Measurement of sound propagation in glass wool

Measurements of anisotropic sound propagation in glass wool

The attenuation coefficient and phase velocity of plane sound waves propagating in three perpendicular directions in glass wool were measured in the frequency range 50-10,000 Hz. For glass wool of mass density 14 kg/m3 at the frequency 1,000 Hz, the attenuation constant for propagation perpendicular to the glass wool sheets was 75 dB/m, and for propagation parallel with the sheets 57 dB/m. For ...

Measured anisotropic air flow resistivity and sound attenuation of glass wool.

The air flow resistivity of glass wool has been measured in different directions. The glass wool was delivered from the manufacturer as slabs measuring 100x600x900 mm3, where the surface 600x900 mm2 was parallel with the conveyor belt used in the manufacturing. Directions in the glass wool are described by a coordinate system with the X axis perpendicular to the conveyor belt, the Z axis in the...

Fiber movements and sound attenuation in glass wool

Analysis of Sound Propagation in Lined Ducts by means of a Finite Element Model

The present paper describes the results of a Finite Element Model used to analize sound propagation in lined ducts. By means of a numerical model it was possible to predict the insertion loss inside rectangular lined ducts in a frequency range from 250 Hz to 4000 Hz. The model was validated by a comparison with experimental data obtained in accordance to ISO 11691 and ISO 7235 standards. The so...

Acoustic propagation analysis in the front of saline water mass in the Gulf of Aden

Background and Objectives: Influence of water mass on sound propagation in the Gulf of Aden underwater acoustics used for communication, navigation and identification of objects by both humans and marine mammals and for investigating the detrimental effects of anthropogenic activities (e.g. pile driving, seismic survey and ships) on marine animals. The Gulf of Aden presents a unique ecosystem t...