TY - CHAP A1 - Loeb, Horst W. A1 - Schartner, Karl-Heinz A1 - Seboldt, Wolfgang A1 - Dachwald, Bernd A1 - Streppel, Joern A1 - Meusemann, Hans A1 - Schülke, Peter T1 - SEP for a lander mission to the jovian moon europa T2 - 57th International Astronautical Congress N2 - Under DLR-contract, Giessen University and DLR Cologne are studying solar-electric propulsion missions (SEP) to the outer regions of the solar system. The most challenging reference mission concerns the transport of a 1.35-tons chemical lander spacecraft into an 80-RJ circular orbit around Jupiter, which would enable to place a 375 kg lander with 50 kg of scientific instruments on the surface of the icy moon "Europa". Thorough analyses show that the best solution in terms of SEP launch mass times thrusting time would be a two-stage EP module and a triple-junction solar array with concentrators which would be deployed step by step. Mission performance optimizations suggest to propel the spacecraft in the first EP stage by 6 gridded ion thrusters, running at 4.0 kV of beam voltage, which would save launch mass, and in the second stage by 4 thrusters with 1.25 to 1.5 kV of positive high voltage saving thrusting time. In this way, the launch mass of the spacecraft would be kept within 5.3 tons. Without a launcher's C3 and interplanetary gravity assists, Jupiter might be reached within about 4 yrs. The spiraling-down into the parking orbit would need another 1.8 yrs. This "large mission" can be scaled down to a smaller one, e.g., by halving all masses, the solar array power, and the number of thrusters. Due to their reliability, long lifetime and easy control, RIT-22 engines have been chosen for mission analysis. Based on precise tests, the thruster performance has been modeled. Y1 - 2006 U6 - http://dx.doi.org/10.2514/6.IAC-06-C4.4.04 N1 - 57th International Astronautical Congress, 02 October 2006 - 06 October 2006, Valencia, Spain. SP - 1 EP - 12 ER - TY - JOUR A1 - Loeb, Horst Wolfgang A1 - Schartner, Karl-Heinz A1 - Dachwald, Bernd A1 - Ohndorf, Andreas A1 - Seboldt, Wolfgang T1 - Interstellar heliopause probe JF - Труды МАИ N2 - There is common agreement within the scientific community that in order to understand our local galactic environment it will be necessary to send a spacecraft into the region beyond the solar wind termination shock. Considering distances of 200 AU for a new mission, one needs a spacecraft traveling at a speed of close to 10 AU/yr in order to keep the mission duration in the range of less than 25 yrs, a transfer time postulated by European Space Agency (ESA). Two propulsion options for the mission have been proposed and discussed so far: the solar sail propulsion and the ballistic/radioisotope-electric propulsion (REP). As a further alternative, we here investigate a combination of solar-electric propulsion (SEP) and REP. The SEP stage consists of six 22-cms diameter RIT-22 ion thrusters working with a high specific impulse of 7377 s corresponding to a positive grid voltage of 5 kV. Solar power of 53 kW at begin of mission (BOM) is provided by a lightweight solar array. Y1 - 2012 IS - 60 SP - 2 EP - 2 PB - Moskauer Staatliches Luftfahrtinstitut (МАИ) CY - Moskau ER - TY - CHAP A1 - Loeb, Horst Wolfgang A1 - Schartner, Karl-Heinz A1 - Dachwald, Bernd A1 - Seboldt, Wolfgang T1 - SEP-Sample return from a main belt asteroid T2 - 30th International Electric Propulsion Conference N2 - By DLR-contact, sample return missions to the large main-belt asteroid “19, Fortuna” have been studied. The mission scenario has been based on three ion thrusters of the RIT-22 model, which is presently under space qualification, and on solar arrays equipped with triple-junction GaAs solar cells. After having designed the spacecraft, the orbit-to-orbit trajectories for both, a one-way SEP mission with a chemical sample return and an all-SEP return mission, have been optimized using a combination of artificial neural networks with evolutionary algorithms. Additionally, body-to-body trajectories have been investigated within a launch period between 2012 and 2015. For orbit-to-orbit calculation, the launch masses of the hybrid mission and of the all-SEP mission resulted in 2.05 tons and 1.56 tons, respectively, including a scientific payload of 246 kg. For the related transfer durations 4.14 yrs and 4.62 yrs were obtained. Finally, a comparison between the mission scenarios based on SEP and on NEP have been carried out favouring clearly SEP. Y1 - 2007 SP - 1 EP - 11 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 - 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 - CHAP A1 - Ludowicy, Jonas A1 - Rings, René A1 - Finger, Felix A1 - Braun, Carsten A1 - Bil, Cees T1 - Impact of Propulsion Technology Levels on the Sizing and Energy Consumption for Serial HybridElectric General Aviation Aircraft T2 - Asia Pacific International Symposium on Aerospace Technology. APISAT 2019 Y1 - 2019 ER - TY - JOUR A1 - Lyons, W. Berry A1 - Mikucki, Jill A. A1 - German, Laura A. A1 - Welch, Kathleen A. A1 - Welch, Susan A. A1 - Gardener, Christopher B. A1 - Tulaczyk, Slawek M. A1 - Pettit, Erin C. A1 - Kowalski, Julia A1 - Dachwald, Bernd T1 - The Geochemistry of Englacial Brine from Taylor Glacier, Antarctica JF - Journal of Geophysical Research: Biogeosciences Y1 - 2019 U6 - http://dx.doi.org/10.1029/2018JG004411 SN - 2169-8961 PB - Wiley CY - Hoboken ER - TY - CHAP A1 - Macdonald, Malcolm A1 - McGrath, C. A1 - Appourchaux, T. A1 - Dachwald, Bernd A1 - Finsterle, W. A1 - Gizon, L. A1 - Liewer, P. C. A1 - McInnes, Colin R. A1 - Mengali, G. A1 - Seboldt, W. A1 - Sekii, T. A1 - Solanki, S. K. A1 - Velli, M. A1 - Wimmer-Schweingruber, R. F. A1 - Spietz, Peter A1 - Reinhard, Ruedeger ED - Macdonald, Malcolm T1 - Gossamer roadmap technology reference study for a solar polar mission T2 - Advances in solar sailing N2 - A technology reference study for a solar polar mission is presented. The study uses novel analytical methods to quantify the mission design space including the required sail performance to achieve a given solar polar observation angle within a given timeframe and thus to derive mass allocations for the remaining spacecraft sub-systems, that is excluding the solar sail sub-system. A parametric, bottom-up, system mass budget analysis is then used to establish the required sail technology to deliver a range of science payloads, and to establish where such payloads can be delivered to within a given timeframe. It is found that a solar polar mission requires a solar sail of side-length 100–125 m to deliver a ‘sufficient value’ minimum science payload, and that a 2.5 μm sail film substrate is typically required, however the design is much less sensitive to the boom specific mass. Y1 - 2014 SN - 978-3-642-34906-5 U6 - http://dx.doi.org/10.1007/978-3-642-34907-2_17 SP - 243 EP - 257 PB - Springer CY - Berlin, Heidelberg ER - TY - JOUR A1 - Maiwald, Volker A1 - Dachwald, Bernd T1 - Mission Design for a Multiple-Rendezvous Mission to Jupiter's Trojans Y1 - 2010 N1 - COSPAR 2010 ; 