@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{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{DachwaldMikuckiTulaczyketal.2014, author = {Dachwald, Bernd and Mikucki, Jill and Tulaczyk, Slawek and Digel, Ilya and Espe, Clemens and Feldmann, Marco and Francke, Gero and Kowalski, Julia and Xu, Changsheng}, title = {IceMole : A maneuverable probe for clean in situ analysis and sampling of subsurface ice and subglacial aquatic ecosystems}, series = {Annals of Glaciology}, volume = {55}, journal = {Annals of Glaciology}, number = {65}, publisher = {Cambridge University Press}, address = {Cambridge}, issn = {1727-5644}, doi = {10.3189/2014AoG65A004}, pages = {14 -- 22}, year = {2014}, abstract = {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.}, 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{KraemerDaabMuelleretal.2013, author = {Kr{\"a}mer, Stefan and Daab, Dominique Jonas and M{\"u}ller, Brigitte and Wagner, Tobias and Baader, Fabian and Hessel, Joana and Gdalewitsch, Georg and Plescher, Engelbert and Dachwald, Bernd and Wahle, Michael and Gierse, Andreas and Vetter, Rudolf and Pf{\"u}tzenreuter, Lysan}, title = {Development and flight-testing of a system to isolate vibrations for microgravity experiments on sounding rockets}, series = {21st ESA Symposium on Rocket and Balloon Research}, journal = {21st ESA Symposium on Rocket and Balloon Research}, pages = {1 -- 8}, year = {2013}, 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{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{LoebSchartnerDachwaldetal.2012, author = {Loeb, Horst Wolfgang and Schartner, Karl-Heinz and Dachwald, Bernd and Ohndorf, Andreas and Seboldt, Wolfgang}, title = {Interstellar heliopause probe}, series = {Труды МАИ}, journal = {Труды МАИ}, number = {60}, publisher = {Moskauer Staatliches Luftfahrtinstitut (МАИ)}, address = {Moskau}, pages = {2 -- 2}, year = {2012}, abstract = {There is common agreement within the scientific community that in order to understand our local galactic environment it will be necessary to send a spacecraft into the region beyond the solar wind termination shock. Considering distances of 200 AU for a new mission, one needs a spacecraft traveling at a speed of close to 10 AU/yr in order to keep the mission duration in the range of less than 25 yrs, a transfer time postulated by European Space Agency (ESA). Two propulsion options for the mission have been proposed and discussed so far: the solar sail propulsion and the ballistic/radioisotope-electric propulsion (REP). As a further alternative, we here investigate a combination of solar-electric propulsion (SEP) and REP. The SEP stage consists of six 22-cms diameter RIT-22 ion thrusters working with a high specific impulse of 7377 s corresponding to a positive grid voltage of 5 kV. Solar power of 53 kW at begin of mission (BOM) is provided by a lightweight solar array.}, 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{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{DachwaldWurm2011, author = {Dachwald, Bernd and Wurm, Patrick}, title = {Mission analysis and performance comparison for an Advanced Solar Photon Thruster}, series = {Advances in Space Research}, volume = {48}, journal = {Advances in Space Research}, number = {11}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0273-1177}, pages = {1858 -- 1868}, year = {2011}, language = {en} } @article{FunkeBoernerFalketal.2011, author = {Funke, Harald and B{\"o}rner, Sebastian and Falk, F. and Hendrick, P.}, title = {Control system modifications and their effects on the operation of a hydrogen-fueled Auxiliary Power Unit}, series = {XX international symposium on air breathing engines 2011 : ISABE 2011, Gothenburg, Sweden, 12-16 September, 2011. Vol. 2.}, journal = {XX international symposium on air breathing engines 2011 : ISABE 2011, Gothenburg, Sweden, 12-16 September, 2011. Vol. 2.