@inproceedings{FunkeEschRoosen2009,
  author    = {Funke, Harald and Esch, Thomas and Roosen, Peter},
  title     = {Using motor gasoline for aircrafts - coping with growing bio-fuel-caused risks by understanding cause-effect relationship},
  series = {Fuels 2009 : mineral oil based and alternative fuels ; 7th international colloquium ; January 14 - 15, 2009},
  booktitle = {Fuels 2009 : mineral oil based and alternative fuels ; 7th international colloquium ; January 14 - 15, 2009},
  editor    = {Bartz, Wilfried J.},
  publisher = {Technische Akademie Esslingen (TAE)},
  address   = {Ostfildern},
  isbn      = {978-3-924813-75-8},
  pages     = {237 -- 244},
  year      = {2009},
  abstract  = {The utilisation of vehicle-oriented gasoline in general aviation is very desirable for both ecological and economical reasons, as well as for general considerations of availability. As of today vehicle fuels may be used if the respective engine and cell are certified for such an operation. For older planes a supplementary technical certificate is provided for gasoline mixtures with less than 1 \% v/v ethanol only, though. Larger admixtures of ethanol may lead to sudden engine malfunction and should be considered as considerable security risks. Major problems are caused by the partially ethanol non-withstanding materials, a necessarily changed stochiometric adjustment of the engine for varying ethanol shares and the tendency for phase separation in the presence of absorbed water. The concepts of the flexible fuel vehicles are only partially applicable in the view of air security.},
  language  = {en}
}
@article{RobinsonRoennaFunke2007,
  author    = {Robinson, A. E. and R{\"o}nna, Uwe and Funke, Harald},
  title     = {Testing of a 10 kW diffusive micro-mix combustor for hydrogen-fuelled micro-scale gas turbines},
  series = {International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications <7, 2007, Freiburg, Breisgau> ; PowerMEMS ; 7},
  journal   = {International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications <7, 2007, Freiburg, Breisgau> ; PowerMEMS ; 7},
  pages     = {225 -- 228},
  year      = {2007},
  language  = {en}
}
@article{BecretGrossenTrillaetal.2007,
  author    = {B{\´e}cret, P. and Grossen, J. and Trilla, J. and Robinson, A. and Bosschaerts, W. and Funke, Harald and Hendrick, P.},
  title     = {Testing and numerical study of a 10 kW hydrogen micro combustor},
  series = {International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications <7, 2007, Freiburg, Breisgau> ; PowerMEMS ; 7},
  journal   = {International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications <7, 2007, Freiburg, Breisgau> ; PowerMEMS ; 7},
  pages     = {367 -- 370},
  year      = {2007},
  language  = {en}
}
@inproceedings{FunkeKeinzBoerneretal.2016,
  author    = {Funke, Harald and Keinz, Jan and B{\"o}rner, S. and Hendrick, P. and Elsing, R.},
  title     = {Testing and analysis of the impact on engine cycle parameters and control system modifications using hydrogen or methane as fuel in an industrial gas turbine},
  series = {Progress in propulsion physics ; Volume 8},
  booktitle = {Progress in propulsion physics ; Volume 8},
  publisher = {EDP Sciences},
  address   = {o.O.},
  organization    = {European Conference for Aerospace Sciences <2013, M{\"u}nchen>},
  isbn      = {978-5-94588-191-4},
  doi       = {10.1051/eucass/201608409},
  pages     = {409 -- 426},
  year      = {2016},
  language  = {en}
}
@article{BohnFunkeGier1999,
  author    = {Bohn, D. and Funke, Harald and Gier, J.},
  title     = {Temperature jet development in a cross-over channel},
  series = {Third European Conference on Turbomachinery - fluid dynamics and thermodynamics : : 2 - 5 March 1999, Royal National Hotel, London, UK / organized by the Energy Transfer and Thermofluid Mechanics Group of the Institution of Mechanical Engineers (IMechE); with support and sponsorship from European Commission / Vol. B.},
