@inproceedings{KronigerHorikawaFunkeetal.2021,
  author    = {Kroniger, Daniel and Horikawa, Atsushi and Funke, Harald and Pf{\"a}ffle, Franziska and Kishimoto, Tsuyoshi and Okada, Koichi},
  title     = {Experimental and numerical investigation on the effect of pressure on micromix hydrogen combustion},
  series = {ASME Turbo Expo 2021: Turbomachinery Technical Conference and Exposition // Volume 3A: Combustion, Fuels, and Emissions},
  booktitle = {ASME Turbo Expo 2021: Turbomachinery Technical Conference and Exposition // Volume 3A: Combustion, Fuels, and Emissions},
  doi       = {10.1115/GT2021-58926},
  pages     = {11 Seiten},
  year      = {2021},
  abstract  = {The micromix (MMX) combustion concept is a DLN gas turbine combustion technology designed for high hydrogen content fuels. Multiple non-premixed miniaturized flames based on jet in cross-flow (JICF) are inherently safe against flashback and ensure a stable operation in various operative conditions. The objective of this paper is to investigate the influence of pressure on the micromix flame with focus on the flame initiation point and the NOx emissions. A numerical model based on a steady RANS approach and the Complex Chemistry model with relevant reactions of the GRI 3.0 mechanism is used to predict the reactive flow and NOx emissions at various pressure conditions. Regarding the turbulence-chemical interaction, the Laminar Flame Concept (LFC) and the Eddy Dissipation Concept (EDC) are compared. The numerical results are validated against experimental results that have been acquired at a high pressure test facility for industrial can-type gas turbine combustors with regard to flame initiation and NOx emissions. The numerical approach is adequate to predict the flame initiation point and NOx emission trends. Interestingly, the flame shifts its initiation point during the pressure increase in upstream direction, whereby the flame attachment shifts from anchoring behind a downstream located bluff body towards anchoring directly at the hydrogen jet. The LFC predicts this change and the NOx emissions more accurately than the EDC. The resulting NOx correlation regarding the pressure is similar to a non-premixed type combustion configuration.},
  language  = {en}
}
@inproceedings{HorikawaOkadaYamaguchietal.2021,
  author    = {Horikawa, Atsushi and Okada, Kunio and Yamaguchi, Masato and Aoki, Shigeki and Wirsum, Manfred and Funke, Harald and Kusterer, Karsten},
  title     = {Combustor development and engine demonstration of micro-mix hydrogen combustion applied to M1A-17 gas turbine},
  series = {ASME Turbo Expo 2021: Turbomachinery Technical Conference and Exposition // Volume 3B: Combustion, Fuels, and Emissions},
  booktitle = {ASME Turbo Expo 2021: Turbomachinery Technical Conference and Exposition // Volume 3B: Combustion, Fuels, and Emissions},
  doi       = {10.1115/GT2021-59666},
  pages     = {13 Seiten},
  year      = {2021},
  abstract  = {Kawasaki Heavy Industries, LTD. (KHI) has research and development projects for a future hydrogen society. These projects comprise the complete hydrogen cycle, including the production of hydrogen gas, the refinement and liquefaction for transportation and storage, and finally the utilization in a gas turbine for electricity and heat supply. Within the development of the hydrogen gas turbine, the key technology is stable and low NOx hydrogen combustion, namely the Dry Low NOx (DLN) hydrogen combustion. KHI, Aachen University of Applied Science, and B\&B-AGEMA have investigated the possibility of low NOx micro-mix hydrogen combustion and its application to an industrial gas turbine combustor. From 2014 to 2018, KHI developed a DLN hydrogen combustor for a 2MW class industrial gas turbine with the micro-mix technology. Thereby, the ignition performance, the flame stability for equivalent rotational speed, and higher load conditions were investigated. NOx emission values were kept about half of the Air Pollution Control Law in Japan: 84ppm (O2-15\%). Hereby, the elementary combustor development was completed. From May 2020, KHI started the engine demonstration operation by using an M1A-17 gas turbine with a co-generation system located in the hydrogen-fueled power generation plant in Kobe City, Japan. During the first engine demonstration tests, adjustments of engine starting and load control with fuel staging were investigated. On 21st May, the electrical power output reached 1,635 kW, which corresponds to 100\% load (ambient temperature 20 °C), and thereby NOx emissions of 65 ppm (O2-15, 60 RH\%) were verified. Here, for the first time, a DLN hydrogen-fueled gas turbine successfully generated power and heat.},