}, publisher = {American Institute of Aeronautics and Astronautics}, address = {Reston, VA}, isbn = {9781618391803}, pages = {929 -- 938}, year = {2011}, language = {en} } @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{FunkeReckerBosschaertsetal.2011, author = {Funke, Harald and Recker, E. and Bosschaerts, W. and Boonen, Q. and B{\"o}rner, Sebastian}, title = {Parametrical study of the „Micromix" hydrogen combustion principle}, series = {10th International Symposium on Experimental and Computational Aerothermodynamics of Internal Flows, ISAIF10-049, Brussels, Belgium, 4-7 July 2011}, journal = {10th International Symposium on Experimental and Computational Aerothermodynamics of Internal Flows, ISAIF10-049, Brussels, Belgium, 4-7 July 2011}, year = {2011}, language = {en} } @article{EschFunkeRoosenetal.2011, author = {Esch, Thomas and Funke, Harald and Roosen, Peter and Jarolimek, Ulrich}, title = {Biogenic Vehicle Fuels in General Aviation Aircrafts}, series = {MTZ worldwide. 72 (2011), H. 1}, journal = {MTZ worldwide. 72 (2011), H. 1}, publisher = {Springer Automotive Media}, address = {Wiesbaden}, pages = {38 -- 43}, year = {2011}, 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{ScholzLeyDachwaldetal.2010, author = {Scholz, A. and Ley, Wilfried and Dachwald, Bernd and Miau, J. J. and Juang, J. C.}, title = {Flight results of the COMPASS-1 picosatellite mission}, series = {Acta Astronautica. 67 (2010), H. 9-10}, journal = {Acta Astronautica. 67 (2010), H. 9-10}, isbn = {0094-5765}, pages = {1289 -- 1298}, year = {2010}, language = {en} } @article{BlomeChiconeHehletal.2010, author = {Blome, Hans-Joachim and Chicone, Carmen and Hehl, Friedrich W. and Mashhoon, Bahram}, title = {Nonlocal modification of Newtonian gravity}, series = {Physical Review D}, volume = {81}, journal = {Physical Review D}, number = {6}, isbn = {0556-2821}, pages = {065020}, year = {2010}, language = {en} } @article{MaiwaldDachwald2010, author = {Maiwald, Volker and Dachwald, Bernd}, title = {Mission Design for a Multiple-Rendezvous Mission to Jupiter's Trojans}, pages = {3}, year = {2010}, language = {en} } @article{BoernerFunkeHendricketal.2010, author = {B{\"o}rner, Sebastian and Funke, Harald and Hendrick, P. and Recker, E.}, title = {Control system modifications for a hydrogen fuelled gas-turbine}, series = {ISROMAC 13, 13th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery, Honolulu, HI, US, Apr 4-7, 2010}, journal = {ISROMAC 13, 13th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery, Honolulu, HI, US, Apr 4-7, 2010}, publisher = {Curran}, address = {Red Hook, NY}, isbn = {978-1-617-38848-4}, pages = {665 -- 670}, year = {2010}, language = {en} } @article{FunkeRobinsonHendricketal.2010, author = {Funke, Harald and Robinson, A. E. and Hendrick, P. and Wagemakers, R.}, title = {Design and Testing of a Micromix Combustor With Recuperative Wall Cooling for a Hydrogen Fuelled µ-Scale Gas Turbine}, series = {Proceedings of the ASME Turbo Expo 2010 : presented at the 2010 ASME Turbo Expo, June 14 - 18, 2010, Glasgow, UK / sponsored by the International Gas Turbine Institute / Vol. 5: Industrial and cogeneration ; microturbines and small turbomachinery ; oil and gas applications ; wind turbine technology}, journal = {Proceedings of the ASME Turbo Expo 2010 : presented at the 2010 ASME Turbo Expo, June 14 - 18, 2010, Glasgow, UK / sponsored by the International Gas Turbine Institute / Vol. 5: Industrial and cogeneration ; microturbines and small turbomachinery ; oil and gas applications ; wind turbine technology}, publisher = {ASME}, address = {New York, NY}, isbn = {978-0-7918-4400-7}, pages = {587 -- 596}, year = {2010}, language = {en} } @article{LettiniHavermannGuidettietal.2010, author = {Lettini, Antonio and Havermann, Marc and Guidetti, Marco and Fornaciari, Andrea}, title = {Improved functionalities and energy saving potential on mobile machines combining electronics with flow sharing valve and variable displacement pump}, series = {IFK 7, 7th International Fluid Power Conference, Efficiency through Fluid Power, 7. Internationales Fluidtechnisches Kolloquium, Workshop Proceedings, Vol. 3, Aachen, DE, 22.-24. Mar, 2010}, journal = {IFK 7, 7th International Fluid Power Conference, Efficiency through Fluid Power, 7. Internationales Fluidtechnisches Kolloquium, Workshop Proceedings, Vol. 3, Aachen, DE, 22.-24. Mar, 2010}, publisher = {-}, isbn = {978-3-940565-92-1}, pages = {103 -- 114}, year = {2010}, language = {en} } @article{FunkeBoernerRobinsonetal.2010, author = {Funke, Harald and B{\"o}rner, Sebastian and Robinson, A. and Hendrick, P. and Recker, E.