@article{FunkeBoernerKrebsetal.2011, author = {Funke, Harald and B{\"o}rner, Sebastian and Krebs, W. and Wolf, E.}, title = {Experimental Characterization of Low NOx Micromix Prototype Combustors for Industrial Gas Turbine Applications}, series = {ASME Turbo Expo 2011 ; Vancouver, Canada, June 6-10, 2011}, journal = {ASME Turbo Expo 2011 ; Vancouver, Canada, June 6-10, 2011}, year = {2011}, language = {en} } @article{RobinsonFunkeHendrick2011, author = {Robinson, A. E. and Funke, Harald and Hendrick, P.}, title = {Design and Testing of a Micromix Combustor With Recuperative Wall Cooling for a Hydrogen Fueled µ-Scale Gas Turbine}, series = {Journal of engineering for gas turbines and power}, volume = {133}, journal = {Journal of engineering for gas turbines and power}, number = {8}, publisher = {ASME}, address = {New York}, isbn = {1528-8919}, pages = {Art. Nr. 082301 , 8 Seiten}, year = {2011}, language = {en} } @article{HavermannKainumaTakayama2005, author = {Havermann, Marc and Kainuma, M. and Takayama, K.}, title = {Influence of Physical and Geometrical Parameters on Vortex Rings Generated by a Shock Tube / Havermann, M. ; Kainuma, M. ; Takayama, K.}, series = {Non-lethal options enhancing security and stability : 3rd European Symposium on Non-Lethal Weapons, May 10 - 12, 2005, Ettlingen, Germany / ICT, Fraunhofer-Institut Chemische Technologie; European Working Group Non-Lethal Weapons}, journal = {Non-lethal options enhancing security and stability : 3rd European Symposium on Non-Lethal Weapons, May 10 - 12, 2005, Ettlingen, Germany / ICT, Fraunhofer-Institut Chemische Technologie; European Working Group Non-Lethal Weapons}, publisher = {ICT}, address = {Pfinztal}, pages = {getr. Z{\"a}hlung [ca. 600 S.]}, year = {2005}, language = {en} } @article{HavermannMoeglin2005, author = {Havermann, Marc and Moeglin, J.-P.}, title = {ISL's Research on Systems with Controlled Effects for Non-Lethal Applications / Moeglin, J.-P. ; Havermann, M. et al.}, series = {Non-lethal options enhancing security and stability : 3rd European Symposium on Non-Lethal Weapons, May 10 - 12, 2005, Ettlingen, Germany / ICT, Fraunhofer-Institut Chemische Technologie; European Working Group Non-Lethal Weapons}, journal = {Non-lethal options enhancing security and stability : 3rd European Symposium on Non-Lethal Weapons, May 10 - 12, 2005, Ettlingen, Germany / ICT, Fraunhofer-Institut Chemische Technologie; European Working Group Non-Lethal Weapons}, publisher = {ICT}, address = {Pfinztal}, pages = {getr. Z{\"a}hlung [ca. 600 S.]}, year = {2005}, language = {en} } @article{HavermannHaertigReyetal.2001, author = {Havermann, Marc and Haertig, J. and Rey, C. and George, F.}, title = {PIV measurements in Mach 3.5 and 4.5 shock tunnel flow / Haertig, J. ; Havermann, M. ; Rey, C. ; George, F.}, publisher = {-}, year = {2001}, language = {en} } @article{Havermann2006, author = {Havermann, Marc}, title = {Systematic Shock Tube Experiments on Vortex Ring Generation and Propagation / Havermann, M. ; Kainuma, M. ; Takayama, K.}, series = {Shock waves : proceedings of the 25th International Symposium on Shock Waves-ISSW25, July 17 - 22, 2005, Bangalore, India / ed.: G. Jagadeesh}, journal = {Shock waves : proceedings of the 25th International Symposium on Shock Waves-ISSW25, July 17 - 22, 2005, Bangalore, India / ed.: G. Jagadeesh}, publisher = {Universities Pr.}, address = {Hyderabad}, isbn = {978-81-7371571-6}, pages = {1141 S.}, year = {2006}, language = {en} } @article{FunkeRobinson2007, author = {Funke, Harald and Robinson, A. E.}, title = {Development of a new test rig for a micro scale hydrogen combustion chamber}, series = {Proceedings of the 2nd European Conference for Aero-Space Sciences : July 1 - 6, 2007, Brussels, Belgium}, journal = {Proceedings of the 2nd European Conference for Aero-Space Sciences : July 1 - 6, 2007, Brussels, Belgium}, publisher = {-}, pages = {1 -- 8}, year = {2007}, language = {en} } @article{HavermannSeiler2006, author = {Havermann, Marc and Seiler, F.}, title = {Boundary Layer Influence on Supersonic Jet/Cross-Flow Interaction in Hypersonic Flow / Havermann, M. ; Seiler, F.}, series = {Notes on Numerical Fluid Mechanics and Multidisciplinary Design. 92 (2006)}, journal = {Notes on Numerical Fluid Mechanics and Multidisciplinary Design. 92 (2006)}, publisher = {-}, isbn = {1612-2909}, pages = {281 -- 288}, year = {2006}, language = {en} } @article{HavermannHaertigReyetal.2002, author = {Havermann, Marc and Haertig, J. and Rey, C. and George, A.}, title = {Particle image velocimetry in mach 3.5 and 4.5 shock-tunnel flows / Haertig, J. ; Havermann, M. ; Rey, C. ; George, A.}, series = {AIAA journal. 40 (2002), H. 6}, journal = {AIAA journal. 40 (2002), H. 6}, publisher = {-}, isbn = {0001-1452}, pages = {1056 -- 1060}, year = {2002}, language = {en} } @article{HavermannHaertigReyetal.2008, author = {Havermann, Marc and Haertig, J. and Rey, C. and George, A.}, title = {PIV Measurements in Shock Tunnels and Shock Tubes / Havermann, M. ; Haertig, J. ; Rey, C. ; George, A.}, series = {Particle Image Velocimetry : New Developments and Recent Applications}, journal = {Particle Image Velocimetry : New Developments and Recent Applications}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-540-73528-1}, pages = {429 -- 442}, year = {2008}, language = {en} } @article{HavermannSeilerGeorgesetal.2008, author = {Havermann, Marc and Seiler, F. and Georges, A. and Srulijes, J.}, title = {Progress in Doppler picture velocimetry (DPV) / Seiler, F. ; George, A. ; Srulijes, J. ; Havermann, M.}, series = {Experiments in Fluids. 44 (2008), H. 3}, journal = {Experiments in Fluids. 44 (2008), H. 3}, publisher = {-}, isbn = {1432-1114}, pages = {389 -- 395}, year = {2008}, language = {en} } @article{PichlerGeorgeSeileretal.2009, author = {Pichler, A. and George, A. and Seiler, F. and Srulijes, J. and Havermann, Marc}, title = {Doppler Picture Velocimetry (DPV) applied to hypersonics}, series = {Shock Waves [Elektronische Ressource] : 26th International Symposium on Shock Waves, Volume 1 / edited by Klaus Hannemann, Friedrich Seiler}, journal = {Shock Waves [Elektronische Ressource] : 26th International Symposium on Shock Waves, Volume 1 / edited by Klaus Hannemann, Friedrich Seiler}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-540-85168-4}, pages = {503 -- 508}, year = {2009}, language = {en} } @article{HavermannSeilerGeorgeetal.2003, author = {Havermann, Marc and Seiler, F. and George, A. and Leopold, F.}, title = {Planar Velocity Visualization in High-Speed Wedge Flow using Doppler Picture Velocimetry (DPV) compared with Particle Image Velocimetry (PIV) / Seiler, F. ; Havermann, M. ; George, A. ; Leopold, F. ; Srulijes, J.}, series = {Journal of Visualization. 6 (2003), H. 3}, journal = {Journal of Visualization. 6 (2003), H. 3}, publisher = {-}, isbn = {1343-8875}, pages = {253 -- 262}, year = {2003}, language = {en} } @article{HavermannBeylich1997, author = {Havermann, Marc and Beylich, A. E.}, title = {Performance and Limitations of the Laser-Induced Fluorescence Measurement Technique and the Established Experimental Methods for the Study of Supersonic Mixing / Havermann, M. ; Beylich, A. E.}, series = {International Journal of heat and technology. 15 (1997), H. 2}, journal = {International Journal of heat and technology. 15 (1997), H. 2}, publisher = {-}, pages = {3 -- 10}, year = {1997}, language = {en} } @article{Havermann2005, author = {Havermann, Marc}, title = {Effects of the shock tube open-end shape on vortex loops released from it / Kainuma, M. ; Havermann, M. ; Sun, M. ; Takayama, K.}, series = {Shock Waves : Proceedings of the 24th International Symposium on Shock Waves Beijing, China July 11-16, 2004 / edited by Z. Jiang}, journal = {Shock Waves : Proceedings of the 24th International Symposium on Shock Waves Beijing, China July 11-16, 2004 / edited by Z. Jiang}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-540-22497-6}, pages = {505 -- 510}, year = {2005}, language = {en} } @article{HavermannSeilerBolleretal.2005, author = {Havermann, Marc and Seiler, F. and Boller, F. and Mangold, P.}, title = {Operation of the ISL transonic shock tube in a high subsonic flow regime / Seiler, F. ; Havermann, M. ; Boller, F. ; Mangold, P. ; Takayama K.}, series = {Shock Waves : Proceedings of the 24th International Symposium on Shock Waves Beijing, China July 11-16, 2004 / edited by Z. Jiang}, journal = {Shock Waves : Proceedings of the 24th International Symposium on Shock Waves Beijing, China July 11-16, 2004 / edited by Z. Jiang}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-540-22497-6}, pages = {307 -- 312}, year = {2005}, language = {en} } @article{HavermannEndeSeileretal.2005, author = {Havermann, Marc and Ende, H. and Seiler, F. and Schwenzer, M.