The turbulent boundary layer excitation is one of the main sources of aircraft interior noise over a large frequency range while the diffuse sound field excitation is often considered as an approximation for noise analysis and noise control evaluation. In this context local damping effect is investigated through the use of add-on damping patches in comparing insertion losses through a thin plate under both excitations. A thm plate having its critical frequency equal to 4400 Hz and its aerodynamic coincidence frequency equal to 1100 Hz is considered. Numerical results are carried out using an original methodology based on the Minimization of Error on a Sample of Observation Points (MESOP). The transmission loss index is assessed in the frequency range 50 to 7000 Hz. This investigation points out different behaviors: a damping effect is observed only in the critical frequency region under diffuse sound field excitation whereas the transmission loss index is increased over the whole frequency band under turbulent boundary layer excitation. The transmission loss under aerodynamic excitation with varying patch sizes is finally investigated in the context of damping treatments optimization.


    Access

    Access via TIB

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Add-on damping patches efficiency on sound transmission of a thin plate under aerodynamic or acoustic excitation


    Contributors:


    Publication date :

    2009


    Size :

    10 Seiten, 9 Bilder, 1 Tabelle, 18 Quellen



    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English




    Vibration and Acoustic Radiation of Thin-Walled Structures Under Aerodynamic Excitation

    Efimtsov, B. M. / American Institute of Aeronautics and Astronautics | British Library Conference Proceedings | 1993





    Aerodynamic damping of composite UHBR fans under the consideration of acoustic intake reflections

    Gößling, Jan / Seume, Joerg R.. / Flüh, Jan Peter et al. | TIBKAT | 2022

    Free access