Simulate Acoustic Absorption Parameters

AcoustoDict

The AcoustoDict module can be considered a digital impedance tube, as it allows the simulation of the acoustic properties of porous microstructures.

Based on a digital model or CT scan, a set of parameters describing the acoustic behavior of the material are computed. These parameters can be used as input to the empirical Delany-Bazley model. Using this model, AcoustoDict predicts the frequency-dependent acoustic absorption curve.

Examples of Applications

  • Research of materials for noise reduction for the automotive industry (e.g. car roof lining) 
  • Research of sound attenuation in architectural materials

Examples of Applications

AcoustoDict Features

Simulation component

The simulation component performs a flow simulation and predicts the input parameters for the Delany-Bazley model from the results. 

Material database

With the database component, absorption curves obtained from these simulations or from direct measurements are stored for later use. Multiple absorption curves at different degrees of compression can be stored and compared for each material, for example, for nonwovens that are often compressed to a given thickness as part of acoustic material fabrication process. The absorption curves for other degrees of compression can then be predicted interactively from the given data.

Match function

The database Match function automatically finds the material that most closely matches a desired absorption curve among the materials within the database. The compression of existing materials to new thicknesses is also taken into account automatically.

Stack function

The database Stack function predicts the acoustic absorption of a sandwich configuration of up to four layers of different materials, including air gaps. The arrangement and thickness of each layer can be changed individually and the absorption curve for the whole stack is updated interactively.

Additional modules needed?

  • The GeoDict Base package is needed for basic functionality.
  • ImportGeo-Vol: for the import and segmentation of the µCT images and the generation of the 3D structural models 
  • FlowDict: required for the prediction of acoustic absorption based on a digital structural model. However, if only the functionality of the material database is needed, for example because the database is created based on direct measurement results, FlowDict can be omitted.