}, title = {Shock tunnel measurement of the interaction amplification factor for a hot gas side jet in a supersonic cross flow / Havermann, M. ; Ende, H. ; Seiler, F. ; Schwenzer, M.}, series = {Shock Waves : Proceedings of the 24th International Symposium on Shock Waves Beijing, China July 11-16, 2004 / edited by Z. Jiang}, journal = {Shock Waves : Proceedings of the 24th International Symposium on Shock Waves Beijing, China July 11-16, 2004 / edited by Z. Jiang}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-540-22497-6}, pages = {113 -- 118}, year = {2005}, language = {en} } @article{KowalskiMcElwaine2013, author = {Kowalski, Julia and McElwaine, Jim N.}, title = {Shallow two-component gravity-driven flows with vertical variation}, series = {Journal of Fluid Mechanics}, volume = {714}, journal = {Journal of Fluid Mechanics}, publisher = {Cambridge Univ. Press}, address = {Cambridge}, isbn = {0022-1120}, pages = {434 -- 462}, year = {2013}, language = {en} } @article{OlaruKowalskiSethietal.2012, author = {Olaru, Alexandra Maria and Kowalski, Julia and Sethi, Vaishali and Bl{\"u}mich, Bernhard}, title = {Exchange relaxometry of flow at small P{\´e}clet numbers in a glass bead pack}, series = {Journal of Magnetic Resonance (JMR)}, volume = {220}, journal = {Journal of Magnetic Resonance (JMR)}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1096-0856}, doi = {10.1016/j.jmr.2012.04.015}, pages = {32 -- 44}, year = {2012}, abstract = {In this paper we consider low P{\´e}clet 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.}, language = {en} } @article{FischerKowalskiPudasaini2012, author = {Fischer, Jan-Thomas and Kowalski, Julia and Pudasaini, Shiva P.}, title = {Topographic curvature effects in applied avalanche modelling}, series = {Cold Regions Science and Technology}, volume = {74-75}, journal = {Cold Regions Science and Technology}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1872-7441}, doi = {10.1016/j.coldregions.2012.01.005}, pages = {21 -- 30}, year = {2012}, abstract = {This paper describes the implementation of topographic curvature effects within the RApid Mass MovementS (RAMMS) snow avalanche simulation toolbox. RAMMS is based on a model similar to shallow water equations with a Coulomb friction relation and the velocity dependent Voellmy drag. It is used for snow avalanche risk assessment in Switzerland. The snow avalanche simulation relies on back calculation of observed avalanches. The calibration of the friction parameters depends on characteristics of the avalanche track. The topographic curvature terms are not yet included in the above mentioned classical model. Here, we fundamentally improve this model by mathematically and physically including the topographic curvature effects. By decomposing the velocity dependent friction into a topography dependent term that accounts for a curvature enhancement in the Coulomb friction, and a topography independent contribution similar to the classical Voellmy drag, we construct a general curvature dependent frictional resistance, and thus propose new extended model equations. With three site-specific examples, we compare the apparent frictional resistance of the new approach, which includes topographic curvature effects, to the classical one. Our simulation results demonstrate substantial effects of the curvature on the flow dynamics e.g., the dynamic pressure distribution along the slope. The comparison of resistance coefficients between the two models demonstrates that the physically based extension presents an improvement to the classical approach. Furthermore a practical example highlights its influence on the pressure outline in the run out zone of the avalanche. Snow avalanche dynamics modeling natural terrain curvature centrifugal force friction coefficients.}, language = {en} } @article{BuehlerChristenKowalskietal.2011, author = {B{\"u}hler, Yves and Christen, Marc and Kowalski, Julia and Bartelt, Perry}, title = {Sensitivity of snow avalanche simulations to digital elevation model quality and resolution}, series = {Annals of Glaciology}, volume = {52}, journal = {Annals of Glaciology}, number = {58}, publisher = {Cambridge University Press}, address = {Cambridge}, isbn = {1727-5644}, pages = {72 -- 80}, year = {2011}, abstract = {Digital elevation models (DEMs), represent the three-dimensional terrain and are the basic input for numerical snow avalanche dynamics simulations. DEMs can be acquired using topographic maps or remote-sensing technologies, such as photogrammetry or lidar. Depending on the acquisition technique, different spatial resolutions and qualities are achieved. However, there is a lack of studies that investigate the sensitivity of snow avalanche simulation algorithms to the quality and resolution of DEMs. Here, we perform calculations using the numerical avalance dynamics model RAMMS, varying the quality and spatial resolution of the underlying DEMs, while holding the simulation parameters constant. We study both channelized and open-terrain avalanche tracks with variable roughness. To quantify the variance of these simulations, we use well-documented large-scale avalanche events from Davos, Switzerland (winter 2007/08), and from our large-scale avalanche test site, Valĺee de la Sionne (winter 2005/06). We find that the DEM resolution and quality is critical for modeled flow paths, run-out distances, deposits, velocities and impact pressures. Although a spatial resolution of ~25 m is sufficient for large-scale avalanche modeling, the DEM datasets must be checked carefully for anomalies and artifacts before using them for dynamics calculations.}, language = {en} } @article{ChristenBarteltKowalski2010, author = {Christen, Marc and Bartelt, Perry and Kowalski, Julia}, title = {Back calculation of the In den Arelen avalanche with RAMMS: Interpretation of model results}, series = {Annals of Glaciology}, volume = {51}, journal = {Annals of Glaciology}, number = {54}, publisher = {Cambridge University Press}, address = {Cambridge}, isbn = {1727-5644}, doi = {10.3189/172756410791386553}, pages = {161 -- 168}, year = {2010}, abstract = {Two- and three-dimensional avalanche dynamics models are being increasingly used in hazard-mitigation studies. These models can provide improved and more accurate results for hazard mapping than the simple one-dimensional models presently used in practice. However, two- and three-dimensional models generate an extensive amount of output data, making the interpretation of simulation results more difficult. To perform a simulation in three-dimensional terrain, numerical models require a digital elevation model, specification of avalanche release areas (spatial extent and volume), selection of solution methods, finding an adequate calculation resolution and, finally, the choice of friction parameters. In this paper, the importance and difficulty of correctly setting up and analysing the results of a numerical avalanche dynamics simulation is discussed. We apply the two-dimensional simulation program RAMMS to the 1968 extreme avalanche event In den Arelen. We show the effect of model input variations on simulation results and the dangers and complexities in their interpretation.}, language = {en} } @article{FischerKowalskiPudasainietal.2009, author = {Fischer, Jan-Thomas and Kowalski, Julia and Pudasaini, Shiva P. and Miller, S. A.}, title = {Dynamic Avalanche Modeling in Natural Terrain}, series = {International Snow Science Workshop, Davos 2009, Proceedings ; Proc. ISSW 2009}, journal = {International Snow Science Workshop, Davos 2009, Proceedings ; Proc. ISSW 2009}, pages = {448 -- 452}, year = {2009}, abstract = {The powerful avalanche simulation toolbox RAMMS (Rapid Mass Movements) is based on a depth-averaged hydrodynamic system of equations with a Voellmy-Salm friction relation. The two empirical friction parameters μ and � correspond to a dry Coulomb friction and a viscous resistance, respectively. Although μ and � lack a proper physical explanation, 60 years of acquired avalanche data in the Swiss Alps made a systematic calibration possible. RAMMS can therefore successfully model avalanche flow depth, velocities, impact pressure and run out distances. Pudasaini and Hutter (2003) have proposed extended, rigorously derived model equations that account for local curvature and twist. A coordinate transformation into a reference system, applied to the actual mountain topography of the natural avalanche path, is performed. The local curvature and the twist of the avalanche path induce an additional term in the overburden pressure. This leads to a modification of the Coulomb friction, the free-surface pressure gradient, the pressure induced by the channel, and the gravity components along and normal to the curved and twisted reference surface. This eventually guides the flow dynamics and deposits of avalanches. In the present study, we investigate the influence of curvature on avalanche flow in real mountain terrain. Simulations of real avalanche paths are performed and compared for the different models approaches. An algorithm to calculate curvature in real terrain is introduced in RAMMS. This leads to a curvature dependent friction relation in an extended version of the Voellmy-Salm model equations. Our analysis provides yet another step in interpreting the physical meaning and significance of the friction parameters used in the RAMMS computational environment.