This paper addresses acoustic scattering of rotorcraft noise in the time domain. A time-domain equivalent source method is used since it is considered to be a computationally efficient method to solve acoustic scattering. In addition, the time-domain method provides a solution for all frequencies of interest in a single computation and is able to predict the acoustic scattering of aperiodic signals. The prediction is validated against exact solutions for a monopole source. The numerical method is then used to predict acoustic scattering of noise from a BO105 tail rotor by a representative fuselage. Complex directivity patterns are seen in the near field, and a large scattering effect is observed in the far field to the side of the fuselage. The time-domain code results of sound pressure level are validated against the results obtained by a frequency-domain analysis. Finally, acoustic scattering for an impulsive noise source is investigated to simulate main rotor blade-vortex interaction noise. The scattered pressure has a comparable amplitude as that of the incident pressure so that the total pressure is dramatically changed compared to the incident pressure. For the impulsive noise, a large computational time saving is achieved compared to the frequency-domain approach, in which the computation must be repeated for each frequency.


    Zugriff

    Zugriff über TIB

    Verfügbarkeit in meiner Bibliothek prüfen

    Bestellung bei Subito €


    Exportieren, teilen und zitieren



    Titel :

    Time-domain approach for acoustic scattering of rotorcraft noise


    Weitere Titelangaben:

    Zeitbereichanalyse der Schallemission eines Drehflüglers


    Beteiligte:

    Erschienen in:

    Journal of the American Helicopter Society ; 57 , 4 ; 042001/1-042001/12


    Erscheinungsdatum :

    2012


    Format / Umfang :

    12 Seiten, 14 Bilder, 1 Tabelle, 22 Quellen




    Medientyp :

    Aufsatz (Zeitschrift)


    Format :

    Print


    Sprache :

    Englisch




    Time-Domain Approach for Acoustic Scattering of Rotorcraft Noise

    Lee, S. / Brentner, K. / Morris, P. et al. | British Library Conference Proceedings | 2009



    Acoustic Scattering of Rotorcraft Noise

    Lee, S. / Erwin, J. / Brentner, K. et al. | British Library Conference Proceedings | 2008



    A method to predict acoustic scattering of rotorcraft noise

    Lee, Seongkyu / Erwin, James P. / Brentner, Kenneth S. | Tema Archiv | 2009