  journal   = {Third European Conference on Turbomachinery - fluid dynamics and thermodynamics : : 2 - 5 March 1999, Royal National Hotel, London, UK / organized by the Energy Transfer and Thermofluid Mechanics Group of the Institution of Mechanical Engineers (IMechE); with support and sponsorship from European Commission / Vol. B.},
  publisher = {Professional Engineering Publ.},
  address   = {Bury St. Edmunds},
  pages     = {671 -- 680},
  year      = {1999},
  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}
}
@article{FunkeEschRoosen2022,
  author    = {Funke, Harald and Esch, Thomas and Roosen, Petra},
  title     = {Powertrain Adaptions for LPG Usage in General Aviation},
  series = {MTZ worldwide},
  volume    = {2022},
  journal   = {MTZ worldwide},
  number    = {83},
  publisher = {Springer Nature},
  address   = {Basel},
  doi       = {10.1007/s38313-021-0756-6},
  pages     = {58 -- 62},
  year      = {2022},
  abstract  = {In general aviation, too, it is desirable to be able to operate existing internal combustion engines with fuels that produce less CO₂ than Avgas 100LL being widely used today It can be assumed that, in comparison, the fuels CNG, LPG or LNG, which are gaseous under normal conditions, produce significantly lower emissions. Necessary propulsion system adaptations were investigated as part of a research project at Aachen University of Applied Sciences.},
  language  = {en}
}
@article{FunkeReckerBosschaertsetal.2011,
  author    = {Funke, Harald and Recker, E. and Bosschaerts, W. and Boonen, Q. and B{\"o}rner, Sebastian},
  title     = {Parametrical study of the „Micromix" hydrogen combustion principle},
  series = {10th International Symposium on Experimental and Computational Aerothermodynamics of Internal Flows, ISAIF10-049, Brussels, Belgium, 4-7 July 2011},
  journal   = {10th International Symposium on Experimental and Computational Aerothermodynamics of Internal Flows, ISAIF10-049, Brussels, Belgium, 4-7 July 2011},
  year      = {2011},
  language  = {en}
}
@inproceedings{FunkeHajAyedKustereretal.2014,
  author    = {Funke, Harald and Haj Ayed, A. and Kusterer, K. and Keinz, Jan and Kazari, M. and Kitajima, J. and Horikawa, A. and Okada, K.},
  title     = {Numerical Study on Increased Energy Density for the DLN Micromix Hydrogen Combustion Principle},
  series = {Combustion, Fuels and Emissions (ASME Turbo Expo 2014: Turbine Technical Conference and Exposition : D{\"u}sseldorf, Germany, June 16-20, 2014 ; Vol. 4A)},
  booktitle = {Combustion, Fuels and Emissions (ASME Turbo Expo 2014: Turbine Technical Conference and Exposition : D{\"u}sseldorf, Germany, June 16-20, 2014 ; Vol. 4A)},
  publisher = {ASME},
  address   = {New York, N.Y.},
  isbn      = {978-0-7918-4568-4},
  pages     = {V04AT04A057},
  year      = {2014},
  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{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{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{BohnFunkeGier1999,
  author    = {Bohn, D. and Funke, Harald and Gier, J.},
  title     = {Numerical and Experimental Investigations on the Flow in a 4-Stage Turbine with Special Focus on the Development of a Radial Temperature Streak},
  series = {ASME Turbo Expo 1999, Indianapolis, USA, 1999},
  journal   = {ASME Turbo Expo 1999, Indianapolis, USA, 1999},
  year      = {1999},
  language  = {en}
}
@article{BohnFunkeSuerkenetal.2001,
  author    = {Bohn, Dieter and Funke, Harald and S{\"u}rken, Norbert and Kreitmeier, F.},
  title     = {Numerical and experimental investigations on endwall contouring in a four-stage turbine},
  series = {ASME Turbo Expo Land Sea \& Air 2001 : June 4 - 8, 2001, New Orleans, Louisiana / IGTI, International Gas Turbine Institute. American Society of Mechanical Engineers. International Gas Turbine Institute ..},
  journal   = {ASME Turbo Expo Land Sea \& Air 2001 : June 4 - 8, 2001, New Orleans, Louisiana / IGTI, International Gas Turbine Institute. American Society of Mechanical Engineers. International Gas Turbine Institute ..},