}, language = {en} } @article{McArdellBarteltKowalski2007, author = {McArdell, Brian W. and Bartelt, Perry and Kowalski, Julia}, title = {Field observations of basal forces and fluid pore pressure in a debris flow}, series = {Geophysical Research Letters (GRL)}, volume = {34}, journal = {Geophysical Research Letters (GRL)}, number = {7}, isbn = {0094-8276}, year = {2007}, abstract = {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.}, language = {en} } @article{HeierliPurvesFelberetal.2004, author = {Heierli, Joachim and Purves, Ross S. and Felber, Andreas and Kowalski, Julia}, title = {Verification of nearest-neighbours interpretations in avalanche forecasting}, series = {Annals of Glaciology}, volume = {38}, journal = {Annals of Glaciology}, number = {1}, isbn = {1727-5644}, pages = {84 -- 88}, year = {2004}, abstract = {This paper examines the positive and negative aspects of a range of interpretations of nearest-neighbours models. Measures-oriented and distributionoriented verification methods are applied to categorial, probabilistic and descriptive interpretations of nearest neighbours used operationally in avalanche forecasting in Scotland and Switzerland. The dependence of skill and accuracy measures on base rate is illustrated. The purpose of the forecast and the definition of events are important variables in determining the quality of the forecast. A discussion of the application of different interpretations in operational avalanche forecasting is presented.}, language = {en} } @article{MertensKlevenhusenJakob1987, author = {Mertens, Josef and Klevenhusen, K. D. and Jakob, H.}, title = {Accurate Transonic Wave Drag Prediction Using Simple Physical Models}, series = {AIAA-Journal. 25 (1987), H. 6}, journal = {AIAA-Journal. 25 (1987), H. 6}, isbn = {0001-1452}, pages = {799 -- 805}, year = {1987}, language = {en} } @article{MertensHenke2001, author = {Mertens, Josef and Henke, Rolf}, title = {Adaptive technologies for future civil air transport}, series = {Air \& Space Europe. 3 (2001), H. 3-4}, journal = {Air \& Space Europe. 3 (2001), H. 3-4}, isbn = {1247-5793}, pages = {80 -- 82}, year = {2001}, language = {en} } @article{Mertens1998, author = {Mertens, Josef}, title = {Required technologies for supersonic aircraft}, series = {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}, journal = {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}, publisher = {Research and Technology Organization}, address = {Neuilly-sur-Seine}, isbn = {92-837-1007-X}, pages = {5.1 -- 5.16}, year = {1998}, language = {en} } @article{Mertens1998, author = {Mertens, Josef}, title = {Multi point design challenges for supersonic transports}, series = {Fluid dynamics research on supersonic aircraft : this report is a compilation of the edited proceedings of the special course on "Fluid dynamics research on supersonic aircraft" held at the Karman Institute for Fluid Dynamics (VKI) in Rhode-Saint-Genese, Belgium, 25-29 May 1998}, journal = {Fluid dynamics research on supersonic aircraft : this report is a compilation of the edited proceedings of the special course on "Fluid dynamics research on supersonic aircraft" held at the Karman Institute for Fluid Dynamics (VKI) in Rhode-Saint-Genese, Belgium, 25-29 May 1998}, publisher = {Research and Technology Organization}, address = {Neuilly-sur-Seine}, isbn = {92-837-1007-X}, pages = {8.1 -- 8.12}, year = {1998}, language = {en} } @article{OverduinBlomeHoell2007, author = {Overduin, James and Blome, Hans-Joachim and Hoell, Josef}, title = {Wolfgang Priester: from the big bounce to the Lambda-dominated universe}, series = {Naturwissenschaften}, volume = {94}, journal = {Naturwissenschaften}, number = {6}, isbn = {0028-1042}, pages = {417 -- 429}, year = {2007}, language = {en} } @article{TrillaGrossenRobinsonetal.2008, author = {Trilla, Joan and Grossen, J{\"u}rgen and Robinson, Alexander and Funke, Harald and Bosschaerts, Walter and Hendrick, Patrick}, title = {Development of a hydrogen combustion chamber for an ultra micro gas turbine}, series = {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}, journal = {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}, pages = {101 -- 104}, year = {2008}, language = {en} } @article{RobinsonFunkeHendricketal.2008, author = {Robinson, A. E. and Funke, Harald and Hendrick, P. and Recker, E. and Peirs, J.}, title = {Development of a hydrogen fuelled 1 kW ultra micro gas turbine with special respect to designing, testing and mapping of the µ-scale combustor}, series = {IEEE International Conference on Sustainable Energy Technologies, 2008 : ICSET 2008 ; Singapore, 24 - 27 Nov. 2008.}, journal = {IEEE International Conference on Sustainable Energy Technologies, 2008 : ICSET 2008 ; Singapore, 24 - 27 Nov. 2008.}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4244-1887-9}, pages = {656 -- 660}, year = {2008}, language = {en} } @article{WilsonBlome2009, author = {Wilson, T. L. and Blome, Hans-Joachim}, title = {The Pioneer anomaly and a rotating G{\"o}del universe}, series = {Advances in Space Research}, volume = {44}, journal = {Advances in Space Research}, number = {11}, isbn = {0273-1177}, pages = {1345 -- 1353}, year = {2009}, language = {en} } @article{HavermannSalveTinetal.1994, author = {Havermann, Marc and Salve, M. de and Tin, G. del and Panella, B.}, title = {Experimental Study of the Temperature Field along a Density Lock / Salve, M. de ; Tin, G. del ; Panella, B. ; Sansoldo, D. ; Havermann, M.}, series = {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}, journal = {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}, publisher = {-}, address = {Pisa}, pages = {623 -- 630}, year = {1994}, language = {en} } @article{HavermannBeylich1998, author = {Havermann, Marc and Beylich, A. E.}, title = {Combined Measurement of Velocity, Temperature and Pressure in Compressible Gas Flows Using Laser-Induced Iodine Fluorescence / Havermann, M. ; Beylich, A. E.}, publisher = {-}, year = {1998}, language = {en} } @article{HavermannSeilerGeorgeetal.2002, author = {Havermann, Marc and Seiler, F. and George, A. and Leopold, F.}, title = {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.}, series = {10th International Symposium on Flow Visualization : Kyōto, Japan, August 26 - 29, 2002 / sponsored by International Flow Visualization Society . [Chairman:] Toshio Kobayashi}, journal = {10th International Symposium on Flow Visualization : Kyōto, Japan, August 26 - 29, 2002 / sponsored by International Flow Visualization Society . [Chairman:] Toshio Kobayashi}, publisher = {Visualization Society of Japan}, address = {Kyoto}, isbn = {4906497829}, year = {2002}, language = {en} } @article{LeyPlescherScholzetal.2007, author = {Ley, Wilfried and Plescher, Engelbert and Scholz, Artur and Piepenbrock, Johannes}, title = {COMPASS-1 picosatellite project / Ley, Wilfried ; Plescher, Engelbert ; Scholz, Artur ; Piepenbrock, Johannes}, series = {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 R{\"o}ser; Arnoldo Valenzuela}, journal = {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 R{\"o}ser; Arnoldo Valenzuela}, publisher = {Wissenschaft und Technik Verl.}, address = {Berlin}, isbn = {9783896855718}, pages = {147 -- 150}, year = {2007}, language = {en} } @article{WittmannKehrWillnecker2000, author = {Wittmann, Klaus and Kehr, J. and Willnecker, R.}, title = {Decentralized Payload Operations Concept for Columbus}, year = {2000}, language = {en} } @article{Wittmann2000, author = {Wittmann, Klaus}, title = {Overview of Space Operations at DLR}, year = {2000}, language = {en} } @article{Mertens1992, author = {Mertens, Josef}, title = {Laminar flow for supersonic transports}, series = {Proceedings : March 16 - 18, 1992, Congress Centrum, Hamburg, Federal Republic of Germany / organized jointly by: Deutsche Gesellschaft f{\"u}r Luft- und Raumfahrt e.V. ... [Programme committee J. Szodruch ...]