@inproceedings{HorikawaOkadaUtoetal.2019,
  author    = {Horikawa, Atsushi and Okada, Kunio and Uto, Takahiro and Uchiyama, Yuta and Wirsum, Manfred and Funke, Harald and Kusterer, Karsten},
  title     = {Application of Low NOx Micro-mix Hydrogen Combustion to 2MW Class Industrial Gas Turbine Combustor},
  series = {Proceedings of International Gas Turbine Congress 2019 Tokyo, November 17-22, 2019, Tokyo, Japan},
  booktitle = {Proceedings of International Gas Turbine Congress 2019 Tokyo, November 17-22, 2019, Tokyo, Japan},
  isbn      = {978-4-89111-010-9},
  pages     = {1 -- 6},
  year      = {2019},
  language  = {en}
}
@inproceedings{FunkeBeckmann2019,
  author    = {Funke, Harald and Beckmann, Nils},
  title     = {Flexible Fuel Operation of a Dry-Low-Nox Micromix Combustor with Variable Hydrogen Methane Mixtures},
  series = {Proceedings of International Gas Turbine Congress 2019 Tokyo, November 17-22, 2019, Tokyo, Japan},
  booktitle = {Proceedings of International Gas Turbine Congress 2019 Tokyo, November 17-22, 2019, Tokyo, Japan},
  isbn      = {978-4-89111-010-9},
  year      = {2019},
  language  = {en}
}
@inproceedings{FunkeKeinzHendrick2017,
  author    = {Funke, Harald and Keinz, Jan and Hendrick, P.},
  title     = {Experimental Evaluation of the Pollutant and Noise Emissions of the GTCP 36-300 Gas Turbine Operated with Kerosene and a Low NOX Micromix Hydrogen Combustor},
  series = {7th European Conference for Aeronautics and Space Sciences, EUCASS 2017},
  booktitle = {7th European Conference for Aeronautics and Space Sciences, EUCASS 2017},
  organization    = {7th European Conference for Aeronautics and Space Sciences, EUCASS 2017-125, Milan, Italy, July 2017},
  doi       = {10.13009/EUCASS2017-125},
  pages     = {10 Seiten},
  year      = {2017},
  language  = {en}
}
@article{FunkeBeckmannKeinzetal.2019,
  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 = {Journal of Thermal Science and Engineering Applications},
  volume    = {11},
  journal   = {Journal of Thermal Science and Engineering Applications},
  number    = {1},
  publisher = {ASME},
  address   = {New York},
  issn      = {19485085},
  doi       = {10.1115/1.4041495},
  pages     = {011015},
  year      = {2019},
  language  = {en}
}
@inproceedings{StrieganStruthDickhoffetal.2019,
  author    = {Striegan, Constantin J. D. and Struth, Benjamin and Dickhoff, Jens and Kusterer, Karsten and Funke, Harald and Bohn, Dieter},
  title     = {Numerical Simulations of the Micromix DLN Hydrogen Combustion Technology with LES and Comparison to Results of RANS and Experimental Data},
  series = {Proceedings of International Gas Turbine Congress 2019 Tokyo, November 17-22, 2019, Tokyo, Japan.},
  booktitle = {Proceedings of International Gas Turbine Congress 2019 Tokyo, November 17-22, 2019, Tokyo, Japan.},
  isbn      = {978-4-89111-010-9},
  pages     = {1 -- 9},
  year      = {2019},
  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}
}
@inproceedings{StrieganHajAyedFunkeetal.2017,
  author    = {Striegan, C. and Haj Ayed, A. and Funke, Harald and Loechle, S. and Kazari, M. and Horikawa, A. and Okada, K. and Koga, K.},
  title     = {Numerical combustion and heat transfer simulations and validation for a hydrogen fueled "micromix" test combustor in industrial gas turbine applications},
  series = {Proceedings of the ASME Turbo Expo},
  booktitle = {Proceedings of the ASME Turbo Expo},
  number    = {Volume Part F130041-4B, 2017},
  isbn      = {978-079185085-5},
  doi       = {10.1115/GT2017-64719},
  year      = {2017},
  language  = {en}
}
@article{TekinAshikagaHorikawaetal.2018,
  author    = {Tekin, Nurettin and Ashikaga, Mitsugu and Horikawa, Atsushi and Funke, Harald},
  title     = {Enhancement of fuel flexibility of industrial gas turbines by development of innovative hydrogen combustion systems},
  series = {Gas for energy},
  journal   = {Gas for energy},
  number    = {2},
  publisher = {Vulkan-Verlag},
  address   = {Essen},
  pages     = {4},
  year      = {2018},
