Macroscopic Approach to Predict Acoustical Properties
Macroscopic approach to predict acoustical properties of materials
Acoustic materials is reffered sound absorbing materials or sound barriers to reduce noise in space such as buildings or automobile. So, predicting the sound absorption and insulation performance of a material has an important effect on predicting noise inside a vehicle or building when the material is applied. Sound absorbing material absorbs sound by dissipating acoustic energy entering the material into kinetic energy of the material and thermal energy due to the friction made by porous structure of the material itself. Therefore, the acoustic performance of the sound absorbing material is inevitably influenced by the structural characteristics and mechanical properties of the material. At this time, the acoustical properties can be predicted using an acoustical model that describes The behavior of the soilid and fluid inside the material when sound waves are incident.
In our laboratory, measurement set up using impedance tube method is prepared. This method is compact and economical compared with other experimental method. Also the macro physical properties also measured or predictied by various method. With these properties we can predict the acoustical properties of the materials.