}, journal = {Proceedings : March 16 - 18, 1992, Congress Centrum, Hamburg, Federal Republic of Germany / organized jointly by: Deutsche Gesellschaft f{\"u}r Luft- und Raumfahrt e.V. ... [Programme committee J. Szodruch ...]}, publisher = {DGLR}, address = {Bonn}, isbn = {3-922010-73-3}, pages = {319 -- 323}, year = {1992}, language = {en} } @article{Gerhardt2005, author = {Gerhardt, Hans Joachim}, title = {Design methods of smoke and heat exhaust systems in construction works}, series = {V Mie\&\#796;dzynarodowa Konferencja Bezpiecze\&\#324;stwo Po\&\#380;arowe Budowli, Warszawa-Miedzeszyn, 14 - 16 listopada 2005 r. = : Vth International Conference Fire Safety of Buildings / ITB ... [Ed. Miros\&\#322;aw Kosiorek]}, journal = {V Mie\&\#796;dzynarodowa Konferencja Bezpiecze\&\#324;stwo Po\&\#380;arowe Budowli, Warszawa-Miedzeszyn, 14 - 16 listopada 2005 r. = : Vth International Conference Fire Safety of Buildings / ITB ... [Ed. Miros\&\#322;aw Kosiorek]}, publisher = {ITB}, address = {Warszawa}, isbn = {83-7413-810-6}, pages = {127 -- 140}, year = {2005}, language = {en} } @article{GerhardtKonrathLieb2005, author = {Gerhardt, Hans Joachim and Konrath, B. and Lieb, R.-D.}, title = {Das Drallrohr}, series = {HLH : L{\"u}ftung, Klima, Heizung, Sanit{\"a}r, Geb{\"a}udetechnik. 56 (2005), H. 11}, journal = {HLH : L{\"u}ftung, Klima, Heizung, Sanit{\"a}r, Geb{\"a}udetechnik. 56 (2005), H. 11}, isbn = {1436-5103}, pages = {91 -- 95}, year = {2005}, language = {en} } @article{GerhardtKrueger1997, author = {Gerhardt, Hans Joachim and Kr{\"u}ger, O.}, title = {Building shape influence on local wind loads}, series = {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}, journal = {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}, publisher = {Servizi Grafici Editoriali}, address = {Padova}, isbn = {88-86281-19-6}, pages = {XIX, S. 1017 - 1998 : Ill., graph. Darst.}, year = {1997}, language = {en} } @article{FunkeDickhoffKeinzetal.2014, author = {Funke, Harald and Dickhoff, J. and Keinz, Jan and Anis, H. A. and Parente, A. and Hendrick, P.}, title = {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}, series = {Energy procedia}, journal = {Energy procedia}, number = {61}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1876-6102 (E-Journal)}, doi = {10.1016/j.egypro.2014.12.201}, pages = {1736 -- 1739}, year = {2014}, abstract = {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.}, language = {en} } @article{SchirraWatmuffBauschat2014, author = {Schirra, Julian and Watmuff, Jonathan and Bauschat, J.-Michael}, title = {Highly non-planar lifting systems: a relative assessment of existing potential-methodologies to accurately estimate the induced drag}, series = {32nd AIAA Applied Aerodynamics Conference 2014 : June, 16-20 2014, Atlanta, Ga.}, journal = {32nd AIAA Applied Aerodynamics Conference 2014 : June, 16-20 2014, Atlanta, Ga.}, organization = {American Institute of Aeronautics and Astronautics}, isbn = {978-1-62410-288-2}, doi = {10.2514/6.2014-2988}, pages = {Publ. online}, year = {2014}, language = {en} } @article{BindalSharmaJanseretal.2013, author = {Bindal, Gaurav and Sharma, Sparsh and Janser, Frank and Neu, Eugen}, title = {Detailed analysis of variables affecting wing kinematics of bat flight}, series = {SAE International Journal of Aerospace}, volume = {6}, journal = {SAE International Journal of Aerospace}, number = {2}, issn = {1946-3901}, doi = {10.4271/2013-01-9003}, pages = {811 -- 818}, year = {2013}, language = {en} } @article{StadlerGarveyEmbsetal.2014, author = {Stadler, Alexander Maximilian and Garvey, Christopher J. and Embs, Jan Peter and Koza, Michael Marek and Unruh, Tobias and Artmann, Gerhard and Zaccai, Guiseppe}, title = {Picosecond dynamics in haemoglobin from different species: A quasielastic neutron scattering study}, series = {Biochimica et biophysica acta (BBA): General Subjects}, volume = {1840}, journal = {Biochimica et biophysica acta (BBA): General Subjects}, number = {10}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1872-8006 (E-Journal); 0304-4165 (Print)}, doi = {10.1016/j.bbagen.2014.06.007}, pages = {2989 -- 2999}, year = {2014}, language = {en} } @article{MathiakPlescherWillnecker2005, author = {Mathiak, Gerhard and Plescher, Engelbert and Willnecker, Rainer}, title = {Liquid metal diffusion experiments in microgravity - Vibrational effects}, series = {Measurement science and technology}, volume = {Vol. 16}, journal = {Measurement science and technology}, number = {No. 2}, issn = {0957-0233}, doi = {10.1088/0957-0233/16/2/003}, pages = {336}, year = {2005}, language = {en} } @article{MathiakWillneckerPlescher2005, author = {Mathiak, Gerhard and Willnecker, Rainer and Plescher, Engelbert}, title = {Vibrational effects on diffusion experiments}, series = {Microgravity science and technology : international journal for microgravity research and applications}, volume = {Vol. 15}, journal = {Microgravity science and technology : international journal for microgravity research and applications}, number = {No. 1}, issn = {0938-0108}, pages = {295 -- 300}, year = {2005}, language = {en} } @article{FunkeBeckmann2022, author = {Funke, Harald and Beckmann, Nils}, title = {Flexible fuel operation of a Dry-Low-NOx Micromix Combustor with Variable Hydrogen Methane Mixture}, series = {International Journal of Gas Turbine, Propulsion and Power Systems}, volume = {13}, journal = {International Journal of Gas Turbine, Propulsion and Power Systems}, number = {2}, issn = {1882-5079}, pages = {1 -- 7}, year = {2022}, abstract = {The role of hydrogen (H2) as a carbon-free energy carrier is discussed since decades for reducing greenhouse gas emissions. As bridge technology towards a hydrogen-based energy supply, fuel mixtures of natural gas or methane (CH4) and hydrogen are possible. The paper presents the first test results of a low-emission Micromix combustor designed for flexible-fuel operation with variable H2/CH4 mixtures. The numerical and experimental approach for considering variable fuel mixtures instead of recently investigated pure hydrogen is described. In the experimental studies, a first generation FuelFlex Micromix combustor geometry is tested at atmospheric pressure at gas turbine operating conditions corresponding to part- and full-load. The H2/CH4 fuel mixture composition is varied between 57 and 100 vol.\% hydrogen content. Despite the challenges flexible-fuel operation poses onto the design of a combustion system, the evaluated FuelFlex Micromix prototype shows a significant low NOx performance}, language = {en} } @article{PeloniDachwaldCeriotti2017, author = {Peloni, Alessandro and Dachwald, Bernd and Ceriotti, Matteo}, title = {Multiple near-earth asteroid rendezvous mission: Solar-sailing options}, series = {Advances in Space Research}, journal = {Advances in Space Research}, number = {In Press, Corrected Proof}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0273-1177}, doi = {10.1016/j.asr.2017.10.017}, year = {2017}, language = {en} } @article{DachwaldSeboldtLoebetal.2008, author = {Dachwald, Bernd and Seboldt, Wolfgang and Loeb, H. W. and Schartner, Karl-Heinz}, title = {Main Belt Asteroid Sample Return Mission Using Solar Electric Propulsion}, series = {Acta Astronautica. 63 (2008), H. 1-4}, journal = {Acta Astronautica. 63 (2008), H. 1-4}, isbn = {0094-5765}, pages = {91 -- 101}, year = {2008}, language = {en} } @article{KezerashviliDachwald2021, author = {Kezerashvili, Roman Ya and Dachwald, Bernd}, title = {Preface: Solar sailing: Concepts, technology, and missions II}, series = {Advances in Space Research}, volume = {67}, journal = {Advances in Space Research}, number = {9}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0273-1177}, doi = {10.1016/j.asr.2021.01.037}, pages = {2559 -- 2560}, year = {2021}, language = {en} } @article{DachwaldBaturkinCoverstoneetal.2006, author = {Dachwald, Bernd and Baturkin, Volodymyr and Coverstone, Victoria L. and Dietrich, Benjamin and Garbe, Gregory P. and G{\"o}rlich, Marianne and Leipold, Manfred and Lura, Franz and Macdonald, Malcolm and McInnes, Colin R. and Mengali, Giovanni and Quatra, Alessandro A. and Rios-Reyes, Leonel and Scheeres, Daniel J. and Seboldt, Wolfgang and Wie, Bong}, title = {Potential Effects of Optical Solar Sail Degradation on Interplanetary Trajectory Design}, series = {Astrodynamics 2005 : proceedings of the AAS/AIAA astrodynamics conference held August 7 - 11, 2005, South Lake Tahoe, California / ed. by Bobby G. Williams. - Pt. 3. - (Advances in the astronautical sciences ; 123,3)}, journal = {Astrodynamics 2005 : proceedings of the AAS/AIAA astrodynamics conference held August 7 - 11, 2005, South Lake Tahoe, California / ed. by Bobby G. Williams. - Pt. 3. - (Advances in the astronautical sciences ; 123,3)}, publisher = {Univelt}, address = {San Diego, Calif.