@misc{KazulaGrasseltMischkeetal., author = {Kazula, Stefan and Grasselt, David and Mischke, Marcel and H{\"o}schler, Klaus}, title = {Preliminary safety assessment of circular variable nacelle inlet concepts for aero engines in civil aviation}, series = {Safety and Reliability - Safe Societies in a Changing World}, journal = {Safety and Reliability - Safe Societies in a Changing World}, publisher = {Taylor \& Francis Group}, address = {London}, isbn = {978-0-8153-8682-7}, pages = {2459 -- 2467}, abstract = {A safe design process and its application are introduced to a concept study for circular variable aero engine inlets. The paper highlights the tasks of inlets, the compromise in designing them and how using variable inlets could solve this compromise and allow for faster and more efficient commercial aircraft. However, high safety and reliability requirements bring up disadvantages. Tackling these disadvantages, a systems engineering approach is complemented by a safety assessment process, according to Aerospace Recommended Practice ARP 4754A. Safety methods that are applicable during early phases of the product development process are presented and applied to develop feasible variable inlet concepts. Hence, safety requirements, potential failure events and resulting failure modes are systematically identified, assessed and mitigated. The mitigation of a failure condition by the means of redundancy within the adjustment control system is presented.}, language = {en} } @inproceedings{MischkeKazulaHoeschler, author = {Mischke, Marcel and Kazula, Stefan and H{\"o}schler, Klaus}, title = {A Comparative Concept Study and Evaluation for New Broadband Noise Absorbing Acoustic Liner Concepts for Civil Aviation}, series = {Proceedings of Global Power and Propulsion Society, Technical Conference 2019, Zurich}, booktitle = {Proceedings of Global Power and Propulsion Society, Technical Conference 2019, Zurich}, pages = {1 -- 9}, abstract = {This paper presents an approach to product rating and evaluation of different product solutions for broadband attenuation acoustic liner concepts for aerospace application. In the process, corresponding requirements have been defined for the considered system and evaluation criteria have been derived. Three "Main Evaluation Categories" (Acoustics, System Safety and Integration, Structure and Material) have been introduced to not falsify the assessment results by subject-specific exclusion criteria. A ranked space method has been selected for weighting the evaluation criteria to ensure an objective and knowledge-based rating. The rating has been carried out by a weighted point rating. Concise operational requirements and previously not considered system functions have been identified and linked to the rating and evaluation process. Building on this, further steps for the optimisation and development of the acoustic liner concepts have been presented and explained.}, language = {en} } @misc{KazulaMischkeKoenigetal., author = {Kazula, Stefan and Mischke, Marcel and K{\"o}nig, Paul and H{\"o}schler, Klaus}, title = {Evaluation of Variable Pitot Inlet Concepts for Transonic and Supersonic Civil Aviation}, series = {MATEC Web of Conferences : Proceedings of the 9th EASN International Conference on Innovation in Aviation \& Space}, volume = {304}, journal = {MATEC Web of Conferences : Proceedings of the 9th EASN International Conference on Innovation in Aviation \& Space}, issn = {2261-236X}, doi = {10.1051/matecconf/201930402016}, pages = {8}, abstract = {This paper describes the selection of the ideal variable inlet concept group by utilising results of aerodynamic investigations, system safety analyses and integration studies. 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. By means of this evaluation, the concept group that adjusts the inlet geometry by rigid segment repositioning is identified as most suitable concept group. 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{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{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} }