APMR : Acoustical Porous Material Recipes

The aim of this site is to gather information and feedbacks about published or unpublished works in the field of acoustical porous material: models for the propagation of sound, parameter definitions and characterization techniques, standards...

 

Interactive slides of Luc Jaouen's talk at the International Workshop on Building Acoustics and Noise Control (IWBA), August 22-23, 2022 (CSIR-National Physical Laboratory, New Delhi, India)..

Content

The content of APMR is growing day after day.
Below is a table of contents of the subjects discussed or planned to be discussed and a search engine.

 (: APMR only)

Propagation models

• Motionless skeleton (equivalent fluid)
• Delany-Bazley
• Delany-Bazley-Miki
• Johnson-Champoux-Allard
• Johnson-Champoux-Allard-Lafarge
• Johnson-Champoux-Allard-Pride-Lafarge
• Wilson
• Uniform pressure (equivalent solid)
• Diphasic (Biot's theory)
• Linking micro-structure to macro-properties

Parameters of models

• Static air flow resistivity (& static permeability)
• Open porosity
• High frequency limit of the dynamic tortuosity
• Viscous characteristic length
• Thermal characteristic length
• Static thermal permeability

Characterization of parameters

• Static air flow resistivity (& permeability)
• Open porosity
• High frequency limit of the dynamic tortuosity
• Viscous characteristic length
• Thermal characteristic length
• Static thermal permeability
• Conditions on parameters

Basics of Acoustics

• Compressional wave
• Propagative vs. standing waves
• Wave number
• Wave dispersion
• Length corrections
• Darcy's law
• Viscous boundary layer
• Helmholtz resonator
• Transmission Loss of a single partition
• The coincidence frequency

Basics of Mechanics

• Single degree of freedom (SDOF) systems
• Solution to undamped 1D harmonic oscillator
• Beam bending (compute eigenfrequencies)
• Comparison of damping models
• Snell-Descartes to variational principles
• Variational methods
• Flow around a disk
• Limits of plate theories
     (Added March 30, 2022)
• Condensed models for multilayer structures
     (Added March 30, 2022)

Basics of Materials

• Material classes
• A note about "meta-materials"
• A note about fractional derivatives
     used in some visco-elastic models

Standards

• A list of standards for acoustical materials
• Octave and third-octave bands from ISO 3
• Sound Absorption Average from ASTM C423

Upcoming events

Below are conferences or events for which one or more sessions on acoustical porous materials are organized.

NOVEM 2023 (NOise and Vibration Emerging Methods)

Jan. 10-12, 2023 - Auckland (New Zealand)

Abstract submission deadline: June 30, 2022 for peer-reviewed submission
(July 31, 2022 otherwise)
Early bird registration deadline: Nov. 1, 2022

Forum Acusticum 2023

Sept. 11-15, 2023 - Turino (Italy)

Abstract submission deadline: January 31, 2023
Early bird registration: not known yet

SAPEM 2023 (Symposium on the Acoustics of Poro-Elastic Materials)

dates to be announced later