}, isbn = {0-87703-527-X}, pages = {2569 -- 2592}, year = {2006}, language = {en} } @article{DachwaldSeboldtRichter2006, author = {Dachwald, Bernd and Seboldt, Wolfgang and Richter, L.}, title = {Multiple rendezvous and sample return missions to near-Earth objects using solar sailcraft / Dachwald, B. ; Seboldt, W. ; Richter, L.}, series = {Acta Astronautica. 59 (2006), H. 8-11}, journal = {Acta Astronautica. 59 (2006), H. 8-11}, isbn = {0094-5765}, pages = {768 -- 776}, year = {2006}, language = {en} } @article{Dachwald2004, author = {Dachwald, Bernd}, title = {Evolutionary Neurocontrol: A Smart Method for Global Optimization of Low-Thrust Trajectories}, series = {22nd AIAA Applied Aerodynamics Conference and Exhibit - AIAA/AAS Astrodynamics Specialist Conference and Exhibit - AIAA Guidance, Navigation, and Control Conference and Exhibit - AIAA Modeling and Simulation Technologies Conference and Exhibit - AIAA Atmospheric Flight Mechanics Conference and Exhibit : 16 - 19 August 2004, Providence, Rhode Island / American Institute of Aeronautics and Astronautics. - (AIAA meeting papers on disc ; 2004,14-15)}, journal = {22nd AIAA Applied Aerodynamics Conference and Exhibit - AIAA/AAS Astrodynamics Specialist Conference and Exhibit - AIAA Guidance, Navigation, and Control Conference and Exhibit - AIAA Modeling and Simulation Technologies Conference and Exhibit - AIAA Atmospheric Flight Mechanics Conference and Exhibit : 16 - 19 August 2004, Providence, Rhode Island / American Institute of Aeronautics and Astronautics. - (AIAA meeting papers on disc ; 2004,14-15)}, publisher = {American Inst. of Aeronautics and Astronautics}, address = {Reston, Va.}, pages = {2 CD-ROMs}, year = {2004}, language = {en} } @article{HeiligersSchoutetensDachwald2021, author = {Heiligers, Jeannette and Schoutetens, Frederic and Dachwald, Bernd}, title = {Photon-sail equilibria in the alpha centauri system}, series = {Journal of Guidance, Control, and Dynamics}, volume = {44}, journal = {Journal of Guidance, Control, and Dynamics}, number = {5}, issn = {1533-3884}, doi = {10.2514/1.G005446}, pages = {1053 -- 1061}, year = {2021}, language = {en} } @article{NeuJanserKhatibietal.2016, author = {Neu, Eugen and Janser, Frank and Khatibi, Akbar A. and Braun, Carsten and Orifici, Adrian C.}, title = {Operational Modal Analysis of a wing excited by transonic flow}, series = {Aerospace Science and Technology}, volume = {49}, journal = {Aerospace Science and Technology}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1270-9638}, doi = {10.1016/j.ast.2015.11.032}, pages = {73 -- 79}, year = {2016}, abstract = {Operational Modal Analysis (OMA) is a promising candidate for flutter testing and Structural Health Monitoring (SHM) of aircraft wings that are passively excited by wind loads. However, no studies have been published where OMA is tested in transonic flows, which is the dominant condition for large civil aircraft and is characterized by complex and unique aerodynamic phenomena. We use data from the HIRENASD large-scale wind tunnel experiment to automatically extract modal parameters from an ambiently excited wing operated in the transonic regime using two OMA methods: Stochastic Subspace Identification (SSI) and Frequency Domain Decomposition (FDD). The system response is evaluated based on accelerometer measurements. The excitation is investigated from surface pressure measurements. The forcing function is shown to be non-white, non-stationary and contaminated by narrow-banded transonic disturbances. All these properties violate fundamental OMA assumptions about the forcing function. Despite this, all physical modes in the investigated frequency range were successfully identified, and in addition transonic pressure waves were identified as physical modes as well. The SSI method showed superior identification capabilities for the investigated case. The investigation shows that complex transonic flows can interfere with OMA. This can make existing approaches for modal tracking unsuitable for their application to aircraft wings operated in the transonic flight regime. Approaches to separate the true physical modes from the transonic disturbances are discussed.}, language = {en} } @article{GoettenHavermannBraunetal.2020, author = {G{\"o}tten, Falk and Havermann, Marc and Braun, Carsten and Marino, Matthew and Bil, Cees}, title = {Airfoil drag at low-to-medium reynolds numbers: A novel estimation method}, series = {AIAA Journal}, volume = {58}, journal = {AIAA Journal}, number = {7}, publisher = {AIAA}, address = {Reston, Va.}, issn = {1533-385X}, doi = {10.2514/1.J058983}, pages = {2791 -- 2805}, year = {2020}, abstract = {This paper presents a novel method for airfoil drag estimation at Reynolds numbers between 4×10⁵ and 4×10⁶. The novel method is based on a systematic study of 40 airfoils applying over 600 numerical simulations and considering natural transition. The influence of the airfoil thickness-to-chord ratio, camber, and freestream Reynolds number on both friction and pressure drag is analyzed in detail. Natural transition significantly affects drag characteristics and leads to distinct drag minima for different Reynolds numbers and thickness-to-chord ratios. The results of the systematic study are used to develop empirical correlations that can accurately predict an airfoil drag at low-lift conditions. The new approach estimates a transition location based on airfoil thickness-to-chord ratio, camber, and Reynolds number. It uses the transition location in a mixed laminar-turbulent skin-friction calculation, and corrects the skin-friction coefficient for separation effects. Pressure drag is estimated separately based on correlations of thickness-to-chord ratio, camber, and Reynolds number. The novel method shows excellent accuracy when compared with wind-tunnel measurements of multiple airfoils. It is easily integrable into existing aircraft design environments and is highly beneficial in the conceptual design stage.}, language = {en} } @article{ThomaThomessenGardietal.2023, author = {Thoma, Andreas and Thomessen, Karolin and Gardi, Alessandro and Fisher, A. and Braun, Carsten}, title = {Prioritising paths: An improved cost function for local path planning for UAV in medical applications}, series = {The Aeronautical Journal}, journal = {The Aeronautical Journal}, number = {First View}, publisher = {Cambridge University Press}, address = {Cambridge}, issn = {0001-9240 (Print)}, doi = {10.1017/aer.2023.68}, pages = {1 -- 18}, year = {2023}, abstract = {Even the shortest flight through unknown, cluttered environments requires reliable local path planning algorithms to avoid unforeseen obstacles. The algorithm must evaluate alternative flight paths and identify the best path if an obstacle blocks its way. Commonly, weighted sums are used here. This work shows that weighted Chebyshev distances and factorial achievement scalarising functions are suitable alternatives to weighted sums if combined with the 3DVFH* local path planning algorithm. Both methods considerably reduce the failure probability of simulated flights in various environments. The standard 3DVFH* uses a weighted sum and has a failure probability of 50\% in the test environments. A factorial achievement scalarising function, which minimises the worst combination of two out of four objective functions, reaches a failure probability of 26\%; A weighted Chebyshev distance, which optimises the worst objective, has a failure probability of 30\%. These results show promise for further enhancements and to support broader applicability.