@article{FunkeBeckmannKeinzetal.2018,
  author    = {Funke, Harald and Beckmann, Nils and Keinz, Jan and Abanteriba, Sylvester},
  title     = {Comparison of Numerical Combustion Models for Hydrogen and Hydrogen-Rich Syngas Applied for Dry-Low-Nox-Micromix-Combustion},
  series = {Journal of Engineering for Gas Turbines and Power},
  volume    = {140},
  journal   = {Journal of Engineering for Gas Turbines and Power},
  number    = {8},
  publisher = {ASME},
  address   = {New York, NY},
  issn      = {0742-4795},
  doi       = {10.1115/1.4038882},
  pages     = {9 Seiten},
  year      = {2018},
  abstract  = {The Dry-Low-NOx (DLN) Micromix combustion technology has been developed as low emission combustion principle for industrial gas turbines fueled with hydrogen or syngas. The combustion process is based on the phenomenon of jet-in-crossflow-mixing (JICF). Fuel is injected perpendicular into the air-cross-flow and burned in a multitude of miniaturized, diffusion-like flames. The miniaturization of the flames leads to a significant reduction of NOx emissions due to the very short residence time of reactants in the flame. In the Micromix research approach, computational fluid dynamics (CFD) analyses are validated toward experimental results. The combination of numerical and experimental methods allows an efficient design and optimization of DLN Micromix combustors concerning combustion stability and low NOx emissions. The paper presents a comparison of several numerical combustion models for hydrogen and hydrogen-rich syngas. They differ in the complexity of the underlying reaction mechanism and the associated computational effort. The performance of a hybrid eddy-break-up (EBU) model with a one-step global reaction is compared to a complex chemistry model and a flamelet generated manifolds (FGM) model, both using detailed reaction schemes for hydrogen or syngas combustion. Validation of numerical results is based on exhaust gas compositions available from experimental investigation on DLN Micromix combustors. The conducted evaluation confirms that the applied detailed combustion mechanisms are able to predict the general physics of the DLN-Micromix combustion process accurately. The FGM method proved to be generally suitable to reduce the computational effort while maintaining the accuracy of detailed chemistry.},
  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}
}
@article{MuschallikMolinnusBongaertsetal.2017,
  author    = {Muschallik, Lukas and Molinnus, Denise and Bongaerts, Johannes and Pohl, Martina and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Siegert, Petra and Selmer, Thorsten},
  title     = {(R,R)-Butane-2,3-diol Dehydrogenase from Bacillus clausii DSM 8716T: Cloning and Expression of the bdhA-Gene, and Initial Characterization of Enzyme},
  series = {Journal of Biotechnology},
  volume    = {258},
  journal   = {Journal of Biotechnology},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0168-1656},
  doi       = {10.1016/j.jbiotec.2017.07.020},
  pages     = {41 -- 50},
  year      = {2017},
  abstract  = {The gene encoding a putative (R,R)-butane-2,3-diol dehydrogenase (bdhA) from Bacillus clausii DSM 8716T was isolated, sequenced and expressed in Escherichia coli. The amino acid sequence of the encoded protein is only distantly related to previously studied enzymes (identity 33-43\%) and exhibited some uncharted peculiarities. An N-terminally StrepII-tagged enzyme variant was purified and initially characterized. The isolated enzyme catalyzed the (R)-specific oxidation of (R,R)- and meso-butane-2,3-diol to (R)- and (S)-acetoin with specific activities of 12 U/mg and 23 U/mg, respectively. Likewise, racemic acetoin was reduced with a specific activity of up to 115 U/mg yielding a mixture of (R,R)- and meso-butane-2,3-diol, while the enzyme reduced butane-2,3-dione (Vmax 74 U/mg) solely to (R,R)-butane-2,3-diol via (R)-acetoin. For these reactions only activity with the co-substrates NADH/NAD+ was observed. The enzyme accepted a selection of vicinal diketones, α-hydroxy ketones and vicinal diols as alternative substrates. Although the physiological function of the enzyme in B. clausii remains elusive, the data presented herein clearly demonstrates that the encoded enzyme is a genuine (R,R)-butane-2,3-diol dehydrogenase with potential for applications in biocatalysis and sensor development.},
  language  = {en}
}
@incollection{ReimerBraunBallmann2007,
  author    = {Reimer, Lars and Braun, Carsten and Ballmann, Josef},
  title     = {Computational study of the aeroelastic equilibrium configuration of a swept wind tunnel wing model in subsonic flow},
  series = {High performance computing in science and engineering '06. Transactions of the High Performance Computing Center Stuttgart (HLRS) 2006 / Wolfgang E. Nagel ... Eds.},
  booktitle = {High performance computing in science and engineering '06. Transactions of the High Performance Computing Center Stuttgart (HLRS) 2006 / Wolfgang E. Nagel ... Eds.},
  publisher = {Springer},
  address   = {Berlin [u.a.]},
  isbn      = {978-3-540-36165-7},
  pages     = {421 -- 434},
  year      = {2007},
  abstract  = {In the Collaborative Research Center SFB 401 at RWTH Aachen University, the numerical aeroelastic method SOFIA for direct numerical aeroelastic simulation is being progressively developed. Numerical results obtained by applying SOFIA were compared with measured data of static and dynamic aeroelastic wind tunnel tests for an elastic swept wing in subsonic flow.},
  language  = {en}
}
@article{JossekBongaertsSprenger2001,
  author    = {Jossek, Ralf and Bongaerts, Johannes and Sprenger, Georg A.},
  title     = {Characterization of a new feedback-resistant 3-deoxy-D-arabinoheptulosonate 7-phosphate synthase AroF of Escherichia coli},
  series = {FEMS microbiology letters},
  volume    = {Vol. 202},
  journal   = {FEMS microbiology letters},