38th COSPAR Scientific Assembly. Held 18-25 July 2010 in Bremen, Germany [Abstract] SP - 3 ER - TY - JOUR A1 - Matheis, Anton A1 - Röth, Thilo A1 - Wagner, Manfred T1 - Studentenprojekt "Capro" – eine virtuelle Sportwagenstudie "Vision 2015" N2 - Design- und Karosseriebaustudenten der FH Aachen entwickeln gemeinsam mit externen Fachleuten unter Einsatz virtueller Entwicklungswerkzeuge ein Konzept für einen Sportwagen KW - Karosseriebau KW - Sportwagen KW - Kraftfahrzeugbau KW - Studentenprojekt KW - Virtuelle Fahrzeugentwicklung KW - car body construction Y1 - 2005 ER - TY - JOUR A1 - Mathiak, Gerhard A1 - Plescher, Engelbert A1 - Willnecker, Rainer T1 - Liquid metal diffusion experiments in microgravity - Vibrational effects JF - Measurement science and technology Y1 - 2005 U6 - http://dx.doi.org/10.1088/0957-0233/16/2/003 SN - 0957-0233 VL - Vol. 16 IS - No. 2 SP - 336 ER - TY - CHAP A1 - Mathiak, Gerhard A1 - Plescher, Engelbert A1 - Willnecker, Rainer T1 - Parabolic flight experiments about vibrational effects on diffusion experiments T2 - 54th International Astronautical Congress of the International Astronautical Federation (IAF) : Bremen, 29 Sept. 2003 through 3 Oct. 2003 ; vol. 1 Y1 - 2003 SP - 4389 EP - 4396 ER - TY - JOUR A1 - Mathiak, Gerhard A1 - Willnecker, Rainer A1 - Plescher, Engelbert T1 - Vibrational effects on diffusion experiments JF - Microgravity science and technology : international journal for microgravity research and applications Y1 - 2005 SN - 0938-0108 VL - Vol. 15 IS - No. 1 SP - 295 EP - 300 ER - TY - JOUR A1 - Maurischat, Andreas T1 - Algebraic independence of the Carlitz period and its hyperderivatives JF - Journal of Number Theory KW - Drinfeld modules KW - Periods KW - t-modules KW - Transcendence KW - Higher derivations Y1 - 2022 U6 - http://dx.doi.org/10.1016/j.jnt.2022.01.006 SN - 0022-314X VL - 240 SP - 145 EP - 162 PB - Elsevier CY - Orlando, Fla. ER - TY - JOUR A1 - Maurischat, Andreas T1 - Algebraic independence of the Carlitz period and its hyperderivatives KW - Drinfeld modules KW - t-modules KW - Transcendence KW - Hyperdifferentials Y1 - 2021 N1 - Zweitveröffentlichung. Verlagsveröffentlichung: https://doi.org/10.1016/j.jnt.2022.01.006 SP - 1 EP - 12 ER - TY - JOUR A1 - Maurischat, Andreas A1 - Perkins, Rudolph T1 - Taylor coefficients of Anderson generating functions and Drinfeld torsion extensions N2 - We generalize our work on Carlitz prime power torsion extension to torsion extensions of Drinfeld modules of arbitrary rank. As in the Carlitz case, we give a description of these extensions in terms of evaluations of Anderson generating functions and their hyperderivatives at roots of unity. We also give a direct proof that the image of the Galois representation attached to the p-adic Tate module lies in the p-adic points of the motivic Galois group. This is a generalization of the corresponding result of Chang and Papanikolas for the t-adic case. Y1 - 2020 U6 - http://dx.doi.org/10.1142/S1793042122500099 IS - Vol. 18, No. 01 SP - 113 EP - 130 PB - World Scientific CY - Singapur ER - TY - JOUR A1 - McArdell, Brian W. A1 - Bartelt, Perry A1 - Kowalski, Julia T1 - Field observations of basal forces and fluid pore pressure in a debris flow JF - Geophysical Research Letters (GRL) N2 - Using results from an 8 m2 instrumented force plate we describe field measurements of normal and shear stresses, and fluid pore pressure for a debris flow. The flow depth increased from 0.1 to 1 m within the first 12 s of flow front arrival, remained relatively constant until 100 s, and then gradually decreased to 0.5 m by 600 s. Normal and shear stresses and pore fluid pressure varied in-phase with the flow depth. Calculated bulk densities are ρb = 2000–2250 kg m−3 for the bulk flow and ρf = 1600–1750 kg m−3 for the fluid phase. The ratio of effective normal stress to shear stress yields a Coulomb basal friction angle of ϕ = 26° at the flow front. We did not find a strong correlation between the degree of agitation in the flow, estimated using the signal from a geophone on the force plate, and an assumed dynamic pore fluid pressure. Our data support the idea that excess pore-fluid pressures are long lived in debris flows and therefore contribute to their unusual mobility. KW - debris flow Y1 - 2007 SN - 0094-8276 VL - 34 IS - 7 ER - TY - CHAP A1 - McInnes, Colin R. A1 - Bothmer, Volker A1 - Dachwald, Bernd A1 - Geppert, Ulrich R. M. E. A1 - Heiligers, Jeannette A1 - Hilgers, Alan A1 - Johnson, Les A1 - Macdonald, Malcolm A1 - Reinhard, Ruedeger A1 - Seboldt, Wolfgang A1 - Spietz, Peter T1 - Gossamer roadmap technology reference study for a Sub-L1 Space Weather Mission T2 - Advances in solar sailing N2 - A technology reference study for a displaced Lagrange point space weather mission is presented. The mission builds on previous concepts, but adopts a strong micro-spacecraft philosophy to deliver a low mass platform and payload which can be accommodated on the DLR/ESA Gossamer-3 technology demonstration mission. A direct escape from Geostationary Transfer Orbit is assumed with the sail deployed after the escape burn. The use of a miniaturized, low mass platform and payload then allows the Gossamer-3 solar sail to potentially double the warning time of space weather events. The mission profile and mass budgets will be presented to achieve these ambitious goals. Y1 - 2014 SN - 978-3-642-34906-5 (Print) ; 978-3-642-34907-2 (E-Book) SP - 227 EP - 242 PB - Springer CY - Berlin [u.a.] ER - TY - CHAP A1 - Mertens, Josef T1 - Laminar leading edges: manufacturing, contamination, and operational aspects - results from the German RaWid programme N2 - RaWid was the German national technology programme on transonic aerodynamics and supporting technologies, lasting from 1995 to 1998. One of the main topics was laminar wing development. Besides aerodynamic design work, many operational aspects were investigated. A manufacturing concept was developed to be applied to operational laminar wings and empennages. It was built in a large scale manufacturing demonstrator with the aerodynamic shape of a 1,5 m section of the A320 fin nose. Tolerances in shape and roughness fulfilled all requirements. The construction can easily be adapted to varying stiffness and strength requirements. Weight and manufacturing costs are comparable to common nose designs. The mock-up to be designed in ALTTA is based on this manufacturing principle. Another critical point is contamination of suction surfaces. Several tests were performed to investigate perforated titanium suction surfaces at realistic operational conditions: - a one year flight test with a suction plate in the stagnation area of the Airbus "Beluga" - a one year test of several suction plates in a ground test near the airport - a one year test of a working suction ground test installation at all weather conditions. No critical results were found. There is no long term suction degradation visible. Icing conditions and ground de-icing fluids used on airports did not pose severe problems. Some problems detected require only respection of weak design constraints. KW - Laminare Strömung KW - Ansaugsystem KW - Profilumströmung KW - Laminarprofil KW - RaWid KW - hybrid laminar flow KW - suction systems KW - suction structure KW - contamination KW - operational aspects Y1 - 2000 ER - TY - CHAP A1 - Mertens, Josef ED - Sobieczky, H. T1 - Aerodynamic multi point design challenge T2 - New design concepts for high speed air transport.