Sökning: "sound transmission loss"

Visar resultat 1 - 5 av 25 avhandlingar innehållade orden sound transmission loss.

  1. 1. The effects of damping treatment on the sound transmission loss of honeycomb panels

    Författare :Sathish Kumar Ramanathan; Leping Feng; Alexander Peiffer; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Sandwich Structures; Honeycomb Panels; Sound Transmission; Loss Factor; Damping; Sound Radiation; Acoustics; Akustik;

    Sammanfattning : In the industry, all passenger vehicles are treated with damping materials to reduce structure-borne sound. Though these damping materials are effective to attenuate structure-borne sound, they have little or no effect on the air-borne sound transmission. LÄS MER

  3. 2. Sound transmission through aircraft panels

    Författare :Biong Liu; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sound transmission loss; stiffener; stiffening; aircraft panel; cylindrical shell; Vehicle engineering; Farkostteknik;

    Sammanfattning : .... LÄS MER

  4. 3. Transmission loss of vehicle seals

    Författare :Qi Li; Leping Feng; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vehicle seals; reverberation room test; contact analysis; simple model; mass law; FEM analysis; distorted circular duct model; Acoustics; Akustik;

    Sammanfattning : Sound transmission loss of vehicle seals was studied in this thesis. Reverberation room test and semi-anechoic chamber test were respectively studied. LÄS MER

  5. 4. Studies of sound generation and propagation in flow ducts

    Författare :Fabrice Ducret; Mats Åbom; Andy Moorhouse; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; two-port; plane wave; HVAC system; tailpipe; exhaust system; flexible duct; pipe; reflection coefficient; impedance; flow noise; vorticity; damping; scaling laws; impedance; transmission loss; perforated plate; slit; non linearity; Acoustics; Akustik;

    Sammanfattning : This thesis contains three papers investigating problems of interest for noise control in ducts. The first part of this thesis treats the sound propagation in rectangular ducts with flexible walls. Various experimental techniques are performed to measure the internal sound propagation and radiation to the surrounding. LÄS MER

  7. 5. Acoustical Characteristics of Aircraft Panels

    Författare :Bilong Liu; Leping Feng; Jie Pan; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustics; sound transmission loss; stiffener; stiffening; aircraft panel; cylindrical shell; turbulent boundary layer; TBL; noise; sound radiation; Acoustics; Akustik;

    Sammanfattning : A deterministic approach based on a modal expansion and modal receptance method has been developed to evaluate the airborne sound insulation of aircraft panels with stringer and ring frame attachments. Furthermore, this method was extended to predict the noise radiation of stiffening panel subjected to TBL excitation. LÄS MER