  language  = {en}
}
@inproceedings{KronigerHorikawaFunkeetal.2021,
  author    = {Kroniger, Daniel and Horikawa, Atsushi and Funke, Harald and Pf{\"a}ffle, Franziska},
  title     = {Numerical investigation of micromix hydrogen flames at different combustor pressure levels},
  series = {Proceedings of the International Conference on Power Engineering 2021},
  booktitle = {Proceedings of the International Conference on Power Engineering 2021},
  pages     = {4 Seiten},
  year      = {2021},
  abstract  = {This study investigates the influence of pressure on the temperature distribution of the micromix (MMX) hydrogen flame and the NOx emissions. A steady computational fluid dynamic (CFD) analysis is performed by simulating a reactive flow with a detailed chemical reaction model. The numerical analysis is validated based on experimental investigations. A quantitative correlation is parametrized based on the numerical results. We find, that the flame initiation point shifts with increasing pressure from anchoring behind a downstream located bluff body towards anchoring upstream at the hydrogen jet. The numerical NOx emissions trend regarding to a variation of pressure is in good agreement with the experimental results. The pressure has an impact on both, the residence time within the maximum temperature region and on the peak temperature itself. In conclusion, the numerical model proved to be adequate for future prototype design exploration studies targeting on improving the operating range.},
  language  = {en}
}
@inproceedings{Dachwald2004,
  author    = {Dachwald, Bernd},
  title     = {Solar sail performance requirements for missions to the outer solar system and beyond},
  series = {55th International Astronautical Congress 2004},
  booktitle = {55th International Astronautical Congress 2004},
  doi       = {10.2514/6.IAC-04-S.P.11},
  pages     = {1 -- 9},
  year      = {2004},
  abstract  = {Solar sails enable missions to the outer solar system and beyond, although the solar radiation pressure decreases with the square of solar distance. For such missions, the solar sail may gain a large amount of energy by first making one or more close approaches to the sun. Within this paper, optimal trajectories for solar sail missions to the outer planets and into near interstellar space (200 AU) are presented. Thereby, it is shown that even near/medium-term solar sails with relatively moderate performance allow reasonable transfer times to the boundaries of the solar system.},
  language  = {en}
}
@article{PeloniCeriottiDachwald2016,
  author    = {Peloni, Alessandro and Ceriotti, Matteo and Dachwald, Bernd},
  title     = {Solar-sail trajectory design for a multiple near-earth-asteroid rendezvous mission},
  series = {Journal of Guidance, Control, and Dynamics},
  volume    = {39},
  journal   = {Journal of Guidance, Control, and Dynamics},
  number    = {12},
  publisher = {AIAA},
  address   = {Reston, Va.},
  issn      = {0731-5090},
  doi       = {10.2514/1.G000470},
  pages     = {2712 -- 2724},
  year      = {2016},
  abstract  = {The scientific interest for near-Earth asteroids as well as the interest in potentially hazardous asteroids from the perspective of planetary defense led the space community to focus on near-Earth asteroid mission studies. A multiple near-Earth asteroid rendezvous mission with close-up observations of several objects can help to improve the characterization of these asteroids. This work explores the design of a solar-sail spacecraft for such a mission, focusing on the search of possible sequences of encounters and the trajectory optimization. This is done in two sequential steps: a sequence search by means of a simplified trajectory model and a set of heuristic rules based on astrodynamics, and a subsequent optimization phase. A shape-based approach for solar sailing has been developed and is used for the first phase. The effectiveness of the proposed approach is demonstrated through a fully optimized multiple near-Earth asteroid rendezvous mission. The results show that it is possible to visit five near-Earth asteroids within 10 years with near-term solar-sail technology.},
  language  = {en}
}
@inproceedings{HauggKreyerKemperetal.2020,
  author    = {Haugg, Albert Thomas and Kreyer, J{\"o}rg and Kemper, Hans and Hatesuer, Katerina and Esch, Thomas},
  title     = {Heat exchanger for ORC. adaptability and optimisation potentials},
