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 - Dachwald, Bernd A1 - McDonald, Malcolm A1 - McInnes, Colin R. A1 - Mengali, Giovanni T1 - Impact of Optical Degradation on Solar Sail Mission Performance JF - Journal of Spacecraft and Rockets. 44 (2007), H. 4 Y1 - 2007 SN - 0022-4650 N1 - 2. ISSN: 1533-6794 SP - 740 EP - 749 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Wi, Bong T1 - Solar Sail Kinetic Energy Impactor Trajectory Optimization for an Asteroid-Deflection Mission JF - Journal of Spacecraft and Rockets. 44 (2007), H. 4 Y1 - 2007 SN - 0022-4650 N1 - 2. ISSN: 1533-6794 SP - 755 EP - 764 ER - TY - JOUR A1 - Dachwald, Bernd T1 - Minimum Transfer Times for Nonperfectly Reflecting Solar Sailcraft JF - Journal of Spacecraft and Rockets. 41 (2004), H. 4 Y1 - 2004 SN - 0022-4650 N1 - 2. ISSN: 1533-6794 SP - 693 EP - 695 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Mengali, Giovanni A1 - Quarta, Alessandrao A. A1 - Macdonald, Malcolm T1 - Parametric Model and Optimal Control of Solar Sails with Optical Degradation JF - Journal of guidance, control, and dynamics. 29 (2006), H. 5 Y1 - 2006 SN - 0162-3192 N1 - 2. ISSN: 0731-5090 SP - 1170 EP - 1178 ER - TY - JOUR A1 - Dachwald, Bernd T1 - Optimal Solar Sail Trajectories for Missions to the Outer Solar System JF - Journal of guidance, control, and dynamics. 28 (2005), H. 6 Y1 - 2005 SN - 0162-3192 N1 - 2. ISSN: 0162-3192. - 3. ISSN: 0731-5090 SP - 1187 EP - 1193 ER - TY - JOUR A1 - Dachwald, Bernd T1 - Optimization of Interplanetary Solar Sailcraft Trajectories Using Evolutionary Neurocontrol JF - Journal of guidance, control, and dynamics. 27 (2004), H. 1 Y1 - 2004 SN - 0162-3192 N1 - 2. ISSN: 0162-3192. - 3. ISSN: 0731-5090 SP - 66 EP - 72 ER - TY - JOUR A1 - Dachwald, Bernd T1 - Entwicklung sicherer und wartbarer Software für den Eurofighter JF - Soldat und Technik : Strategie und Technik, Sicherheit (1996) Y1 - 1996 SN - 0038-0989 SP - 663 EP - 668 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Ohndorf, A. A1 - Gill, E. T1 - Optimization of low-thrust Earth-Moon transfers using evolutionary neurocontrol / Ohndorf, A. ; Dachwald, B. ; Gill, E. JF - IEEE Congress on Evolutionary Computation, 2009. CEC '09. Y1 - 2009 SN - 978-1-4244-2958-5 SP - 358 EP - 364 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 - JOUR A1 - Dahmann, Peter A1 - Hagemeister, Wilhelm A1 - Nagel, Günther A1 - Exner, Peter T1 - Geregelte Innenzahnradpumpe im Mehrquadrantenbetrieb Geschwindigkeits- und Positionsregelung eines hydraulischen Handlinggerätes JF - O+P Ölhydraulik und Pneumatik. 24 (2006), H. 1 Y1 - 2006 SN - 0341-2660 SP - 24 EP - 28 ER - TY - JOUR A1 - Trilla, Joan A1 - Grossen, Jürgen A1 - Robinson, Alexander A1 - Funke, Harald A1 - Bosschaerts, Walter A1 - Hendrick, Patrick T1 - Development of a hydrogen combustion chamber for an ultra micro gas turbine JF - PowerMEMS 2008, 8th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications, microEMS 2008, 2nd Symposium on Micro Environmental Machine Systems, Sendai, JP, Nov 9-12, 2008 Y1 - 2008 SP - 101 EP - 104 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 - Blome, Hans-Joachim A1 - Chicone, Carmen A1 - Hehl, Friedrich W. A1 - Mashhoon, Bahram T1 - Nonlocal modification of Newtonian gravity JF - Physical Review D Y1 - 2010 SN - 0556-2821 N1 - 11 pages VL - 81 IS - 6 SP - 065020 ER - TY - JOUR A1 - Wilson, T. L. A1 - Blome, Hans-Joachim T1 - The Pioneer anomaly and a rotating Gödel universe JF - Advances in Space Research Y1 - 2009 SN - 0273-1177 VL - 44 IS - 11 SP - 1345 EP - 1353 ER - TY - JOUR A1 - Havermann, Marc A1 - Salve, M. de A1 - Tin, G. del A1 - Panella, B. T1 - Experimental Study of the Temperature Field along a Density Lock / Salve, M. de ; Tin, G. del ; Panella, B. ; Sansoldo, D. ; Havermann, M. JF - Proceedings : International Conference on New Trends in Nuclear System Thermohydraulics, May 30th - June 2nd, 1994, Pisa / organized by Dipartimento di Costruzioni Meccaniche e Nucleari ... . Ed. by Francesco Oriolo Y1 - 1994 N1 - International Conference on New Trends in Nuclear System Thermohydraulics ; (1994.05.30-06.02 ; Pisa) SP - 623 EP - 630 PB - - CY - Pisa ER - TY - JOUR A1 - Havermann, Marc A1 - Beylich, A. E. T1 - Combined Measurement of Velocity, Temperature and Pressure in Compressible Gas Flows Using Laser-Induced Iodine Fluorescence / Havermann, M. ; Beylich, A. E. Y1 - 1998 N1 - 9th International Symposium on Applications of Laser Techniques to Fluid Mechanics, Lisbon (Portugal), 1998 PB - - ER - TY - JOUR A1 - Havermann, Marc A1 - Seiler, F. A1 - George, A. A1 - Leopold, F. T1 - Enhanced Doppler Picture Velocimetry (DPV) for Planar Velocity Measurements in High-Speed Shock Tunnel Flow / Seiler, F. ; George, A. ; Leopold, F. ; Havermann, M. ; Srulijes, J. JF - 10th International Symposium on Flow Visualization : Kyōto, Japan, August 26 - 29, 2002 / sponsored by International Flow Visualization Society . [Chairman:] Toshio Kobayashi Y1 - 2002 SN - 4906497829 N1 - International Symposium on Flow Visualization ; (10 ; 2002.08.26-29 ; Kyōto) PB - Visualization Society of Japan CY - Kyoto ER - TY - JOUR A1 - Ley, Wilfried A1 - Plescher, Engelbert A1 - Scholz, Artur A1 - Piepenbrock, Johannes T1 - COMPASS-1 picosatellite project / Ley, Wilfried ; Plescher, Engelbert ; Scholz, Artur ; Piepenbrock, Johannes JF - Small satellites for earth observation : digest of the 6th International symposium of the International Academy of Astronautics, Berlin, April 23 - 26, 2007 / ed. by Rainer Sandau; Hans-Peter Röser; Arnoldo Valenzuela Y1 - 2007 SN - 9783896855718 N1 - Symposium on Small Satellites for Earth Observation ; (6, 2007, Berlin) SP - 147 EP - 150 PB - Wissenschaft und Technik Verl. CY - Berlin ER - TY - JOUR A1 - Wittmann, Klaus A1 - Kehr, J. A1 - Willnecker, R. T1 - Decentralized Payload Operations Concept for Columbus Y1 - 2000 N1 - 51st IAF Congress, Rio de Janeiro, Brazil, Oct. 2000 ER - TY - JOUR A1 - Wittmann, Klaus A1 - Bibring, J.-P. A1 - Rosenbauer, H. A1 - Boehnhardt, H. T1 - The Rosetta Lander (“Philae”) Investigations / Bibring, J.-P. ; Rosenbauer, H. ; Boehnhardt, H. ; [...] Wittmann, K. JF - Space Science Reviews. 128 (2007), H. 1-4 Y1 - 2007 SN - 0038-6308 SP - 205 EP - 220 ER - TY - JOUR A1 - Röth, Thilo A1 - Schreiber, Harold T1 - CAKE (Computer Aided Kinematic Engineering) im Karrosseriebau und in der passiven Fahrzeugsicherheit / Schreiber , Harold ; Röth, Thilo JF - Mobiles. 2002/2003 (2003), H. 33 Y1 - 2003 N1 - in der Bibliothek Eupener Str. vorhanden SP - 65 EP - 67 ER - TY - JOUR A1 - Röth, Thilo A1 - Nowack, N. A1 - Baumeister, E. T1 - Numerische Lösungsansätze zur Auslegung von Stahl-Leichtmetall-Hybriden aus Verbundguss für zukünftige Fahrzeugstrukturen / Nowack, N. ; Röth, T. ; Baumeister, E. JF - Berechnung und Simulation im Fahrzeugbau. Bd. 1 : Tagung Würzburg, 27. und 28. September 2006 = Numerical analysis and simulation in vehicle engineering / VDI-Gesellschaft Fahrzeug- und Verkehrstechnik Y1 - 2006 SN - 3-18-091967-1 N1 - VDI-Berichte ; 1967 SP - 363 EP - 368 PB - VDI-Verl. CY - Düsseldorf ER - TY - JOUR A1 - Wittmann, Klaus T1 - Overview of Space Operations at DLR Y1 - 2000 N1 - SpaceOps2000 Conference, Toulouse, Frankreich,19-23 June 2000 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 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 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 - 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 - Bohn, Dieter A1 - Funke, Harald T1 - Experimental investigations into the nonuniform flow in a 4-stage turbine with special focus on the flow equalization in the first turbine stage JF - ASME TURBO EXPO, Proceedings of the ASME Turbo Expo, 2003 Y1 - 2003 SN - 0-7918-3689-4 N1 - ASME TURBO EXPO 2003, Proceedings, Vol. 6: Turbomachinery, Pt. A, Atlanta, US, Jun 16-19, 2003 SP - 281 EP - 289 ER - TY - JOUR A1 - Gerhardt, Hans Joachim T1 - Design methods of smoke and heat exhaust systems in construction works JF - V Mie̜dzynarodowa Konferencja Bezpieczeństwo Pożarowe Budowli, Warszawa-Miedzeszyn, 14 - 16 listopada 2005 r. = : Vth International Conference Fire Safety of Buildings / ITB ... [Ed. Mirosław Kosiorek] Y1 - 2005 SN - 83-7413-810-6 N1 - Mie̜dzynarodowa Konferencja Bezpieczeństwo Pożarowe Budowli <5, 2005, Warszawa> ; International Conference Fire Safety of Buildings <5, 2005, Warszawa-Miedzeszyn> SP - 127 EP - 140 PB - ITB CY - Warszawa ER - TY - JOUR A1 - Gerhardt, Hans Joachim A1 - Schönwald, J. A1 - Forßmann, R. A1 - Große, Wolfgang T1 - Modulation der Windenergie durch optimierte Uferbepflanzung zur Steuerung der Oberflächenströmung für das Entfernung von Treibgut JF - Der Fühlinger See : Beiträge zur Erhaltung der ökologischen Qualität / hrsg. von Wolfgang Große ... - (Ökologie und nachhaltige Entwicklung von Sport- und Freizeitseen ; 1) Y1 - 2005 SN - 3-86582-212-6 SP - 95 EP - 108 PB - Monsenstein und Vannerdat CY - Münster ER - TY - JOUR A1 - Gerhardt, Hans Joachim T1 - Wind- und Temperatureinflüsse bei der Planung von Entrauchungseinrichtungen JF - VFDB-Zeitschrift : Forschung, Technik und Management im Brandschutz. 