}, language = {en} } @article{KochBoehnischVerdoncketal.2024, author = {Koch, Christopher and B{\"o}hnisch, Nils and Verdonck, Hendrik and Hach, Oliver and Braun, Carsten}, title = {Comparison of unsteady low- and mid-fidelity propeller aerodynamic methods for whirl flutter applications}, series = {Applied Sciences}, volume = {14}, journal = {Applied Sciences}, number = {2}, publisher = {MDPI}, address = {Basel}, issn = {2076-3417}, doi = {10.3390/app14020850}, pages = {1 -- 28}, year = {2024}, abstract = {Aircraft configurations with propellers have been drawing more attention in recent times, partly due to new propulsion concepts based on hydrogen fuel cells and electric motors. These configurations are prone to whirl flutter, which is an aeroelastic instability affecting airframes with elastically supported propellers. It commonly needs to be mitigated already during the design phase of such configurations, requiring, among other things, unsteady aerodynamic transfer functions for the propeller. However, no comprehensive assessment of unsteady propeller aerodynamics for aeroelastic analysis is available in the literature. This paper provides a detailed comparison of nine different low- to mid-fidelity aerodynamic methods, demonstrating their impact on linear, unsteady aerodynamics, as well as whirl flutter stability prediction. Quasi-steady and unsteady methods for blade lift with or without coupling to blade element momentum theory are evaluated and compared to mid-fidelity potential flow solvers (UPM and DUST) and classical, derivative-based methods. Time-domain identification of frequency-domain transfer functions for the unsteady propeller hub loads is used to compare the different methods. Predictions of the minimum required pylon stiffness for stability show good agreement among the mid-fidelity methods. The differences in the stability predictions for the low-fidelity methods are higher. Most methods studied yield a more unstable system than classical, derivative-based whirl flutter analysis, indicating that the use of more sophisticated aerodynamic modeling techniques might be required for accurate whirl flutter prediction.}, language = {en} } @article{DachwaldMengaliQuartaetal.2007, author = {Dachwald, Bernd and Mengali, Giovanni and Quarta, Alessandro A. and Circi, Christian}, title = {Refined Solar Sail Force Model with Mission Application / Giovanni Mengali ; Alessandro A. Quarta , Christian Circi ; Bernd Dachwald}, series = {Journal of Guidance, Control, and Dynamics. 30 (2007), H. 2}, journal = {Journal of Guidance, Control, and Dynamics. 30 (2007), H. 2}, isbn = {0162-3192}, pages = {512 -- 520}, year = {2007}, language = {en} } @article{DachwaldOhndorfWie2006, author = {Dachwald, Bernd and Ohndorf, A. and Wie, Bong}, title = {Solar Sail Trajectory Optimization for the Solar Polar Imager (SPI) Mission}, series = {AIAA Guidance, Navigation, and Control Conference \& Exhibit - AIAA Atmospheric Flight Mechanics Conference \& Exhibit - AIAA Modeling and Simulation Technologies Conference \& Exhibit - AIAA/AAS Astrodynamics Specialist Conference \& Exhibit : [21 - 24 August 2006, Keystone, Colorado ; papers]. - (AIAA meeting papers on disc ; [11.]2006,19-20 )}, journal = {AIAA Guidance, Navigation, and Control Conference \& Exhibit - AIAA Atmospheric Flight Mechanics Conference \& Exhibit - AIAA Modeling and Simulation Technologies Conference \& Exhibit - AIAA/AAS Astrodynamics Specialist Conference \& Exhibit : [21 - 24 August 2006, Keystone, Colorado ; papers]. - (AIAA meeting papers on disc ; [11.]2006,19-20 )}, publisher = {American Institute of Aeronautics and Astronautics}, address = {Reston, Va.}, isbn = {1-56347-802-1}, pages = {2 CD-ROMs.}, year = {2006}, language = {en} } @article{DachwaldSchmidtSeboldtetal.2003, author = {Dachwald, Bernd and Schmidt, Tanja D. and Seboldt, Wolfgang and Auweter-Kurtz,}, title = {Flight Opportunities from Mars to Earth for Piloted Missions Using Continuous Thrust Propulsion / Schmidt, Tanja D. ; Dachwald, Bernd ; Seboldt, Wolfgang ; Auweter-Kurtz, Monika}, publisher = {-}, pages = {1 -- 9}, year = {2003}, language = {en} } @article{HeinEubanksHibberdetal.2020, author = {Hein, Andreas M. and Eubanks, T. Marshall and Hibberd, Adam and Fries, Dan and Schneider, Jean and Lingam, Manasvi and Kennedy, Robert and Perakis, Nikolaos and Dachwald, Bernd and Kervella, Pierre}, title = {Interstellar Now! Missions to and sample returns from nearby interstellar objects}, publisher = {Elsevier}, address = {Amsterdam}, pages = {1 -- 8}, year = {2020}, abstract = {The recently discovered first high velocity hyperbolic objects passing through the Solar System, 1I/'Oumuamua and 2I/Borisov, have raised the question about near term missions to Interstellar Objects. In situ spacecraft exploration of these objects will allow the direct determination of both their structure and their chemical and isotopic composition, enabling an entirely new way of studying small bodies from outside our solar system. In this paper, we map various Interstellar Object classes to mission types, demonstrating that missions to a range of Interstellar Object classes are feasible, using existing or near-term technology. We describe flyby, rendezvous and sample return missions to interstellar objects, showing various ways to explore these bodies characterizing their surface, dynamics, structure and composition. Interstellar objects likely formed very far from the solar system in both time and space; their direct exploration will constrain their formation and history, situating them within the dynamical and chemical evolution of the Galaxy. These mission types also provide the opportunity to explore solar system bodies and perform measurements in the far outer solar system.}, language = {en} } @article{CampenKowalskiLyonsetal.2019, author = {Campen, R. and Kowalski, Julia and Lyons, W.B. and Tulaczyk, S. and Dachwald, Bernd and Pettit, E. and Welch, K. A. and Mikucki, J.A.}, title = {Microbial diversity of an Antarctic subglacial community and high-resolution replicate sampling inform hydrological connectivity in a polar desert}, series = {Environmental Microbiology}, journal = {Environmental Microbiology}, number = {accepted article}, publisher = {Wiley}, address = {Weinheim}, issn = {1462-2920}, doi = {10.1111/1462-2920.14607}, year = {2019}, language = {en} } @article{DachwaldSeboldt2005, author = {Dachwald, Bernd and Seboldt, Wolfgang}, title = {Multiple Near-Earth Asteroid Rendezvous and Sample Return Using First Generation Solar Sailcraft}, series = {Acta Astronautica. 57 (2005), H. 11}, journal = {Acta Astronautica. 57 (2005), H. 11}, isbn = {0094-5765}, pages = {864 -- 875}, year = {2005}, language = {en} } @article{SchaelAtanasyanBerdugoetal.2019, author = {Schael, S. and Atanasyan, A. and Berdugo, J. and Bretz, T. and Czupalla, Markus and Dachwald, Bernd and Doetinchem, P. von and Duranti, M. and Gast, H. and Karpinski, W. and Kirn, T. and L{\"u}belsmeyer, K. and Ma{\~n}a, C. and Marrocchesi, P.S. and Mertsch, P. and Moskalenko, I.V. and Schervan, T. and Schluse, M. and Schr{\"o}der, K.-U. and Schultz von Dratzig, A. and Senatore, C. and Spies, L. and Wakely, S.P. and Wlochal, M. and Uglietti, D. and Zimmermann, J.}, title = {AMS-100: The next generation magnetic spectrometer in space - An international science platform for physics and astrophysics at Lagrange point 2}, series = {Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment}, volume = {944}, journal = {Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment}, number = {162561}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0168-9002}, doi = {10.1016/j.nima.2019.162561}, year = {2019}, language = {en} } @article{DachwaldSeboldt2003, author = {Dachwald, Bernd and Seboldt, Wolfgang}, title = {Solar sailcraft of the first generation mission applications to near-earth asteroids}, year = {2003}, language = {en} } @article{GoettenHavermannBraunetal.2021, author = {G{\"o}tten, Falk and Havermann, Marc and Braun, Carsten and Marino, Matthew and Bil, Cees}, title = {Aerodynamic Investigations of UAV Sensor Turrets - A Combined Wind-tunnel and CFD Approach}, series = {SciTech 2021, AIAA SciTech Forum, online, WW, Jan 11-15, 2021}, journal = {SciTech 2021, AIAA SciTech Forum, online, WW, Jan 11-15, 2021}, publisher = {AIAA}, address = {Reston, Va.}, doi = {10.2514/6.2021-1535}, pages = {1 -- 12}, year = {2021}, language = {en} } @article{Dachwald2005, author = {Dachwald, Bernd}, title = {Optimization of very-low-thrust trajectories using evolutionary neurocontrol}, series = {Acta Astronautica}, volume = {57}, journal = {Acta Astronautica}, number = {2-8}, publisher = {Elsevier}, address = {Amsterdam [u.a.]