@inproceedings{GrasseltHoeschlerSain, author = {Grasselt, David and H{\"o}schler, Klaus and Sain, Chetan Kumar}, title = {Fluid-Structure Interaction With a Fully Integrated Multiphysics Environment}, series = {Proceedings of the ASME Fluids Engineering Division Summer Meeting - 2017, presented at the ASME 2017 Fluids Engineering Division Summer Meeting, July 30-August 3, 2017, Waikoloa, Hawaii, USA, Volume 1B}, booktitle = {Proceedings of the ASME Fluids Engineering Division Summer Meeting - 2017, presented at the ASME 2017 Fluids Engineering Division Summer Meeting, July 30-August 3, 2017, Waikoloa, Hawaii, USA, Volume 1B}, publisher = {ASME}, address = {New York, NY}, isbn = {978-0-7918-5805-9}, doi = {10.1115/FEDSM2017-69078}, pages = {8}, abstract = {The paper is focusing on Fluid-Structure Interaction (FSI) process modelling to look for the aero-elastic equilibrium with commercial software packages. The center of intention is to prove whether Ansys Workbench is capable to handle industrial size FSI applications on the one side and to identify possible excitation regions in the example case on the other. The three steps taken to come to a thermal-enhanced bidirectional fluid-structure approach within a fully integrated (monolithic) multiphysics environment are explained: aerodynamic assessment, thermo-structure mechanical setup and unidirectional coupling, as well as bidirectional coupling. Each subchapter describes the specific challenges, how they are solved and which results can be obtained or expected. The paper is focusing on the setup of a bidirectional process chain and does not set the thematic priority on detailed modelling and its results.}, language = {en} } @misc{GrasseltHoeschlerKazula, author = {Grasselt, David and H{\"o}schler, Klaus and Kazula, Stefan}, title = {A Design Approach for a Coupled Actuator System for Variable Nozzles and Thrust Reverser of Aero Engines}, series = {Proceedings of ISABE 2017, ISABE-2017-21450, Manchester, September 3.-8., 2017}, journal = {Proceedings of ISABE 2017, ISABE-2017-21450, Manchester, September 3.-8., 2017}, publisher = {ISABE}, pages = {11}, language = {en} } @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} } @misc{KazulaWoellnerGrasseltetal., author = {Kazula, Stefan and W{\"o}llner, Mark and Grasselt, David and H{\"o}schler, Klaus}, title = {Parametric Design Study on Aerodynamic Characteristics of Variable Pitot Inlets 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/201930402017}, pages = {8}, abstract = {This paper reveals the influence of selected geometric parameters on the aerodynamic performance of circular variable aero engine inlets in transonic and supersonic civil aviation. The trade-off in inlet design and aerodynamic evaluation parameters are 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. 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.}, language = {en} } @inproceedings{KazulaGrasseltHoeschler, author = {Kazula, Stefan and Grasselt, David and H{\"o}schler, Klaus}, title = {Common cause analysis of circular variable nacelle inlet concepts for aero engines in civil aviation}, series = {Proceedings IRF2018: 6th International Conference Integrity-Reliability-Failure, Lisbon/Portugal, 22-26 July 2018}, booktitle = {Proceedings IRF2018: 6th International Conference Integrity-Reliability-Failure, Lisbon/Portugal, 22-26 July 2018}, editor = {Silva Gomes, J. F. and Meguid, Shaker A.}, publisher = {INEGI/FEUP}, address = {Lisbon}, isbn = {978-989-20-8313-1}, pages = {759 -- 770}, abstract = {This paper presents the application of a safe design process within a concept study for variable aero engine inlets. The safety assessment method Common Cause Analysis (CCA), consisting of a Zonal Safety Analysis (ZSA), a Particular Risk Analysis (PRA) and a Common Mode Analysis (CMA), is performed on variable inlet concepts. By the means of the CCA individual failure modes and external events, which can lead to failure conditions, are identified. Potential design adaptations to mitigate these failure conditions are presented.}, language = {en} } @inproceedings{GrasseltHoeschler, author = {Grasselt, David and H{\"o}schler, Klaus}, title = {Safety Assessment of Aero Engine Thrust Reverser Actuation Systems : ISABE-2015-20260}, series = {22nd International Symposium on Air Breathing Engines (ISABE-2015-20260), 25.-30. Oktober 2015, Phoenix (AZ, USA)}, booktitle = {22nd International Symposium on Air Breathing Engines (ISABE-2015-20260), 25.-30. Oktober 2015, Phoenix (AZ, USA)}, publisher = {ISABE}, pages = {7}, language = {en} } @inproceedings{GrasseltHoeschler, author = {Grasselt, David and H{\"o}schler, Klaus}, title = {Vergleich von FSI Methoden kommerzieller integrativer Programme gegen{\"u}ber inkonsistenten L{\"o}sungen am Beispiel eines Schubumkehrers im Flug-Triebwerk}, series = {Deutscher Luft- und Raumfahrtkongress 2015, 22. -24. September 2015, Rostock}, booktitle = {Deutscher Luft- und Raumfahrtkongress 2015, 22. -24. September 2015, Rostock}, publisher = {Deutsche Gesellschaft f{\"u}r Luft- und Raumfahrt - Lilienthal-Oberth e.V.