@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{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{GerhardtKramerJanssen1985,
  author    = {Gerhardt, Hans Joachim and Kramer, C. and Janssen, L.-J.},
  title     = {Flow studies of an open jet wind tunnel and comparison with closed and slotted walls},
  pages     = {7 -- 28},
  year      = {1985},
  language  = {en}
}
@article{HammerQuitterMayntzetal.2023,
  author    = {Hammer, Thorben and Quitter, Julius and Mayntz, Joscha and Bauschat, J.-Michael and Dahmann, Peter and G{\"o}tten, Falk and Hille, Sebastian and Stumpf, Eike},
  title     = {Free fall drag estimation of small-scale multirotor unmanned aircraft systems using computational fluid dynamics and wind tunnel experiments},
  series = {CEAS Aeronautical Journal},
  journal   = {CEAS Aeronautical Journal},
  publisher = {Springer},
  address   = {Wien},
  issn      = {1869-5590 (Online)},
  doi       = {10.1007/s13272-023-00702-w},
  pages     = {14 Seiten},
  year      = {2023},
  abstract  = {New European Union (EU) regulations for UAS operations require an operational risk analysis, which includes an estimation of the potential danger of the UAS crashing. A key parameter for the potential ground risk is the kinetic impact energy of the UAS. The kinetic energy depends on the impact velocity of the UAS and, therefore, on the aerodynamic drag and the weight during free fall. Hence, estimating the impact energy of a UAS requires an accurate drag estimation of the UAS in that state. The paper at hand presents the aerodynamic drag estimation of small-scale multirotor UAS. Multirotor UAS of various sizes and configurations were analysed with a fully unsteady Reynolds-averaged Navier-Stokes approach. These simulations included different velocities and various fuselage pitch angles of the UAS. The results were compared against force measurements performed in a subsonic wind tunnel and provided good consistency. Furthermore, the influence of the UAS`s fuselage pitch angle as well as the influence of fixed and free spinning propellers on the aerodynamic drag was analysed. Free spinning propellers may increase the drag by up to 110\%, depending on the fuselage pitch angle. Increasing the fuselage pitch angle of the UAS lowers the drag by 40\% up to 85\%, depending on the UAS. The data presented in this paper allow for increased accuracy of ground risk assessments.},
  language  = {en}
}
@article{GoettenFingerHavermannetal.2021,
  author    = {G{\"o}tten, Falk and Finger, Felix and Havermann, Marc and Braun, Carsten and Marino, M. and Bil, C.},
  title     = {Full configuration drag estimation of short-to-medium range fixed-wing UAVs and its impact on initial sizing optimization},
  series = {CEAS Aeronautical Journal},
  volume    = {12},
  journal   = {CEAS Aeronautical Journal},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1869-5590 (Online)},
  doi       = {10.1007/s13272-021-00522-w},
  pages     = {589 -- 603},
  year      = {2021},
  abstract  = {The paper presents the derivation of a new equivalent skin friction coefficient for estimating the parasitic drag of short-to-medium range fixed-wing unmanned aircraft. The new coefficient is derived from an aerodynamic analysis of ten different unmanned aircraft used for surveillance, reconnaissance, and search and rescue missions. The aircraft is simulated using a validated unsteady Reynolds-averaged Navier Stokes approach. The UAV's parasitic drag is significantly influenced by the presence of miscellaneous components like fixed landing gears or electro-optical sensor turrets. These components are responsible for almost half of an unmanned aircraft's total parasitic drag. The new equivalent skin friction coefficient accounts for these effects and is significantly higher compared to other aircraft categories. It is used to initially size an unmanned aircraft for a typical reconnaissance mission. The improved parasitic drag estimation yields a much heavier unmanned aircraft when compared to the sizing results using available drag data of manned aircraft.},
  language  = {en}
}
@article{NeuJanserKhatibietal.2017,
  author    = {Neu, Eugen and Janser, Frank and Khatibi, Akbar A. and Orifici, Adrian C.},
  title     = {Fully Automated Operational Modal Analysis using multi-stage clustering},
  series = {Mechanical Systems and Signal Processing},
  volume    = {Vol. 84, Part A},
  journal   = {Mechanical Systems and Signal Processing},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0888-3270},
  doi       = {10.1016/j.ymssp.2016.07.031},
  pages     = {308 -- 323},
  year      = {2017},
  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{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{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, W.},
  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{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{WittmannKellWinkleretal.1998,