  publisher = {ASME},
  address   = {New York, NY},
  isbn      = {0-7918-3528-6},
  pages     = {CD-Rom},
  year      = {2001},
  language  = {en}
}
@article{BohnFunkeHeueretal.2000,
  author    = {Bohn, Dieter and Funke, Harald and Heuer, Tom and B{\"u}tikofer, J.},
  title     = {Numerical and experimental investigations of the influence of different swirl-ratios on the temperature streak equalization in a 4-stage turbine},
  series = {ASME Turbo Expo 2000 ; Munich, May 8-11 2000},
  journal   = {ASME Turbo Expo 2000 ; Munich, May 8-11 2000},
  address   = {Munich},
  year      = {2000},
  language  = {en}
}
@article{RobinsonFunkeWagemakersetal.2009,
  author    = {Robinson, A. E. and Funke, Harald and Wagemakers, R. and Grossen, J. and Bosschaerts, W. and Hendrick, P.},
  title     = {Numerical and Experimental Investigation of a Micromix Combustor for a Hydrogen Fuelled μ-Scale Gas Turbine},
  series = {Proceedings of the ASME Turbo Expo 2009 : : presented at the 2009 ASME Turbo Expo, June 8 - 12, 2009, Orlando, Florida, USA / sponsored by the International Gas Turbine Institute},
  journal   = {Proceedings of the ASME Turbo Expo 2009 : : presented at the 2009 ASME Turbo Expo, June 8 - 12, 2009, Orlando, Florida, USA / sponsored by the International Gas Turbine Institute},
  publisher = {ASME},
  address   = {New York, NY},
  isbn      = {9780791848869},
  pages     = {253 -- 262},
  year      = {2009},
  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{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{FunkeBoernerKeinzetal.2012,
  author    = {Funke, Harald and B{\"o}rner, Sebastian and Keinz, Jan and Kusterer, K. and Kroninger, D. and Kitajima, J. and Kazari, M. and Horikama, A.},
  title     = {Numerical and experimental characterization of low NOx Micromix combustion principle for industrial hydrogen gas turbine applications},
  series = {Proceedings of ASME Turbo Expo 2012},
  booktitle = {Proceedings of ASME Turbo Expo 2012},
  pages     = {11},
  year      = {2012},
  language  = {en}
}
@incollection{FunkeBoernerHendricketal.2011,
  author    = {Funke, Harald and B{\"o}rner, Sebastian and Hendrick, P. and Recker, E.},
  title     = {Modification and testing of an engine and fuel control system for a hydrogen fuelled gas turbine},
  series = {Progress in Propulsion Physics. Vol. 2},
  booktitle = {Progress in Propulsion Physics. Vol. 2},
  publisher = {EDP Sciences},
  address   = {Les Ulis},
  isbn      = {978-2-7598-0673-7},
  pages     = {475 -- 486},
  year      = {2011},
  language  = {en}
}
@inproceedings{FunkeBoernerKeinzetal.2012,
  author    = {Funke, Harald and B{\"o}rner, Sebastian and Keinz, Jan and Hendrick, P. and Recker, E.},
  title     = {Low NOx Hydrogen combustion chamber for industrial gas turbine applications", 14th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery},
  series = {ISROMAC-14 : the Forteenth International Symposium on Transport Phenomena and Dynamics of Rotating Machinery ; Honolulu, Hawaii, February 27 - March 02nd, 2012},
  booktitle = {ISROMAC-14 : the Forteenth International Symposium on Transport Phenomena and Dynamics of Rotating Machinery ; Honolulu, Hawaii, February 27 - March 02nd, 2012},
  year      = {2012},
  language  = {en}
}
@article{FunkeBoernerRobinsonetal.2010,
  author    = {Funke, Harald and B{\"o}rner, Sebastian and Robinson, A. and Hendrick, P. and Recker, E.},
  title     = {Low NOx H2 combustion for industrial gas turbines of various power ranges},
  series = {5th International Gas Turbine Conference ETN-IGTC, ETN-2010-42, Brussels, Belgium, October 2010},
  journal   = {5th International Gas Turbine Conference ETN-IGTC, ETN-2010-42, Brussels, Belgium, October 2010},
  year      = {2010},
  language  = {en}
}
@inproceedings{BoernerFunkeHendricketal.2009,
  author    = {B{\"o}rner, Sebastian and Funke, Harald and Hendrick, P. and Recker, E.},