  number    = {Iss. 1},
  issn      = {1574-6968},
  pages     = {145 -- 148},
  year      = {2001},
  language  = {en}
}
@article{GeierLehnertzBialonski2015,
  author    = {Geier, Christian and Lehnertz, Klaus and Bialonski, Stephan},
  title     = {Time-dependent degree-degree correlations in epileptic brain networks: from assortative to dissortative mixing},
  series = {Frontiers in Human Neuroscience},
  journal   = {Frontiers in Human Neuroscience},
  publisher = {Frontiers Research Foundation},
  address   = {Lausanne},
  issn      = {1662-5161},
  doi       = {10.3389/fnhum.2015.00462},
  year      = {2015},
  language  = {en}
}
@article{WilmingBegemannKuhneetal.2013,
  author    = {Wilming, Anja and Begemann, Jens and Kuhne, Stefan and Regestein, Lars and Bongaerts, Johannes and Evers, Stefan and Maurer, Karl-Heinz and B{\"u}chs, Jochen},
  title     = {Metabolic studies of γ-polyglutamic acid production in Bacillus licheniformis by small-scale continuous cultivations},
  series = {Biochemical engineering journal},
  volume    = {Vol. 73},
  journal   = {Biochemical engineering journal},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-295X (E-Journal); 1369-703X (Print)},
  pages     = {29 -- 37},
  year      = {2013},
  language  = {en}
}
@article{Alexopoulos2015,
  author    = {Alexopoulos, Spiros},
  title     = {Simulation model for the transient process behaviour of solar aluminium recycling in a rotary kiln},
  series = {Applied Thermal Engineering},
  volume    = {78},
  journal   = {Applied Thermal Engineering},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1359-4311},
  doi       = {10.1016/j.applthermaleng.2015.01.007},
  pages     = {387 -- 396},
  year      = {2015},
  language  = {en}
}
@inproceedings{FunkeBeckmannKeinzetal.2017,
  author    = {Funke, Harald and Beckmann, Nils and Keinz, Jan and Abanteriba, Sylvester},
  title     = {Numerical and Experimental Evaluation of a Dual-Fuel Dry-Low-NOx Micromix Combustor for Industrial Gas Turbine Applications},
  series = {Proceedings of the ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. Volume 4B: Combustion, Fuels and Emissions. Charlotte, North Carolina, USA. June 26-30, 2017},
  booktitle = {Proceedings of the ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. Volume 4B: Combustion, Fuels and Emissions. Charlotte, North Carolina, USA. June 26-30, 2017},
  publisher = {ASME},
  address   = {New York},
  isbn      = {978-0-7918-5085-5},
  doi       = {10.1115/GT2017-64795},
  year      = {2017},
  abstract  = {The Dry-Low-NOx (DLN) Micromix combustion technology has been developed originally as a low emission alternative for industrial gas turbine combustors fueled with hydrogen. Currently the ongoing research process targets flexible fuel operation with hydrogen and syngas fuel. The non-premixed combustion process features jet-in-crossflow-mixing of fuel and oxidizer and combustion through multiple miniaturized flames. The miniaturization of the flames leads to a significant reduction of NOx emissions due to the very short residence time of reactants in the flame. The paper presents the results of a numerical and experimental combustor test campaign. It is conducted as part of an integration study for a dual-fuel (H2 and H2/CO 90/10 Vol.\%) Micromix combustion chamber prototype for application under full scale, pressurized gas turbine conditions in the auxiliary power unit Honeywell Garrett GTCP 36-300. In the presented experimental studies, the integration-optimized dual-fuel Micromix combustor geometry is tested at atmospheric pressure over a range of gas turbine operating conditions with hydrogen and syngas fuel. The experimental investigations are supported by numerical combustion and flow simulations. For validation, the results of experimental exhaust gas analyses are applied. Despite the significantly differing fuel characteristics between pure hydrogen and hydrogen-rich syngas the evaluated dual-fuel Micromix prototype shows a significant low NOx performance and high combustion efficiency. The combustor features an increased energy density that benefits manufacturing complexity and costs.},
  language  = {en}
}
@article{BoehnischBraunMuscarelloetal.2024,
  author    = {B{\"o}hnisch, Nils and Braun, Carsten and Muscarello, Vincenzo and Marzocca, Pier},
  title     = {About the wing and whirl flutter of a slender wing-propeller system},
  series = {Journal of Aircraft},
  journal   = {Journal of Aircraft},
  publisher = {AIAA},
  address   = {Reston, Va.},
  issn      = {1533-3868},
  doi       = {10.2514/1.C037542},
  pages     = {1 -- 14},
  year      = {2024},
  abstract  = {Next-generation aircraft designs often incorporate multiple large propellers attached along the wingspan (distributed electric propulsion), leading to highly flexible dynamic systems that can exhibit aeroelastic instabilities. This paper introduces a validated methodology to investigate the aeroelastic instabilities of wing-propeller systems and to understand the dynamic mechanism leading to wing and whirl flutter and transition from one to the other. Factors such as nacelle positions along the wing span and chord and its propulsion system mounting stiffness are considered. Additionally, preliminary design guidelines are proposed for flutter-free wing-propeller systems applicable to novel aircraft designs. The study demonstrates how the critical speed of the wing-propeller systems is influenced by the mounting stiffness and propeller position. Weak mounting stiffnesses result in whirl flutter, while hard mounting stiffnesses lead to wing flutter. For the latter, the position of the propeller along the wing span may change the wing mode shapes and thus the flutter mechanism. Propeller positions closer to the wing tip enhance stability, but pusher configurations are more critical due to the mass distribution behind the elastic axis.},
  language  = {en}
}