@inproceedings{FingerBraunBil2017, author = {Finger, Felix and Braun, Carsten and Bil, Cees}, title = {A Review of Configuration Design for Distributed Propulsion Transitioning VTOL Aircraft}, series = {Asia-Pacific International Symposium on Aerospace Technology 2017, APISAT 2017, Seoul, Korea}, booktitle = {Asia-Pacific International Symposium on Aerospace Technology 2017, APISAT 2017, Seoul, Korea}, pages = {15 Seiten}, year = {2017}, language = {en} } @inproceedings{Wahle1983, author = {Wahle, Michael}, title = {Determination of flow induced nonlinear vibrations of prestressed heat exchanger tubes}, series = {Advanced Course in Heat Exchangers : Theory and Practice ; ICHMT Symposium ; Dubrovnik, Croatia 1981. - (ICHMT digital library online ; 19)}, booktitle = {Advanced Course in Heat Exchangers : Theory and Practice ; ICHMT Symposium ; Dubrovnik, Croatia 1981. - (ICHMT digital library online ; 19)}, publisher = {Begell House}, address = {Redding, Connecticut}, pages = {339 -- 353}, year = {1983}, language = {en} } @inproceedings{Wahle1987, author = {Wahle, Michael}, title = {Optimale Auslegung von Schwingungsd{\"a}mpfern zur Schwingungsberuhigung elastischer Strukturen}, series = {D{\"a}mpfung von Schwingungen bei Maschinen und Bauwerken : Tagung N{\"u}rnberg, 9. u. 10. April 1987. - (VDI-Berichte ; 627)}, booktitle = {D{\"a}mpfung von Schwingungen bei Maschinen und Bauwerken : Tagung N{\"u}rnberg, 9. u. 10. April 1987. - (VDI-Berichte ; 627)}, publisher = {VDI-Verl.}, address = {D{\"u}sseldorf}, isbn = {3-18-090627-8}, pages = {355 -- 373}, year = {1987}, language = {de} } @inproceedings{KohlbergerWildKasperetal.2021, author = {Kohlberger, David-Sharif and Wild, Dominik and Kasper, Stefan and Czupalla, Markus}, title = {Modeling and analyses of a thermal passively stabilized LEO/GEO star tracker with embedded phase change material applying the Infused Thermal Solutions (ITS) method}, series = {ICES202: Satellite, Payload, and Instrument Thermal Control}, booktitle = {ICES202: Satellite, Payload, and Instrument Thermal Control}, publisher = {Texas Tech University}, address = {Lubbock, Tex.}, pages = {12 Seiten}, year = {2021}, abstract = {Phase change materials offer a way of storing excess heat and releasing it when it is needed. They can be utilized as a method to control thermal behavior without the need for additional energy. This work focuses on exploring the potential of using phase change materials to passively control the thermal behavior of a star tracker by infusing it with a fitting phase change material. Based on the numerical model of the star trackers thermal behavior using ESATAN-TMS without implemented phase change material, a fitting phase change material for selected orbits is chosen and implemented in the thermal model. The altered thermal behavior of the numerical model after the implementation is analyzed for different amounts of the chosen phase change materials using an ESATAN-based subroutine developed by the FH Aachen. The PCM-modelling-subroutine is explained in the paper ICES-2021-110. The results show that an increasing amount of phase change material increasingly damps temperature oscillations. Using an integral part structure some of the mass increase can be compensated.}, language = {en} } @inproceedings{KreyerEsch2017, author = {Kreyer, J{\"o}rg and Esch, Thomas}, title = {Simulation Tool for Predictive Control Strategies for an ORCSystem in Heavy Duty Vehicles}, series = {European GT Conference 2017}, booktitle = {European GT Conference 2017}, pages = {16 Seiten}, year = {2017}, abstract = {Scientific questions - How can a non-stationary heat offering in the commercial vehicle be used to reduce fuel consumption? - Which potentials offer route and environmental information among with predicted speed and load trajectories to increase the efficiency of a ORC-System? Methods - Desktop bound holistic simulation model for a heavy duty truck incl. an ORC System - Prediction of massflows, temperatures and mixture quality (AFR) of exhaust gas}, language = {en} } @inproceedings{MulsowHuelsenGuetzlaffetal.2023, author = {Mulsow, Niklas A. and H{\"u}lsen, Benjamin and G{\"u}tzlaff, Joel and Spies, Leon and Bresser, Andreas and Dabrowski, Adam