  title     = {LES of Jets In Cross-Flow and Application to the "Micromix" Hydrogen Combustion},
  series = {XIX International Symposium on Air Breathing Engines 2009 (ISABE 2009) : Proceedings of a meeting held 7-11 September 2009, Montreal, Canada},
  booktitle = {XIX International Symposium on Air Breathing Engines 2009 (ISABE 2009) : Proceedings of a meeting held 7-11 September 2009, Montreal, Canada},
  isbn      = {9781615676064},
  pages     = {1555 -- 1561},
  year      = {2009},
  language  = {en}
}
@article{HajAyedKustererFunkeetal.2015,
  author    = {Haj Ayed, A. and Kusterer, K. and Funke, Harald and Keinz, Jan and Striegan, Constantin and Bohn, D.},
  title     = {Improvement study for the dry-low-NOx hydrogen micromix combustion technology},
  series = {Propulsion and power research},
  volume    = {Vol. 4},
  journal   = {Propulsion and power research},
  number    = {Iss. 3},
  issn      = {2212-540X},
  doi       = {10.1016/j.jppr.2015.07.003},
  pages     = {132 -- 140},
  year      = {2015},
  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. Boston, Massachusetts, USA. June 26-30, 2023},
  booktitle = {Proceedings of the ASME Turbo Expo 2023: Turbomachinery Technical Conference and Exposition. Volume 1: Aircraft Engine. Boston, Massachusetts, USA. June 26-30, 2023},
  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}
}
@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}
}
@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}
}
@article{FunkeBeckmann2022,
  author    = {Funke, Harald and Beckmann, Nils},
  title     = {Flexible fuel operation of a Dry-Low-NOx Micromix Combustor with Variable Hydrogen Methane Mixture},
  series = {International Journal of Gas Turbine, Propulsion and Power Systems},
  volume    = {13},
  journal   = {International Journal of Gas Turbine, Propulsion and Power Systems},
  number    = {2},
  issn      = {1882-5079},
  pages     = {1 -- 7},
  year      = {2022},
  abstract  = {The role of hydrogen (H2) as a carbon-free energy carrier is discussed since decades for reducing greenhouse gas emissions. As bridge technology towards a hydrogen-based energy supply, fuel mixtures of natural gas or methane (CH4) and hydrogen are possible. The paper presents the first test results of a low-emission Micromix combustor designed for flexible-fuel operation with variable H2/CH4 mixtures. The numerical and experimental approach for considering variable fuel mixtures instead of recently investigated pure hydrogen is described. In the experimental studies, a first generation FuelFlex Micromix combustor geometry is tested at atmospheric pressure at gas turbine operating conditions corresponding to part- and full-load. The H2/CH4 fuel mixture composition is varied between 57 and 100 vol.\% hydrogen content. Despite the challenges flexible-fuel operation poses onto the design of a combustion system, the evaluated FuelFlex Micromix prototype shows a significant low NOx performance},
  language  = {en}
}
@article{ReckerBosschaertsWagemakersetal.2010,
  author    = {Recker, Elmar and Bosschaerts, Walter and Wagemakers, Rolf and Hendrick, Patrick and Funke, Harald and B{\"o}rner, Sebastian},
  title     = {Experimental study of a round jet in cross-flow at low momentum ratio},
  series = {15th International Symposium on Applications of Laser Techniques to Fluid Mechanics Lisbon, Portugal, 05-08 July, 2010 - 1},
  journal   = {15th International Symposium on Applications of Laser Techniques to Fluid Mechanics Lisbon, Portugal, 05-08 July, 2010 - 1},
  pages     = {1 -- 13},
  year      = {2010},
  language  = {en}
}
@article{BohnFunke2003,
  author    = {Bohn, Dieter and Funke, Harald},
  title     = {Experimental investigations into the nonuniform flow in a 4-stage turbine with special focus on the flow equalization in the first turbine stage},
  series = {ASME TURBO EXPO, Proceedings of the ASME Turbo Expo, 2003},