}, isbn = {1879-2030}, pages = {175 -- 185}, year = {2005}, abstract = {Searching optimal interplanetary trajectories for low-thrust spacecraft is usually a difficult and time-consuming task that involves much experience and expert knowledge in astrodynamics and optimal control theory. This is because the convergence behavior of traditional local optimizers, which are based on numerical optimal control methods, depends on an adequate initial guess, which is often hard to find, especially for very-low-thrust trajectories that necessitate many revolutions around the sun. The obtained solutions are typically close to the initial guess that is rarely close to the (unknown) global optimum. Within this paper, trajectory optimization problems are attacked from the perspective of artificial intelligence and machine learning. Inspired by natural archetypes, a smart global method for low-thrust trajectory optimization is proposed that fuses artificial neural networks and evolutionary algorithms into so-called evolutionary neurocontrollers. This novel method runs without an initial guess and does not require the attendance of an expert in astrodynamics and optimal control theory. This paper details how evolutionary neurocontrol works and how it could be implemented. The performance of the method is assessed for three different interplanetary missions with a thrust to mass ratio <0.15mN/kg (solar sail and nuclear electric).}, language = {en} } @article{FingerBilBraun2019, author = {Finger, Felix and Bil, Cees and Braun, Carsten}, title = {Initial Sizing Methodology for Hybrid-Electric General Aviation Aircraft}, series = {Journal of Aircraft}, volume = {57}, journal = {Journal of Aircraft}, number = {2}, issn = {1533-3868}, doi = {10.2514/1.C035428}, pages = {245 -- 255}, year = {2019}, language = {en} } @article{FunkeBeckmannKeinzetal.2019, author = {Funke, Harald and Beckmann, Nils and Keinz, Jan and Abanteriba, Sylvester}, title = {Numerical and Experimental Evaluation of a Dual-Fuel Dry-Low-NOx Micromix Combustor for Industrial Gas Turbine Applications}, series = {Journal of Thermal Science and Engineering Applications}, volume = {11}, journal = {Journal of Thermal Science and Engineering Applications}, number = {1}, publisher = {ASME}, address = {New York}, issn = {19485085}, doi = {10.1115/1.4041495}, pages = {011015}, year = {2019}, language = {en} } @article{DachwaldCarnelliVasile2007, author = {Dachwald, Bernd and Carnelli, I. and Vasile, M.}, title = {Optimizing low-thrust gravity assist interplanetary trajectories using evolutionary neurocontrollers / I. Carnelli ; B. Dachwald ; M. Vasile}, series = {IEEE Congress on Evolutionary Computation, 2007 : CEC 2007 ; 25 - 28 September 2007, Singapore}, journal = {IEEE Congress on Evolutionary Computation, 2007 : CEC 2007 ; 25 - 28 September 2007, Singapore}, publisher = {IEEE Service Center}, address = {Piscataway, NJ}, isbn = {978-1-424-41339-3}, pages = {965 -- 972}, year = {2007}, language = {en} } @article{DachwaldMcDonaldMcInnesetal.2007, author = {Dachwald, Bernd and McDonald, Malcolm and McInnes, Colin R. and Mengali, Giovanni}, title = {Impact of Optical Degradation on Solar Sail Mission Performance}, series = {Journal of Spacecraft and Rockets. 44 (2007), H. 4}, journal = {Journal of Spacecraft and Rockets. 44 (2007), H. 4}, isbn = {0022-4650}, pages = {740 -- 749}, year = {2007}, language = {en} } @article{KonstantinidisFloresMartinezDachwaldetal.2015, author = {Konstantinidis, Konstantinos and Flores Martinez, Claudio and Dachwald, Bernd and Ohndorf, Andreas and Dykta, Paul and Bowitz, Pascal and Rudolph, Martin and Digel, Ilya and Kowalski, Julia and Voigt, Konstantin and F{\"o}rstner, Roger}, title = {A lander mission to probe subglacial water on Saturn's moon enceladus for life}, series = {Acta astronautica}, volume = {Vol. 106}, journal = {Acta astronautica}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1879-2030 (E-Journal); 0094-5765 (Print)}, pages = {63 -- 89}, year = {2015}, language = {en} } @article{DachwaldUlamecPostbergetal.2020, author = {Dachwald, Bernd and Ulamec, Stephan and Postberg, Frank and Sohl, Frank and Vera, Jean-Pierre de and Christoph, Waldmann and Lorenz, Ralph D. and Hellard, Hugo and Biele, Jens and Rettberg, Petra}, title = {Key technologies and instrumentation for subsurface exploration of ocean worlds}, series = {Space Science Reviews}, volume = {216}, journal = {Space Science Reviews}, number = {Art. 83}, publisher = {Springer}, address = {Dordrecht}, issn = {1572-9672}, doi = {10.1007/s11214-020-00707-5}, pages = {45}, year = {2020}, abstract = {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.}, language = {en} } @article{DachwaldWi2007, author = {Dachwald, Bernd and Wi, Bong}, title = {Solar Sail Kinetic Energy Impactor Trajectory Optimization for an Asteroid-Deflection Mission}, series = {Journal of Spacecraft and Rockets. 44 (2007), H. 4}, journal = {Journal of Spacecraft and Rockets. 44 (2007), H. 4}, isbn = {0022-4650}, pages = {755 -- 764}, year = {2007}, language = {en} } @article{Dachwald2004, author = {Dachwald, Bernd}, title = {Minimum Transfer Times for Nonperfectly Reflecting Solar Sailcraft}, series = {Journal of Spacecraft and Rockets. 41 (2004), H. 4}, journal = {Journal of Spacecraft and Rockets. 41 (2004), H. 4}, isbn = {0022-4650}, pages = {693 -- 695}, year = {2004}, language = {en} } @article{Dachwald2004, author = {Dachwald, Bernd}, title = {Optimization of Interplanetary Solar Sailcraft Trajectories Using Evolutionary Neurocontrol}, series = {Journal of guidance, control, and dynamics. 27 (2004), H. 1}, journal = {Journal of guidance, control, and dynamics. 27 (2004), H. 1}, isbn = {0162-3192}, pages = {66 -- 72}, year = {2004}, language = {en} } @article{DachwaldOhndorfGill2009, author = {Dachwald, Bernd and Ohndorf, A. and Gill, E.}, title = {Optimization of low-thrust Earth-Moon transfers using evolutionary neurocontrol / Ohndorf, A. ; Dachwald, B. ; Gill, E.}, series = {IEEE Congress on Evolutionary Computation, 2009. CEC '09.}, journal = {IEEE Congress on Evolutionary Computation, 2009. CEC '09.}, isbn = {978-1-4244-2958-5}, pages = {358 -- 364}, year = {2009}, language = {en} } @article{ScholzRomagnoliDachwaldetal.2011, author = {Scholz, Christina and Romagnoli, Daniele and Dachwald, Bernd and Theil, Stephan}, title = {Performance analysis of an attitude control system for solar sails using sliding masses}, series = {Advances in Space Research}, volume = {48}, journal = {Advances in Space Research}, number = {11}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0273-1177}, pages = {1822 -- 1835}, year = {2011}, language = {en} } @article{LeipoldFichtnerHeberetal.2006, author = {Leipold, M. and Fichtner, H. and Heber, B. and Groepper, P. and Lascar, S. and Burger, F. and Eiden, M. and Niederstadt, T. and Sickinger, C. and Herbeck, L. and Dachwald, Bernd and Seboldt, Wolfgang}, title = {Heliopause Explorer - A Sailcraft Mission to the Outer Boundaries of the Solar System}, series = {Acta Astronautica. 59 (2006), H. 8-11}, journal = {Acta Astronautica. 59 (2006), H. 8-11}, isbn = {0094-5765}, pages = {786 -- 796}, year = {2006}, language = {en} } @article{DachwaldTuryshevDittusetal.2005, author = {Dachwald, Bernd and Turyshev, Slava G. and Dittus, H. and Shao, M. [u.a.]}, title = {Fundamental Physics with the Laser Astrometric Test Of Relativity / S.G. Turyshev ; H. Dittus ; M. Shao ... B.Dachwald ...}, series = {Proceedings of the 39th ESLAB Symposium "Trends in Space Science and Cosmic Vision 2020" : 19 - 21 April 2005, ESTEC, Noordwijk, the Netherlands / European Space Agency. [Comp. by: F. Favata ...] . - (ESA SP ; 588)}, journal = {Proceedings of the 39th ESLAB Symposium "Trends in Space Science and Cosmic Vision 2020" : 19 - 21 April 2005, ESTEC, Noordwijk, the Netherlands / European Space Agency. [Comp. by: F. Favata ...] . - (ESA SP ; 588)}, publisher = {ESA Publ. Div.}, address = {Noordwijk}, isbn = {9290928999}, pages = {8 -- 11}, year = {2005}, language = {en} } @article{DittusTuryshevDachwaldetal.2005, author = {Dittus, H. and Turyshev, S. G. and Dachwald, Bernd and Blome, Hans-Joachim}, title = {A Mission to Explore the Pioneer Anomaly}, series = {Proceedings of the 39th ESLAB Symposium "Trends in Space Science and Cosmic Vision 2020" : 19 - 21 April 2005, ESTEC, Noordwijk, the Netherlands / European Space Agency. [Comp. by: F. Favata ...] . - (ESA SP ; 588)}, journal = {Proceedings of the 39th ESLAB Symposium "Trends in Space Science and Cosmic Vision 2020" : 19 - 21 April 2005, ESTEC, Noordwijk, the Netherlands / European Space Agency. [Comp. by: F. Favata ...] . - (ESA SP ; 588)}, publisher = {ESA Publ. Div.}, address = {Noordwijk}, isbn = {9290928999}, pages = {3 -- 10}, year = {2005}, language = {en} } @article{DachwaldMacDonaldMcInnes2007, author = {Dachwald, Bernd and MacDonald, Malcolm and McInnes, Colin R.}, title = {Heliocentric Solar Sail Orbit Transfers with Locally Optimal Control Laws / Malcolm Macdonald ; Colin McInnes ; Bernd Dachwald}, series = {Journal of Spacecraft and Rockets. 44 (2007), H. 1}, journal = {Journal of Spacecraft and Rockets. 