An acoustic liner may include a core with a plurality of resonator chambers, a perforated top sheet coupled to the core, and a backskin coupled to the core. A thermoacoustic speaker including nanomaterials may be coupled to at least one of the core, the backskin, and the perforated top sheet. A voltage may be applied to the thermoacoustic speaker. The thermoacoustic carbon nanotube speaker may create a dynamic excitation within a resonator chamber in the core. The dynamic excitation may change the liner acoustic impedance to achieve optimum noise attenuation over a wide range of frequencies or engine operating conditions.


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    Title :

    ACOUSTIC ATTENUATION WITH ADAPTIVE IMPEDANCE


    Contributors:

    Publication date :

    2016-05-26


    Type of media :

    Patent


    Type of material :

    Electronic Resource


    Language :

    English


    Classification :

    IPC:    F01D Strömungsmaschinen [Kraft- und Arbeitsmaschinen oder Kraftmaschinen], z.B. Dampfturbinen , NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES / B64D Ausrüstung für Flugzeuge , EQUIPMENT FOR FITTING IN OR TO AIRCRAFT / G10K Tonerzeugungsvorrichtungen , SOUND-PRODUCING DEVICES / H04R LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS , Lautsprecher, Mikrofone, Schallplatten-Tonabnehmer oder ähnliche akustische, elektromechanische Wandler



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