- (Courses and lectures / International Centre for Mechanical Sciences ; 366) N2 - In the chapter “Son of Concorde, a Technology Challenge” one of the new challenges for a Supersonic Commercial Transport (SCT) is multi-point design for the four main design points: - supersonic cruise - transonic cruise - take-off and landing - transonic acceleration. KW - Drag Reduction KW - Pitching Moment KW - Leading Edge Vortex KW - Wave Drag KW - Variable Geometry Y1 - 1997 SN - 3-2118-2815-X U6 - http://dx.doi.org/10.1007/978-3-7091-2658-5_4 SP - 53 EP - 67 PB - Springer CY - Wien [u.a.] ER - TY - CHAP A1 - Mertens, Josef ED - Sobieczky, H. T1 - Required aerodynamic technologies T2 - New design concepts for high speed air transport. - (Courses and lectures / International Centre for Mechanical Sciences ; 366) N2 - In the preceeding chapters on “Son of Concorde, a Technology Challenge” and “Aerodynamic Multipoint Design Challenge” it was explained, that a well balanced contribution of new technologies in all major disciplines is required for realisation of a new Supersonic Commercial Transport (SCT). One of these technologies - usually one of the most important for aircraft-is aerodynamics. Here, the required “pure” aerodynamic technologies are specified in more detail, according to our present knowledge. Increasing insight into the problems may change the balance of importance of the individual technologies and may require some more contributions. We must never confine our knowledge to the knowledge base of an expert at a given time, but must stay open for new insights. KW - Mach Number KW - Wind Tunnel KW - Supersonic Flow KW - Pitching Moment KW - Wave Drag Y1 - 1997 SN - 3-2118-2815-X U6 - http://dx.doi.org/10.1007/978-3-7091-2658-5_5 SP - 69 EP - 96 PB - Springer CY - Wien [u.a.] ER - TY - CHAP A1 - Mertens, Josef ED - Sobieczky, H. T1 - Certification of supersonic civil transports T2 - New design concepts for high speed air transport. - (Courses and lectures / International Centre for Mechanical Sciences ; 366) N2 - Since certification of Concorde new certification standards were introduced including many new regulations to improve flight safety. Most of these standards are to prevent severe accidents in the future which happened in the past (here: after Concorde’s certification). A new SCT has to fulfill these standards, although Concorde had none of these accidents. But accidents - although they sometimes occurred only for a specific aircraft type - have to be avoided for any (new) aircraft. Because of existing aircraft without typical accident types having demonstrated their reliability, they are allowed to go on based on their old certification; although sometimes new rules prevent accident types which are not connected to specific aircraft types - like e.g. evacuation rules. Anyway, Concorde is allowed to fly based on its old certification, and hopefully in the future will fly as safely as in the past. But a new SCT has to fulfill updated rules like any other aircraft, and it has to be “just another aircraft” [75]. KW - Noise Exposure KW - Evacuation Rule KW - Severe Accident KW - Certification Rule KW - Thermal Fatigue Testing Y1 - 1997 SN - 3-2118-2815-X U6 - http://dx.doi.org/10.1007/978-3-7091-2658-5_6 SP - 97 EP - 103 PB - Springer CY - Wien [u.a.] ER - TY - CHAP A1 - Mertens, Josef ED - Sobieczky, H. T1 - Supersonic laminar flow T2 - New design concepts for high speed air transport. - (Courses and lectures / International Centre for Mechanical Sciences ; 366) N2 - Supersonic transports are very drag sensitive. Technology to reduce drag by application of laminar flow, therefore, will be important; it is a prerequisite to achieve very long range capability. In earlier studies it was assumed that SCTs would only become possible by application of laminar flow [376]. But today, we request an SCT to be viable without application of laminar flow in order to maintain its competitiveness when laminar flow becomes available for subsonic and supersonic transports. By reducing fuel burned, laminar flow drag reduction reduces size and weight of the aircraft, or increases range capability -whereas otherwise size and weight would grow towards infinity. Transition mechanisms from laminar to turbulent state of the boundary layer flow (ALT, CFI, TSI) function as for transonic transports, but at more severe conditions: higher sweep angles, cooled surfaces; higher mode instabilities (HMI) must at least be taken into account, although they may not become important below Mach 3. Hitherto there is a worldwide lack of ground test facilities to investigate TSI at the expected cruise Mach numbers between 1.6 and 2.4; in Stuttgart, Germany one such facility -a Ludwieg tube- is still in the validation phase. A quiet Ludwieg tunnel could be a favourable choice for Europe. But it will require a new approach in designing aircraft which includes improved theoretical predictions, usage of classical wind tunnels for turbulent flow and flight tests for validation. KW - Wind Tunnel KW - Flight Test KW - Supersonic Wind Tunnel KW - Parabolized Stability Equation Y1 - 1997 SN - 3-2118-2815-X U6 - http://dx.doi.org/10.1007/978-3-7091-2658-5_18 SP - 275 EP - 290 PB - Springer CY - Wien [u.a.] ER - TY - CHAP A1 - Mertens, Josef ED - Sobieczky, H. T1 - Son of Concorde, a technology challenge T2 - New design concepts for high speed air transport. - (Courses and lectures / International Centre for Mechanical Sciences ; 366) N2 - Concorde (Figure 9) is the only supersonic airliner which has been introduced into regular passenger service. It is still in service at British Airways and Air France without any flight accidents, and probably will stay in service for at least for ten more years. KW - Technology Challenge KW - Multidisciplinary Design Optimization KW - Specific Fuel Consumption KW - Engine Efficiency KW - Sonic Boom Y1 - 1997 SN - 3-2118-2815-X U6 - http://dx.doi.org/10.1007/978-3-7091-2658-5_3 SP - 31 EP - 51 PB - Springer CY - Wien [u.a.] ER - TY - JOUR A1 - Mertens, Josef T1 - Charakteristiken des Staub-Gas-Gemisches JF - Zeitschrift für angewandte Mathematik und Mechanik : ZAMM. 65 (1985), H. 4 Y1 - 1985 SN - 1521-4001 SP - T211 EP - T213 ER - TY - BOOK A1 - Mertens, Josef T1 - Instationäre Strömungen von Gasen mit brennbaren Partikeln Y1 - 1983 N1 - Aachen, Techn. Hochschule, Diss., 1983 CY - Aachen ER - TY - CHAP A1 - Mertens, Josef T1 - Next steps envisaged to improve wing performance of commercial aircraft T2 - Aerodynamic drag reduction technologies : proceedings of the CEAS/DragNet European Drag Reduction Conference, 