55 (2006), H. 3 Y1 - 2006 SN - 0042-1804 SP - 115 EP - 121 ER - TY - JOUR A1 - Gerhardt, Hans Joachim A1 - Konrath, B. A1 - Stiel, M. T1 - Anmerkungen zur DIN EN 12101-2 über die Prüfung von natürlichen Rauch- und Wärmeabzugsanlagen (NRGW) JF - VFDB-Zeitschrift : Forschung, Technik und Management im Brandschutz. 55 (2006), H. 3 Y1 - 2006 SN - 0042-1804 SP - 157 EP - 158 ER - TY - JOUR A1 - Gerhardt, Hans Joachim A1 - Schönwald, J. A1 - Konrath, B. T1 - Verwendung von Leichtgas bei Brandsimulationen - unzulässig oder sinnvoll? JF - VFDB-Zeitschrift : Forschung, Technik und Management im Brandschutz. 56 (2007), H. 1 Y1 - 2007 SN - 0042-1804 SP - 29 EP - 31 ER - TY - JOUR A1 - Gerhardt, Hans Joachim A1 - Konrath, B. A1 - Schönwald, J. T1 - Brandsimulation für Abnahmeversuche JF - HLH : Lüftung, Klima, Heizung, Sanitär, Gebäudetechnik. 56 (2005), H. 8 Y1 - 2005 SN - 1436-5103 N1 - 2. ISSN: 0017-9906 ; 3. ISSN: 1434-422X ; Zeitschrift unter 13 Z 739 in der Bibliothek SP - 46 EP - 51 ER - TY - JOUR A1 - Gerhardt, Hans Joachim A1 - Konrath, B. A1 - Lieb, R.-D. T1 - Das Drallrohr JF - HLH : Lüftung, Klima, Heizung, Sanitär, Gebäudetechnik. 56 (2005), H. 11 Y1 - 2005 SN - 1436-5103 N1 - 2. ISSN: 0017-9906 ; 3. ISSN: 1434-422X ; Zeitschrift unter 13 Z 739 in der Bibliothek SP - 91 EP - 95 ER - TY - JOUR A1 - Gerhardt, Hans Joachim A1 - Krüger, O. T1 - Building shape influence on local wind loads JF - Proceedings of the 2nd European & African Conference on Wind Engineering : 2 EACWE, Palazzo Ducale, Genova, Italy, June 22-26, 1997 / ed. by Giovanni Solari. - Vol. 2 Y1 - 1997 SN - 88-86281-19-6 N1 - European and African Conference on Wind Engineering <2, 1997, Genova> ; ISBN für beide Bände PB - Servizi Grafici Editoriali CY - Padova ER - TY - JOUR A1 - Gerhardt, Hans Joachim T1 - Teures Bauen durch starre Genehmigungspraxis JF - Der Bausachverständige : Zeitschrift für Bauschäden, Grundstückswert und gutachterliche Tätigkeit. 1 (2005), H. 5 Y1 - 2005 SN - 1614-6123 SP - 44 EP - 45 ER - TY - JOUR A1 - Gerhardt, Hans Joachim A1 - Lieb, R.-D. T1 - Entrauchung komplexer Räumlichkeiten : Strategien und Steuerungen JF - Tür-Tor-Fenster-Report : Fachzeitschrift für die Technologien von Türen, Toren und Fenstern. 25 (2005), H. 3 Y1 - 2005 SN - 0724-7702 SP - 27 EP - 29 ER - TY - JOUR A1 - Gerhardt, Hans Joachim T1 - Physikalische Modelle für Brandsicherheitsnachweise = physical models for fire safety design JF - Kurzreferate : Hannover, 6. und 7. Juni 2005 = Proceedings / [Veranst.: VFDB, Vereinigung zur Förderung des Deutschen Brandschutzes e.V.; iBMB, Institut für Baustoffe, Massivbau und Brandschutz der Technischen Universität Braunschweig]. Hrsg.: Dietmar Hosser Y1 - 2005 SN - 3-89288-165-0 N1 - Internationales Brandschutz-Symposium <10, 2005, Hannover> SP - 135 EP - 154 PB - iBMB CY - Braunschweig ER - TY - JOUR A1 - Scholz, A. A1 - Ley, Wilfried A1 - Dachwald, Bernd A1 - Miau, J. J. A1 - Juang, J. C. T1 - Flight results of the COMPASS-1 picosatellite mission JF - Acta Astronautica. 67 (2010), H. 9-10 Y1 - 2010 SN - 0094-5765 SP - 1289 EP - 1298 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Seboldt, Wolfgang T1 - Solar sailcraft of the first generation mission applications to near-earth asteroids Y1 - 2003 N1 - 54th International Astronautical Congress of the International Astronautical Federation, the International Academy of Astronautics, and the International Institute of Space Law 29 September - 3 October 2003, Bremen, Germany IAC-03-Q.5.06 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Tsinas, L. T1 - A combined neural and genetic learning algorithm / Tsinas, L. ; Dachwald, B. JF - Proceedings of the First IEEE Conference on Evolutionary Computation, 1994. IEEE World Congress on Computational Intelligence. Y1 - 1994 SN - 0-7803-1899-4 SP - 770 EP - 774 CY - Orlando, Fl ER - TY - JOUR A1 - Dachwald, Bernd A1 - Seboldt, Wolfgang T1 - Solar sailcraft of the first generation technology development / Seboldt, Wolfgang ; Dachwald, Bernd Y1 - 2003 N1 - 54th International Astronautical Congress of the International Astronautical Federation, the International Academy of Astronautics, and the International Institute of Space Law 29 September - 3 October 2003, Bremen, Germany IAC-03-S.03 ER - TY - JOUR A1 - Krämer, Stefan A1 - Daab, Dominique Jonas A1 - Müller, Brigitte A1 - Wagner, Tobias A1 - Baader, Fabian A1 - Hessel, Joana A1 - Gdalewitsch, Georg A1 - Plescher, Engelbert A1 - Dachwald, Bernd A1 - Wahle, Michael A1 - Gierse, Andreas A1 - Vetter, Rudolf A1 - Pfützenreuter, Lysan T1 - Development and flight-testing of a system to isolate vibrations for microgravity experiments on sounding rockets JF - 21st ESA Symposium on Rocket and Balloon Research Y1 - 2013 SP - 1 EP - 8 ER - TY - JOUR A1 - Funke, Harald A1 - Dickhoff, J. A1 - Keinz, Jan A1 - Anis, H. A. A1 - Parente, A. A1 - Hendrick, P. T1 - Experimental and numerical study of the micromix combustion principle applied for hydrogen and hydrogen-rich syngas as fuel with increased energy density for industrial gas turbine applications JF - Energy procedia N2 - The Dry Low NOx (DLN) Micromix combustion principle with increased energy density is adapted for the industrial gas turbine APU GTCP 36-300 using hydrogen and hydrogen-rich syngas with a composition of 90%-Vol. hydrogen (H₂) and 10%-Vol. carbon-monoxide (CO). Experimental and numerical studies of several combustor geometries for hydrogen and syngas show the successful advance of the DLN Micromix combustion from pure hydrogen to hydrogen-rich syngas. The impact of the different fuel properties on the combustion principle and aerodynamic flame stabilization design laws, flow field, flame structure and emission characteristics is investigated by numerical analysis using a hybrid Eddy Break Up combustion model and validated against experimental results. Y1 - 2014 U6 - https://doi.org/10.1016/j.egypro.2014.12.201 SN - 1876-6102 (E-Journal) IS - 61 SP - 1736 EP - 1739 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Schirra, Julian A1 - Watmuff, Jonathan A1 - Bauschat, J.