  abstract  = {For fuel flexibility enhancement hydrogen represents a possible alternative gas turbine fuel within future low emission power generation, in case of hydrogen production by the use of renewable energy sources such as wind energy or biomass. Kawasaki Heavy Industries, Ltd. (KHI) has research and development projects for future hydrogen society; production of hydrogen gas, refinement and liquefaction for transportation and storage, and utilization with gas turbine / gas engine for the generation of electricity. In the development of hydrogen gas turbines, a key technology is the stable and low NOx hydrogen combustion, especially Dry Low Emission (DLE) or Dry Low NOx (DLN) hydrogen combustion. Due to the large difference in the physical properties of hydrogen compared to other fuels such as natural gas, well established gas turbine combustion systems cannot be directly applied for DLE hydrogen combustion. Thus, the development of DLE hydrogen combustion technologies is an essential and challenging task for the future of hydrogen fueled gas turbines. The DLE Micro-Mix combustion principle for hydrogen fuel has been in development for many years to significantly reduce NOx emissions. This combustion principle is based on cross-flow mixing of air and gaseous hydrogen which reacts in multiple miniaturized "diffusion-type" flames. The major advantages of this combustion principle are the inherent safety against flashback and the low NOx-emissions due to a very short residence time of the reactants in the flame region of the micro-flames.},
  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 = {The Proceedings of the International Conference on Power Engineering (ICOPE)},
  booktitle = {The Proceedings of the International Conference on Power Engineering (ICOPE)},
  doi       = {10.1299/jsmeicope.2021.15.2021-0237},
  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{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 = {Conference Proceedings Turbo Expo: Power for Land, Sea and Air, Volume 3B: Combustion, Fuels, and Emissions},
  booktitle = {Conference Proceedings Turbo Expo: Power for Land, Sea and Air, 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 and Kishimoto, Tsuyoshi and Okada, Koichi},
  title     = {Experimental and numerical investigation on the effect of pressure on micromix hydrogen combustion},
  series = {Conference Proceedings Turbo Expo: Power for Land, Sea and Air, Volume 3A: Combustion, Fuels, and Emissions},
  booktitle = {Conference Proceedings Turbo Expo: Power for Land, Sea and Air, Volume 3A: Combustion, Fuels, and Emissions},
  publisher = {ASME},
  address   = {New York, NY},
  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}
}
@article{FunkeKeinzKustereretal.2016,
  author    = {Funke, Harald and Keinz, Jan and Kusterer, Karsten and Ayed, Anis Haj and Kazari, Masahide and Kitajima, Junichi and Horikawa, Atsushi and Okada, Kunio},
  title     = {Experimental and Numerical Study on Optimizing the Dry Low NOₓ Micromix Hydrogen Combustion Principle for Industrial Gas Turbine Applications},
  series = {Journal of Thermal Science and Engineering Applications},
  volume    = {9},
  journal   = {Journal of Thermal Science and Engineering Applications},
  number    = {2},
  publisher = {ASME},
  address   = {New York, NY},
  issn      = {1948-5093},
  doi       = {10.1115/1.4034849},
  pages     = {021001 -- 021001-10},
  year      = {2016},
  abstract  = {Combined with the use of renewable energy sources for its production, hydrogen represents a possible alternative gas turbine fuel for future low-emission power generation. Due to the difference in the physical properties of hydrogen compared to other fuels such as natural gas, well-established gas turbine combustion systems cannot be directly applied to dry low NOₓ (DLN) hydrogen combustion. The DLN micromix combustion of hydrogen has been under development for many years, since it has the promise to significantly reduce NOₓ emissions. This combustion principle for air-breathing engines is based on crossflow mixing of air and gaseous hydrogen. Air and hydrogen react in multiple miniaturized diffusion-type flames with an inherent safety against flashback and with low NOₓ emissions due to a very short residence time of the reactants in the flame region. The paper presents an advanced DLN micromix hydrogen application. The experimental and numerical study shows a combustor configuration with a significantly reduced number of enlarged fuel injectors with high-thermal power output at constant energy density. Larger fuel injectors reduce manufacturing costs, are more robust and less sensitive to fuel contamination and blockage in industrial environments. The experimental and numerical results confirm the successful application of high-energy injectors, while the DLN micromix characteristics of the design point, under part-load conditions, and under off-design operation are maintained. Atmospheric test rig data on NOₓ emissions, optical flame-structure, and combustor material temperatures are compared to numerical simulations and show good agreement. The impact of the applied scaling and design laws on the miniaturized micromix flamelets is particularly investigated numerically for the resulting flow field, the flame-structure, and NOₓ formation.},