19–21 June 2000, Potsdam, Germany. - (Notes on numerical fluid mechanics ; 76) Y1 - 2001 SN - 3-540-41911-X (Print) SN - 978-3-540-45359-8 (Elektronisch) U6 - http://dx.doi.org/10.1007/978-3-540-45359-8_26 SP - 246 EP - 255 PB - Springer CY - Berlin [u.a.] ER - TY - CHAP A1 - Mertens, Josef T1 - Reduction of aerodynamic drag (RaWid)-Status after the first year of the program T2 - New results in numerical and experimental fluid mechanics. - (Notes on numerical fluid mechanics ; 60) N2 - The technology programme “Reduction of aerodynamic drag (RaWid)” for high speed aerodynamics at Daimler-Benz Aerospace Airbus is sponsered by the German ministry for education, research and technology since July 1, 1995. Connected to this industrial programme are the cooperation programmes “MEGAFLOW” under leadership of the DLR and “Transition” by the DFG, and several contributions by DLR and universities. The programme is oriented towards technologies required for a MEGALINER which gains momentum by the ambitious plans for a new large Airbus A3XX. In the first year new technological steps were undertaken in theory, design and experiment. Some critical steps were verified by wing designs checked in wind tunnel tests. KW - Wind Tunnel KW - Aerodynamic Drag KW - Flight Test KW - Friction Drag Y1 - 1997 SN - 3-528-06960-0 U6 - http://dx.doi.org/10.1007/978-3-322-86573-1_2 SP - 7 EP - 14 PB - Vieweg CY - Braunschweig [u.a.] ER - TY - JOUR A1 - Mertens, Josef T1 - Luft hat keine Balken, aber enorme Kräfte : Aerodynamik - die unsichtbare Kraft JF - HEmagazin : das Hocheffizienz-Magazin von Wilo. 2006 (2006), H. 1 Y1 - 2006 SP - 4 EP - 9 PB - - ER - TY - JOUR A1 - Mertens, Josef T1 - Required technologies for supersonic aircraft JF - Fluid dynamics research on supersonic aircraft : this report is a compilation of the edited proceedings of the special course on "Fluid dynamic research on supersonic aircraft" held at the Karman Institute for Fluid Dynamics (VKI) in Rhode-Saint-Genese, Belgium, 25-29 May 1998 Y1 - 1998 SN - 92-837-1007-X N1 - (RTO educational notes ; 4) SP - 5.1 EP - 5.16 PB - Research and Technology Organization CY - Neuilly-sur-Seine ER - TY - JOUR A1 - Mertens, Josef T1 - Multi point design challenges for supersonic transports JF - 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 Y1 - 1998 SN - 92-837-1007-X SP - 8.1 EP - 8.12 PB - Research and Technology Organization CY - Neuilly-sur-Seine ER - TY - JOUR A1 - Mertens, Josef T1 - Laminar flow for supersonic transports JF - Proceedings : March 16 - 18, 1992, Congress Centrum, Hamburg, Federal Republic of Germany / organized jointly by: Deutsche Gesellschaft für Luft- und Raumfahrt e.V. ... [Programme committee J. Szodruch ...] Y1 - 1992 SN - 3-922010-73-3 N1 - DGLR-Bericht ; 92,06 SP - 319 EP - 323 PB - DGLR CY - Bonn ER - TY - JOUR A1 - Mertens, Josef T1 - Aerodynamische Ziele des Adaptiven Flügels (ADIF). JF - DGLR-Jahrbuch 1998 Bd. 1 Y1 - 1998 N1 - DGLR-JT98-213 SP - 47 EP - 52 ER - TY - JOUR A1 - Mertens, Josef T1 - Einige herausragende Ergebnisse des Technologieprogramms "Reduktion des Aerodynamischen Widerstands (RaWid)" JF - DGLR-Jahrbuch 1999 Bd. 3 Y1 - 1999 N1 - DGLR-JT99-047 SP - 1461 EP - 1468 ER - TY - BOOK A1 - Mertens, Josef T1 - Reduktion des aerodynamischen Widerstands (RaWid) : Abschlußbericht ; Laufzeit des Vorhaben, Berichtszeitraum: 01.07.1995 bis 31.12.1998 / Verf.: J. Mertens Y1 - 1999 N1 - Förderkenzeichen BMBF 20 A 9595 A. Engl. Zsfassung u.d.T.: Reduction of aerodynamis drag (RaWid) - final report . auch als elektronisches Dokument vorh. PB - DaimlerChrysler Aerospare Airbus GmbH CY - Hamburg ER - TY - BOOK A1 - Mertens, Josef T1 - Reduktion des aerodynamischen Widerstands (RaWid) : Abschlußbericht ; Laufzeit des Vorhaben, Berichtszeitraum: 01.07.1995 bis 31.12.1998 / Verf.: J. Mertens Y1 - 1999 N1 - Parallel als gedruckte Ausgabe erschienen PB - DaimlerChrysler Aerospare Airbus GmbH CY - Hamburg ER - TY - CHAP A1 - Mertens, Josef ED - Nitsche, Wolfgang T1 - Some important results of the technology programme RaWid T2 - 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) Y1 - 1999 SN - 978-3-663-10903-7 (Print) SN - 978-3-663-10901-3 (Elektronisch) U6 - http://dx.doi.org/10.1007/978-3-663-10901-3_41 SP - 315 EP - 322 PB - Springer Fachmedien CY - Wiesbaden ER - TY - CHAP A1 - Mertens, Josef A1 - Becker, K. ED - Ballmann, Josef T1 - Numerical solution of flow equations : an aircraft designer's view T2 - 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) N2 - 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. Y1 - 1989 SN - 3-528-08098-1 U6 - http://dx.doi.org/10.1007/978-3-322-87869-4_41 N1 - International Conference on Nonlinear Hyperbolic Problems <3, 1988, Aachen> SP - 403 EP - 412 PB - Vieweg CY - Braunschweig ER - TY - JOUR A1 - Mertens, Josef A1 - Henke, Rolf T1 - Adaptive technologies for future civil air transport JF - Air & Space Europe. 3 (2001), H. 3-4 Y1 - 2001 SN - 1247-5793 SP - 80 EP - 82 ER - TY - JOUR A1 - Mertens, Josef A1 - Hünecke, Klaus T1 - Experimentelle Untersuchung zur Landeeigenschaft von Hyperschall-Fluggeräten / Hünecke, Klaus ; Mertens, Josef JF - DGLR-Jahrbuch 1988 Bd. 1 Y1 - 1988 N1 - DGLR-88-123 SP - 706 ER - TY - JOUR A1 - Mertens, Josef A1 - Kelm, R. A1 - Velden, A. van der T1 - Interdisziplinäre Auslegung eines Verkehrsflugzeugflügels JF - DGLR-Jahrbuch 1999 Bd. 3 Y1 - 1999 N1 - DGLR-JT99-156 SP - 1605 EP - 1610 ER - TY - JOUR A1 - Mertens, Josef A1 - Klevenhusen, K. D. A1 - Jakob, H. T1 - Accurate Transonic Wave Drag Prediction Using Simple Physical Models JF - AIAA-Journal. 25 (1987), H. 6 Y1 - 1987 SN - 0001-1452 SP - 799 EP - 805 ER - TY - PAT A1 - Mertens, Josef A1 - Lajain, Henri T1 - Method of fabricating leading edge nose structures of aerodynamic surfaces : patent no.: US 6,415,510 B2 ; date of patent: Jul. 9, 2002 Y1 - 2002 N1 - Volltext auch in der Datenbank http://publikationen.dpma.de/ zu finden unter der Nummer US000006415510B2 PB - United States Patent and Trademark Office CY - [Washington, DC] ER - TY - JOUR A1 - Mertens, Josef A1 - Röger, Wolf T1 - F-Schlepp: Problem Taumelschwingung JF - Aerokurier. 