-Michael T1 - Highly non-planar lifting systems: a relative assessment of existing potential-methodologies to accurately estimate the induced drag JF - 32nd AIAA Applied Aerodynamics Conference 2014 : June, 16-20 2014, Atlanta, Ga. Y1 - 2014 SN - 978-1-62410-288-2 U6 - https://doi.org/10.2514/6.2014-2988 SP - Publ. online ER - TY - JOUR A1 - Haj Ayed, A. A1 - Kusterer, K. A1 - Funke, Harald A1 - Keinz, Jan A1 - Striegan, Constantin A1 - Bohn, D. T1 - Experimental and numerical investigations of the dry-low-NOx hydrogen micromix combustion chamber of an industrial gas turbine JF - Propulsion and power research Y1 - 2015 U6 - https://doi.org/10.1016/j.jppr.2015.07.005 SN - 2212-540X VL - Vol. 4 IS - Iss. 3 SP - 123 EP - 131 ER - TY - JOUR A1 - Haj Ayed, A. A1 - Kusterer, K. A1 - Funke, Harald A1 - Keinz, Jan A1 - Striegan, Constantin A1 - Bohn, D. T1 - Improvement study for the dry-low-NOx hydrogen micromix combustion technology JF - Propulsion and power research Y1 - 2015 U6 - https://doi.org/10.1016/j.jppr.2015.07.003 SN - 2212-540X VL - Vol. 4 IS - Iss. 3 SP - 132 EP - 140 ER - TY - JOUR A1 - Bindal, Gaurav A1 - Sharma, Sparsh A1 - Janser, Frank A1 - Neu, Eugen T1 - Detailed analysis of variables affecting wing kinematics of bat flight JF - SAE International Journal of Aerospace Y1 - 2013 U6 - https://doi.org/10.4271/2013-01-9003 SN - 1946-3901 VL - 6 IS - 2 SP - 811 EP - 818 ER - TY - JOUR A1 - Schüller, K. A1 - Kowalski, Julia A1 - Raback, P. T1 - Curvilinear melting – A preliminary experimental and numerical study JF - International Journal of Heat and Mass Transfer N2 - When exploring glacier ice it is often necessary to take samples or implement sensors at a certain depth underneath the glacier surface. One way of doing this is by using heated melting probes. In their common form these devices experience a straight one-dimensional downwards motion and can be modeled by standard close-contact melting theory. A recently developed melting probe however, the IceMole, achieves maneuverability by simultaneously applying a surface temperature gradient to induce a change in melting direction and controlling the effective contact-force by means of an ice screw to stabilize its change in attitude. A modeling framework for forced curvilinear melting does not exist so far and will be the content of this paper. At first, we will extend the existing theory for quasi-stationary close-contact melting to curved trajectories. We do this by introducing a rotational mode. This additional unknown in the system implies yet the need for another model closure. Within this new framework we will focus on the effect of a variable contact-force as well as different surface temperature profiles. In order to solve for melting velocity and curvature of the melting path we present both an inverse solution strategy for the analytical model, and a more general finite element framework implemented into the open source software package ELMER. Model results are discussed and compared to experimental data conducted in laboratory tests. Y1 - 2016 U6 - https://doi.org/10.1016/j.ijheatmasstransfer.2015.09.046 SN - 0017-9310 IS - 92 SP - 884 EP - 892 PB - Elsevier CY - Amsterdam 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 - JOUR A1 - Konstantinidis, Konstantinos A1 - Flores Martinez, Claudio A1 - Dachwald, Bernd A1 - Ohndorf, Andreas A1 - Dykta, Paul A1 - Bowitz, Pascal A1 - Rudolph, Martin A1 - Digel, Ilya A1 - Kowalski, Julia A1 - Voigt, Konstantin A1 - Förstner, Roger T1 - A lander mission to probe subglacial water on Saturn's moon enceladus for life JF - Acta astronautica Y1 - 2015 SN - 1879-2030 (E-Journal); 0094-5765 (Print) VL - Vol. 106 SP - 63 EP - 89 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Stadler, Alexander Maximilian A1 - Garvey, Christopher J. A1 - Embs, Jan Peter A1 - Koza, Michael Marek A1 - Unruh, Tobias A1 - Artmann, Gerhard A1 - Zaccai, Guiseppe T1 - Picosecond dynamics in haemoglobin from different species: A quasielastic neutron scattering study JF - Biochimica et biophysica acta (BBA): General Subjects Y1 - 2014 U6 - https://doi.org/10.1016/j.bbagen.2014.06.007 SN - 1872-8006 (E-Journal); 0304-4165 (Print) VL - 1840 IS - 10 SP - 2989 EP - 2999 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Dachwald, Bernd A1 - Mikucki, Jill A1 - Tulaczyk, Slawek A1 - Digel, Ilya A1 - Espe, Clemens A1 - Feldmann, Marco A1 - Francke, Gero A1 - Kowalski, Julia A1 - Xu, Changsheng T1 - IceMole : A maneuverable probe for clean in situ analysis and sampling of subsurface ice and subglacial aquatic ecosystems JF - Annals of Glaciology N2 - There is significant interest in sampling subglacial environments for geobiological studies, but they are difficult to access. Existing ice-drilling technologies make it cumbersome to maintain microbiologically clean access for sample acquisition and environmental stewardship of potentially fragile subglacial aquatic ecosystems. The IceMole is a maneuverable subsurface ice probe for clean in situ analysis and sampling of glacial ice and subglacial materials. The design is based on the novel concept of combining melting and mechanical propulsion. It can change melting direction by differential heating of the melting head and optional side-wall heaters. The first two prototypes were successfully tested between 2010 and 2012 on glaciers in Switzerland and Iceland. They demonstrated downward, horizontal and upward melting, as well as curve driving and dirt layer penetration. A more advanced probe is currently under development as part of the Enceladus Explorer (EnEx) project. It offers systems for obstacle avoidance, target detection, and navigation in ice. For the EnEx-IceMole, we will pay particular attention to clean protocols for the sampling of subglacial materials for biogeochemical analysis. We plan to use this probe for clean access into a unique subglacial aquatic environment at Blood Falls, Antarctica, with return of a subglacial brine sample. KW - Antarctic Glaciology KW - Extraterrestrial Glaciology KW - Glaciological instruments and methods KW - Subclacial exploration KW - Subglacial lakes Y1 - 2014 U6 - https://doi.org/10.3189/2014AoG65A004 SN - 1727-5644 VL - 55 IS - 65 SP - 14 EP - 22 PB - Cambridge University Press CY - Cambridge 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 - https://doi.org/10.1088/0957-0233/16/2/003 SN - 0957-0233 VL - Vol. 16 IS - No. 2 SP - 336 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 - Hoeveler, Bastian A1 - Janser, Frank A1 - Bindewald, Thorsten A1 - Gebhardt, Andreas T1 - Entwurf, Fertigung und Untersuchung eines Windkanalmodells eines innovativen, senkrechtstartenden Kleinflugzeuges JF - RTejournal - Forum für Rapid Technologie Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0009-2-42921 SN - 1614-0923 IS - 12 SP - 1 EP - 5 PB - Fachhochschule Aachen CY - Aachen ER - TY - JOUR A1 - Kowalski, Julia A1 - Linder, Peter A1 - Zierke, S. A1 - Wulfen, B. van A1 - Clemens, J. A1 - Konstantinidis, K. A1 - Ameres, G. A1 - Hoffmann, R. A1 - Mikucki, J. A1 - Tulaczyk, S. A1 - Funke, O. A1 - Blandfort, D. A1 - Espe, Clemens A1 - Feldmann, Marco A1 - Francke, Gero A1 - Hiecker, S. A1 - Plescher, Engelbert A1 - Schöngarth, Sarah A1 - Dachwald, Bernd A1 - Digel, Ilya A1 - Artmann, Gerhard A1 - Eliseev, D. A1 - Heinen, D. A1 - Scholz, F. A1 - Wiebusch, C. A1 - Macht, S. A1 - Bestmann, U. A1 - Reineking, T. A1 - Zetzsche, C. A1 - Schill, K. A1 - Förstner, R. A1 - Niedermeier, H. A1 - Szumski, A. A1 - Eissfeller, B. A1 - Naumann, U. A1 - Helbing, K. T1 - Navigation technology for exploration of glacier ice with maneuverable melting probes JF - Cold Regions Science and Technology N2 - The Saturnian moon Enceladus with its extensive water bodies underneath a thick ice sheet cover is a potential candidate for extraterrestrial life. Direct exploration of such extraterrestrial aquatic ecosystems requires advanced access and sampling technologies with a high level of autonomy. A new technological approach has been developed as part of the collaborative research project Enceladus Explorer (EnEx). The concept is based upon a minimally invasive melting probe called the IceMole. The force-regulated, heater-controlled IceMole is able to travel along a curved trajectory as well as upwards. Hence, it allows maneuvers which may be necessary for obstacle avoidance or target selection. Maneuverability, however, necessitates a sophisticated on-board navigation system capable of autonomous operations. The development of such a navigational system has been the focal part of the EnEx project. The original IceMole has been further developed to include relative positioning based on in-ice attitude determination, acoustic positioning, ultrasonic obstacle and target detection integrated through a high-level sensor fusion. This paper describes the EnEx technology and discusses implications for an actual extraterrestrial mission concept. Y1 - 2016 U6 - https://doi.org/10.1016/j.coldregions.2015.11.006 SN - 0165-232X IS - 123 SP - 53 EP - 70 