  journal   = {ASME TURBO EXPO, Proceedings of the ASME Turbo Expo, 2003},
  isbn      = {0-7918-3689-4},
  pages     = {281 -- 289},
  year      = {2003},
  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{FunkeBoernerKrebsetal.2011,
  author    = {Funke, Harald and B{\"o}rner, Sebastian and Krebs, W. and Wolf, E.},
  title     = {Experimental Characterization of Low NOx Micromix Prototype Combustors for Industrial Gas Turbine Applications},
  series = {ASME Turbo Expo 2011 ; Vancouver, Canada, June 6-10, 2011},
  journal   = {ASME Turbo Expo 2011 ; Vancouver, Canada, June 6-10, 2011},
  year      = {2011},
  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}
}
@inproceedings{FunkeKeinzKustereretal.2015,
  author    = {Funke, Harald and Keinz, Jan and Kusterer, K. and Haj Ayed, A. and Kazari, M. and Kitajima, J. and Horikawa, A. and Okada, K.},
  title     = {Experimental and Numerical Study on Optimizing the DLN Micromix Hydrogen Combustion Principle for Industrial Gas Turbine Applications},
  series = {ASME Turbo Expo 2015: Turbine Technical Conference and Exposition Volume 4A: Combustion, Fuels and Emissions Montreal, Quebec, Canada, June 15-19, 2015},
  booktitle = {ASME Turbo Expo 2015: Turbine Technical Conference and Exposition Volume 4A: Combustion, Fuels and Emissions Montreal, Quebec, Canada, June 15-19, 2015},
  isbn      = {978-0-7918-5668-0},
  doi       = {10.1115/GT2015-42043},
  pages     = {V04AT04A008},
  year      = {2015},
  language  = {en}
}
@article{FunkeDickhoffKeinzetal.2014,
  author    = {Funke, Harald and Dickhoff, J. and Keinz, Jan and Anis, H. A. and Parente, A. and Hendrick, P.},
  title     = {Experimental and numerical study of the micromix combustion principle applied for hydrogen and hydrogen-rich syngas as fuel with increased energy density for industrial gas turbine applications},
  series = {Energy procedia},
  journal   = {Energy procedia},
  number    = {61},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1876-6102 (E-Journal)},
  doi       = {10.1016/j.egypro.2014.12.201},
  pages     = {1736 -- 1739},
  year      = {2014},
  abstract  = {The Dry Low NOx (DLN) Micromix combustion principle with increased energy density is adapted for the industrial gas turbine APU GTCP 36-300 using hydrogen and hydrogen-rich syngas with a composition of 90\%-Vol. hydrogen (H₂) and 10\%-Vol. carbon-monoxide (CO). Experimental and numerical studies of several combustor geometries for hydrogen and syngas show the successful advance of the DLN Micromix combustion from pure hydrogen to hydrogen-rich syngas. The impact of the different fuel properties on the combustion principle and aerodynamic flame stabilization design laws, flow field, flame structure and emission characteristics is investigated by numerical analysis using a hybrid Eddy Break Up combustion model and validated against experimental results.},
  language  = {en}
}
@article{HajAyedKustererFunkeetal.2015,
  author    = {Haj Ayed, A. and Kusterer, K. and Funke, Harald and Keinz, Jan and Striegan, Constantin and Bohn, D.},
  title     = {Experimental and numerical investigations of the dry-low-NOx hydrogen micromix combustion chamber of an industrial gas turbine},
  series = {Propulsion and power research},
  volume    = {Vol. 4},
  journal   = {Propulsion and power research},
  number    = {Iss. 3},
  issn      = {2212-540X},
  doi       = {10.1016/j.jppr.2015.07.005},
  pages     = {123 -- 131},
  year      = {2015},
  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 = {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{FunkeKeinzBoerneretal.2013,
  author    = {Funke, Harald and Keinz, Jan and B{\"o}rner, Sebastian and Haj Ayed, A. and Kusterer, K. and Tekin, N. and Kazari, M. and Kitajima, J. and Horikawa, A. and Okada, K.},
  title     = {Experimental and numerical characterization of the dry low NOx micromix hydrogen combustion principle at increased energy density for industrial hydrogen gas turbine applications},
