@misc{KoenigMischkePohletal., author = {K{\"o}nig, Paul and Mischke, Marcel and Pohl, Michael and Kazula, Stefan and H{\"o}schler, Klaus}, title = {Concept Development and Evaluation for a Broadband Noise Absorbing Acoustic Liner Concept for Aviation}, series = {24th International Society For Air Breathing Engines (ISABE-2019-24261), 22.-27. September 2019}, journal = {24th International Society For Air Breathing Engines (ISABE-2019-24261), 22.-27. September 2019}, abstract = {This paper presents design adaptations during the further development of innovative broadband acoustic liner concepts (Foil Helmholtz Resonator Liner; FHR-Liners) which utilise flexible foils within a honeycomb structure to attenuate engine and aircraft noise. The requirements for acoustic liners in aviation are described and utilised to derive evaluation criteria. Modifications of the FHR-Liner concept are introduced. A suitable concept evaluation method based on VDI 2225 is applied to evaluate the modified liner concepts concerning the main evaluation criteria.}, language = {en} } @misc{KazulaWoellnerGrasseltetal., author = {Kazula, Stefan and W{\"o}llner, Mark and Grasselt, David and H{\"o}schler, Klaus}, title = {Ideal Geometries and Potential Benefit of Variable Pitot Inlets for Subsonic and Supersonic Business Aviation}, series = {8TH EUROPEAN CONFERENCE FOR AERONAUTICS AND SPACE SCIENCES (EUCASS)}, journal = {8TH EUROPEAN CONFERENCE FOR AERONAUTICS AND SPACE SCIENCES (EUCASS)}, doi = {10.13009/EUCASS2019-314}, abstract = {The challenge of determining ideal inlet geometries for variable pitot aero engine inlets in transonic and supersonic civil aviation is presented. The trade-off in inlet design and the geometric inlet parameters are introduced. By means of a parametric design study, feasible inlet geometries for variable inlets are identified and the potential aerodynamic benefit of using variable pitot inlets for flight speeds from Mach 0.95, 1.3 up to 1.6 is examined. After considering the additional weight of variable inlets, for instance due to required actuators, a remaining range benefit of over 20\% at a flight speed of Mach 1.6 is determined.}, language = {en} } @misc{MischkeKazulaHoeschler, author = {Mischke, Marcel and Kazula, Stefan and H{\"o}schler, Klaus}, title = {Preliminary Safety Assessment on System Design Level for Broadband Acoustic Liner Concepts for Aviation}, series = {Proceedings of the 9th EASN International Conference on Innovation in Aviation \& Space}, journal = {Proceedings of the 9th EASN International Conference on Innovation in Aviation \& Space}, address = {Athen}, doi = {10.1051/matecconf/201930404010}, pages = {8}, abstract = {Selected methods of the aviation safety assessment process according to ARP 4761 are introduced and conducted within the scope of a concept study for future broadband acoustic liners. While having similar primary functions and basic design, the acoustic liner concepts diverge concerning subfunctions and potential malfunctions. With the ARP 4761 safety assessment methods, significant differences in sub functions and possible malfunctions of the concepts can be identified. The results of the safety assessment are discussed, and the concepts are evaluated in terms of feasibility and safety.}, language = {en} } @misc{YagciHoeschlerPannieretal., author = {Yagci, Tolga and H{\"o}schler, Klaus and Pannier, Stephan and Ende, Sven von}, title = {A Structural Health Monitoring (SHM) approach using a multidisciplinary digital twin for high-pressure turbine discs in civil aviation}, series = {Proceedings IRF2020 : 7th International Conference Integrity-Reliability-Failur, Funchal/Portugal, 6-10 Sep 2020}, journal = {Proceedings IRF2020 : 7th International Conference Integrity-Reliability-Failur, Funchal/Portugal, 6-10 Sep 2020}, editor = {Silva Gomes, J. F. and Meguid, Shaker A.