Dokument-ID Dokumenttyp Verfasser/Autoren Herausgeber Haupttitel Abstract Auflage Verlagsort Verlag Erscheinungsjahr Seitenzahl Schriftenreihe Titel Schriftenreihe Bandzahl ISBN Quelle der Hochschulschrift Konferenzname Bemerkung Quelle:Titel Quelle:Jahrgang Quelle:Heftnummer Quelle:Erste Seite Quelle:Letzte Seite URN DOI Zugriffsart Link Abteilungen OPUS4-10548 Konferenzveröffentlichung Hille, Sebastian, ; Stumpf, Eike, ; Mayntz, Joscha, mayntz@fh-aachen.de; Dahmann, Peter, dahmann@fh-aachen.de Prediction of sound exposure caused by a landing motor glider with recuperating propellers This paper presents an approach to predicting the sound exposure on the ground caused by a landing aircraft with recuperating propellers. The noise source along the trajectory of a flight specified for a steeper approach is simulated based on measurements of sound power levels and additional parameters of a single propeller placed in a wind tunnel. To validate the measured data/measurement results, these simulations are also supported by overflight measurements of a test aircraft. It is shown that the simple source models of propellers do not provide fully satisfactory results since the sound levels are estimated too low. Nevertheless, with a further reference comparison, margins for an acceptable increase in the sound power level of the aircraft on its now steeper approach path could be estimated. Thus, in this case, a +7 dB increase in SWL would not increase the SEL compared to the conventional approach within only 2 km ahead of the airfield. AIAA 2023 AIAA SCITECH 2023 Forum AIAA SCITECH 2023 Forum, 23-27 January 2023, National Harbor, MD & Online 10.2514/6.2023-0211 bezahl https://doi.org/10.2514/6.2023-0211 Fachbereich Luft- und Raumfahrttechnik OPUS4-10981 Wissenschaftlicher Artikel Hammer, Thorben, ; Quitter, Julius, quitter@fh-aachen.de; Mayntz, Joscha, mayntz@fh-aachen.de; Bauschat, J.-Michael, bauschat@fh-aachen.de; Dahmann, Peter, dahmann@fh-aachen.de; Götten, Falk, goetten@fh-aachen.de; Hille, S., ; Stumpf, E., Free fall drag estimation of small-scale multirotor unmanned aircraft systems using computational fluid dynamics and wind tunnel experiments New European Union (EU) regulations for UAS operations require an operational risk analysis, which includes an estimation of the potential danger of the UAS crashing. A key parameter for the potential ground risk is the kinetic impact energy of the UAS. The kinetic energy depends on the impact velocity of the UAS and, therefore, on the aerodynamic drag and the weight during free fall. Hence, estimating the impact energy of a UAS requires an accurate drag estimation of the UAS in that state. The paper at hand presents the aerodynamic drag estimation of small-scale multirotor UAS. Multirotor UAS of various sizes and configurations were analysed with a fully unsteady Reynolds-averaged Navier-Stokes approach. These simulations included different velocities and various fuselage pitch angles of the UAS. The results were compared against force measurements performed in a subsonic wind tunnel and provided good consistency. Furthermore, the influence of the UAS`s fuselage pitch angle as well as the influence of fixed and free spinning propellers on the aerodynamic drag was analysed. Free spinning propellers may increase the drag by up to 110%, depending on the fuselage pitch angle. Increasing the fuselage pitch angle of the UAS lowers the drag by 40% up to 85%, depending on the UAS. The data presented in this paper allow for increased accuracy of ground risk assessments. Wien Springer 2023 14 Seiten CEAS Aeronautical Journal Corresponding author: Thorben Hammer 10.1007/s13272-023-00702-w weltweit https://doi.org/10.1007/s13272-023-00702-w Fachbereich Luft- und Raumfahrttechnik OPUS4-9249 Konferenzveröffentlichung Finger, Felix, f.finger@fh-aachen.de; Khalsa, R., ; Kreyer, Jörg, kreyer@fh-aachen.de; Mayntz, Joscha, mayntz@fh-aachen.de; Braun, Carsten, c.braun@fh-aachen.de; Dahmann, Peter, dahmann@fh-aachen.de; Esch, Thomas, esch@fh-aachen.de; Kemper, Hans, h.kemper@fh-aachen.de; Schmitz, O., ; Bragard, Michael, bragard@fh-aachen.de An approach to propulsion system modelling for the conceptual design of hybrid-electric general aviation aircraft In this paper, an approach to propulsion system modelling for hybrid-electric general aviation aircraft is presented. Because the focus is on general aviation aircraft, only combinations of electric motors and reciprocating combustion engines are explored. Gas turbine hybrids will not be considered. The level of the component's models is appropriate for the conceptual design stage. They are simple and adaptable, so that a wide range of designs with morphologically different propulsive system architectures can be quickly compared. Modelling strategies for both mass and efficiency of each part of the propulsion system (engine, motor, battery and propeller) will be presented. 2019 15 Seiten Deutscher Luft- und Raumfahrtkongress 2019, 30.9.-2.10.2019, Darmstadt Fachbereich Elektrotechnik und Informationstechnik