  series = {Combustion, fuels and emissions : proceedings of the ASME Turbo Expo: Turbine Technical Conference and Exposition - 2013 ; June 3 - 7, 2013, San Antonio, Texas, USA ; vol. 1},
  booktitle = {Combustion, fuels and emissions : proceedings of the ASME Turbo Expo: Turbine Technical Conference and Exposition - 2013 ; June 3 - 7, 2013, San Antonio, Texas, USA ; vol. 1},
  editor    = {Song, Seung Jin},
  publisher = {ASME},
  address   = {New York, NY},
  organization    = {American Society of Mechanical Engineers},
  isbn      = {978-0-7918-5510-2},
  pages     = {V001T04A055},
  year      = {2013},
  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{HorikawaKazariOkadaetal.2015,
  author    = {Horikawa, Atsushi and Kazari, Masahide and Okada, Kunio and Funke, Harald and Keinz, Jan and Kusterer, Karsten and Haji Ayed, Anis},
  title     = {Developments of Hydrogen Dry Low Emission Combustion Technology},
  series = {Annual Congress of Gas Turbine Society Japan, 2015},
  booktitle = {Annual Congress of Gas Turbine Society Japan, 2015},
  pages     = {5 S.},
  year      = {2015},
  language  = {en}
}
@article{FunkeRobinson2007,
  author    = {Funke, Harald and Robinson, A. E.},
  title     = {Development of a new test rig for a micro scale hydrogen combustion chamber},
  series = {Proceedings of the 2nd European Conference for Aero-Space Sciences : July 1 - 6, 2007, Brussels, Belgium},
  journal   = {Proceedings of the 2nd European Conference for Aero-Space Sciences : July 1 - 6, 2007, Brussels, Belgium},
  publisher = {-},
  pages     = {1 -- 8},
  year      = {2007},
  language  = {en}
}
@article{RobinsonFunkeHendricketal.2008,
  author    = {Robinson, A. E. and Funke, Harald and Hendrick, P. and Recker, E. and Peirs, J.},
  title     = {Development of a hydrogen fuelled 1 kW ultra micro gas turbine with special respect to designing, testing and mapping of the µ-scale combustor},
  series = {IEEE International Conference on Sustainable Energy Technologies, 2008 : ICSET 2008 ; Singapore, 24 - 27 Nov. 2008.},
  journal   = {IEEE International Conference on Sustainable Energy Technologies, 2008 : ICSET 2008 ; Singapore, 24 - 27 Nov. 2008.},
  publisher = {IEEE},
  address   = {Piscataway, NJ},
  isbn      = {978-1-4244-1887-9},
  pages     = {656 -- 660},
  year      = {2008},
  language  = {en}
}
@article{TrillaGrossenRobinsonetal.2008,
  author    = {Trilla, Joan and Grossen, J{\"u}rgen and Robinson, Alexander and Funke, Harald and Bosschaerts, Walter and Hendrick, Patrick},
  title     = {Development of a hydrogen combustion chamber for an ultra micro gas turbine},
  series = {PowerMEMS 2008, 8th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications, microEMS 2008, 2nd Symposium on Micro Environmental Machine Systems, Sendai, JP, Nov 9-12, 2008},
  journal   = {PowerMEMS 2008, 8th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications, microEMS 2008, 2nd Symposium on Micro Environmental Machine Systems, Sendai, JP, Nov 9-12, 2008},
  pages     = {101 -- 104},
  year      = {2008},
  language  = {en}
}
@inproceedings{FunkeKeinzHajAyedetal.2015,
  author    = {Funke, Harald and Keinz, Jan and Haj Ayed, A. and Kazari, M. and Kitajima, J. and Horikawa, A. and Okada, K.},
  title     = {Development and Testing of a Low NOx Micromix Combustion Chamber for an Industrial Gas Turbine},
  series = {Proceedings of International Gas Turbine Congress 2015 Tokyo November 15-20, 2015, Tokyo, Japan},
  booktitle = {Proceedings of International Gas Turbine Congress 2015 Tokyo November 15-20, 2015, Tokyo, Japan},
  isbn      = {978-4-89111-008-6},
  pages     = {131 -- 140},
  year      = {2015},
  language  = {en}
}
@inproceedings{FunkeBeckmannAbanteriba2019,
  author    = {Funke, Harald and Beckmann, Nils and Abanteriba, Sylvester},
  title     = {Development and Testing of a FuelFlex Dry-Low-NOx Micromix Combustor for Industrial Gas Turbine Applications With Variable Hydrogen Methane Mixtures},
