Glass wool insulation board with a bulk density of 48K

Glass wool insulation board with a bulk density of 48K

Centrifugal glass wool has good sound absorption performance for high frequencies in sound. The main factors affecting the sound absorption performance of centrifugal glass wool are thickness, density, and air flow resistance. Density is the weight per cubic meter of material. Air flow resistance is the ratio of air pressure and air velocity on both sides of a material per unit thickness. Air flow resistance is an important factor affecting the sound absorption performance of centrifugal glass wool. If the flow resistance is too small, it indicates that the material is sparse, and air vibration is easy to pass through, resulting in a decrease in sound absorption performance; If the flow resistance is too high, it indicates that the material is dense, making it difficult for air vibrations to be transmitted, and the sound absorption performance also decreases. For centrifugal glass wool, there is flow resistance in its sound absorption performance.

In practical engineering, it is difficult to measure air flow resistance, but it can be roughly estimated and controlled through thickness and bulk density.

1As the thickness increases, the mid low frequency sound absorption coefficient significantly increases, but there is little change in high frequency (high frequency absorption is always large).

2The thickness remains unchanged, the bulk density increases, and the mid low frequency sound absorption coefficient also increases; But when the bulk density increases to a certain extent, the material becomes denser, the flow resistance is greater than the flow resistance, and the sound absorption coefficient actually decreases. For thicknesses exceeding5cmThe bulk density is16Kg/m3Centrifugal glass wool, low frequency125Hzapproximately0.2Mid to high frequency（>500Hz）The sound absorption coefficient has approached1That's it. When the thickness is5cmAs it continues to increase, the low-frequency sound absorption coefficient gradually increases, and when the thickness is greater than1mWhen above, low frequency125HzThe sound absorption coefficient will also be close to1When the thickness remains constant and the bulk density increases, the low-frequency sound absorption coefficient of centrifugal glass wool will also continue to increase. When the bulk density approaches110kg/m3When the sound absorption performance reaches its maximum value,50mmThickness and frequency125HzApproaching here0.6-0.7The bulk density exceeds120kg/m3When the density of the material increases, the sound absorption performance actually decreases because the material becomes denser, which greatly affects the mid to high frequency sound absorption performance. When the bulk density exceeds300kg/m3At that time, the sound absorption performance decreased significantly. The thickness of commonly used sound-absorbing glass wool in architectural acoustics includes2.5cmThe5cmThe10cmThe bulk density is16、24、32、48、80、96The112kg/m3. Usually used5cmThick,12-48kg/m3Centrifugal glass wool.Glass wool insulation board with a bulk density of 48K