}, title = {Low NOx H2 combustion for industrial gas turbines of various power ranges}, series = {5th International Gas Turbine Conference ETN-IGTC, ETN-2010-42, Brussels, Belgium, October 2010}, journal = {5th International Gas Turbine Conference ETN-IGTC, ETN-2010-42, Brussels, Belgium, October 2010}, year = {2010}, language = {en} } @article{ReckerBosschaertsWagemakersetal.2010, author = {Recker, Elmar and Bosschaerts, Walter and Wagemakers, Rolf and Hendrick, Patrick and Funke, Harald and B{\"o}rner, Sebastian}, title = {Experimental study of a round jet in cross-flow at low momentum ratio}, series = {15th International Symposium on Applications of Laser Techniques to Fluid Mechanics Lisbon, Portugal, 05-08 July, 2010 - 1}, journal = {15th International Symposium on Applications of Laser Techniques to Fluid Mechanics Lisbon, Portugal, 05-08 July, 2010 - 1}, pages = {1 -- 13}, year = {2010}, language = {en} } @article{Esch2010, author = {Esch, Thomas}, title = {Trends in commercial vehicle powertrains}, series = {ATZautotechnology}, volume = {2010}, journal = {ATZautotechnology}, number = {10}, publisher = {Vieweg \& Sohn}, address = {Wiesbaden}, issn = {2192-886X}, doi = {10.1007/BF03247185}, pages = {26 -- 31}, year = {2010}, abstract = {Low emission zones and truck bans, the rising price of diesel and increases in road tolls: all of these factors are putting serious pressure on the transport industry. Commercial vehicle manufacturers and their suppliers are in the process of identifying new solutions to these challenges as part of their efforts to meet the EEV (enhanced environmentally friendly vehicle) limits, which are currently the most robust European exhaust and emissions standards for trucks and buses.}, language = {en} } @article{ChristenKowalskiBartelt2010, author = {Christen, Marc and Kowalski, Julia and Bartelt, Perry}, title = {RAMMS: Numerical simulation of dense snow avalanches in three-dimensional terrain}, series = {Cold Regions Science and Technology}, volume = {63}, journal = {Cold Regions Science and Technology}, number = {1-2}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1872-7441}, doi = {10.1016/j.coldregions.2010.04.005}, pages = {1 -- 14}, year = {2010}, abstract = {Numerical avalanche dynamics models have become an essential part of snow engineering. Coupled with field observations and historical records, they are especially helpful in understanding avalanche flow in complex terrain. However, their application poses several new challenges to avalanche engineers. A detailed understanding of the avalanche phenomena is required to construct hazard scenarios which involve the careful specification of initial conditions (release zone location and dimensions) and definition of appropriate friction parameters. The interpretation of simulation results requires an understanding of the numerical solution schemes and easy to use visualization tools. We discuss these problems by presenting the computer model RAMMS, which was specially designed by the SLF as a practical tool for avalanche engineers. RAMMS solves the depth-averaged equations governing avalanche flow with accurate second-order numerical solution schemes. The model allows the specification of multiple release zones in three-dimensional terrain. Snow cover entrainment is considered. Furthermore, two different flow rheologies can be applied: the standard Voellmy-Salm (VS) approach or a random kinetic energy (RKE) model, which accounts for the random motion and inelastic interaction between snow granules. We present the governing differential equations, highlight some of the input and output features of RAMMS and then apply the models with entrainment to simulate two well-documented avalanche events recorded at the Vall{\´e}e de la Sionne test site.}, 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{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{DachwaldCarnelliVasile2009, author = {Dachwald, Bernd and Carnelli, Ian and Vasile, Massimiliano}, title = {Evolutionary Neurocontrol: A Novel Method for Low-Thrust Gravity-Assist Trajectory Optimization / Carnelli, Ian ; Dachwald, Bernd ; Vasile, Massimiliano}, series = {Journal of guidance control and dynamics. 32 (2009), H. 2}, journal = {Journal of guidance control and dynamics. 