44 (2007), H. 1}, isbn = {0022-4650}, pages = {273 -- 276}, year = {2007}, language = {en} } @article{DachwaldSeboldt2005, author = {Dachwald, Bernd and Seboldt, Wolfgang}, title = {Solar Sails for Near- and Medium-Term Scientific Deep Space Missions / W. Sebolt ; B. Dachwald}, series = {In-space propulsion : edited book of proceedings of the 10-IWCP, the 10th International Workshop on Combustion and Propulsion held in Lerici, La Spezia, Italy, 21-25 September 2003 / [ed.: Luigi T. DeLuca]}, journal = {In-space propulsion : edited book of proceedings of the 10-IWCP, the 10th International Workshop on Combustion and Propulsion held in Lerici, La Spezia, Italy, 21-25 September 2003 / [ed.: Luigi T. DeLuca]}, publisher = {SP Lab, Politecnico di Milano}, address = {Milano}, pages = {getr. Z{\"a}hlung . Ill.}, year = {2005}, language = {en} } @article{DachwaldCarnelliVasile2006, author = {Dachwald, Bernd and Carnelli, I. and Vasile, M.}, title = {Evolutionary Neurocontrol as a Novel Method for Low-Thrust Gravity Assist Trajectory Optimization / I. Carnelli ; B. Dachwald ; M. Vasile}, series = {Proceedings of the Twenty-Fifth International Symposium on Space Technology and Science (Selected papers) : Kanazawa, [June 4 through June 11, 2006, at Kanazawa-shi Kanko Kaikan in Kanazawa city] / [Japan Society for Aeronautical and Space Sciences. Kohtaro Matsumoto [ed.-in-chief]}, journal = {Proceedings of the Twenty-Fifth International Symposium on Space Technology and Science (Selected papers) : Kanazawa, [June 4 through June 11, 2006, at Kanazawa-shi Kanko Kaikan in Kanazawa city] / [Japan Society for Aeronautical and Space Sciences. Kohtaro Matsumoto [ed.-in-chief]}, publisher = {JSASS}, address = {Tokyo}, isbn = {4-99005-002-9}, pages = {569 -- 574}, year = {2006}, language = {en} } @article{DachwaldCarnelliVasile2006, author = {Dachwald, Bernd and Carnelli, I. and Vasile, M.}, title = {Low-Thrust Gravity Assist Trajectory Optimization Using Evolutionary Neurocontrollers / I. Carnelli ; B. Dachwald ; M. Vasile ...}, series = {Astrodynamics 2005 : proceedings of the AAS/AIAA astrodynamics conference held August 7 - 11, 2005, South Lake Tahoe, California / ed. by Bobby G. Williams. - Pt. 3. - (Advances in the astronautical sciences ; 123,3)}, journal = {Astrodynamics 2005 : proceedings of the AAS/AIAA astrodynamics conference held August 7 - 11, 2005, South Lake Tahoe, California / ed. by Bobby G. Williams. - Pt. 3. - (Advances in the astronautical sciences ; 123,3)}, publisher = {Univelt}, address = {San Diego, Calif.}, isbn = {0-87703-527-X}, pages = {1911 -- 1928}, year = {2006}, language = {en} } @article{DachwaldLeipoldFichtner2003, author = {Dachwald, Bernd and Leipold, M. and Fichtner, H.}, title = {Heliopause Explorer - A Sailcraft Mission to the Outer Boundaries of the Solar System / M. Leipold ; H. Fichtner ; B. Heber ... B. Dachwald ...}, series = {Proceedings of the Fifth IAA International Conference on Low Cost Planetary Missions : 24 - 26 September 2003, ESTEC, Noordwijk, the Netherlands / [comp. by R. A. Harris]}, journal = {Proceedings of the Fifth IAA International Conference on Low Cost Planetary Missions : 24 - 26 September 2003, ESTEC, Noordwijk, the Netherlands / [comp. by R. A. Harris]}, publisher = {ESA}, address = {Noordwijk}, isbn = {92-9092-853-0}, pages = {367 -- 375}, year = {2003}, language = {en} } @article{Dachwald2004, author = {Dachwald, Bernd}, title = {Interplanetary Mission Analysis for Non-Perfectly Reflecting Solar Sailcraft Using Evolutionary Neurocontrol}, series = {Astrodynamics 2003 : proceedings of the AAS/AIAA Astrodynamics Conference held August 3 - 7, 2003, Big Sky, Montana / ed. by Jean de Lafontaine. - Pt. 2. - (Advances in the astronautical sciences ; 116,2)}, journal = {Astrodynamics 2003 : proceedings of the AAS/AIAA Astrodynamics Conference held August 3 - 7, 2003, Big Sky, Montana / ed. by Jean de Lafontaine. - Pt. 2. - (Advances in the astronautical sciences ; 116,2)}, publisher = {Univelt}, address = {San Diego, Calif.}, isbn = {0-87703-509-1}, pages = {1247 -- 1262}, year = {2004}, language = {en} } @article{DachwaldSeboldt2002, author = {Dachwald, Bernd and Seboldt, Wolfgang}, title = {Optimization of Interplanetary Rendezvous Trajectories for Solar Sailcraft Using a Neurocontroller}, series = {A collection of technical papers / AIAA Astrodynamics Specialist Conference : Monterey, California, 5 - 8 August 2002. - Vol. 2}, journal = {A collection of technical papers / AIAA Astrodynamics Specialist Conference : Monterey, California, 5 - 8 August 2002. - Vol. 2}, publisher = {American Institute of Aeronautics and Astronautics}, address = {Reston, Va.}, isbn = {1-56347-549-9}, pages = {1263 -- 1270}, year = {2002}, language = {en} } @article{SchirraBissonnetteBramesfeld2018, author = {Schirra, Julian and Bissonnette, William and Bramesfeld, G{\"o}tz}, title = {Wake-model effects on induced drag prediction of staggered boxwings}, series = {Aerospace}, volume = {5}, journal = {Aerospace}, number = {1}, issn = {2226-4310}, doi = {10.3390/aerospace5010014}, year = {2018}, language = {en} } @article{KreyerMuellerEsch2020, author = {Kreyer, J{\"o}rg and M{\"u}ller, Marvin and Esch, Thomas}, title = {A Calculation Methodology for Predicting Exhaust Mass Flows and Exhaust Temperature Profiles for Heavy-Duty Vehicles}, series = {SAE International Journal of Commercial Vehicles}, volume = {13}, journal = {SAE International Journal of Commercial Vehicles}, number = {2}, publisher = {SAE International}, address = {Warrendale, Pa.}, issn = {1946-3928}, doi = {10.4271/02-13-02-0009}, pages = {129 -- 143}, year = {2020}, abstract = {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.}, language = {en} } @article{MeyerGranrathFeyerletal.2021, author = {Meyer, Max-Arno and Granrath, Christian and Feyerl, G{\"u}nter and Richenhagen, Johannes and Kaths, Jakob and Andert, Jakob}, title = {Closed-loop platoon simulation with cooperative intelligent transportation systems based on vehicle-to-X communication}, series = {Simulation Modelling Practice and Theory}, volume = {106}, journal = {Simulation Modelling Practice and Theory}, number = {Art. 102173}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1569-190X}, doi = {10.1016/j.simpat.2020.102173}, year = {2021}, language = {en} } @article{GazdaMaurischat2020, author = {Gazda, Quentin and Maurischat, Andreas}, title = {Special functions and Gauss-Thakur sums in higher rank and dimension}, publisher = {De Gruyter}, address = {Berlin}, pages = {26 Seiten}, year = {2020}, language = {en} } @article{KhayyamJamaliBabHadiasharetal.2020, author = {Khayyam, Hamid and Jamali, Ali and Bab-Hadiashar, Alireza and Esch, Thomas and Ramakrishna, Seeram and Jalil, Mahdi and Naebe, Minoo}, title = {A Novel Hybrid Machine Learning Algorithm for Limited and Big Data Modelling with Application in Industry 4.0}, series = {IEEE Access}, journal = {IEEE Access}, publisher = {IEEE}, address = {New York, NY}, isbn = {2169-3536}, doi = {10.1109/ACCESS.2020.2999898}, pages = {1 -- 12}, year = {2020}, abstract = {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.}, language = {en} } @article{HailerWeberNevelingetal.2020, author = {Hailer, Benjamin and Weber, Tobias and Neveling, Sebastian and Dera, Samuel and Arent, Jan-Christoph and Middendorf, Peter}, title = {Development of a test device to determine the frictional behavior between honeycomb and prepreg layers under realistic manufacturing conditions}, series = {Journal of Sandwich Structures \& Materials}, journal = {Journal of Sandwich Structures \& Materials}, number = {Volume 23, Issue 7}, publisher = {Sage}, address = {London}, issn = {1530-7972}, doi = {10.1177/1099636220923986}, pages = {3017 -- 3043}, year = {2020}, abstract = {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.}, language = {en} } @article{Maurischat2022, author = {Maurischat, Andreas}, title = {Algebraic independence of the Carlitz period and its hyperderivatives}, series = {Journal of Number Theory}, volume = {240}, journal = {Journal of Number Theory}, publisher = {Elsevier}, address = {Orlando, Fla.}, issn = {0022-314X}, doi = {10.1016/j.jnt.2022.01.006}, pages = {145 -- 162}, year = {2022}, language = {en} } @article{TekinAshikagaHorikawaetal.2018, author = {Tekin, Nurettin and Ashikaga, Mitsugu and Horikawa, Atsushi and Funke, Harald}, title = {Enhancement of fuel flexibility of industrial gas turbines by development of innovative hydrogen combustion systems}, series = {Gas for energy}, journal = {Gas for energy}, number = {2}, publisher = {Vulkan-Verlag}, address = {Essen}, pages = {4}, year = {2018}, abstract = {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.}, language = {en} }