  author    = {Wittmann, Klaus and Kell, G. and Winkler, F. and G{\"u}nther, M. (u.a.)},
  title     = {High resolution temperature measurement technique for materials sciences experiments in space},
  series = {Acta Astronautica. 43 (1998), H. 7-8},
  journal   = {Acta Astronautica. 43 (1998), H. 7-8},
  isbn      = {0094-5765},
  pages     = {385 -- 395},
  year      = {1998},
  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{BohndickBosseJaenschetal.2021,
  author    = {Bohndick, Carla and Bosse, Elke and J{\"a}nsch, Vanessa K. and Barnat, Miriam},
  title     = {How different diversity factors affect the perception of first-year requirements in higher education},
  series = {Frontline Learning Research},
  volume    = {9},
  journal   = {Frontline Learning Research},
  number    = {2},
  publisher = {EARLI},
  issn      = {2295-3159},
  doi       = {10.14786/flr.v9i2.667},
  pages     = {78 -- 95},
  year      = {2021},
  abstract  = {In the light of growing university entry rates, higher education institutions not only serve larger numbers of students, but also seek to meet first-year students' ever more diverse needs. Yet to inform universities how to support the transition to higher education, research only offers limited insights. Current studies tend to either focus on the individual factors that affect student success or they highlight students' social background and their educational biography in order to examine the achievement of selected, non-traditional groups of students. Both lines of research appear to lack integration and often fail to take organisational diversity into account, such as different types of higher education institutions or degree programmes. For a more comprehensive understanding of student diversity, the present study includes individual, social and organisational factors. To gain insights into their role for the transition to higher education, we examine how the different factors affect the students' perception of the formal and informal requirements of the first year as more or less difficult to cope with. As the perceived requirements result from both the characteristics of the students and the institutional context, they allow to investigate transition at the interface of the micro and the meso level of higher education. Latent profile analyses revealed that there are no profiles with complex patterns of perception of the first-year requirements, but the identified groups rather differ in the overall level of perceived challenges. Moreover, SEM indicates that the differences in the perception largely depend on the individual factors self-efficacy and volition.},
  language  = {en}
}
@article{DickhoffHorikawaFunke2021,
  author    = {Dickhoff, Jens and Horikawa, Atsushi and Funke, Harald},
  title     = {Hydrogen Combustion - new DLE Combustor Addresses NOx Emissions and Flashback},
  series = {Turbomachinery international : the global journal of energy equipment},
  volume    = {62},
  journal   = {Turbomachinery international : the global journal of energy equipment},
  number    = {4},
  publisher = {MJH Life Sciences},
  address   = {Cranbury},
  issn      = {2767-2328},
  pages     = {26 -- 27},
  year      = {2021},
  language  = {en}
}
@article{BlomeKundt1987,
  author    = {Blome, Hans-Joachim and Kundt, W.},
  title     = {Hypersonic Jets from Young Stars in Molecular Clouds},
  series = {Circumstellar matter : proceedings of the 122nd symposium of the Internat. Astronom. Union held in Heidelberg, FRG, June 23 - 27, 1986 / ed. by I. Appenzeller ...},
  journal   = {Circumstellar matter : proceedings of the 122nd symposium of the Internat. Astronom. Union held in Heidelberg, FRG, June 23 - 27, 1986 / ed. by I. Appenzeller ...},
  publisher = {Reidel},
  address   = {Dordrecht u.a.},
  isbn      = {90-277-2511-X},
  pages     = {73 -- 74},
  year      = {1987},
  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{FingerBraunBil2020,
  author    = {Finger, Felix and Braun, Carsten and Bil, Cees},
  title     = {Impact of Battery Performance on the Initial Sizing of Hybrid-Electric General Aviation Aircraft},
  series = {Journal of Aerospace Engineering},
  volume    = {33},
  journal   = {Journal of Aerospace Engineering},
  number    = {3},
  publisher = {ASCE},
  address   = {Reston, Va.},
  issn      = {1943-5525},
  doi       = {10.1061/(ASCE)AS.1943-5525.0001113},
  year      = {2020},