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Grundmann, Jan Thimo A1 - Dachwald, Bernd A1 - Grimm, Christian D. A1 - Kahle, Ralph A1 - Koch, Aaron Dexter A1 - Krause, Christian A1 - Lange, Caroline A1 - Quantius, Dominik A1 - Ulamec, Stephan T1 - Spacecraft for Hypervelocity Impact Research – An Overview of Capabilities, Constraints and the Challenges of Getting There JF - Procedia Engineering Y1 - 2015 U6 - https://doi.org/10.1016/j.proeng.2015.04.021 SN - 1877-7058 N1 - Proceedings of the 2015 Hypervelocity Impact Symposium (HVIS 2015) VL - Vol. 103 SP - 151 EP - 158 PB - Elsevier CY - Amsterdam 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 - https://doi.org/10.1016/j.ast.2015.11.032 SN - 1270-9638 VL - 49 SP - 73 EP - 79 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Funke, Harald A1 - Beckmann, Nils A1 - Keinz, Jan A1 - Abanteriba, Sylvester T1 - Comparison of Numerical Combustion Models for Hydrogen and Hydrogen-Rich Syngas Applied for Dry-Low-Nox-Micromix-Combustion JF - Journal of Engineering for Gas Turbines and Power N2 - The Dry-Low-NOx (DLN) Micromix combustion technology has been developed as low emission combustion principle for industrial gas turbines fueled with hydrogen or syngas. The combustion process is based on the phenomenon of jet-in-crossflow-mixing (JICF). Fuel is injected perpendicular into the air-cross-flow and burned in a multitude of miniaturized, diffusion-like flames. The miniaturization of the flames leads to a significant reduction of NOx emissions due to the very short residence time of reactants in the flame. In the Micromix research approach, computational fluid dynamics (CFD) analyses are validated toward experimental results. The combination of numerical and experimental methods allows an efficient design and optimization of DLN Micromix combustors concerning combustion stability and low NOx emissions. The paper presents a comparison of several numerical combustion models for hydrogen and hydrogen-rich syngas. They differ in the complexity of the underlying reaction mechanism and the associated computational effort. The performance of a hybrid eddy-break-up (EBU) model with a one-step global reaction is compared to a complex chemistry model and a flamelet generated manifolds (FGM) model, both using detailed reaction schemes for hydrogen or syngas combustion. Validation of numerical results is based on exhaust gas compositions available from experimental investigation on DLN Micromix combustors. The conducted evaluation confirms that the applied detailed combustion mechanisms are able to predict the general physics of the DLN-Micromix combustion process accurately. The FGM method proved to be generally suitable to reduce the computational effort while maintaining the accuracy of detailed chemistry. Y1 - 2018 U6 - https://doi.org/10.1115/1.4038882 SN - 0742-4795 N1 - Article number 081504; Paper No: GTP-17-1567 VL - 140 IS - 8 PB - ASME CY - New York, NY ER - TY - JOUR A1 - Röth, Thilo A1 - Pielen, Michael A1 - Wolff, Klaus A1 - Lüdiger, Thomas T1 - Urbane Fahrzeugkonzepte für die Shared Mobility JF - Automobiltechnische Zeitschrift - ATZ N2 - Urbane Mobilitätskonzepte der Zukunft erfordern neue Unternehmensformen, idealerweise aus Old Economy und New Economy, sowie eine enge Anbindung an die gesellschaftsrelevante Zukunftsforschung. Für neue Fahrzeugkonzepte des Carsharing bedeutet dies, dass alle kostenverursachenden Faktoren erfasst und analysiert werden müssen. Die FH Aachen, share2drive und FEV geben einen Ausblick auf die zukünftige Fahrzeugklasse der Personal Public Vehicles als „Rolling Device“. Y1 - 2018 U6 - https://doi.org/10.1007/s35148-017-0176-8 SN - 0001-2785 VL - 120 IS - 1 SP - 18 EP - 23 PB - Springer Vieweg CY - Wiesbaden ER - TY - JOUR A1 - Schirra, Julian A1 - Bissonnette, William A1 - Bramesfeld, Götz T1 - Wake-model effects on induced drag prediction of staggered boxwings JF - Aerospace Y1 - 2018 U6 - https://doi.org/10.3390/aerospace5010014 SN - 2226-4310 VL - 5 IS - 1 ER - TY - JOUR A1 - Weihe, Stefan A1 - Ansgar, Ernst A1 - Röth, Thilo A1 - Proksch, Johannes T1 - Leichtmetall-Stahl-Verbundguss im Nutzfahrzeugbau JF - Lightweight Design N2 - In modernen Fahrzeugkarosserien der Großserie kommen zunehmend Materialmischbauweisen zur Anwendung. In Zusammenarbeit der Daimler AG, der Tower Automotive Holding GmbH, der Imperia GmbH sowie der Partnerunternehmen KSM Castings GmbH und Schaufler Tooling GmbH & Co. KG wird das Leichtbaupotenzial von Stahlblech-AluminiumverbundgussHybriden am Beispiel des vorderen Dachquerträgers des Mercedes-Benz Viano/Vito ausführlich untersucht. Y1 - 2013 SN - 2192-8738 (Online) SN - 1865-4819 (Print) VL - 6 IS - 2 SP - 38 EP - 43 PB - Springer CY - Berlin ER - TY - JOUR A1 - Weihe, Stefan A1 - Ernst, Ansgar A1 - Röth, Thilo A1 - Proksch, Johannes T1 - Aluminium-Stahl-Verbundguss im Nutzfahrzeugbau JF - ATZ - Automobiltechnische Zeitschrift N2 - In modernen Fahrzeugkarosserien der Großserie kommen zunehmend Materialmischbauweisen zur Anwendung. In Zusammenarbeit der Daimler AG, der Tower Automotive Holding GmbH, der Imperia GmbH sowie der Partnerunternehmen KSM Castings GmbH und Schaufler Tooling GmbH & Co. KG wird das Leichtbaupotenzial von Aluminiumverbundguss-Stahlblech-Hybriden am Beispiel des vorderen Dachquerträgers des Mercedes-Benz Viano/Vito ausführlich untersucht. Y1 - 2013 SN - 2192-8800 (Online) SN - 0001-2785 (Print) VL - 115 IS - 4 SP - 312 EP - 316 PB - Springer Fachmedien Wiesbaden 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 - https://doi.org/10.1029/2018JG004411 SN - 2169-8961 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Campen, R. A1 - Kowalski, Julia A1 - Lyons, W.B. A1 - Tulaczyk, S. A1 - Dachwald, Bernd A1 - Pettit, E. A1 - Welch, K. A. A1 - Mikucki, J.A. T1 - Microbial diversity of an Antarctic subglacial community and high‐resolution replicate sampling inform hydrological connectivity in a polar desert JF - Environmental Microbiology Y1 - 2019 U6 - https://doi.org/10.1111/1462-2920.14607 SN - 1462-2920 IS - accepted article PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Jan Thimo, Grundmann A1 - Bauer, Waldemar A1 - Biele, Jens A1 - Boden, Ralf A1 - Ceriotti, Matteo A1 - Cordero, Federico A1 - Dachwald, Bernd A1 - Dumont, Etienne A1 - Grimm, Christian D. A1 - Hercik, David T1 - Capabilities of Gossamer-1 derived small spacecraft solar sails carrying Mascot-derived nanolanders for in-situ surveying of NEAs JF - Acta Astronautica Y1 - 2019 U6 - https://doi.org/10.1016/j.actaastro.2018.03.019 SN - 0094-5765 VL - 156 IS - 3 SP - 330 EP - 362 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Funke, Harald A1 - Beckmann, Nils A1 - Abanteriba, Sylvester T1 - An overview on dry low NOx micromix combustor development for hydrogen-rich gas turbine applications JF - International Journal of Hydrogen Energy Y1 - 2019 U6 - https://doi.org/10.1016/j.ijhydene.2019.01.161 SN - 0360-3199 VL - 44 IS - 13 SP - 6978 EP - 6990 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Finger, Felix A1 - Bil, Cees A1 - Braun, Carsten T1 - Initial Sizing Methodology for Hybrid-Electric General Aviation Aircraft JF - Journal of Aircraft Y1 - 2019 U6 - https://doi.org/10.2514/1.C035428 SN - 1533-3868 VL - 57 IS - 2 SP - 245 EP - 255 ER - TY - JOUR A1 - Bergmann, Ole A1 - Götten, Falk A1 - Braun, Carsten A1 - Janser, Frank T1 - Comparison and evaluation of blade element methods against RANS simulations and test data JF - CEAS Aeronautical Journal N2 - This paper compares several blade element theory (BET) method-based propeller simulation tools, including an evaluation against static propeller ground tests and high-fidelity Reynolds-Average Navier Stokes (RANS) simulations. Two proprietary propeller geometries for paraglider applications are analysed in static and flight conditions. The RANS simulations are validated with the static test data and used as a reference for comparing the BET in flight conditions. The comparison includes the analysis of varying 2D aerodynamic airfoil parameters and different induced velocity calculation