Simulation of Acoustic Materials
Acoustical materials are used in many noise control applications for reducing airborne sound and to enhance the transmission loss of the barrier. Acoustical performance of the porous materials can be characterized by sound absorption and sound transmission loss. The measurement of these parameters takes lot of time and money. So it is necessary to predict acoustic properties of porous materials by simulation. Acoustic porous materials are modeled according to their nature i.e. rigid, limp and elastic as per literature. To predict acoustic performance, five intrinsic parameters viz., porosity, airflow resistivity, tortuosity, VCL and TCL are required.
Simulation of Polyurethane Foam
Simulation of Glass Wool
For fibrous materials like Glass wool, Rockwool, Polyester fibers, it is possible to predict acoustic behavior from only Airflow resistivity of the material. The figure below shows the simulation and experimental validation for Glass wool
Effect of Thickness on Sound Absorption Coefficient