}, isbn = {978-989-54756-1-2}, pages = {491 -- 502}, abstract = {The health status of an aircraft rotating turbine component depends heavily on the flight profiles flown by the operator. In contrast of this dependency, the declared Low Cycle Fatigue (LCF) life is typically determined for a designed flight profile, which is representative for most fleet flight profiles. A significant improvement in component utilisation without compromising safety can be achieved by using Engine Health Monitoring (EHM) data in order to monitor the LCF life by means of a digital engine twin. This paper is focussed on the development of a digital twin for a Civil Small and Medium Engine (CSME) and the structural health monitoring (SHM) of LCF life. The digital twin combines analytical models from multiple disciplines such as system performance, thermals and structures and aims to connect operational data to the component's accumulated damage. This enables individual monitoring of the component's health status, and prediction of Remaining Useful Life (RUL).}, language = {en} } @misc{KazulaHoeschler, author = {Kazula, Stefan and H{\"o}schler, Klaus}, title = {Evaluation of variable pitot inlet concepts for transonic and supersonic civil aviation}, series = {Aircraft Engineering and Aerospace Technology}, volume = {92}, journal = {Aircraft Engineering and Aerospace Technology}, number = {6}, issn = {0002-2667}, doi = {10.1108/AEAT-11-2019-0225}, pages = {807 -- 815}, abstract = {Purpose - This paper aims to describe the selection of the ideal variable inlet concept group by using results of aerodynamic investigations, system safety analyses and integration studies. Design/methodology/approach - Aerodynamic and functional inlet requirements are explained and variable inlet concept groups are introduced. The concept evaluation by means of a weighted point rating is presented. The respective concept groups are analysed and evaluated regarding economic, functional and safety requirements. Findings - By means of this evaluation, the concept group that adjusts the inlet geometry by rigid segment repositioning is identified as most suitable concept group. Originality/value - The early selection of the most suitable concept group enables more detailed subsequent concept investigations, potentially enabling the technology of variable inlets for future commercial aircraft.}, language = {en} } @misc{KazulaWoellnerHoeschler, author = {Kazula, Stefan and W{\"o}llner, Mark and H{\"o}schler, Klaus}, title = {Identification of efficient geometries for variable pitot inlets for supersonic transport}, series = {Aircraft Engineering and Aerospace Technology}, volume = {92}, journal = {Aircraft Engineering and Aerospace Technology}, number = {7}, issn = {0002-2667}, doi = {10.1108/AEAT-11-2019-0228}, pages = {981 -- 992}, abstract = {Purpose - This paper aims to reveal the influence of selected geometric parameters on the aerodynamic performance of circular variable aero engine inlets in transonic and supersonic civil aviation. Design/methodology/approach - The trade-off in inlet design and aerodynamic evaluation parameters is presented. The approach to investigate the dependencies between the aerodynamic and geometric parameters at different flight conditions by means of a parametric design study is introduced. Findings - The dependencies of inlet drag and efficiency from geometric parameters at flight speeds of Mach 0.95 up to Mach 1.6 are identified. Although entailing additional weight, the inlet length represents the parameter with the highest potential for drag reduction by up to 50\% in the selected design space. Ideal geometries for variable pitot inlets are determined. After considering weight, their potential range benefit nearly disappears for subsonic applications, but remains above 20\% for supersonic flight at Mach 1.6. Originality/value - Hence, the technology of circular variable pitot inlets for supersonic transport aircraft could be a way to achieve the ambitious ecological, safety and economic goals for future civil aviation.