and Czupalla, Markus and Kirchner, Frank}, title = {Concept and design of an autonomous micro rover for long term lunar exploration}, series = {Proceedings of the 74th International Astronautical Congress}, booktitle = {Proceedings of the 74th International Astronautical Congress}, publisher = {dfki}, address = {Saarbr{\"u}cken}, pages = {13 Seiten}, year = {2023}, abstract = {Research on robotic lunar exploration has seen a broad revival, especially since the Google Lunar X-Prize increasingly brought private endeavors into play. This development is supported by national agencies with the aim of enabling long-term lunar infrastructure for in-situ operations and the establishment of a moon village. One challenge for effective exploration missions is developing a compact and lightweight robotic rover to reduce launch costs and open the possibility for secondary payload options. Existing micro rovers for exploration missions are clearly limited by their design for one day of sunlight and their low level of autonomy. For expanding the potential mission applications and range of use, an extension of lifetime could be reached by surviving the lunar night and providing a higher level of autonomy. To address this objective, the paper presents a system design concept for a lightweight micro rover with long-term mission duration capabilities, derived from a multi-day lunar mission scenario at equatorial regions. Technical solution approaches are described, analyzed, and evaluated, with emphasis put on the harmonization of hardware selection due to a strictly limited budget in dimensions and power.}, language = {en} } @inproceedings{HuelsenMulsowDabrowskietal.2023, author = {H{\"u}lsen, Benjamin and Mulsow, Niklas A. and Dabrowski, Adam and Brinkmann, Wiebke and G{\"u}tzlaff, Joel and Spies, Leon and Czupalla, Markus and Kirchner, Frank}, title = {Towards an autonomous micro rover with night survivability for lunar exploration}, series = {Proceedings of the 74th International Astronautical Congress}, booktitle = {Proceedings of the 74th International Astronautical Congress}, publisher = {dfki}, pages = {12 Seiten}, year = {2023}, abstract = {In Europe, efforts are underway to develop key technologies that can be used to explore the Moon and to exploit the resources available. This includes technologies for in-situ resource utilization (ISRU), facilitating the possibility of a future Moon Village. The Moon is the next step for humans and robots to exploit the use of available resources for longer term missions, but also for further exploration of the solar system. A challenge for effective exploration missions is to achieve a compact and lightweight robot to reduce launch costs and open up the possibility of secondary payload options. Current micro rover concepts are primarily designed to last for one day of solar illumination and show a low level of autonomy. Extending the lifetime of the system by enabling survival of the lunar night and implementing a high level of autonomy will significantly increase potential mission applications and the operational range. As a reference mission, the deployment of a micro rover in the equatorial region of the Moon is being considered. An overview of mission parameters and a detailed example mission sequence is given in this paper. The mission parameters are based on an in-depth study of current space agency roadmaps, scientific goals, and upcoming flight opportunities. Furthermore, concepts of the ongoing international micro rover developments are analyzed along with technology solutions identified for survival of lunar nights and a high system autonomy. The results provide a basis of a concise requirements set-up to allow dedicated system developments and qualification measures in the future.}, language = {en} } @inproceedings{FunkeBeckmannStefanetal.2023, author = {Funke, Harald and Beckmann, Nils and Stefan, Lukas and Keinz, Jan}, title = {Hydrogen combustor integration study for a medium range aircraft engine using the dry-low NOx "Micromix" combustion principle}, series = {Proceedings of the ASME Turbo Expo 2023: Turbomachinery Technical Conference and Exposition. Volume 1: Aircraft Engine.