44 (2000), H. 10 Y1 - 2000 SN - 0341-1281 N1 - in der Bereichsbibliothek unter der Signatur 23 Z 391-2000 SP - 73 EP - 73 ER - TY - PAT A1 - Mertens, Josef A1 - Velden, Alexander van der A1 - Kelm, Roland T1 - Flugzeug mit Flügeln, deren maximaler Auftrieb durch steuerbare Flügelkomponenten veränderbar ist : Offenlegungsschrift DE102004045732 ; Offenlegungstag: 30.03.2006 = Aircraft with wings whose maximum lift can be altered by controllable wing components Y1 - 2006 N1 - Zugleich EP1791755A1. - Volltext über Datenbank: http://publikationen.dpma.de/ PB - Deutsches Patent- und Markenamt CY - München ER - TY - BOOK A1 - Mertens, Josef A1 - Velden, Alexander van der A1 - Kelm, Roland A1 - Kokan, David T1 - Application of MDO to large subsonic transport aircraft Y1 - 2000 N1 - Aerospace Sciences Meeting and Exhibit <38, 2000, Reno, NV> ; (AIAA Paper ; 00-0844) PB - American Institute of Aeronautics and Astronautics CY - Reston, Va. ER - TY - JOUR A1 - Meyer, Max-Arno A1 - Granrath, Christian A1 - Feyerl, Günter A1 - Richenhagen, Johannes A1 - Kaths, Jakob A1 - Andert, Jakob T1 - Closed-loop platoon simulation with cooperative intelligent transportation systems based on vehicle-to-X communication JF - Simulation Modelling Practice and Theory Y1 - 2021 U6 - http://dx.doi.org/10.1016/j.simpat.2020.102173 SN - 1569-190X VL - 106 IS - Art. 102173 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Möhren, Felix A1 - Bergmann, Ole A1 - Janser, Frank A1 - Braun, Carsten T1 - On the determination of harmonic propeller loads T2 - AIAA SCITECH 2023 Forum N2 - 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. Y1 - 2023 U6 - http://dx.doi.org/10.2514/6.2023-2404 N1 - AIAA SCITECH 2023 Forum, 23-27 January 2023, National Harbor, MD & Online PB - AIAA ER - TY - JOUR A1 - Möhren, Felix A1 - Bergmann, Ole A1 - Janser, Frank A1 - Braun, Carsten T1 - On the influence of elasticity on propeller performance: a parametric study JF - CEAS Aeronautical Journal N2 - 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. KW - Propeller KW - Finite element method KW - Blade element method KW - Propeller elasticity KW - Aeroelasticity Y1 - 2023 U6 - http://dx.doi.org/10.1007/s13272-023-00649-y SN - 1869-5590 (Online) SN - 1869-5582 (Print) N1 - Corresponding author: Felix Möhren VL - 14 SP - 311 EP - 323 PB - Springer Nature CY - Berlin 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 - Neu, Eugen A1 - Janser, Frank A1 - Khatibi, Akbar A. A1 - Orifici, Adrian C. T1 - Operational modal analysis of a cantilever in a wind tunnel using optical fiber bragg grating sensors T2 - 6th International Operational Modal Analysis Conference. IOMAC´15. 2015 May 12-14 Gijon - Spain Y1 - 2015 U6 - http://dx.doi.org/10.13140/RG.2.1.3753.0324 ER - TY - JOUR A1 - Neu, Eugen A1 - Janser, Frank A1 - Khatibi, Akbar A. A1 - Orifici, Adrian C. T1 - Fully Automated Operational Modal Analysis using multi-stage clustering JF - Mechanical Systems and Signal Processing Y1 - 2017 U6 - http://dx.doi.org/10.1016/j.ymssp.2016.07.031 SN - 0888-3270 VL - Vol. 84, Part A SP - 308 EP - 323 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Neu, Eugen A1 - Janser, Frank A1 - Khatibi, Akbar A. A1 - Orifici, Adrian C. T1 - Automated modal parameter-based anomaly detection under varying wind excitation JF - Structural Health Monitoring N2 - Wind-induced operational variability is one of the major challenges for structural health monitoring of slender engineering structures like aircraft wings or wind turbine blades. Damage sensitive features often show an even bigger sensitivity to operational variability. In this study a composite cantilever was subjected to multiple mass configurations, velocities and angles of attack in a controlled wind tunnel environment. A small-scale impact damage was introduced to the specimen and the structural response measurements were repeated. The proposed damage detection methodology is based on automated operational modal analysis. A novel baseline preparation procedure is described that reduces the amount of user interaction to the provision of a single consistency threshold. The procedure starts with an indeterminate number of operational modal analysis identifications from a large number of datasets and returns a complete baseline matrix of natural frequencies and damping ratios that is suitable for subsequent anomaly detection. Mahalanobis distance-based anomaly detection is then applied to successfully detect the damage under varying severities of operational variability and with various degrees of knowledge about the present operational conditions. The damage detection capabilities of the proposed methodology were found to be excellent under varying velocities and angles of attack. Damage detection was less successful under joint mass and wind variability but could be significantly improved through the provision of the currently encountered operational conditions. Y1 - 2016 U6 - http://dx.doi.org/10.1177/1475921716665803 SN - 1475-9217 VL - 15 IS - 6 SP - 1 EP - 20 PB - Sage CY - London ER - TY - CHAP A1 - Neu, Eugen A1 - Janser, Frank A1 - Khatibi, Akbar A. A1 - Orifici, Adrian C. T1 - In-flight vibration-based structural health monitoring of aircraft wings T2 - 30th Congress of the internatonal council of the aeronautical sciences : 25.-30. September 2016, Daejeon, Korea N2 - This work presents a methodology for automated damage-sensitive feature extraction and anomaly detection under multivariate operational variability for in-flight assessment of wings. The method uses a passive excitation approach, i. e. without the need for artificial actuation. The modal system properties (natural frequencies and damping ratios) are used as damage-sensitive features. Special emphasis is placed on the use of Fiber Bragg Grating (FBG) sensing technology and the consideration of Operational and Environmental Variability (OEV). Measurements from a wind tunnel investigation with a composite cantilever equipped with FBG and piezoelectric sensors are used to successfully detect an impact damage. In addition, the feasibility of damage localisation and severity estimation is evaluated based on the coupling found between damageand OEV-induced feature changes. Y1 - 2016 ER - TY - CHAP A1 - Niedermeier, H. A1 - Clemens, J. A1 - Kowalski, Julia A1 - Macht, S. A1 - Heinen, D. A1 - Hoffmann, R. A1 - Linder, Peter T1 - Navigation system for a research ice probe for antarctic glaciers T2 - IEEE/ION Position, Location and Navigation Symposium (PLANS) ; 5-8 May 2014, Monterey, Calif. Y1 - 2014 SN - 978-1-4799-3319-8 SP - 959 EP - 975 PB - IEEE CY - Piscataway, NJ ER - TY - PAT A1 - Nonhoff, Gottfried A1 - Wahle, Michael T1 - Anordnung zur Dämpfung von Schwingungen an Bauwerken und Bauteilen : Offenlegungsschrift / Europäische Patentschrift T1 - Arrangement for damping vibrations of structures or parts thereof : patent of invention Y1 - 1990 PB - Deutsches Patent- und Markenamt / Europäisches Patentamt CY - München / Den Hague ER - TY - CHAP A1 - Nowack, N. A1 - Röth, Thilo A1 - Bührig-Polaczek, A. A1 - Klaus, G. ED - Hirsch, Jürgen T1 - Advanced Sheet Metal Components Reinforced by Light Metal Cast Structures T2 - Aluminium alloys : their physical and mechanical properties ; [proceedings of the 11th International Conference on Aluminium Alloys, 22 - 26 Sept. 2008, Aachen, Germany ; ICAA 11] Y1 - 2008 SN - 978-3-527-32367-8 IS - 2 SP - 2374 EP - 2381 ER - TY - CHAP A1 - Ohndorf, Andreas A1 - Dachwald, Bernd A1 - Seboldt, Wolfgang A1 - Schartner, Karl-Heinz T1 - Flight times to the heliopause using a combination of solar and radioisotope electric propulsion T2 - 32nd International Electric Propulsion Conference N2 - We investigate the interplanetary flight of a low-thrust space probe to the heliopause,located at a distance of about 200 AU from the Sun. Our goal was to reach this distance within the 25 years postulated by ESA for such a mission (which is less ambitious than the 