}, language = {en} } @misc{KazulaHoeschler, author = {Kazula, Stefan and H{\"o}schler, Klaus}, title = {Review of Variable Leading Edge Patents for Aircraft Wings and Engine Inlets and Their Relevance for Variable Pitot Inlets in Future Supersonic Transport}, series = {Deutscher Luft- und Raumfahrtkongress 2020, Online, 1. bis 3. September 2020}, journal = {Deutscher Luft- und Raumfahrtkongress 2020, Online, 1. bis 3. September 2020}, abstract = {The motivation for designing variable pitot inlets for future supersonic transport (SST) is explained. A comprehensive overview of existing technological solutions for variable leading edges of aircraft wings and engines inlets is given. The advantages and limitations of over 80 solutions, as well as their relevance for application on variable pitot inlets for SST are analysed. These analyses emphasis challenges of existing solution options concerning design methodologies, level of detail and experience with a technology.}, language = {en} } @misc{KazulaHoeschler, author = {Kazula, Stefan and H{\"o}schler, Klaus}, title = {A Variable Pitot-Inlet Concept for Supersonic Aviation}, series = {Global Power \& Propulsion Society GPPS Chania20, Online, 7th - 9th September 2020}, journal = {Global Power \& Propulsion Society GPPS Chania20, Online, 7th - 9th September 2020}, issn = {2504-4400}, doi = {10.33737/gpps20-tc-49}, pages = {10}, abstract = {An overview of aero-engine inlets, the design process in aviation and a safe design approach for academic studies is provided. By means of a safe design approach, a variable inlet concept is developed up to technology readiness level (TRL) 3 and described. The application of safety and reliability methods, aerodynamic and structural analyses, as well as functional demonstrators proves the feasibility of the present variable inlet concept and highlights its potential for application in future supersonic transport (SST).}, language = {en} } @misc{MischkePohlHoeschleretal., author = {Mischke, Marcel and Pohl, Michael and H{\"o}schler, Klaus and Huppertz, Andr{\ยดe}}, title = {A Holistic Approach for the Generic Preliminary Design of Axial Compressor and Turbine Annulus Contours}, series = {Conference Paper of the DLRK 2020}, volume = {Deutscher Luft- und Raumfahrtkongress 2020}, journal = {Conference Paper of the DLRK 2020}, publisher = {Deutsche Gesellschaft f{\"u}r Luft- und Raumfahrt - Lilienthal-Oberth e.V.}, address = {Bonn}, doi = {https://doi.org/10.25967/530097}, url = {http://nbn-resolving.de/urn:nbn:de:101:1-2020121112463561159960}, pages = {12}, abstract = {An essential aspect in the whole engine modelling of modern aircraft engines is the preliminary design of the meridional gas path definition. Especially the annulus dimensioning and topological characterisation of engine core subsystems are usually time-consuming. This paper presents a holistic and parametric approach to predesign the geometric 2D annulus contours of compressor and turbine subsystems without complex thermodynamic calculations. It is based on distribution functions of the axial and radial dimensions, as well as the variations of compressor and turbine stages and realises a time-efficient re-dimensioning and topological variation of the complex annulus geometry. Parametric methods for an optimised arrangement of the blade stages in a turbomachinery subsystem configuration are shown and integrated into a mathematical model.}, language = {en} } @misc{MischkePohlHoeschleretal., author = {Mischke, Marcel and Pohl, Michael and H{\"o}schler, Klaus and Huppertz, Andr{\ยดe}}, title = {GAS PATH DESIGNER - zeiteffiziente Vorauslegung von Triebwerks-Ringr{\"a}umen und zus{\"a}tzlichen Strukturen}, series = {Conference Paper des Deutscher Luft- und Raumfahrtkongress 2020}, volume = {Deutscher Luft- und Raumfahrtkongress 2020}, journal = {Conference Paper des Deutscher Luft- und Raumfahrtkongress 2020}, publisher = {Deutsche Gesellschaft f{\"u}r Luft- und Raumfahrt - Lilienthal-Oberth e.V.