugfl{\"u}gels}, series = {DGLR-Jahrbuch 1999 Bd. 3}, journal = {DGLR-Jahrbuch 1999 Bd. 3}, pages = {1605 -- 1610}, year = {1999}, language = {de} } @article{MertensKlevenhusenJakob1987, author = {Mertens, Josef and Klevenhusen, K. D. and Jakob, H.}, title = {Accurate Transonic Wave Drag Prediction Using Simple Physical Models}, series = {AIAA-Journal. 25 (1987), H. 6}, journal = {AIAA-Journal. 25 (1987), H. 6}, isbn = {0001-1452}, pages = {799 -- 805}, year = {1987}, language = {en} } @misc{MertensLajain2002, author = {Mertens, Josef and Lajain, Henri}, title = {Method of fabricating leading edge nose structures of aerodynamic surfaces : patent no.: US 6,415,510 B2 ; date of patent: Jul. 9, 2002}, publisher = {United States Patent and Trademark Office}, address = {[Washington, DC]}, pages = {12 S. : Ill.}, year = {2002}, language = {en} } @article{MertensRoeger2000, author = {Mertens, Josef and R{\"o}ger, Wolf}, title = {F-Schlepp: Problem Taumelschwingung}, series = {Aerokurier. 44 (2000), H. 10}, journal = {Aerokurier. 44 (2000), H. 10}, isbn = {0341-1281}, pages = {73 -- 73}, year = {2000}, language = {de} } @misc{MertensVeldenKelm2006, author = {Mertens, Josef and Velden, Alexander van der and Kelm, Roland}, title = {Flugzeug mit Fl{\"u}geln, deren maximaler Auftrieb durch steuerbare Fl{\"u}gelkomponenten ver{\"a}nderbar ist : Offenlegungsschrift DE102004045732 ; Offenlegungstag: 30.03.2006 = Aircraft with wings whose maximum lift can be altered by controllable wing components}, publisher = {Deutsches Patent- und Markenamt}, address = {M{\"u}nchen}, pages = {6 S. : Ill.}, year = {2006}, language = {de} } @book{MertensVeldenKelmetal.2000, author = {Mertens, Josef and Velden, Alexander van der and Kelm, Roland and Kokan, David}, title = {Application of MDO to large subsonic transport aircraft}, publisher = {American Institute of Aeronautics and Astronautics}, address = {Reston, Va.}, pages = {12 S. : zahlr. Ill. u. graph. Darst.}, year = {2000}, language = {en} } @article{MeyerGranrathFeyerletal.2021, author = {Meyer, Max-Arno and Granrath, Christian and Feyerl, G{\"u}nter and Richenhagen, Johannes and Kaths, Jakob and Andert, Jakob}, title = {Closed-loop platoon simulation with cooperative intelligent transportation systems based on vehicle-to-X communication}, series = {Simulation Modelling Practice and Theory}, volume = {106}, journal = {Simulation Modelling Practice and Theory}, number = {Art. 102173}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1569-190X}, doi = {10.1016/j.simpat.2020.102173}, year = {2021}, language = {en} } @inproceedings{MoehrenBergmannJanseretal.2023, author = {M{\"o}hren, Felix and Bergmann, Ole and Janser, Frank and Braun, Carsten}, title = {On the determination of harmonic propeller loads}, series = {AIAA SCITECH 2023 Forum}, booktitle = {AIAA SCITECH 2023 Forum}, publisher = {AIAA}, doi = {10.2514/6.2023-2404}, pages = {12 Seiten}, year = {2023}, abstract = {Dynamic loads significantly impact the structural design of propeller blades due to fatigue and static strength. Since propellers are elastic structures, deformations and aerodynamic loads are coupled. In the past, propeller manufacturers established procedures to determine unsteady aerodynamic loads and the structural response with analytical steady-state calculations. According to the approach, aeroelastic coupling primarily consists of torsional deformations. They neglect bending deformations, deformation velocities, and inertia terms. This paper validates the assumptions above for a General Aviation propeller and a lift propeller for urban air mobility or large cargo drones. Fully coupled reduced-order simulations determine the dynamic loads in the time domain. A quasi-steady blade element momentum approach transfers loads to one-dimensional finite beam elements. The simulation results are in relatively good agreement with the analytical method for the General Aviation propeller but show increasing errors for the slender lift propeller. The analytical approach is modified to consider the induced velocities. Still, inertia and velocity proportional terms play a significant role for the lift propeller due to increased elasticity. The assumption that only torsional deformations significantly impact the dynamic loads of propellers is not valid. Adequate determination of dynamic loads of such designs requires coupled aeroelastic simulations or advanced analytical procedures.}, language = {en} } @article{MoehrenBergmannJanseretal.2023, author = {M{\"o}hren, Felix and Bergmann, Ole and Janser, Frank and Braun, Carsten}, title = {On the influence of elasticity on propeller performance: a parametric study}, series = {CEAS Aeronautical Journal}, volume = {14}, journal = {CEAS Aeronautical Journal}, publisher = {Springer Nature}, address = {Berlin}, issn = {1869-5590 (Online)}, doi = {10.1007/s13272-023-00649-y}, pages = {311 -- 323}, year = {2023}, abstract = {The aerodynamic performance of propellers strongly depends on their geometry and, consequently, on aeroelastic deformations. Knowledge of the extent of the impact is crucial for overall aircraft performance. An integrated simulation environment for steady aeroelastic propeller simulations is presented. The simulation environment is applied to determine the impact of elastic deformations on the aerodynamic propeller performance. The aerodynamic module includes a blade element momentum approach to calculate aerodynamic loads. The structural module is based on finite beam elements, according to Timoshenko theory, including moderate deflections. Several fixed-pitch propellers with thin-walled cross sections made of both isotropic and non-isotropic materials are investigated. The essential parameters are varied: diameter, disc loading, sweep, material, rotational, and flight velocity. The relative change of thrust between rigid and elastic blades quantifies the impact of propeller elasticity. Swept propellers of large diameters or low disc loadings can decrease the thrust significantly. High flight velocities and low material stiffness amplify this tendency. Performance calculations without consideration of propeller elasticity can lead to decreased efficiency. To avoid cost- and time-intense redesigns, propeller elasticity should be considered for swept planforms and low disc loadings.}, 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} }