}, booktitle = {Proceedings of the ASME Turbo Expo 2023: Turbomachinery Technical Conference and Exposition. Volume 1: Aircraft Engine.}, publisher = {ASME}, address = {New York}, isbn = {978-0-7918-8693-9}, doi = {10.1115/GT2023-102370}, pages = {12 Seiten}, year = {2023}, abstract = {The feasibility study presents results of a hydrogen combustor integration for a Medium-Range aircraft engine using the Dry-Low-NOₓ Micromix combustion principle. Based on a simplified Airbus A320-type flight mission, a thermodynamic performance model of a kerosene and a hydrogen-powered V2530-A5 engine is used to derive the thermodynamic combustor boundary conditions. A new combustor design using the Dry-Low NOx Micromix principle is investigated by slice model CFD simulations of a single Micromix injector for design and off-design operation of the engine. Combustion characteristics show typical Micromix flame shapes and good combustion efficiencies for all flight mission operating points. Nitric oxide emissions are significant below ICAO CAEP/8 limits. For comparison of the Emission Index (EI) for NOₓ emissions between kerosene and hydrogen operation, an energy (kerosene) equivalent Emission Index is used. A full 15° sector model CFD simulation of the combustion chamber with multiple Micromix injectors including inflow homogenization and dilution and cooling air flows investigates the combustor integration effects, resulting NOₓ emission and radial temperature distributions at the combustor outlet. The results show that the integration of a Micromix hydrogen combustor in actual aircraft engines is feasible and offers, besides CO₂ free combustion, a significant reduction of NOₓ emissions compared to kerosene operation.}, language = {en} } @inproceedings{WildCzupallaFoerstner2021, author = {Wild, Dominik and Czupalla, Markus and F{\"o}rstner, Roger}, title = {Modeling, prediction and test of additive manufactured integral structures with embedded lattice and phase change material applying Infused Thermal Solutions (ITS)}, series = {ICES104: Advances in Thermal Control Technology}, booktitle = {ICES104: Advances in Thermal Control Technology}, publisher = {Texas Tech University}, address = {Lubbock, Tex.}, pages = {12 Seiten}, year = {2021}, abstract = {Infused Thermal Solutions (ITS) introduces a method for passive thermal control to stabilize structural components thermally without active heating and cooling systems, but with phase change material (PCM) for thermal energy storage (TES), in combination with lattice - both embedded in additive manufactured functional structures. In this ITS follow-on paper a thermal model approach and associated predictions are presented, related on the ITS functional breadboards developed at FH Aachen. Predictive TES by PCM is provided by a specially developed ITS PCM subroutine, which is applicable in ESATAN. The subroutine is based on the latent heat storage (LHS) method to numerically embed thermo-physical PCM behavior. Furthermore, a modeling approach is introduced to numerically consider the virtual PCM/lattice nodes within the macro-encapsulated PCM voids of the double wall ITS design. Related on these virtual nodes, in-plane and out-of-plane conductive links are defined. The recent additive manufactured ITS breadboard series are thermally cycled in the thermal vacuum chamber, both with and without embedded PCM. Related on breadboard hardware tests, measurement results are compared with predictions and are subsequently correlated. The results of specific simulations and measurements are presented. Recent predictive results of star tracker analyses are also presented in ICES-2021-106, based on this ITS PCM subroutine.}, language = {en} } @inproceedings{BarnatMergner2017, author = {Barnat, Miriam and Mergner, Julia}, title = {Forschungsbasierte Qualit{\"a}tsentwicklung am Beispiel der Analyse von Lernprozessen und der Wirksamkeit von F{\"o}rderprogrammen}, series = {3. Internationale Tagung f{\"u}r Qualit{\"a}tsmanagement und Qualit{\"a}tsentwicklung im Hochschulbereich 2.-3. Februar 2017}, booktitle = {3. Internationale Tagung f{\"u}r Qualit{\"a}tsmanagement und Qualit{\"a}tsentwicklung im Hochschulbereich 2.-3. Februar 2017}, pages = {28 Seiten}, year = {2017}, language = {de} }