}, address = {Bonn}, doi = {https://doi.org/10.25967/530098}, url = {http://nbn-resolving.de/urn:nbn:de:101:1-2020121112494640076557}, pages = {10}, abstract = {Der Beginn einer jeden Triebwerksentwicklung startet mit der Auslegung des Ringraumes des Prim{\"a}rgasstromes. Hier m{\"u}ssen einige vorl{\"a}ufige aber auch grundlegende Entscheidungen zu Entwurfsparametern wie Eintrittsquerschnitte, Subsysteml{\"a}ngen, axiale Stufenanzahl in Verdichter und Turbine, usw. definiert werden. F{\"u}r die Vorauslegung sollte die Palette an anf{\"a}nglichen Entwurfsparametern so gering wie m{\"o}glich gehalten werden, um die Menge an m{\"o}glichen Ringraumentw{\"u}rfen nicht fr{\"u}hzeitig einzuschr{\"a}nken. Dieses Paper pr{\"a}sentiert das Vorauslegungswerkzeug โ€žGas Path Designer" (GPD), welches in der Lage ist Ringraumentw{\"u}rfe f{\"u}r Turbotriebwerke {\"u}ber zeiteffiziente Berechnungsmethoden in k{\"u}rzester Zeit bereitzustellen. Das Interface bietet eine Auswahl an Einstellungen, um die genannten Variationsm{\"o}glichkeiten zu unterst{\"u}tzen. Der Aufbau ist {\"u}bersichtlich, um im Rahmen grundlegender konzeptorientierter Gespr{\"a}che mit dem Kunden eine schnelle und beidseitig nachvollziehbare Variation und Visualisierung des Konzeptentwurfes zu erm{\"o}glichen. Des Weiteren k{\"o}nnen die erhaltenen Ringraumstrukturen der Triebwerksentw{\"u}rfe als Leitstruktur f{\"u}r CAD-Programme sowie weiterf{\"u}hrende Optimierungsstrategien genutzt werden.}, language = {de} } @misc{XieStarickMosgowetal., author = {Xie, Tianxiao and Starick, Tommy and Mosgow, Anatol and Berg, Heinz Peter and H{\"o}schler, Klaus and Schmidt, Heiko}, title = {Thermofluiddynamic pre-design of a primary surface heat exchanger under the influence of heat radiation using 1D/3D coupled simulation method}, series = {NAFEMS World Congress 2021, online, 25-29. Oktober 2021}, journal = {NAFEMS World Congress 2021, online, 25-29. Oktober 2021}, pages = {25}, abstract = {Within the Framework of the "TurboFuelCell (TFC)" a highly integrated and compact energy conversion system based on Micro Gas Turbine Solid Oxide Fuel Cell (MGT-SOFC) hybrid process is being developed by the team at BTU-Cottbus Senftenberg. This work focuses on the extension of the pre-design process of a primary surface heat exchanger (PSHX), which is a key component for the coupling between MGT and SOFC, using an 1D/3D hybrid simulation method for the understanding of its behaviour under the influence of heat radiation. In a MGT-SOFC hybrid process the high temperature heat exchanger plays an important role in preheating the fresh air to a minimum operation temperature necessary for SOFC. Due to the special location of this PSHX in the TFC, it is constantly exposed to heat radiation from the SOFC module, which requires additional consideration of its influence for better model accuracy. A first design, which is later extended through an 1D Flow network model, based on ๐œ– - ๐‘๐‘‡๐‘ˆ method is presented. A complete 3D-CFD simulation with consideration of heat radiation is initially employed for the whole flow process to examine the first design. However, this approach proves to be highly computationally expensive due to the large dimensional difference between the plenum for cathode exhaust air and the fine channels in the PSHX. To reduce the computational effort, the flow and heat transfer in the PSHX is modelled by 1D elements. The flow in the plenum is simulated by 3D-CFD, which better accounts for convection and thermal radiation. A comparison between 3D-CFD and 1D/3D hybrid model is performed. A significant reduction of simulation time and computing resources can be achieved for well calibrated hybrid model without compromising on accuracy. In the talk, the effect of insulation layer thickness variations on the heat transfer on the plenum side due to heat radiation and their influence on the heat exchanger efficiency are discussed. Consequently, design improvements are realized based on the previous findings. Finally, the 1D/3D hybrid simulation method is evaluated and prepared for the general applications in thermal management of machines based on coupled MGT-SOFC process.}, language = {en} }