  language  = {en}
}
@article{AyedKustererFunkeetal.2016,
  author    = {Ayed, Anis Haj and Kusterer, Karsten and Funke, Harald and Keinz, Jan},
  title     = {CFD Based Improvement of the DLN Hydrogen Micromix Combustion Technology at Increased Energy Densities},
  series = {American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS)},
  volume    = {26},
  journal   = {American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS)},
  number    = {3},
  publisher = {GSSRR},
  issn      = {2313-4402},
  pages     = {290 -- 303},
  year      = {2016},
  abstract  = {Combined with the use of renewable energy sources for its production, Hydrogen represents a possible alternative gas turbine fuel within future low emission power generation. Due to the large difference in the physical properties of Hydrogen compared to other fuels such as natural gas, well established gas turbine combustion systems cannot be directly applied for Dry Low NOx (DLN) Hydrogen combustion. Thus, the development of DLN combustion technologies is an essential and challenging task for the future of Hydrogen fuelled gas turbines. The DLN Micromix combustion principle for hydrogen fuel has been developed to significantly reduce NOx-emissions. This combustion principle is based on cross-flow mixing of air and gaseous hydrogen which reacts in multiple miniaturized diffusion-type flames. The major advantages of this combustion principle are the inherent safety against flash-back and the low NOx-emissions due to a very short residence time of reactants in the flame region of the micro-flames. The Micromix Combustion technology has been already proven experimentally and numerically for pure Hydrogen fuel operation at different energy density levels. The aim of the present study is to analyze the influence of different geometry parameter variations on the flame structure and the NOx emission and to identify the most relevant design parameters, aiming to provide a physical understanding of the Micromix flame sensitivity to the burner design and identify further optimization potential of this innovative combustion technology while increasing its energy density and making it mature enough for real gas turbine application. The study reveals great optimization potential of the Micromix Combustion technology with respect to the DLN characteristics and gives insight into the impact of geometry modifications on flame structure and NOx emission. This allows to further increase the energy density of the Micromix burners and to integrate this technology in industrial gas turbines.},
  language  = {en}
}
@article{FunkeBeckmannKeinzetal.2016,
  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 = {ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition Volume 4A: Combustion, Fuels and Emissions Seoul, South Korea, June 13-17, 2016},
  journal   = {ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition Volume 4A: Combustion, Fuels and Emissions Seoul, South Korea, June 13-17, 2016},
  publisher = {ASME},
  address   = {New York, NY},
  isbn      = {978-0-7918-4975-0},
  doi       = {10.1115/GT2016-56430},
  pages     = {12},
  year      = {2016},