methods. The evaluation of the BET propeller simulation tools shows the strength of the BET tools compared to RANS simulations. The RANS simulations underpredict static experimental data within 10% relative error, while appropriate BET tools overpredict the RANS results by 15–20% relative error. A variation in 2D aerodynamic data depicts the need for highly accurate 2D data for accurate BET results. The nonlinear BET coupled with XFOIL for the 2D aerodynamic data matches best with RANS in static operation and flight conditions. The novel BET tool PropCODE combines both approaches and offers further correction models for highly accurate static and flight condition results. KW - BET KW - CFD propeller simulation KW - Propeller aerodynamics KW - Actuator disk modelling KW - Propeller performance Y1 - 2022 U6 - https://doi.org/10.1007/s13272-022-00579-1 SN - 1869-5590 (Online) SN - 1869-5582 (Print) N1 - Corresponding author: Ole Bergmann VL - 13 SP - 535 EP - 557 PB - Springer CY - Wien ER - TY - JOUR A1 - Kreyer, Jörg A1 - Müller, Marvin A1 - Esch, Thomas T1 - A Calculation Methodology for Predicting Exhaust Mass Flows and Exhaust Temperature Profiles for Heavy-Duty Vehicles JF - SAE International Journal of Commercial Vehicles N2 - The predictive control of commercial vehicle energy management systems, such as vehicle thermal management or waste heat recovery (WHR) systems, are discussed on the basis of information sources from the field of environment recognition and in combination with the determination of the vehicle system condition. In this article, a mathematical method for predicting the exhaust gas mass flow and the exhaust gas temperature is presented based on driving data of a heavy-duty vehicle. The prediction refers to the conditions of the exhaust gas at the inlet of the exhaust gas recirculation (EGR) cooler and at the outlet of the exhaust gas aftertreatment system (EAT). The heavy-duty vehicle was operated on the motorway to investigate the characteristic operational profile. In addition to the use of road gradient profile data, an evaluation of the continuously recorded distance signal, which represents the distance between the test vehicle and the road user ahead, is included in the prediction model. Using a Fourier analysis, the trajectory of the vehicle speed is determined for a defined prediction horizon. To verify the method, a holistic simulation model consisting of several hierarchically structured submodels has been developed. A map-based submodel of a combustion engine is used to determine the EGR and EAT exhaust gas mass flows and exhaust gas temperature profiles. All simulation results are validated on the basis of the recorded vehicle and environmental data. Deviations from the predicted values are analyzed and discussed. Y1 - 2020 U6 - https://doi.org/10.4271/02-13-02-0009 SN - 1946-3928 VL - 13 IS - 2 SP - 129 EP - 143 PB - SAE International CY - Warrendale, Pa. ER - TY - JOUR A1 - Götten, Falk A1 - Havermann, Marc A1 - Braun, Carsten A1 - Marino, Matthew A1 - Bil, Cees T1 - Wind-tunnel and CFD investigations of UAV landing gears and turrets – Improvements in empirical drag estimation JF - Aerospace Science and Technology N2 - This paper analyzes the drag characteristics of several landing gear and turret configurations that are representative of unmanned aircraft tricycle landing gears and sensor turrets. A variety of these components were constructed via 3D-printing and analyzed in a wind-tunnel measurement campaign. Both turrets and landing gears were attached to a modular fuselage that supported both isolated components and multiple components at a time. Selected cases were numerically investigated with a Reynolds-averaged Navier-Stokes approach that showed good accuracy when compared to wind-tunnel data. The drag of main gear struts could be significantly reduced via streamlining their cross-sectional shape and keeping load carrying capabilities similar. The attachment of wheels introduced interference effects that increased strut drag moderately but significantly increased wheel drag compared to isolated cases. Very similar behavior was identified for front landing gears. The drag of an electro-optical and infrared sensor turret was found to be much higher than compared to available data of a clean hemisphere-cylinder combination. This turret drag was merely influenced by geometrical features like sensor surfaces and the rotational mechanism. The new data of this study is used to develop simple drag estimation recommendations for main and front landing gear struts and wheels as well as sensor turrets. These recommendations take geometrical considerations and interference effects into account. Y1 - 2020 U6 - https://doi.org/10.1016/j.ast.2020.106306 SN - 1270-9638 VL - 107 IS - Art. 106306 PB - Elsevier CY - Amsterdam 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 - https://doi.org/10.1016/j.simpat.2020.102173 SN - 1569-190X VL - 106 IS - Art. 102173 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Götten, Falk A1 - Havermann, Marc A1 - Braun, Carsten A1 - Marino, Matthew A1 - Bil, Cees T1 - Improved Form Factor for Drag Estimation of Fuselages with Various Cross Sections JF - Journal of Aircraft N2 - The paper presents an aerodynamic investigation of 70 different streamlined bodies with fineness ratios ranging from 2 to 10. The bodies are chosen to idealize both unmanned and small manned aircraft fuselages and feature cross-sectional shapes that vary from circular to quadratic. The study focuses on friction and pressure drag in dependency of the individual body’s fineness ratio and cross section. The drag forces are normalized with the respective body’s wetted area to comply with an empirical drag estimation procedure. Although the friction drag coefficient then stays rather constant for all bodies, their pressure drag coefficients decrease with an increase in fineness ratio. Referring the pressure drag coefficient to the bodies’ cross-sectional areas shows a distinct pressure drag minimum at a fineness ratio of about three. The pressure drag of bodies with a quadratic cross section is generally higher than for bodies of revolution. The results are used to derive an improved form factor that can be employed in a classic empirical drag estimation method. The improved formulation takes both the fineness ratio and cross-sectional shape into account. It shows superior accuracy in estimating streamlined body drag when compared with experimental data and other form factor formulations of the literature. Y1 - 2020 U6 - https://doi.org/10.2514/1.C036032 SN - 1533-3868 SP - 1 EP - 13 PB - AIAA CY - Reston, Va. ER - TY - JOUR A1 - Finger, Felix A1 - Braun, Carsten A1 - Bil, Cees T1 - Comparative assessment of parallel-hybrid-electric propulsion systems for four different aircraft JF - Journal of Aircraft N2 - Until electric energy storage systems are ready to allow fully electric aircraft, the combination of combustion engine and electric motor as a hybrid-electric propulsion system seems to be a promising intermediate solution. Consequently, the design space for future aircraft is expanded considerably, as serial hybrid-electric, parallel hybrid-electric, fully electric, and conventional propulsion systems must all be considered. While the best propulsion system depends on a multitude of requirements and considerations, trends can be observed for certain types of aircraft and certain types of missions. This Paper provides insight into some factors that drive a new design toward either conventional or hybrid propulsion systems. General aviation aircraft, regional transport aircraft vertical takeoff and landing air taxis, and unmanned aerial vehicles are chosen as case studies. Typical missions for each class are considered, and the aircraft are analyzed regarding their takeoff mass and primary energy consumption. For these case studies, a high-level approach is chosen, using an initial sizing methodology. Only parallel-hybrid-electric powertrains are taken into account. Aeropropulsive interaction effects are