@article{EschSalberKemperetal.2000, author = {Esch, Thomas and Salber, Wolfgang and Kemper, Hans and Staay, F. van der}, title = {Der elektromechanische Ventiltrieb - Systembaustein f{\"u}r zuk{\"u}nftige Antriebskonzepte, Teil 1.}, series = {Motortechnische Zeitschrift (MTZ).}, volume = {61}, journal = {Motortechnische Zeitschrift (MTZ).}, number = {12}, publisher = {Springer Nature}, address = {Basel}, issn = {0024-8525}, doi = {10.1007/bf03227081}, pages = {826 -- 836}, year = {2000}, language = {de} } @inproceedings{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 = {7th International Fluid Power Conference - Vol. 3 - Aachen Efficiency through Fluid Power Workshop Proceedings}, booktitle = {7th International Fluid Power Conference - Vol. 3 - Aachen Efficiency through Fluid Power Workshop Proceedings}, publisher = {Apprimus Verlag}, address = {Aachen}, isbn = {978-3-940565-92-1}, pages = {103 -- 114}, year = {2010}, language = {en} } @article{SchmitzAltherrHofmannetal.1998, author = {Schmitz, G{\"u}nter and Altherr, M. and Hofmann, O. and Pischinger, Martin}, title = {Anwendung moderner Simulationstools f{\"u}r die Entwicklung eines elektromagnetischen Ventilaktuators}, series = {TransMechatronik : Entwicklung und Transfer von Entwicklungssystemen der Mechatronik / Aachener Workshop TransMechatronik 26. Mai 1998, Technologiezentrum am Europaplatz}, journal = {TransMechatronik : Entwicklung und Transfer von Entwicklungssystemen der Mechatronik / Aachener Workshop TransMechatronik 26. Mai 1998, Technologiezentrum am Europaplatz}, publisher = {Heinz-Nixdorf-Inst, Univ.-GH Paderborn}, address = {Paderborn}, isbn = {3-931466-37-X}, pages = {55 -- 74}, year = {1998}, language = {de} } @article{EschPischingerGoebel1996, author = {Esch, Thomas and Pischinger, Martin and G{\"o}bel, T.}, title = {Luft- und Kraftstoffzumessung bei Ottomotoren mit variabler Ventilsteuerung}, series = {Motortechnische Zeitschrift. 57 (1996), H. 2}, journal = {Motortechnische Zeitschrift. 57 (1996), H. 2}, isbn = {0024-8525}, pages = {106 -- 115}, year = {1996}, language = {de} } @article{EschPischingerHagenetal.1998, author = {Esch, Thomas and Pischinger, Martin and Hagen, J{\"u}rgen and Salber, Wolfgang}, title = {M{\"o}glichkeiten der ottomotorischen Prozeßf{\"u}hrung bei Verwendung des elektromechanischen Ventiltriebs}, pages = {987 -- 1015}, year = {1998}, language = {de} } @book{LeyWittmannHallmann2009, author = {Ley, Wilfried and Wittmann, Klaus and Hallmann, Willi}, title = {Handbook of space technology}, publisher = {Wiley}, address = {Chichester}, isbn = {978-0-470-69739-9}, pages = {XIII, 882 S. : Ill., graph. Darst.}, year = {2009}, language = {en} } @inproceedings{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}, pages = {13 Seiten}, year = {2010}, abstract = {With the final objective of optimizing the "Micromix" hydrogen combustion principle, a round jet in a laminar cross-flow prior to its combustion is investigated experimentally using Stereoscopic Particle Image Velocimetry. Measurements are performed at a jet to cross-stream momentum ratio of 1 and a Reynolds number, based on the jet diameter and jet velocity, of 1600. The suitability to combine side, top and end views is analyzed statistically. The statistical theory of testing hypotheses, pertaining to the joint distribution of the averaged velocity along intersecting observation planes, is employed. Overall, the averaged velocity fields of the varying observation planes feature homogeneity at a 0.05 significance level. Minor discrepancies are related to the given experimental conditions. By use of image maps, averaged and instantaneous velocity fields, an attempt is made to elucidate the flow physics and a kinematically consistent vortex model is proposed. In the time-averaged flow field, the principal vortical systems were identified and the associated mixing visualized. The jet trajectory and physical dimensions scale with the momentum ratio times the jet diameter. The jet/cross-flow mixture converging upon the span-wise centre-line, the lifting action of the Counter Rotating Vortex Pair and the reversed flow region contribute to the high entrainment and mixedness. It is shown that the jet width is larger on the downstream side as compared to the upstream side of the centre-streamline. The deepest penetration of the particles on the outer boundary occurs in the centre-plane. Meanwhile, with increasing off-centre position, the boundaries all lay further from the centre-line position than does the boundary in the centre-plane, corresponding to a kidney-like shape of the flow cross-section. The generation of the Counter Rotating Vortex Pair and the instability mechanism is documented by instantaneous image maps and vector fields. The necessary circulation for the Counter Rotating Vortex Pair originates from a combined effect of steady in-hole, hanging and wake vortices. The strong cross-flow and jet interaction induces a three-dimensional waving, the stream-wise Counter Rotating Vortex Pair pair, leading to the formation of Ring Like Vortices. A secondary Counter Rotating Vortex Pair forms on top of the primary Counter Rotating Vortex Pair, resulting in mixing by "puffs". Overall, Stereoscopic Particle Image Velocimetry proofed capable of elucidating the Jet in Cross-Flow complex flow field. The gained insight in the mixing process will definitely contribute to the "Micromix" hydrogen combustion optimization.