32 (2009), H. 2}, publisher = {AIAA}, address = {Reston, Va.}, isbn = {0731-5090}, pages = {616 -- 625}, year = {2009}, language = {en} } @article{DachwaldBallUlamecetal.2009, author = {Dachwald, Bernd and Ball, Andrew J. and Ulamec, Stephan and Price, Michael E.}, title = {A small mission for in situ exploration of a primitive binary near-Earth asteroid / Ball, Andrew J. ; Ulamec, Stephan ; Dachwald, Bernd ; Price, Michael E. ; [u.a.]}, series = {Advances in Space Research. 43 (2009), H. 2}, journal = {Advances in Space Research. 43 (2009), H. 2}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {0273-1177}, pages = {317 -- 324}, year = {2009}, 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{RobinsonFunkeWagemakersetal.2009, author = {Robinson, A. E. and Funke, Harald and Wagemakers, R. and Grossen, J. and Bosschaerts, W. and Hendrick, P.}, title = {Numerical and Experimental Investigation of a Micromix Combustor for a Hydrogen Fuelled μ-Scale Gas Turbine}, series = {Proceedings of the ASME Turbo Expo 2009 : : presented at the 2009 ASME Turbo Expo, June 8 - 12, 2009, Orlando, Florida, USA / sponsored by the International Gas Turbine Institute}, journal = {Proceedings of the ASME Turbo Expo 2009 : : presented at the 2009 ASME Turbo Expo, June 8 - 12, 2009, Orlando, Florida, USA / sponsored by the International Gas Turbine Institute}, publisher = {ASME}, address = {New York, NY}, isbn = {9780791848869}, pages = {253 -- 262}, year = {2009}, 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{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{DachwaldSeboldtLoebetal.2008, author = {Dachwald, Bernd and Seboldt, W. and Loeb, H. W and Schartner, K.-H.}, 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{DachwaldSeboldt2008, author = {Dachwald, Bernd and Seboldt, W.}, title = {Solar Sails — Propellantless Propulsion for Near- and Medium-Term Deep-Space Missions / W. Seboldt ; B. Dachwald}, series = {Advanced Propulsion Systems and Technologies, Today to 2020 / Claudio Bruno (ed.) ... - (Progress in Astronautics and Aeronautics Series ; 223)}, journal = {Advanced Propulsion Systems and Technologies, Today to 2020 / Claudio Bruno (ed.) ... - (Progress in Astronautics and Aeronautics Series ; 223)}, publisher = {AIAA}, address = {Reston, Va.}, isbn = {978-1-56347-929-8}, pages = {460 S.}, year = {2008}, language = {en} } @article{DachwaldSeboldtLaemmerzahl2008, author = {Dachwald, Bernd and Seboldt, W. and L{\"a}mmerzahl, W.}, title = {Solar Sail Propulsion: An Enabling Technology for Fundamental Physics Missions}, series = {Lasers, Clocks and Drag Free Control : Exploration of Relativistic Gravity in Space / by Hansj{\"o}rg Dittus ..., eds. - ( Astrophysics and Space Science Library ; 349)}, journal = {Lasers, Clocks and Drag Free Control : Exploration of Relativistic Gravity in Space / by Hansj{\"o}rg Dittus ..., eds. - ( Astrophysics and Space Science Library ; 349)}, publisher = {Springer}, address = {Berlin [u.a.]}, isbn = {978-3-540-34376-9}, pages = {379 -- 398}, year = {2008}, 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{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{FunkeRoennaRobinson2008, author = {Funke, Harald and R{\"o}nna, Uwe and Robinson, A. E.}, title = {Development and testing of a 10 kW diffusive micromix combustor for hydrogen-fuelled μ-scale gas turbines}, series = {Proceedings of ASME Turbo Expo 2008: Power for Land, Sea and Air ; GT2008 ; June 9-13, 2008, Berlin, Germany}, journal = {Proceedings of ASME Turbo Expo 2008: Power for Land, Sea and Air ; GT2008 ; June 9-13, 2008, Berlin, Germany}, publisher = {ASME}, address = {New York, NY}, pages = {1 -- 8}, year = {2008}, language = {en} } @article{DachwaldOhndorf2007, author = {Dachwald, Bernd and Ohndorf, A.}, title = {1st ACT Global Trajectory Optimisation Competition : Results found at DLR}, series = {Acta Astronautica. 61 (2007), H. 9}, journal = {Acta Astronautica. 61 (2007), H. 9}, isbn = {0094-5765}, pages = {742 -- 752}, 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{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{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{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{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} }