neglected. Results indicate that hybrid-electric propulsion systems should be considered if the propulsion system is sized by short-duration power constraints. However, if the propulsion system is sized by a continuous power requirement, hybrid-electric systems offer hardly any benefit. Y1 - 2020 U6 - https://doi.org/10.2514/1.C035897 SN - 1533-3868 VL - 57 IS - 5 PB - AIAA CY - Reston, Va. ER - TY - JOUR A1 - Gazda, Quentin A1 - Maurischat, Andreas T1 - Special functions and Gauss-Thakur sums in higher rank and dimension Y1 - 2020 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Götten, Falk A1 - Finger, Felix A1 - Havermann, Marc A1 - Braun, Carsten A1 - Marino, M. A1 - Bil, C. T1 - Full configuration drag estimation of short-to-medium range fixed-wing UAVs and its impact on initial sizing optimization JF - CEAS Aeronautical Journal N2 - The paper presents the derivation of a new equivalent skin friction coefficient for estimating the parasitic drag of short-to-medium range fixed-wing unmanned aircraft. The new coefficient is derived from an aerodynamic analysis of ten different unmanned aircraft used for surveillance, reconnaissance, and search and rescue missions. The aircraft is simulated using a validated unsteady Reynolds-averaged Navier Stokes approach. The UAV’s parasitic drag is significantly influenced by the presence of miscellaneous components like fixed landing gears or electro-optical sensor turrets. These components are responsible for almost half of an unmanned aircraft’s total parasitic drag. The new equivalent skin friction coefficient accounts for these effects and is significantly higher compared to other aircraft categories. It is used to initially size an unmanned aircraft for a typical reconnaissance mission. The improved parasitic drag estimation yields a much heavier unmanned aircraft when compared to the sizing results using available drag data of manned aircraft. KW - Parasitic drag KW - UAV KW - CFD KW - Aircraft sizing Y1 - 2021 U6 - https://doi.org/10.1007/s13272-021-00522-w SN - 1869-5590 (Online) SN - 1869-5582 (Print) N1 - Corresponding author: Falk Götten VL - 12 SP - 589 EP - 603 PB - Springer CY - Berlin ER - TY - JOUR A1 - Schückhaus, Ulrich T1 - Die SkyCab-Erfinder im WFMG-Interview JF - Business in MG Y1 - 2020 N1 - Interview von WFMG – Wirtschaftsförderung Mönchengladbach GmbH, vertreten durch Dr. Ulrich Schückhaus IS - 1 SP - 6 EP - 7 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 - 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 - https://doi.org/10.1016/j.asr.2017.10.017 SN - 0273-1177 IS - In Press, Corrected Proof PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Billerbeck, Katrin A1 - Barnat, Miriam A1 - Knutzen, Sönke T1 - Kompetenzorientierung auf dem Prüfstand. Erprobung von Indikatoren für den Kulturwandel JF - Die Hochschullehre N2 - Der Beitrag fokussiert die Frage nach dem Stand des durch die Bologna-Reform angestoßenen Kulturwandels im Hinblick auf Kompetenzorientierung am Beispiel der Technischen Universität Hamburg (TUHH). An der TUHH wird bereits seit einigen Jahren daran gearbeitet, die Lehre grundlegend neu auszurichten. Hierfür setzt das hochschuldidaktische "Zentrum für Lehre und Lernen" (ZLL) verschiedene Maßnahmen ein, wie z.B. eine finanzielle und didaktische Unterstützung von Lehrenden bei der Umstellung ihrer Veranstaltungen, Weiterqualifizierungsangebote und Informationsmaterial. Die Maßnahmen ebenso wie die innovierten Veranstaltungen werden von Lehrenden und Studierenden gut evaluiert. Nach dem Ansatz des Constructive Alignments lässt sich jedoch davon ausgehen, dass der Bereich der Prüfungen für eine Einschätzung des Status Quo der Kompetenzorientierung besonders relevant ist. Dieser wird deshalb anhand der beiden Kriterien Prüfungsformate und Schwierigkeitsstufen von Prüfungsaufgaben näher beleuchtet, die eng mit der Kompetenzorientierung zusammen hängen. Ergebnisse hierzu aus einer universitätsweiten Datenbank zur Studienorganisation sowie aus einer Online-Umfrage unter Studierenden weisen darauf hin, dass das Prüfungsformat "Klausur" nach wie vor am stärksten verbreitet ist; zugleich sind die Studierenden nach einer Selbsteinschätzung in Prüfungen vorrangig mit Aufgaben auf den Taxonomieniveaus "Wiedergeben" und "Anwenden" konfrontiert. Dies lässt sich als Hinweis darauf interpretieren, dass es im Hinblick auf eine Kompetenzorientierung in den Prüfungen noch weiteren Veränderungsbedarf gibt. Y1 - 2016 U6 - https://doi.org/10.3278/HSL1616W SN - 2199-8825 VL - 2016 IS - 16 PB - WBV Media CY - Bielefeld ER - TY - JOUR A1 - Barnat, Miriam A1 - Faria, Joana Abelha A1 - Bosse, Elke T1 - Heterogenität und Studierfähigkeit: Erste Ergebnisse einer Längsschnittbefragung JF - Qualität in der Wissenschaft: QiW ; Zeitschrift für Qualitätsentwicklung in Forschung, Studium und Administration Y1 - 2017 SN - 1860-3041 N1 - gedruckt in der Bereichsbibliothek Eupener Str. vorhanden VL - 11 IS - 1 SP - 17 EP - 24 PB - UVW Universitäts-Verlag Webler CY - Bielefeld ER - TY - JOUR A1 - Funke, Harald A1 - Keinz, Jan A1 - Kusterer, K. A1 - Haj Ayed, A. A1 - Kazari, M. A1 - Kitajima, J. A1 - Horikawa, A. A1 - Okada, K. T1 - Development and Testing of a Low NOX Micromix Combustion Chamber for an Industrial Gas Turbine JF - International Journal of Gas Turbine, Propulsion and Power Systems N2 - The Micromix combustion principle, based on cross-flow mixing of air and hydrogen, promises low emission applications in future gas turbines. The Micromix combustion takes place in several hundreds of miniaturized diffusion-type micro-flames. The major advantage is the inherent safety against flash-back and low NOx-emissions due to a very short residence time of reactants in the flame region. The paper gives insight into the Micromix design and scaling procedure for different energy densities and the interaction of scaling laws and key design drivers in gas turbine integration. Numerical studies, experimental testing, gas turbine integration and interface considerations are evaluated. The aerodynamic stabilization of the miniaturized flamelets and the resulting flow field, flame structure and NOx formation are analysed experimentally and numerically. The results show and confirm the successful adaption of the low NOx Micromix characteristics for a range of different nozzle sizes, energy densities and thermal power output. Y1 - 2017 U6 - https://doi.org/10.38036/jgpp.9.1_27 SN - 1882-5079 VL - 9 IS - 1 SP - 27 EP - 36 ER - TY - JOUR A1 - Funke, Harald A1 - Beckmann, Nils A1 - Keinz, Jan A1 - Abanteriba, Sylvester T1 - Numerical and Experimental Evaluation of a Dual-Fuel Dry-Low-NOx Micromix Combustor for Industrial Gas Turbine Applications JF - Journal of Thermal Science and Engineering Applications Y1 - 2019 U6 - https://doi.org/10.1115/1.4041495 SN - 19485085 N1 - Paper No: GT2017-64795 VL - 11 IS - 1 SP - 011015 PB - ASME CY - New York ER - TY - JOUR A1 - Schael, S. A1 - Atanasyan, A. A1 - Berdugo, J. A1 - Bretz, T. A1 - Czupalla, Markus A1 - Dachwald, Bernd A1 - Doetinchem, P. von A1 - Duranti, M. A1 - Gast, H. A1 - Karpinski, W. A1 - Kirn, T. A1 - Lübelsmeyer, K. A1 - Maña, C. A1 - Marrocchesi, P.S. A1 - Mertsch, P. A1 - Moskalenko, I.V. A1 - Schervan, T. A1 - Schluse, M. A1 - Schröder, K.