}, address = {Bonn}, url = {http://nbn-resolving.de/urn:nbn:de:101:1-201512113094}, pages = {7}, language = {de} } @inproceedings{GrasseltHoeschlerKonstantinidis, author = {Grasselt, David and H{\"o}schler, Klaus and Konstantinidis, Aris}, title = {Fluid Structure Interaction with Inconsistent Software Platforms}, series = {ECCOMAS, Barcelona 2014}, booktitle = {ECCOMAS, Barcelona 2014}, abstract = {The FSI problem class describes the mutual dependence of the multiphysical interaction between aerodynamic forces and structural mechanic deformation. The FSI effects become more significant and influences partially safety analysis when the dependence between the influence and response becomes stronger, e.g. the fluttering of aero-engine blades or the pumping of blood by the ventricles of the human heart. [1] The modelling of fluid dynamic problems requires solutions different from those, which are relevant for structure mechanical issues. The coupling of modern numerical methods and tools enables the analysis of mutual dependencies. Although software companies develop more and more integrated solutions, inconsistent application of software solutions (SW) play an important role. Furthermore, automation of interface processing, finite-element analysis (FEA) and computational fluid dynamic (CFD) solution processes can lead to significant exploitation potential for example for design-optimisation applications, design evaluation with target solver-, Monte Carlo-, six sigma-, Taguchi- and stochastic design improval methods or is capable to just accelerate the design process. This requires the strict separation of method code and application dependent information. The paper describes a coupling approach, in the case of obligatory use of inconsistent SW for the separate, mutual depending challenges of a FSI problem description, especially for strong displacement applications. The first step of a FSI process chain is the solution of a fluid dynamic problem followed by a coupled FE Analysis. The start of the FE solution process can be divided into three steps: • the pre-processing and generation of a finite-element-model input file, • the manipulation with an external code, including the required time and data management, • the execution of the FEM solver with the manipulated input file. Typical finite-element-codes generate an input file and process this file with a SW specific interface. A self-coded Java programme uses this interface strategy to manipulate the structural solvers' input before executing the solver. The outcome of the FE solution can be divided into two types of information. The most obvious is numerical output in form of stress or displacement. Additionally FSI process relevant information is required to allow the coupling of FEA to the CFD analysis: boundary conditions, like surface pressure or heat transfer coefficients distributions provoked deformation of the component. A key method to allow importing deformed surfaces to form the 2nd coupling way is the description of surfaces using non-uniform rational B-splines.}, 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{KazulaWoellnerGrasseltetal., author = {Kazula, Stefan and W{\"o}llner, Mark and Grasselt, David and H{\"o}schler, Klaus}, title = {Parametric design and aerodynamic analysis of circular variable aero engine inlets for transonic and supersonic civil aviation}, series = {Proceedings of the 24th ISABE Conference : ISABE 2019-24018}, journal = {Proceedings of the 24th ISABE Conference : ISABE 2019-24018}, address = {Canberra}, pages = {39}, abstract = {This paper focusses on the challenge of determining the ideal inlet geometries within a concept study for variable pitot aero engine inlets in transonic and supersonic civil aviation. The trade-off in inlet design and the geometric parameters of inlets for different Mach numbers are introduced. The utilised process of the parametric design study and its implementation are presented. The dependencies of inlet drag and occurrence of flow separation from geometric parameters are examined. The ideal inlet geometries are identified to determine the potential aerodynamic benefit of using variable pitot inlets. The comparison of the identified geometries with the reference reveals a significant drag reduction at the investigated flight speeds of Mach 0.95, 1.3 and 1.6. While the drag reduction potentially leads to decreased fuel consumption and increased flight range, the application of variable inlet systems entails additional weight and complexity. By means of a simplified Breguet range equation, the benefit of using variable pitot inlets has been determined. For an additional weight of 500 kg per variable inlet, the range benefit nearly disappears for subsonic applications up to Mach 0.95, while a range benefit of over 20\% remains for supersonic applications at Mach 1.6.}, language = {en} }