15-year goal set by NASA). Contrary to solar sail concepts and combinations of allistic and electrically propelled flight legs, we have investigated whether the set flight time limit could also be kept with a combination of solar-electric propulsion and a second, RTG-powered upper stage. The used ion engine type was the RIT-22 for the first stage and the RIT-10 for the second stage. Trajectory optimization was carried out with the low-thrust optimization program InTrance, which implements the method of Evolutionary Neurocontrol,using Artificial Neural Networks for spacecraft steering and Evolutionary Algorithms to optimize the Neural Networks’ parameter set. Based on a parameter space study, in which the number of thrust units, the unit’s specific impulse, and the relative size of the solar power generator were varied, we have chosen one configuration as reference. The transfer time of this reference configuration was 29.6 years and the fastest one, which is technically more challenging, still required 28.3 years. As all flight times of this parameter study were longer than 25 years, we further shortened the transfer time by applying a launcher-provided hyperbolic excess energy up to 49 km2/s2. The resulting minimal flight time for the reference configuration was then 27.8 years. The following, more precise optimization to a launch with the European Ariane 5 ECA rocket reduced the transfer time to 27.5 years. This is the fastest mission design of our study that is flexible enough to allow a launch every year. The inclusion of a fly-by at Jupiter finally resulted in a flight time of 23.8 years,which is below the set transfer-time limit. However, compared to the 27.5-year transfer,this mission design has a significantly reduced launch window and mission flexibility if the escape direction is restricted to the heliosphere’s “nose". KW - low-thrust trajectory optimization KW - heliosphere KW - ion propulsion Y1 - 2011 N1 - IEPC-2011-051 32nd International Electric Propulsion Conference,September 11–15, 2011 Wiesbaden, Germany SP - 1 EP - 12 ER - TY - JOUR A1 - Olaru, Alexandra Maria A1 - Kowalski, Julia A1 - Sethi, Vaishali A1 - Blümich, Bernhard T1 - Exchange relaxometry of flow at small Péclet numbers in a glass bead pack JF - Journal of Magnetic Resonance (JMR) N2 - In this paper we consider low Péclet number flow in bead packs. A series of relaxation exchange experiments has been conducted and evaluated by ILT analysis. In the resulting correlation maps, we observed a collapse of the signal and a translation towards smaller relaxation times with increasing flow rates, as well as a signal tilt with respect to the diagonal. In the discussion of the phenomena we present a mathematical theory for relaxation exchange experiments that considers both diffusive and advective transport. We perform simulations based on this theory and discuss them with respect to the conducted experiments. KW - NMR exchange relaxometry KW - Low-field NMR Y1 - 2012 U6 - http://dx.doi.org/10.1016/j.jmr.2012.04.015 SN - 1096-0856 VL - 220 SP - 32 EP - 44 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Olaru, Alexandra Maria A1 - Kowalski, Julia A1 - Sethi, Vaishali A1 - Blümich, Bernhard T1 - Fluid Transport in Porous Media probed by Relaxation-Exchange NMR T2 - 2011 Fall Meeting, AGU, San Francisco, Calif., 5-9 Dec. Y1 - 2011 N1 - H12B-07; American Geophysical Union ER - TY - CHAP A1 - Otten, D. A1 - Schmid, M. A1 - Weber, Tobias T1 - Advances In Sheet Metal-Forming: Reduction Of Tooling Cost By Methodical Optimization T2 - Proceedings of SAMPE Europe Conference, Amiens , France Y1 - 2015 ER - TY - CHAP A1 - Otten, D. A1 - Schmidt, M. A1 - Weber, Tobias T1 - Advances in Determination of Material Parameters for Functional Simulations Based on Process Simulations T2 - SAMPE Europe Conference 16 Liege Y1 - 2016 SN - 978-1-5108-3800-0 SP - 570 EP - 577 ER - TY - JOUR A1 - Otten, Dennis A1 - Weber, Tobias A1 - Arent, Jan-Christoph T1 - Manufacturing Process Simulation – On Its Way to Industrial Application JF - International Journal of Aviation, Aeronautics, and Aerospace N2 - Manufacturing process simulation (MPS) has become more and more important for aviation and the automobile industry. A highly competitive market requires the use of high performance metals and composite materials in combination with reduced manufacturing cost and time as well as a minimization of the time to market for a new product. However, the use of such materials is expensive and requires sophisticated manufacturing processes. An experience based process and tooling design followed by a lengthy trial-and-error optimization is just not contemporary anymore. Instead, a tooling design process aided by simulation is used more often. This paper provides an overview of the capabilities of MPS in the fields of sheet metal forming and prepreg autoclave manufacturing of composite parts summarizing the resulting benefits for tooling design and manufacturing engineering. The simulation technology is explained briefly in order to show several simplification and optimization techniques for developing industrialized simulation approaches. Small case studies provide examples of an efficient application on an industrial scale. Y1 - 2018 U6 - http://dx.doi.org/10.15394/ijaaa.2018.1217 SN - 2374-6793 VL - 5 IS - 2 PB - Embry-Riddle Aeronautical University CY - Daytona Beach, Fla. ER - TY - JOUR A1 - Overduin, James A1 - Blome, Hans-Joachim A1 - Hoell, Josef T1 - Wolfgang Priester: from the big bounce to the Lambda-dominated universe JF - Naturwissenschaften Y1 - 2007 SN - 0028-1042 VL - 94 IS - 6 SP - 417 EP - 429 ER - TY - CHAP A1 - Pasligh, N. A1 - Funke, D. A1 - Röth, Thilo A1 - Krack, R. T1 - Leichtbau Quertrager als Stahlblech-Aluminiumdruckguss-Hybrid - Von der numerischen Berechnung bis zum realen Prototypen T2 - VDI BERICHTE Y1 - 2010 SN - 978-3-18-092107-5 N1 - 15. Kongress SIMVEC Berechnung und Simulation im Fahrzeugbau, Baden-Baden, 16. und 17. November 2010 PB - VDI Verlag CY - Düsseldorf ER - TY - JOUR A1 - Peeken, Heinz A1 - Rosenkranz, Josef A1 - Schelenz, R. T1 - Berücksichtigung des Einflusses der Gleitlagergehäusesteifigkeit auf das dynamische Verhalten von Rotoren JF - Antriebstechnik : Organ der Forschungsvereinigung Antriebstechnik e.V. Y1 - 1991 SN - 0341-2652 VL - 30 IS - 9 SP - 71 EP - 75 ER - TY - CHAP A1 - Peeken, Heinz A1 - Troeder, Christoph A1 - Schmidt, J. A1 - Rosenkranz, Josef T1 - Principles of machine noise reduction T2 - Inter-noise 85 : proceedings ; 1985 international conference on noise control engineering ; Munich, Sept. 18 - 20, 1985. - (Schriftenreihe der Bundesanstalt für Arbeitsschutz : Tagungsbericht ; 39) Y1 - 1985 SN - 3-88314-417-7 SP - 23 EP - 36 PB - Bundesanstalt für Arbeitsschutz [u.a.] CY - Dortmund [u.a.] ER - TY - CHAP A1 - Peloni, A. A1 - Ceriotti, M. A1 - Dachwald, Bernd T1 - Preliminary trajectory design of a multiple NEO rendezvous mission through solar sailing T2 - Proceedings of the International Astronautical Congress, IAC, Vol. 8, 2014 Y1 - 2015 SN - 978-1-63439-986-9 SP - 5352 EP - 5366 PB - Curran CY - Red Hook, NY ER - TY - CHAP A1 - Peloni, Alessandro A1 - Ceriotti, Matteo A1 - Dachwald, Bernd T1 - Solar-Sailing Trajectory Design for Close-up NEA Observations Mission T2 - 4th IAA Planetary Defense Conference - PDC 2015, 13-17 April 2015, Frascati, Roma, Italy Y1 - 2015 N1 - IAA-PDC-15-P-19 ER - TY - JOUR A1 - Peloni, Alessandro A1 - Ceriotti, Matteo A1 - Dachwald, Bernd T1 - Solar-sail trajectory design for a multiple near-earth-asteroid rendezvous mission JF - Journal of Guidance, Control, and Dynamics N2 - The scientific interest for near-Earth asteroids as well as the interest in potentially hazardous asteroids from the perspective of planetary defense led the space community to focus on near-Earth asteroid mission studies. A multiple near-Earth asteroid rendezvous mission with close-up observations of several objects can help to improve the characterization of these asteroids. This work explores the design of a solar-sail spacecraft for such a mission, focusing on the search of possible sequences of encounters and the trajectory optimization. This is done in two sequential steps: a sequence search by means of a simplified trajectory model and a set of heuristic rules based on astrodynamics, and a subsequent optimization phase. A shape-based approach for solar sailing has been developed and is used for the first phase. The effectiveness of the proposed approach is demonstrated through a fully optimized multiple near-Earth asteroid rendezvous mission. The results show that it is possible to visit five near-Earth asteroids within 10 years with near-term solar-sail technology. Y1 - 2016 U6 - http://dx.doi.org/10.2514/1.G000470 SN - 0731-5090 VL - 39 IS - 12 SP - 2712 EP - 2724 PB - AIAA CY - Reston, Va. ER - TY - JOUR A1 - Peloni, Alessandro A1 - Dachwald, Bernd A1 - Ceriotti, Matteo T1 - Multiple near-earth asteroid rendezvous mission: Solar-sailing options JF - Advances in Space Research Y1 - 2017 U6 - http://dx.doi.org/10.1016/j.asr.2017.10.017 SN - 0273-1177 IS - In Press, Corrected Proof PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Peloni, Alessandro A1 - Dachwald, Bernd A1 - Ceriotti, Matteo T1 - Multiple NEA rendezvous mission: Solar sailing options T2 - Fourth International Symposium on Solar Sailing N2 - The scientific interest in near-Earth asteroids (NEAs) and the classification of some of those as potentially hazardous asteroid for the Earth stipulated the interest in NEA exploration. Close-up observations of these objects will increase drastically our knowledge about the overall NEA population. For this reason, a multiple NEA rendezvous mission through solar sailing is investigated, taking advantage of the propellantless nature of this groundbreaking propulsion technology. Considering a spacecraft based on the DLR/ESA Gossamer technology, this work focuses on the search of possible sequences of NEA encounters. The effectiveness of this approach is demonstrated through a number of fully-optimized trajectories. The results show that it is possible to visit five NEAs within 10 years with near-term solar-sail technology. Moreover, a study on a reduced NEA database demonstrates the reliability of the approach used, showing that 58% of the sequences found with an approximated trajectory model can be converted into real solar-sail trajectories. Lastly, this second study shows the effectiveness of the proposed automatic optimization algorithm, which is able to find solutions for a large number of mission scenarios without any input required from the user. KW - Multiphase KW - Trajectory Optimization KW - Automated Optimization KW - Gossamer KW - Sequence-Search Y1 - 2017 N1 - Fourth International Symposium on Solar Sailing (ISSS 2017), Kyoto, Japan, 17-20 Jan 2017. http://www.jsforum.or.jp/ISSS2017/ SP - 1 EP - 11 ER - TY - JOUR A1 - Peterson, Leif Arne A1 - Röth, Thilo A1 - Uibel, Thomas T1 - Einsatz von Holzwerkstoffen in Fahrzeugstrukturen JF - Bauen mit Holz Y1 - 2017 SN - 0005-6545 N1 - gedruckt in der Bereichsbibliothek Bayernallee IS - 3 SP - 32 EP - 38 PB - Bruderverlag CY - Köln ER - TY - CHAP A1 - Peterson, Leif Arne A1 - Röth, Thilo A1 - Uibel, Thomas ED - Uibel, Thormas ED - Peterson, Leif Arne ED - Baumann, Marcus T1 - Holzwerkstoffe in Karosseriestrukturen T2 - Tagungsband Aachener Holzbautagung 2017 Y1 - 2017 SN - 2197-4489 SP - 34 EP - 45 ER - TY - CHAP A1 - Pflug, J. A1 - Wahle, Michael ED - Bürger, Gudrun T1 - Auslegung der CFK-Sandwich-Rumpfstruktur eines Hubschraubers mit der Methode der Finiten Elemente T2 - Basistechnologien für neue Herausforderungen in der Luft- und Raumfahrt : DGLR-Jahrestagung / Deutscher Luft- und Raumfahrt-Kongress 1994, Erlangen, 04.- 07. Oktober 1994. - (Jahrbuch der Deutschen Gesellschaft für Luft- und Raumfahrt ; 1994,3) Y1 - 1994 SP - 1135 EP - 1144 PB - DGLR CY - Bonn ER - TY - JOUR A1 - Pichler, A. A1 - George, A. A1 - Seiler, F. A1 - Srulijes, J. A1 - Havermann, Marc T1 - Doppler Picture Velocimetry (DPV) applied to hypersonics JF - Shock Waves [Elektronische Ressource] : 26th International Symposium on Shock Waves, Volume 1 / edited by Klaus Hannemann, Friedrich Seiler Y1 - 2009 SN - 978-3-540-85168-4 N1 - International Symposium on Shock Waves ; (26 ; 2007.07.15-20 ; Göttingen) ; ISSW ; (26 ; 2007.07.15-20 ; Göttingen) SP - 503 EP - 508 PB - Springer CY - Berlin ER - TY - CHAP A1 - Pielen, Michael A1 - Röth, Thilo A1 - Flatten, T. ED - Proff, H. T1 - Erfolgsfaktoren künftiger Geschäftsmodelle von urbanen, geteilten Mobilitätsdienstleistungen T2 - Mobilität und digitale Transformation. (9. Wissenschaftsforum Mobilität. Tagungsband) N2 - Digitalisierung bezeichnet die Nutzung großer Datenmengen, die zu einer umfassenden Vernetzung aller Bereiche der Wirtschaft und Gesellschaft führen wird (BMWi, 2015 und ähnlich Köhler/Wollschläger, 2014: 79). Sie umfasst die Erhebung von analogen Informationen („Big Data“ in einem engen Sinne; z.B. O´Leary, 2013), ihre Speicherung in einem digitaltechnischen System (lokale Speicherung oder „Cloud Computing“ durch die Weiterentwickelung des Internets; z.B. Hashem et al., 2015: 101), die Analyse und Interpretation sowie den Transfer in andere Systeme („Internet der Dinge“ bzw. „Internet of Things“; z.B. Ashton, 2009). Y1 - 2018 SN - 978-3-658-20779-3 U6 - http://dx.doi.org/10.1007/978-3-658-20779-3_2 SP - 435 EP - 448 PB - Springer Gabler CY - Wiesbaden ER - TY - CHAP A1 - Pirovano, Laura A1 - Seefeldt, Patric A1 - Dachwald, Bernd A1 - Noomen, Ron T1 - Attitude and Orbital Dynamics Modeling for an Uncontrolled Solar-Sail Experiment in Low-Earth Orbit T2 - 25th International Symposium on Spaceflight Dynamics, 2015, Munich, Germany Y1 - 2015 ER - TY - CHAP A1 - Pirovano, Laura A1 - Seefeldt, Patric A1 - Dachwald, Bernd A1 - Noomen, Ron T1 - Attitude and orbital modeling of an uncontrolled solar-sail experiment in low-Earth orbit T2 - 25th International Symposium on Space Flight Dynamics ISSFD N2 - Gossamer-1 is the first project of the three-step Gossamer roadmap, the