-U. A1 - Schultz von Dratzig, A. A1 - Senatore, C. A1 - Spies, L. A1 - Wakely, S.P. A1 - Wlochal, M. A1 - Uglietti, D. A1 - Zimmermann, J. T1 - AMS-100: The next generation magnetic spectrometer in space – An international science platform for physics and astrophysics at Lagrange point 2 JF - Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment Y1 - 2019 U6 - https://doi.org/10.1016/j.nima.2019.162561 SN - 0168-9002 VL - 944 IS - 162561 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Finger, Felix A1 - Götten, Falk A1 - Braun, Carsten A1 - Bil, Cees T1 - Mass, primary energy, and cost: the impact of optimization objectives on the initial sizing of hybrid-electric general aviation aircraft JF - CEAS Aeronautical Journal N2 - For short take-off and landing (STOL) aircraft, a parallel hybrid-electric propulsion system potentially offers superior performance compared to a conventional propulsion system, because the short-take-off power requirement is much higher than the cruise power requirement. This power-matching problem can be solved with a balanced hybrid propulsion system. However, there is a trade-off between wing loading, power loading, the level of hybridization, as well as range and take-off distance. An optimization method can vary design variables in such a way that a minimum of a particular objective is attained. In this paper, a comparison between the optimization results for minimum mass, minimum consumed primary energy, and minimum cost is conducted. A new initial sizing algorithm for general aviation aircraft with hybrid-electric propulsion systems is applied. This initial sizing methodology covers point performance, mission performance analysis, the weight estimation process, and cost estimation. The methodology is applied to the design of a STOL general aviation aircraft, intended for on-demand air mobility operations. The aircraft is sized to carry eight passengers over a distance of 500 km, while able to take off and land from short airstrips. Results indicate that parallel hybrid-electric propulsion systems must be considered for future STOL aircraft. Y1 - 2020 U6 - https://doi.org/10.1007/s13272-020-00449-8 SN - 1869-5590 N1 - Corresponding author: Felix Finger VL - 2020 IS - 11 SP - 713 EP - 730 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Finger, Felix A1 - Braun, Carsten A1 - Bil, Cees T1 - Impact of Battery Performance on the Initial Sizing of Hybrid-Electric General Aviation Aircraft JF - Journal of Aerospace Engineering N2 - Studies suggest that hybrid-electric aircraft have the potential to generate fewer emissions and be inherently quieter when compared to conventional aircraft. By operating combustion engines together with an electric propulsion system, synergistic benefits can be obtained. However, the performance of hybrid-electric aircraft is still constrained by a battery’s energy density and discharge rate. In this paper, the influence of battery performance on the gross mass for a four-seat general aviation aircraft with a hybrid-electric propulsion system is analyzed. For this design study, a high-level approach is chosen, using an innovative initial sizing methodology to determine the minimum required aircraft mass for a specific set of requirements and constraints. Only the peak-load shaving operational strategy is analyzed. Both parallel- and serial-hybrid propulsion configurations are considered for two different missions. The specific energy of the battery pack is varied from 200 to 1,000 W⋅h/kg, while the discharge time, and thus the normalized discharge rating (C-rating), is varied between 30 min (2C discharge rate) and 2 min (30C discharge rate). With the peak-load shaving operating strategy, it is desirable for hybrid-electric aircraft to use a light, low capacity battery system to boost performance. For this case, the battery’s specific power rating proved to be of much higher importance than for full electric designs, which have high capacity batteries. Discharge ratings of 20C allow a significant take-off mass reduction aircraft. The design point moves to higher wing loadings and higher levels of hybridization if batteries with advanced technology are used. Y1 - 2020 U6 - https://doi.org/10.1061/(ASCE)AS.1943-5525.0001113 SN - 1943-5525 VL - 33 IS - 3 PB - ASCE CY - Reston, Va. ER - TY - JOUR A1 - Khayyam, Hamid A1 - Jamali, Ali A1 - Bab-Hadiashar, Alireza A1 - Esch, Thomas A1 - Ramakrishna, Seeram A1 - Jalil, Mahdi A1 - Naebe, Minoo T1 - A Novel Hybrid Machine Learning Algorithm for Limited and Big Data Modelling with Application in Industry 4.0 JF - IEEE Access N2 - To meet the challenges of manufacturing smart products, the manufacturing plants have been radically changed to become smart factories underpinned by industry 4.0 technologies. The transformation is assisted by employment of machine learning techniques that can deal with modeling both big or limited data. This manuscript reviews these concepts and present a case study that demonstrates the use of a novel intelligent hybrid algorithms for Industry 4.0 applications with limited data. In particular, an intelligent algorithm is proposed for robust data modeling of nonlinear systems based on input-output data. In our approach, a novel hybrid data-driven combining the Group-Method of Data-Handling and Singular-Value Decomposition is adapted to find an offline deterministic model combined with Pareto multi-objective optimization to overcome the overfitting issue. An Unscented-Kalman-Filter is also incorporated to update the coefficient of the deterministic model and increase its robustness against data uncertainties. The effectiveness of the proposed method is examined on a set of real industrial measurements. Y1 - 2020 SN - 2169-3536 U6 - https://doi.org/10.1109/ACCESS.2020.2999898 SP - 1 EP - 12 PB - IEEE CY - New York, NY ER - TY - JOUR A1 - Hailer, Benjamin A1 - Weber, Tobias A1 - Neveling, Sebastian A1 - Dera, Samuel A1 - Arent, Jan-Christoph A1 - Middendorf, Peter T1 - Development of a test device to determine the frictional behavior between honeycomb and prepreg layers under realistic manufacturing conditions JF - Journal of Sandwich Structures & Materials N2 - In the friction tests between honeycomb with film adhesive and prepreg, the relative displacement occurs between the film adhesive and the prepreg. The film adhesive does not shift relative to the honeycomb. This is consistent with the core crush behavior where the honeycomb moves together with the film adhesive, as can be seen in Figure 2(a). The pull-through forces of the friction measurements between honeycomb and prepreg at 1 mm deformation are plotted in Figure 17(a). While the friction at 100°C is similar to the friction at 120°C, it decreases significantly at 130°C and exhibits a minimum at 140°C. At 150°C, the friction rises again slightly and then sharply at 160°C. Since the viscosity of the M18/1 prepreg resin drops significantly before it cures [23], the minimum friction at 140°C could result from a minimum viscosity of the mixture of prepreg resin and film adhesive before the bond subsequently cures. Figure 17(b) shows the mean value curve of the friction measurements at 140°C. The error bars, which represent the standard deviation, reveal the good repeatability of the tests. The force curve is approximately horizontal between 1 mm and 2 mm. The friction then slightly rises. As with interlaminar friction measurements, this could be due to the fact that resin is removed by friction and the proportion of boundary lubrication increases. Figure 18 shows the surfaces after the friction measurement. The honeycomb cell walls are clearly visible in the film adhesive. There are areas where the film adhesive is completely removed and the carrier material of the film adhesive becomes visible. In addition, the viscosity of the resin changes as the curing progresses during the friction test. This can also affect the force-displacement curve. Y1 - 2020 U6 - https://doi.org/10.1177/1099636220923986 SN - 1530-7972 IS - Volume 23, Issue 7 SP - 3017 EP - 3043 PB - Sage CY - London 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 - https://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 - 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 - https://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 - Götten, Falk A1 - Finger, Felix A1 - Havermann, Marc A1 - Braun, Carsten A1 - Gomez, Francisco A1 - Bill, C. T1 - On the flight performance impact of landing gear drag reduction methods for unmanned air vehicles JF - Deutscher Luft- und Raumfahrtkongress 2018 N2 - The flight performance impact of three different landing gear configurations on a small, fixed-wing UAV is analyzed with a combination of RANS CFD calculations and an incremental flight performance algorithm. A standard fixed landing gear configuration is taken as a baseline, while the