  abstract  = {Studies suggest that hybrid-electric aircraft have the potential to generate fewer emissions and be inherently quieter when compared to conventional aircraft. By operating combustion engines together with an electric propulsion system, synergistic benefits can be obtained. However, the performance of hybrid-electric aircraft is still constrained by a battery's energy density and discharge rate. In this paper, the influence of battery performance on the gross mass for a four-seat general aviation aircraft with a hybrid-electric propulsion system is analyzed. For this design study, a high-level approach is chosen, using an innovative initial sizing methodology to determine the minimum required aircraft mass for a specific set of requirements and constraints. Only the peak-load shaving operational strategy is analyzed. Both parallel- and serial-hybrid propulsion configurations are considered for two different missions. The specific energy of the battery pack is varied from 200 to 1,000 W⋅h/kg, while the discharge time, and thus the normalized discharge rating (C-rating), is varied between 30 min (2C discharge rate) and 2 min (30C discharge rate). With the peak-load shaving operating strategy, it is desirable for hybrid-electric aircraft to use a light, low capacity battery system to boost performance. For this case, the battery's specific power rating proved to be of much higher importance than for full electric designs, which have high capacity batteries. Discharge ratings of 20C allow a significant take-off mass reduction aircraft. The design point moves to higher wing loadings and higher levels of hybridization if batteries with advanced technology are used.},
  language  = {en}
}
@article{FingerBraunBil2018,
  author    = {Finger, Felix and Braun, Carsten and Bil, Cees},
  title     = {Impact of electric propulsion technology and mission requirements on the performance of VTOL UAVs},
  series = {CEAS Aeronautical Journal},
  volume    = {10},
  journal   = {CEAS Aeronautical Journal},
  number    = {3},
  publisher = {Springer},
  issn      = {1869-5582 print},
  doi       = {10.1007/s13272-018-0352-x},
  pages     = {843},
  year      = {2018},
  abstract  = {One of the engineering challenges in aviation is the design of transitioning vertical take-off and landing (VTOL) aircraft. Thrust-borne flight implies a higher mass fraction of the propulsion system, as well as much increased energy consumption in the take-off and landing phases. This mass increase is typically higher for aircraft with a separate lift propulsion system than for aircraft that use the cruise propulsion system to support a dedicated lift system. However, for a cost-benefit trade study, it is necessary to quantify the impact the VTOL requirement and propulsion configuration has on aircraft mass and size. For this reason, sizing studies are conducted. This paper explores the impact of considering a supplemental electric propulsion system for achieving hovering flight. Key variables in this study, apart from the lift system configuration, are the rotor disk loading and hover flight time, as well as the electrical systems technology level for both batteries and motors. Payload and endurance are typically used as the measures of merit for unmanned aircraft that carry electro-optical sensors, and therefore the analysis focuses on these particular parameters.},
  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{GoettenHavermannBraunetal.2020,
  author    = {G{\"o}tten, Falk and Havermann, Marc and Braun, Carsten and Marino, Matthew and Bil, Cees},
  title     = {Improved Form Factor for Drag Estimation of Fuselages with Various Cross Sections},
  series = {Journal of Aircraft},
  journal   = {Journal of Aircraft},
  publisher = {AIAA},
  address   = {Reston, Va.},
  issn      = {1533-3868},
  doi       = {10.2514/1.C036032},
  pages     = {1 -- 13},
  year      = {2020},
  abstract  = {The paper presents an aerodynamic investigation of 70 different streamlined bodies with fineness ratios ranging from 2 to 10. The bodies are chosen to idealize both unmanned and small manned aircraft fuselages and feature cross-sectional shapes that vary from circular to quadratic. The study focuses on friction and pressure drag in dependency of the individual body's fineness ratio and cross section. The drag forces are normalized with the respective body's wetted area to comply with an empirical drag estimation procedure. Although the friction drag coefficient then stays rather constant for all bodies, their pressure drag coefficients decrease with an increase in fineness ratio. Referring the pressure drag coefficient to the bodies' cross-sectional areas shows a distinct pressure drag minimum at a fineness ratio of about three. The pressure drag of bodies with a quadratic cross section is generally higher than for bodies of revolution. The results are used to derive an improved form factor that can be employed in a classic empirical drag estimation method. The improved formulation takes both the fineness ratio and cross-sectional shape into account. It shows superior accuracy in estimating streamlined body drag when compared with experimental data and other form factor formulations of the literature.},
  language  = {en}
}