purpose of which is to develop, prove and demonstrate that solar-sail technology is a safe and reliable propulsion technique for long-lasting and high-energy missions. This paper firstly presents the structural analysis performed on the sail to understand its elastic behavior. The results are then used in attitude and orbital simulations. The model considers the main forces and torques that a satellite experiences in low-Earth orbit coupled with the sail deformation. Doing the simulations for varying initial conditions in attitude and rotation rate, the results show initial states to avoid and maximum rotation rates reached for correct and faulty deployment of the sail. Lastly comparisons with the classic flat sail model are carried out to test the hypothesis that the elastic behavior does play a role in the attitude and orbital behavior of the sail KW - Solar sail KW - Gossamer structures KW - Attitude dynamics KW - Orbital dynamics Y1 - 2015 N1 - 25th International Symposium on Space Flight Dynamics ISSFD October 19 – 23, 2015, Munich, Germany https://issfd.org/2015/ SP - 1 EP - 15 ER - TY - PAT A1 - Pischinger, Martin A1 - Esch, Thomas A1 - Duesmann, Klaus T1 - Elektromagnetischer Aktuator mit gelenkig abgestützter Rückstellfeder N2 - Die Erfindung betrifft einen elektromagnetischen Aktuator zur Betätigung eines Stellgliedes (7) mit wenigstens einem gesteuert bestrombaren Elektromagneten (1, 2) und einem mit dem Stellglied (7) in Wirkverbindung stehenden Anker (5), der bei Bestromung des Elektromagneten (1, 2) gegen die Kraft wenigstens einer an einem Gehäuse (12) abgestützten Rückstellfeder (10) an der Polfläche (3, 4) des Elektromagneten (1, 2) zur Anlage kommt, und daß zumindest der Anker (5) über eine sphärische Gelenkanordnung (11) auf der Rückstellfeder (10) abgestützt ist. Y1 - 2023 N1 - Patent DE000019822907B4 2006.07.27 ER - TY - CHAP A1 - Plescher, Engelbert A1 - Mathiak, Gerhard A1 - Willnecker, Rainer T1 - Technical aspects of liquid diffusion model experiments T2 - 55th International Astronautical Congress : October 4 - 8, 2004, Vancouver, Canada / International Astronautical Federation. Bd. 8. IAC-04-J.5.04 Y1 - 2005 SP - 5019 EP - 5025 PB - International Astronautical Federation CY - Paris ER - TY - GEN A1 - Polaczek, Christa T1 - Kofaser - Kategorien und differentielle Algebren Y1 - 1983 N1 - Bonn, Univ., Diplomarb., 1983 PB - Math. Inst. der Univ. CY - Bonn ER - TY - THES A1 - Polaczek, Christa T1 - Automatische 3-dimensionale FEM-Netzgenerierung für die Formfüll- und Erstarrungssimulation. - (Fortschrittberichte VDI : Reihe 20, Rechnerunterstützte Verfahren ; 182) Y1 - 1995 SN - 3-18-318220-3 N1 - Zugl.: Aachen, Techn. Hochsch., Diss., 1994 IS - Als Ms. gedr. PB - VDI-Verl. CY - Düsseldorf ER - TY - JOUR A1 - Polaczek, Christa A1 - Henn, Gudrun T1 - Gute Vorkenntnisse verkürzen die Studienzeit JF - Mathematikinformation : eine Zeitschrift von Begabtenförderung Mathematik e.V. Y1 - 2008 SN - 1612-9156 VL - 2008 IS - 49 SP - 46 EP - 50 PB - Begabtenförderung Mathematik CY - Neubiberg ER - TY - CHAP A1 - Quitter, Julius A1 - Marino, Matthew A1 - Bauschat, J.-Michael T1 - Highly Non-Planar Aircraft Configurations: Estimation of Flight Mechanical Derivatives Using Low-Order Methods T2 - Deutscher Luft- und Raumfahrtkongress 2019, DLRK 2019. Darmstadt, Germany Y1 - 2019 ER - TY - PAT A1 - Rainer, Nähle A1 - Röstel, Reinhard A1 - Wahle, Michael T1 - Lagerungssystem in einem Raumfahrzeug : Patentschrift T1 - Storage system for use inside a spacecraft has damping elements consisting of at least one permanent magnet and vortex flow plate : patent of invention Y1 - 2006 PB - Deutsches Patent- und Markenamt CY - München ER - TY - JOUR A1 - Recker, Elmar A1 - Bosschaerts, Walter A1 - Wagemakers, Rolf A1 - Hendrick, Patrick A1 - Funke, Harald A1 - Börner, Sebastian T1 - Experimental study of a round jet in cross-flow at low momentum ratio JF - 15th International Symposium on Applications of Laser Techniques to Fluid Mechanics Lisbon, Portugal, 05-08 July, 2010 - 1 Y1 - 2010 SP - 1 EP - 13 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 - TY - CHAP A1 - Reimer, Lars A1 - Braun, Carsten A1 - Ballmann, Josef T1 - Analysis of the static and dynamic aero-structural response of an elastic swept wing model by direct aeroelastic simulation 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. 2006-10.3.3 PB - Optimage CY - Edinburgh 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 - 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 - 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 - CHAP A1 - Rings, René A1 - Ludowicy, Jonas A1 - Finger, Felix A1 - Braun, Carsten A1 - Bil, Cees T1 - Sensitivity Analysis of General Aviation Aircraft with Parallel Hybrid-Electric Propulsion Systems T2 - Asia Pacific International Symposium on Aerospace Technology. APISAT 2019 Y1 - 2019 ER - TY - JOUR A1 - Robinson, A. E. A1 - Funke, Harald A1 - Hendrick, P. T1 - Design and Testing of a Micromix Combustor With Recuperative Wall Cooling for a Hydrogen Fueled µ-Scale Gas Turbine JF - Journal of engineering for gas turbines and power Y1 - 2011 SN - 1528-8919 VL - 133 IS - 8 PB - ASME CY - New York ER - TY - JOUR A1 - Robinson, A. E. A1 - Funke, Harald A1 - Hendrick, P. A1 - Recker, E. A1 - Peirs, J. T1 - Development of a hydrogen fuelled 1 kW ultra micro gas turbine with special respect to designing, testing and mapping of the µ-scale combustor JF - IEEE International Conference on Sustainable Energy Technologies, 2008 : ICSET 2008 ; Singapore, 24 - 27 Nov. 2008. Y1 - 2008 SN - 978-1-4244-1887-9 SP - 656 EP - 660 PB - IEEE CY - Piscataway, NJ ER - TY - JOUR A1 - Robinson, A. E. A1 - Funke, Harald A1 - Wagemakers, R. A1 - Grossen, J. A1 - Bosschaerts, W. A1 - Hendrick, P. T1 - Numerical and Experimental Investigation of a Micromix Combustor for a Hydrogen Fuelled μ-Scale Gas Turbine JF - Proceedings of the ASME Turbo Expo 2009 : : presented at the 2009 ASME Turbo Expo, June 8 - 12, 2009, Orlando, Florida, USA / sponsored by the International Gas Turbine Institute Y1 - 2009 SN - 9780791848869 N1 - GT2009-60061 SP - 253 EP - 262 PB - ASME CY - New York, NY ER - TY - JOUR A1 - Robinson, A. E. A1 - Rönna, Uwe A1 - Funke, Harald T1 - Testing of a 10 kW diffusive micro-mix combustor for hydrogen-fuelled micro-scale gas turbines JF - International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications <7, 2007, Freiburg, Breisgau> ; PowerMEMS ; 7 Y1 - 2007 SP - 225 EP - 228 ER - TY - CHAP A1 - Roosen, Petra A1 - Feyerl, Günter T1 - Gender-specific perception and utilization of personal use vehicles T2 - FISITA World Automotive Congress 2014 : Maastricht, The Netherlands, 2 - 6 June / [organised by the International Federation of Automotive Engineering Societies (FISITA) ...]. Bd. 1 Y1 - 2015 SN - 978-1-5108-0209-4 SP - 418 EP - 425 PB - Curran CY - Red Hook, NY ER - TY - PAT A1 - Rosenkranz, Josef T1 - Überwachungsvorrichtung für eine Auswuchtmaschine : Patentschrift Y1 - 2001 PB - Deutsches Patent- und Markenamt CY - München ER -