  series = {ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. June 17-21, 2019 Phoenix, Arizona, USA. Volume 4A: Combustion, Fuels, and Emissions},
  booktitle = {ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. June 17-21, 2019 Phoenix, Arizona, USA. Volume 4A: Combustion, Fuels, and Emissions},
  isbn      = {978-0-7918-5861-5},
  doi       = {10.1115/GT2019-90095},
  pages     = {11 Seiten},
  year      = {2019},
  language  = {en}
}
@article{FunkeRoennaRobinson2008,
  author    = {Funke, Harald and R{\"o}nna, Uwe and Robinson, A. E.},
  title     = {Development and testing of a 10 kW diffusive micromix combustor for hydrogen-fuelled μ-scale gas turbines},
  series = {Proceedings of ASME Turbo Expo 2008: Power for Land, Sea and Air ; GT2008 ; June 9-13, 2008, Berlin, Germany},
  journal   = {Proceedings of ASME Turbo Expo 2008: Power for Land, Sea and Air ; GT2008 ; June 9-13, 2008, Berlin, Germany},
  publisher = {ASME},
  address   = {New York, NY},
  pages     = {1 -- 8},
  year      = {2008},
  language  = {en}
}
@inproceedings{FunkeBoernerHendricketal.2013,
  author    = {Funke, Harald and B{\"o}rner, Sebastian and Hendrick, P. and Recker, E. and Elsing, R.},
  title     = {Development and integration of a scalable low NOx combustion chamber for a hydrogen fuelled aero gas turbine},
  series = {Progress in Propulsion Physics. - Vol. 4},
  booktitle = {Progress in Propulsion Physics. - Vol. 4},
  editor    = {DeLuca, Luigi T.},
  publisher = {EDP Sciences},
  address   = {[Les Ulis]},
  isbn      = {978-2-7598-0876-2},
  doi       = {10.1051/eucass/201304357},
  pages     = {357 -- 372},
  year      = {2013},
  language  = {en}
}
@article{FunkeRobinsonHendricketal.2010,
  author    = {Funke, Harald and Robinson, A. E. and Hendrick, P. and Wagemakers, R.},
  title     = {Design and Testing of a Micromix Combustor With Recuperative Wall Cooling for a Hydrogen Fuelled µ-Scale Gas Turbine},
  series = {Proceedings of the ASME Turbo Expo 2010 : presented at the 2010 ASME Turbo Expo, June 14 - 18, 2010, Glasgow, UK / sponsored by the International Gas Turbine Institute / Vol. 5: Industrial and cogeneration ; microturbines and small turbomachinery ; oil and gas applications ; wind turbine technology},
  journal   = {Proceedings of the ASME Turbo Expo 2010 : presented at the 2010 ASME Turbo Expo, June 14 - 18, 2010, Glasgow, UK / sponsored by the International Gas Turbine Institute / Vol. 5: Industrial and cogeneration ; microturbines and small turbomachinery ; oil and gas applications ; wind turbine technology},
  publisher = {ASME},
  address   = {New York, NY},
  isbn      = {978-0-7918-4400-7},
  pages     = {587 -- 596},
  year      = {2010},
  language  = {en}
}
@article{RobinsonFunkeHendrick2011,
  author    = {Robinson, A. E. and Funke, Harald and Hendrick, P.},
  title     = {Design and Testing of a Micromix Combustor With Recuperative Wall Cooling for a Hydrogen Fueled µ-Scale Gas Turbine},
  series = {Journal of engineering for gas turbines and power},
  volume    = {133},
  journal   = {Journal of engineering for gas turbines and power},
  number    = {8},
  publisher = {ASME},
  address   = {New York},
  isbn      = {1528-8919},
  pages     = {Art. Nr. 082301 , 8 Seiten},
  year      = {2011},
  language  = {en}
}
@article{BoernerFunkeHendricketal.2010,
  author    = {B{\"o}rner, Sebastian and Funke, Harald and Hendrick, P. and Recker, E.},
  title     = {Control system modifications for a hydrogen fuelled gas-turbine},
  series = {ISROMAC 13, 13th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery, Honolulu, HI, US, Apr 4-7, 2010},
  journal   = {ISROMAC 13, 13th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery, Honolulu, HI, US, Apr 4-7, 2010},
  publisher = {Curran},
  address   = {Red Hook, NY},
  isbn      = {978-1-617-38848-4},
  pages     = {665 -- 670},
  year      = {2010},
  language  = {en}
}