  series = {IIR International Rankine 2020 Conference},
  booktitle = {IIR International Rankine 2020 Conference},
  doi       = {10.18462/iir.rankine.2020.1224},
  pages     = {10 Seiten},
  year      = {2020},
  abstract  = {The recovery of waste heat requires heat exchangers to extract it from a liquid or gaseous medium into another working medium, a refrigerant. In Organic Rankine Cycles (ORC) on Combustion Engines there are two major heat sources, the exhaust gas and the water/glycol fluid from the engine's cooling circuit. A heat exchanger design must be adapted to the different requirements and conditions resulting from the heat sources, fluids, system configurations, geometric restrictions, and etcetera. The Stacked Shell Cooler (SSC) is a new and very specific design of a plate heat exchanger, created by AKG, which allows with a maximum degree of freedom the optimization of heat exchange rate and the reduction of the related pressure drop. This optimization in heat exchanger design for ORC systems is even more important, because it reduces the energy consumption of the system and therefore maximizes the increase in overall efficiency of the engine.},
  language  = {en}
}
@inproceedings{EnglhardWeberArent2021,
  author    = {Englhard, Markus and Weber, Tobias and Arent, Jan-Christoph},
  title     = {Efficiency enhancement for CFRP-Prepregautoclave manufacturing by means of simulation-assisted loading optimization},
  series = {Proceedings of SAMPE Europe Conference 2021},
  booktitle = {Proceedings of SAMPE Europe Conference 2021},
  pages     = {8 Seiten},
  year      = {2021},
  abstract  = {A new method for improved autoclave loading within the restrictive framework of helicopter manufacturing is proposed. It is derived from experimental and numerical studies of the curing process and aims at optimizing tooling positions in the autoclave for fast and homogeneous heat-up. The mold positioning is based on two sets of information. The thermal properties of the molds, which can be determined via semi-empirical thermal simulation. The second information is a previously determined distribution of heat transfer coefficients inside the autoclave. Finally, an experimental proof of concept is performed to show a cycle time reduction of up to 31\% using the proposed methodology.},
  language  = {en}
}
@inproceedings{GrundmannBauerBodenetal.2019,
  author    = {Grundmann, Jan Thimo and Bauer, Waldemar and Boden, Ralf and Ceriotti, Matteo and Chand, Suditi and Cordero, Federico and Dachwald, Bernd and Dumont, Etienne and Grimm, Christian D. and Heiligers, Jeannette and Herč{\´i}k, David and H{\´e}rique, Alain and Ho, Tra-Mi and Jahnke, Rico and Kofman, Wlodek and Lange, Caroline and Lichtenheldt, Roy and McInnes, Colin and Meß, Jan-Gerd and Mikschl, Tobias and Mikulz, Eugen and Montenegro, Sergio and Moore, Iain and Pelivan, Ivanka and Peloni, Alessandro and Plettemeier, Dirk and Quantius, Dominik and Reershemius, Siebo and Renger, Thomas and Riemann, Johannes and Rogez, Yves and Ruffer, Michael and Sasaki, Kaname and Schmitz, Nicole and Seboldt, Wolfgang and Seefeldt, Patric and Spietz, Peter and Spr{\"o}witz, Tom and Sznajder, Maciej and T{\´o}th, Norbert and Vergaaij, Merel and Viavattene, Giulia and Wejmo, Elisabet and Wiedemann, Carsten and Wolff, Friederike and Ziach, Christian},
  title     = {Flights are ten a sail - Re-use and commonality in the design and system engineering of small spacecraft solar sail missions with modular hardware for responsive and adaptive exploration},
  series = {70th International Astronautical Congress (IAC)},
  booktitle = {70th International Astronautical Congress (IAC)},
  isbn      = {9781713814856},
  pages     = {1 -- 7},
  year      = {2019},
  language  = {en}
}
@article{HeinEubanksLingametal.2022,
  author    = {Hein, Andreas M. and Eubanks, T. Marshall and Lingam, Manasvi and Hibberd, Adam and Fries, Dan and Schneider, Jean and Kervella, Pierre and Kennedy, Robert and Perakis, Nikolaos and Dachwald, Bernd},
  title     = {Interstellar now! Missions to explore nearby interstellar objects},
  series = {Advances in Space Research},
  volume    = {69},
  journal   = {Advances in Space Research},
  number    = {1},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0273-1177},
  doi       = {10.1016/j.asr.2021.06.052},
  pages     = {402 -- 414},
  year      = {2022},
  abstract  = {The recently discovered first 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. 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{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}
}