}, language = {en} } @inproceedings{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 = {Conference Proceedings ASME Turbo Expo 2010: Power for Land, Sea, and Air. Volume 5: Industrial and Cogeneration; Microturbines and Small Turbomachinery; Oil and Gas Applications; Wind Turbine Technology}, booktitle = {Conference Proceedings ASME Turbo Expo 2010: Power for Land, Sea, and Air. Volume 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}, doi = {10.1115/GT2010-23453}, pages = {587 -- 596}, year = {2010}, abstract = {For more than a decade up to now there is an ongoing interest in small gas turbines downsized to micro-scale. With their high energy density they offer a great potential as a substitute for today's unwieldy accumulators, found in a variety of applications like laptops, small tools etc. But micro-scale gas turbines could not only be used for generating electricity, they could also produce thrust for powering small unmanned aerial vehicles (UAVs) or similar devices. Beneath all the great design challenges with the rotating parts of the turbomachinery at this small scale, another crucial item is in fact the combustion chamber needed for a safe and reliable operation. With the so called regular micromix burning principle for hydrogen successfully downscaled in an initial combustion chamber prototype of 10 kW energy output, this paper describes a new design attempt aimed at the integration possibilities in a μ-scale gas turbine. For manufacturing the combustion chamber completely out of stainless steel components, a recuperative wall cooling was introduced to keep the temperatures in an acceptable range. Also a new way of an integrated ignition was developed. The detailed description of the prototype's design is followed by an in depth report about the test results. The experimental investigations comprise a set of mass flow variations, coupled with a variation of the equivalence ratio for each mass flow at different inlet temperatures and pressures. With the data obtained by an exhaust gas analysis, a full characterisation concerning combustion efficiency and stability of the prototype chamber is possible. Furthermore the data show a full compliance with the expected operating requirements of the designated μ-scale gas turbine.}, language = {en} } @inproceedings{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}, year = {2010}, language = {en} } @misc{MaiwaldDachwald2010, author = {Maiwald, Volker and Dachwald, Bernd}, title = {Mission design for a multiple-rendezvous mission to Jupiter's trojans}, pages = {3}, year = {2010}, abstract = {In this paper, we will provide a feasible mission design for a multiple-rendezvous mission to Jupiter's Trojans. It is based on solar electric propulsion, as being currently used on the DAWN spacecraft, and other flight-proven technology. First, we have selected a set of mission objectives, the prime objective being the detection of water -especially subsurface water -to provide evidence for the Trojans' formation at large solar distances. Based on DAWN and other comparable missions, we have determined suitable payload instruments to achieve these objectives. Afterwards, we have designed a spacecraft that is able to carry the selected payload to the Trojan region and rendezvous successively with three target bodies within a maximum mission duration of 15 years. Accurate low-thrust trajectories have been obtained with a global low-thrust trajectory optimization program (InTrance). During the transfer from Earth to the first target, the spacecraft is propelled by two RIT-22 ion engines from EADS Astrium, whereas a single RIT-15 is used for transfers within the Trojan region to reduce the required power. For power generation, the spacecraft uses a multi-junction solar array that is supported by concentrators. To achieve moderate mission costs, we have restricted the launch mass to a maximum of 1600 kg, the maximum interplanetary injection capability of a Soyuz/Fregat launcher. Our final layout has a mass of 1400 kg, yielding a margin of about 14\%. Nestor (a member of the L4-population) was determined as the first mission target. It can be reached within 4.6 years from launch. The fuel mass ratio for this transfer is about 35\%. The stay time at Nestor is 1.2 years. Eurymedon was selected as the second target (transfer time 3.5 years, stay time 3.0 years) and Irus as the third target (transfer time 2.2 years). The transfers within the Trojan L4-population can be accomplished with fuel mass ratios of about 3\% for each trajectory leg. Including the stay times in orbit around the targets, the mission can be accomplished within a total duration of about 14.5 years. According to our mission analysis, it is also feasible to fly to the L5-population with similar flight times. It has to be noted that -for a first analysis -we have taken only the named targets into account. Allowing also rendezvous with unnamed objects will very likely decrease the mission duration. Based on a scaling of DAWN's mission costs (due to comparable scientific instruments and mission objectives), and taking into account the longer mission duration and the potential re-use of already developed technology, we have estimated that these three rendezvous can be accomplished with a budget of about 250 Million Euros, i.e. about 25\% of ROSETTA's budget.}, language = {en} }