  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. 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, CFD analyses are validated towards 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. For pure hydrogen combustion a one-step global reaction is applied using a hybrid Eddy-Break-up model that incorporates finite rate kinetics. The model is evaluated and compared to a detailed hydrogen combustion mechanism derived by Li et al. including 9 species and 19 reversible elementary reactions. Based on this mechanism, reduction of the computational effort is achieved by applying the Flamelet Generated Manifolds (FGM) method while the accuracy of the detailed reaction scheme is maintained. For hydrogen-rich syngas combustion (H₂-CO) numerical analyses based on a skeletal H₂/CO reaction mechanism derived by Hawkes et al. and a detailed reaction mechanism provided by Ranzi et al. are performed. The comparison between combustion models and the 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 Flamelet Generated Manifolds method proved to be generally suitable to reduce the computational effort while maintaining the accuracy of detailed chemistry. Especially for reaction mechanisms with a high number of species accuracy and computational effort can be balanced using the FGM model.},
  language  = {en}
}
@inproceedings{AyedStrieganKustereretal.2017,
  author    = {Ayed, Anis Haj and Striegan, Constantin J. D. and Kusterer, Karsten and Funke, Harald and Kazari, M. and Horikawa, Atsushi and Okada, Kunio},
  title     = {Automated design space exploration of the hydrogen fueled "Micromix" combustor technology},
  pages     = {1 -- 8},
  year      = {2017},
  abstract  = {Combined with the use of renewable energy sources for its production, Hydrogen represents a possible alternative gas turbine fuel for future low emission power generation. Due to its different physical properties compared to other fuels such as natural gas, well established gas turbine combustion systems cannot be directly applied for Dry Low NOx (DLN) Hydrogen combustion. This makes the development of new combustion technologies an essential and challenging task for the future of hydrogen fueled gas turbines. The newly developed and successfully tested "DLN Micromix" combustion technology offers a great potential to burn hydrogen in gas turbines at very low NOx emissions. Aiming to further develop an existing burner design in terms of increased energy density, a redesign is required in order to stabilise the flames at higher mass flows and to maintain low emission levels. For this purpose, a systematic design exploration has been carried out with the support of CFD and optimisation tools to identify the interactions of geometrical and design parameters on the combustor performance. Aerodynamic effects as well as flame and emission formation are observed and understood time- and cost-efficiently. Correlations between single geometric values, the pressure drop of the burner and NOx production have been identified as a result. This numeric methodology helps to reduce the effort of manufacturing and testing to few designs for single validation campaigns, in order to confirm the flame stability and NOx emissions in a wider operating condition field.},
  language  = {en}
}
@article{AyedKustererFunkeetal.2017,
  author    = {Ayed, Anis Haj and Kusterer, Karsten and Funke, Harald and Keinz, Jan and Bohn, D.},
  title     = {CFD based exploration of the dry-low-NOx hydrogen micromix combustion technology at increased energy densities},
  series = {Propulsion and Power Research},
  volume    = {6},
  journal   = {Propulsion and Power Research},
  number    = {1},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {2212-540X},
  doi       = {10.1016/j.jppr.2017.01.005},
  pages     = {15 -- 24},
  year      = {2017},
  language  = {en}
}
@inproceedings{FunkeBeckmannKeinzetal.2021,
  author    = {Funke, Harald and Beckmann, Nils and Keinz, Jan and Horikawa, Atsushi},
  title     = {30 years of dry low NOx micromix combustor research for hydrogen-rich fuels: an overview of past and present activities},
  series = {Conference Proceedings Turbo Expo: Power for Land, Sea and Air, Volume 4B: Combustion, Fuels, and Emissions},
  booktitle = {Conference Proceedings Turbo Expo: Power for Land, Sea and Air, Volume 4B: Combustion, Fuels, and Emissions},
  publisher = {ASME},
  address   = {New York, NY},
  isbn      = {978-0-7918-8413-3},
  doi       = {10.1115/GT2020-16328},
  pages     = {14 Seiten},
  year      = {2021},
