How TMM/FTMM simulations help you understand the vibro-acoustic response of multi-layer systems

  • 94 views
Uploaded on

Ever demanding NVH solutions require a fine understanding of the treatment functioning. This talk will show how TMM/FTMM solution help to get further insight into the energy dissipation mechanisms in …

Ever demanding NVH solutions require a fine understanding of the treatment functioning. This talk will show how TMM/FTMM solution help to get further insight into the energy dissipation mechanisms in various configurations of systems and sound excitation. This type of tool may be used either at the writing of the specification, the design stage or to control the expected noise performance. Based on the expression of the field continuity at each material interface in a multi-layer trim, this approach is computationally efficient, allowing for large parametrical studies. The tool presented here, named AlphaCell, associates an efficient computational core to an intuitive interface. It allows the prediction of the vibro-acoustic response of multi-layer systems to various sound excitations : plane wave at normal incidence (i.e. impedance tube conditions), diffuse sound field, impact sound, rain on the roof and turbulent boundary layer excitation. The discussed examples will comprise vibrating perforated plate based systems, multi-layer trims including visco-elastic layers, studded walls, underlay solutions and glazing subjected to turbulent boundary layer excitation. It will be shown that integrating this type of tool in the design chain allows quicker and more robust NVH product developments.

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
    Be the first to like this
No Downloads

Views

Total Views
94
On Slideshare
0
From Embeds
0
Number of Embeds
4

Actions

Shares
Downloads
3
Comments
0
Likes
0

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. How TMM/FTMM simulations help you understand the vibro-acoustic response of multi-layer systems François-Xavier Bécot Fabien Chevillotte, Luc Jaouen Booth 11 Altair Technology Conference Munich, Germany – 26.Jun.2014 www.matelys.com
  • 2. Acknowledgements to my colleagues Fabien Chevillotte and Luc Jaouen . . . www.matelys.com
  • 3. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions A few words about www.matelys.com
  • 4. www.matelys.com
  • 5. www.matelys.com
  • 6. Matelys is an independent research laboratory dedicated to the study of porous materials in acoustics, thermics, elastics and flow Characterisation Prescription R&D services Software Digest Accredited French Research Ministry (CIR) since 2007 and awarded by peers www.matelys.com
  • 7. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Acoustic description of porous materials Industrial applications : automotive Industrial applications : aeronautics Industrial applications : multi-physics Conclusions F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 8. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Acoustic description of porous materials • TMM : Transfer Matrix Method • principles of modeling Industrial applications : automotive Industrial applications : aeronautics Industrial applications : multi-physics Conclusions F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 9. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions FEM compared to TMM Cell F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 10. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Acoustic description of porous materials • TMM : Transfer Matrix Method • principles of modeling Industrial applications : automotive Industrial applications : aeronautics Industrial applications : multi-physics Conclusions F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 11. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 12. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Air saturated pores Solid frames Emmental Melaminefoam F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 13. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Poro-visco-elastic medium ⇔ Two phases’ medium F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 14. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Poro-visco-elastic medium ⇔ Two phases’ medium F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 15. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Two phases’ medium ⇔ homogenisation F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 16. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Two phases’ medium ⇔ homogenisation λ charac. dim◦ F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 17. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Homogenisation ⇔ semi-phenomenological models λ charac. dim◦ F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 18. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Homogenisation ⇔ semi-phenomenological models λ charac. dim◦ Three types of dissipations in the fluid phase • viscous flow • thermal exchanges with skeleton F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 19. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Homogenisation ⇔ semi-phenomenological models λ charac. dim◦ Three types of dissipations in the fluid phase • viscous flow • thermal exchanges with skeleton in the solid phase • structural (skeleton deformation) F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 20. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Rigid & motionless behaviour Road pavement Limp behavior: Youngʹs modulus close to 0 Rigid body behavior: Low mass density to stiffness ratio Cotton candy Flower foam Visco-Elastic skeleton Soft-touch mattress Biot model Acoustical and elastical parameters required. Acoustical parameters required only. Equivalent fluid model 2 phases coupled 2 phases NOT coupled F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 21. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Acoustic description of porous materials Industrial applications : automotive • multi-scale optimisation study Industrial applications : aeronautics Industrial applications : multi-physics Conclusions F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 22. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Sound insulation performance of a multi-layer sound package ⇒ coupling Micro-Macro & Multi-layer modelling ScalingCell Cell F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 23. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Acoustic description of porous materials Industrial applications : automotive Industrial applications : aeronautics • sound paths in studded partition Industrial applications : multi-physics Conclusions F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 24. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Identifying the sound paths in studded partitions 10 2 10 3 10 4 Frequency64Hz) Diffuse6field6sound6transmission6loss64dB) Solid6borne GW6airborne GW6total6:6364−5;−12) MEL6airborne MEL6total6:6354−5;−12) 20 dB ⇒ little impact of filling material F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 25. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Acoustic description of porous materials Industrial applications : automotive Industrial applications : aeronautics Industrial applications : multi-physics • material scale • component scale Conclusions F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 26. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Cubic centered cell with pore closing membranes fluid phase solid phase without membranes solid phase with membranes F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 27. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Tuning the size of the “windows” “natural” opening “forced” opening F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 28. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Influence of the pore window size Thermal conductivity (% of max value) M1 calc. M2 calc. M3 calc. M4 calc. M4 > M3 > M2 > M1 Ri Ri Ri Ri Rw6(micrometres) Thermal6conductivity6(%6max6value) 100 50 0 75 25 0 100 200 300 400 500 600 F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 29. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Influence of the pore window size Sound absorption coefficient in diffuse field (ISO 354) 0 1000 2000 3000 4000 5000 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 MATELYS−AcV/Jul13 SoundRabsorptionRcoef.RdiffuseRfieldR(ISOR354) FrequencyR(Hz) 56RRRRpR=R0.45R(H) 106RRpR=R0.30R(H) 206RRpR=R0.25R(H) 306RRpR=R0.20R(H) 406RRpR=R0.20R(H) 506RRpR=R0.15R(H) 606RRpR=R0.15R F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 30. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Acoustic description of porous materials Industrial applications : automotive Industrial applications : aeronautics Industrial applications : multi-physics • material scale • component scale Conclusions F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 31. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Acousto-thermal behaviour Vs. volumic mass 80% 85% 90% 95% 100% 80% 85% 90% 95% 100% Volumic mass (kg/m3) Rw+C (% max value)Thermal resistance (% max value) F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 32. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Acousto-thermal behaviour Vs. convection in air gaps 70% 75% 80% 85% 90% 95% 100% 70% 75% 80% 85% 90% 95% 100% Configuration of air gaps (mm) Rw+C (% max value)Thermal resistance (% max value) F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 33. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Acoustic description of porous materials Industrial applications : automotive Industrial applications : aeronautics Industrial applications : multi-physics Conclusions F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 34. Matelys TMM & Porous Materials Automotive Aeronautics Multi-physics Conclusions Future materials • heterogeneous materials • graded materials • hybrid passive / active materials / energy harvester Stakes • morphing technologies • 3D printing / structured materials • multi-physics development • multi-functional materials • manufacturing capacities • technological know-how F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014
  • 35. Thank you for your attention ! SAPEM 2014 in KTH (Stockholm-Sweden) 16-17-18 December 2014 http://sapem2014.matelys.com/ Acoustical Porous Material Recipes TMM/FTMM Micro-Macro model Porous charac. Cell ScalingCell CellCellRoK F.-X. Bécot – www.matelys.com EATC – 26.Jun.2014