Sökning: "vibro-acoustic"

Visar resultat 1 - 5 av 7 avhandlingar innehållade ordet vibro-acoustic.

  1. 1. Hierarchical finite element modelling of Biot's equations for vibro-acoustic modelling of layered poroelastic media

    Författare :Nils-Erik Hörlin; Peter Göransson; Frank Ihlenburg; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering physics; finite element; hierarchical; Biot; porous material; vibro-acoustic; Teknisk fysik; Engineering physics; Teknisk fysik;

    Sammanfattning : This thesis concerns three-dimensional finite element modelling of Biot's equations for elasto-acoustic modelling of wave propagation in layered media including porous elastic materials. The concept of hierarchical (p-version) finite elements are combined with various weak forms of Biot's equations. LÄS MER

  3. 2. Vibro-acoustic modelling of anisotropic poroelastic materials : characterisation of the anisotropic properties

    Författare :Christophe Van der Kelen; Peter Göransson; Wim Desmet; Kirill Horoshenkov; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : The present-day challenges in the transport industry, steered by the increasing environmental awareness, necessitate manufacturers to take measures to reduce emissions related to the movements of goods and humans. In particular, the measures aiming at a reduced mass or higher load capacity to increase fuel efficiency,  generally deteriorate the noise and vibration insulation properties of their products. LÄS MER

  4. 3. A Vibro-Acoustic Study of Vehicle Suspension Systems : Experimental and Mathematical Component Approaches

    Författare :Eskil Lindberg; Nils-Erik Hörlin; Peter Göransson; Henry Rice; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustics; Vehicle suspension; Disc brake; Wheel rim Roughness noise; Interior tyre-road noise Component mode synthesis; Undeformed coupling interface;

    Sammanfattning : The objective of the present work is to study the vehicle suspension as a vibro-acoustic system of high complexity, consisting of many sub-systems with fundamentally different acoustical properties. In a parallel numerical and experimental modelling effort, important contributions to the understanding of its behaviour have been achieved. LÄS MER

  5. 4. Hybrid and Dynamic Substructuring Methods for Energy Flow Analysis

    Författare :Anders Wilson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fractional derivatives; structural modeling; mid-frequency; finite element method FEM; vibro-acoustics; statistical energy analysis SEA; dynamic substructuring; hybrid analysis; viscoelasticity;

    Sammanfattning : Modeling techniques and solution tools to analyze the dynamic and vibro-acoustic behavior of complex built-up structures are matters of increasing interest, especially for thin walled structures as in transportation vehicles, such as automobiles, trucks, trains and aircraft. In structures like these, the reduction of cost, weight, sound and vibration levels are primary issues for research and development. LÄS MER

  7. 5. Vehicle Disc Brake Roughness Noise : Experimental Study of the Interior Noise andVibro-Acoustic Modelling of Suspension Systems

    Författare :Eskil Lindberg; Nils-Erik Hörlin; Peter Göransson; Wolfgang Kropp; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; acoustics; disc brake; surface topography; wire brush noise; roughness noise; component mode synthesis; vehicle suspension;

    Sammanfattning : Prediction of vehicle disc brake roughness noise is a non-trivial challenge. In fact, neither the source mechanisms, nor the transfer paths are so far well understood. LÄS MER