Sökning: "Wim Desmet"

Hittade 4 avhandlingar innehållade orden Wim Desmet.

1. 1. Predicting and optimising acoustical and vibrational performance of open porous foams

   Författare :Eleonora Lind; Peter Göransson; Wim Desmet; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; porous material; foam; Biot; optimisation; tortuosity; permeability; Acoustics; Akustik;

   Sammanfattning : This thesis concerns the modelling of acoustical and vibrational properties of open cell porous foams in multi-layered structures, especially multi-layered panels. The object is to enable optimisation of the microscopic geometry of the foam with respect to macroscopic quantities such as sound pressure level, surface velocity, total mass or cost. LÄS MER

3. 2. Discrete element simulation of elasto-plastic shock waves in high-velocity compaction

   Författare :Muhammad Shoaib; Leaf Kari; Bruska Azhdar; Wim Desmet; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; High-velocity compaction; Discrete element method; Plastic deformaiton; dynaimic loading; elasto-plastic shock wave; Friction; Adhesion; Physics; Fysik; Järnvägsgruppen - Ljud och vibrationer; Järnvägsgruppen - Ljud och vibrationer;

   Sammanfattning : Elasto-plastic shock waves in high-velocity compaction of spherical metal particles are the focus of this thesis which consists of four papers (A-D). The compaction process is modeled by a discrete element method while using elastic and plastic loading, elastic unloading and adhesion at contacts. LÄS MER

4. 3. The influence of tyre air cavities on vehicle acoustics

   Författare :Èric Torra i Fernàndez; Anders Nilsson; Wim Desmet; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; acoustics; tyre-road noise; tyre; air cavity resonances; interior noise; aluminium foams; Acoustics; Akustik;

   Sammanfattning : The tonal character of the low frequency internal noise in cars is often due to energy transmission through the tyre at the first few eigenfrequencies of the air cavity of the tyre. The first acoustic mode in the air cavity of a typical stationary car tyre is approximately 224 Hz. LÄS MER

5. 4. 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