  abstract  = {The paper presents an overview of the past and present of low-emission combustor research with hydrogen-rich fuels at Aachen University of Applied Sciences. In 1990, AcUAS started developing the Dry-Low-NOx Micromix combustion technology. Micromix reduces NOx emissions using jet-in-crossflow mixing of multiple miniaturized fuel jets and combustor air with an inherent safety against flashback. At first, pure hydrogen as fuel was investigated with lab-scale applications. Later, Micromix prototypes were developed for the use in an industrial gas turbine Honeywell/Garrett GTCP-36-300, proving low NOx characteristics during real gas turbine operation, accompanied by the successful definition of safety laws and control system modifications. Further, the Micromix was optimized for the use in annular and can combustors as well as for fuel-flexibility with hydrogen-methane-mixtures and hydrogen-rich syngas qualities by means of extensive experimental and numerical simulations. In 2020, the latest Micromix application will be demonstrated in a commercial 2 MW-class gas turbine can-combustor with full-scale engine operation. The paper discusses the advances in Micromix research over the last three decades.},
  language  = {en}
}
@misc{EickmannEschFunkeetal.2014,
  author    = {Eickmann, Matthias and Esch, Thomas and Funke, Harald and Abanteriba, Sylvester and Roosen, Petra},
  title     = {Biofuels in Aviation - Safety Implications of Bio-Ethanol Usage in General Aviation Aircraft},
  year      = {2014},
  abstract  = {Up in the clouds and above fuels and construction materials must be very carefully selected to ensure a smooth flight and touchdown. Out of around 38,000 single and dual-engined propeller aeroplanes, roughly a third are affected by a new trend in the fuel sector that may lead to operating troubles or even emergency landings: The admixture of bio-ethanol to conventional gasoline. Experiences with these fuels may be projected to alternative mixtures containing new components.},
  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}
}
@techreport{EschFunkeRoosen2010,
  author    = {Esch, Thomas and Funke, Harald and Roosen, Petra},
  title     = {SIoBiA - Safety Implications of Biofuels in Aviation},
  publisher = {EASA},
  address   = {K{\"o}ln},
  pages     = {279 Seiten},
  year      = {2010},
  abstract  = {Biofuels potentially interesting also for aviation purposes are predominantly liquid fuels produced from biomass. The most common biofuels today are biodiesel and bioethanol. Since diesel engines are rather rare in aviation this survey is focusing on ethanol admixed to gasoline products. The Directive 2003/30/EC of the European Parliament and the Council of May 8th 2003 on the promotion of the use of biofuels or other renewable fuels for transport encourage a growing admixture of biogenic fuel components to fossil automotive gasoline. Some aircraft models equipped with spark ignited piston engines are approved for operation with automotive gasoline, frequently called "MOGAS" (motor gasoline). The majority of those approvals is limited to MOGAS compositions that do not contain methanol or ethanol beyond negligible amounts. In the past years (bio-)MTBE or (bio-)ETBE have been widely used as blending component of automotive gasoline whilst the usage of low-molecular alcohols like methanol or ethanol has been avoided due to the handling problems especially with regard to the strong affinity for water. With rising mandatory bio-admixtures the conversion of the basic biogenic ethanol to ETBE, causing a reduction of energetic payoff, becomes more and more unattractive. Therefore the direct ethanol admixture is accordingly favoured. Due to the national enforcements of the directive 2003/30/EC more oxygenates produced from organic materials like bioethanol have started to appear in automotive gasolines already. The current fuel specification EN 228 already allows up to 3 \% volume per volume (v/v) (bio-)methanol or up to 5 \% v/v (bio-)ethanol as fuel components. This is also roughly the amount of biogenic components to comply with the legal requirements to avoid monetary penalties for producers and distributors of fuels. Since automotive fuel is cheaper than the common aviation gasoline (AVGAS), creates less problems with lead deposits in the engine, and in general produces less pollutants it is strongly favoured by pilots. But being designed for a different set of usage scenarios the use of automotive fuel with low molecular alcohols for aircraft operation may have adverse effects in aviation operation. Increasing amounts of ethanol admixtures impose various changes in the gasoline's chemical and physical properties, some of them rather unexpected and not within the range of flight experiences even of long-term pilots.},
  language  = {en}
}