influence of retracting the landing gear or applying streamlined fairings is investigated. A retraction leads to a significant parasite drag reduction, while also fairings promise large savings. The increase in lift-to-drag ratio is reduced at high lift coefficients due to the influence of induced drag. All configurations are tested on three different design missions with an incremental flight performance algorithm. A trade-off study is performed using the retracted or faired landing gear's weight increase as a variable. The analysis reveals only small mission performance gains as the aerodynamic improvements are negated by weight penalties. A new workflow for decision-making is presented that allows to estimate if a change in landing gear configuration is beneficial for a small UAV. Y1 - 2018 U6 - https://doi.org/10.25967/480058 PB - DGLR CY - Bonn ER - TY - JOUR A1 - Tekin, Nurettin A1 - Ashikaga, Mitsugu A1 - Horikawa, Atsushi A1 - Funke, Harald T1 - Enhancement of fuel flexibility of industrial gas turbines by development of innovative hydrogen combustion systems JF - Gas for energy N2 - For fuel flexibility enhancement hydrogen represents a possible alternative gas turbine fuel within future low emission power generation, in case of hydrogen production by the use of renewable energy sources such as wind energy or biomass. Kawasaki Heavy Industries, Ltd. (KHI) has research and development projects for future hydrogen society; production of hydrogen gas, refinement and liquefaction for transportation and storage, and utilization with gas turbine / gas engine for the generation of electricity. In the development of hydrogen gas turbines, a key technology is the stable and low NOx hydrogen combustion, especially Dry Low Emission (DLE) or Dry Low NOx (DLN) hydrogen combustion. Due to the large difference in the physical properties of hydrogen compared to other fuels such as natural gas, well established gas turbine combustion systems cannot be directly applied for DLE hydrogen combustion. Thus, the development of DLE hydrogen combustion technologies is an essential and challenging task for the future of hydrogen fueled gas turbines. The DLE Micro-Mix combustion principle for hydrogen fuel has been in development for many years to significantly reduce NOx emissions. This combustion principle is based on cross-flow mixing of air and gaseous hydrogen which reacts in multiple miniaturized “diffusion-type” flames. The major advantages of this combustion principle are the inherent safety against flashback and the low NOx-emissions due to a very short residence time of the reactants in the flame region of the micro-flames. Y1 - 2018 IS - 2 PB - Vulkan-Verlag CY - Essen ER - TY - JOUR A1 - Thoma, Andreas A1 - Ravi, Sridhar T1 - Significance of parallel computing on the performance of Digital Image Correlation algorithms in MATLAB N2 - Digital Image Correlation (DIC) is a powerful tool used to evaluate displacements and deformations in a non-intrusive manner. By comparing two images, one of the undeformed reference state of a specimen and another of the deformed target state, the relative displacement between those two states is determined. DIC is well known and often used for post-processing analysis of in-plane displacements and deformation of specimen. Increasing the analysis speed to enable real-time DIC analysis will be beneficial and extend the field of use of this technique. Here we tested several combinations of the most common DIC methods in combination with different parallelization approaches in MATLAB and evaluated their performance to determine whether real-time analysis is possible with these methods. To reflect improvements in computing technology different hardware settings were also analysed. We found that implementation problems can reduce the efficiency of a theoretically superior algorithm such that it becomes practically slower than a suboptimal algorithm. The Newton-Raphson algorithm in combination with a modified Particle Swarm algorithm in parallel image computation was found to be most effective. This is contrary to theory, suggesting that the inverse-compositional Gauss-Newton algorithm is superior. As expected, the Brute Force Search algorithm is the least effective method. We also found that the correct choice of parallelization tasks is crucial to achieve improvements in computing speed. A poorly chosen parallelisation approach with high parallel overhead leads to inferior performance. Finally, irrespective of the computing mode the correct choice of combinations of integerpixel and sub-pixel search algorithms is decisive for an efficient analysis. Using currently available hardware realtime analysis at high framerates remains an aspiration. Y1 - 2019 SP - 1 EP - 17 ER - TY - JOUR A1 - Schildt, Ph. A1 - Braun, Carsten A1 - Marzocca, P. T1 - Metric evaluating potentials of condition-monitoring approaches for hybrid electric aircraft propulsion systems JF - CEAS Aeronautical Journal Y1 - 2019 U6 - https://doi.org/10.1007/s13272-019-00411-3 SN - 1869-5590 SP - 1 EP - 14 PB - Springer CY - Berlin ER - TY - JOUR A1 - Götten, Falk A1 - Havermann, Marc A1 - Braun, Carsten A1 - Gomez, Francisco A1 - Bil, Cees T1 - RANS Simulation Validation of a Small Sensor Turret for UAVs JF - Journal of Aerospace Engineering N2 - Recent Unmanned Aerial Vehicle (UAV) design procedures rely on full aircraft steady-state Reynolds-Averaged-Navier-Stokes (RANS) analyses in early design stages. Small sensor turrets are included in such simulations, even though their aerodynamic properties show highly unsteady behavior. Very little is known about the effects of this approach on the simulation outcomes of small turrets. Therefore, the flow around a model turret at a Reynolds number of 47,400 is simulated with a steady-state RANS approach and compared to experimental data. Lift, drag, and surface pressure show good agreement with the experiment. The RANS model predicts the separation location too far downstream and shows a larger recirculation region aft of the body. Both characteristic arch and horseshoe vortex structures are visualized and qualitatively match the ones found by the experiment. The Reynolds number dependence of the drag coefficient follows the trend of a sphere within a distinct range. The outcomes indicate that a steady-state RANS model of a small sensor turret is able to give results that are useful for UAV engineering purposes but might not be suited for detailed insight into flow properties. Y1 - 2019 U6 - https://doi.org/10.1061/(ASCE)AS.1943-5525.0001055 SN - 1943-5525 VL - 32 IS - 5 PB - ASCE CY - New York ER - TY - JOUR A1 - Dachwald, Bernd A1 - Ulamec, Stephan A1 - Postberg, Frank A1 - Sohl, Frank A1 - Vera, Jean-Pierre de A1 - Christoph, Waldmann A1 - Lorenz, Ralph D. A1 - Hellard, Hugo A1 - Biele, Jens A1 - Rettberg, Petra T1 - Key technologies and instrumentation for subsurface exploration of ocean worlds JF - Space Science Reviews N2 - In this chapter, the key technologies and the instrumentation required for the subsurface exploration of ocean worlds are discussed. The focus is laid on Jupiter’s moon Europa and Saturn’s moon Enceladus because they have the highest potential for such missions in the near future. The exploration of their oceans requires landing on the surface, penetrating the thick ice shell with an ice-penetrating probe, and probably diving with an underwater vehicle through dozens of kilometers of water to the ocean floor, to have the chance to find life, if it exists. Technologically, such missions are extremely challenging. The required key technologies include power generation, communications, pressure resistance, radiation hardness, corrosion protection, navigation, miniaturization, autonomy, and sterilization and cleaning. Simpler mission concepts involve impactors and penetrators or – in the case of Enceladus – plume-fly-through missions. Y1 - 2020 U6 - https://doi.org/10.1007/s11214-020-00707-5 SN - 1572-9672 N1 - Corresponding author: Bernd Dachwald VL - 216 IS - Art. 83 PB - Springer CY - Dordrecht ER -