Who should attend:

New Actran users. Experience with Actran is not required. Acoustics background is preferable.

Overview:

This session addresses all kind of cabin noise issues: structural vibrations, external sources like air intake and exhaust, noise due to turbulences caused by a side mirror or a front pillar and wall transparency. The fluid structure coupling as well as the use of trim elements within Actran, among others, will be described.

Topics covered:

  • Introduction to the acoustic and the vibro-acoustic simulations, including viscothermal effects and porous materials
  • Modeling panel and window components:
    - Multilayer panel: solid shell and solid elements for materials like foam, metal and glass
    - Composite panel: shell elements, fiber directions and homogenization technique
  • Acoustic radiation:
    - For planar shapes: Rayleigh surface
    - For complex shapes: incompatible mesh and infinite elements
  • Excitations:
    - Plane waves, monopole, mechanical forces, distributed pressure
    - Random excitations: diffuse field, turbulent boundary layers, rain-on-the-roof
    - Vibrations induced by structural loading computed with an external software
    - Aero-acoustic sources: Möhring and Lightill analogies
  • Post processing: noise at driver’s ears, acoustic transmission loss, energy dissipated by porous and structural elements