Fiberglass Wool Roll Heat Insulation Material Blanket 48kg/M3 Glasswool 25mm 50mm

Fiberglass Wool Roll Heat Insulation Material Blanket 48kg/m3 Glasswool 25mm 50mm Glass Wool Price

Centrifugal glass wool is a porous sound-absorbing material with good sound absorption properties. Centrifugal glass wool can absorb sound not because of the rough surface, but because there are a large of tiny pores and holes connected inside and outside. When sound waves are incident on the centrifugal glass wool, the sound waves can follow the pores into the interior of the material, causing the vibration of air molecules in the gaps. Due to the viscous resistance of air and air molecules and the friction of the pore wall, sound energy is converted into heat energy and loss.

Sound absorption performance

Centrifugal glass wool has good sound absorption performance for sound in high frequency. The main factors affecting the sound absorption performance of centrifugal glass wool are thickness, density and air flow resistance. Density is the weight of the material per cubic meter. Air flow resistance is the ratio of air pressure and air flow rate on both sides of the material at unit thickness. Air flow resistance is the most important factor affecting the sound absorption performance of centrifugal glass wool. Flow resistance is too small, indicating that the material is sparse, air vibration is easy to pass through, the sound absorption performance decreases; flow resistance is too large, indicating that the material is dense, air vibration is difficult to pass into, the sound absorption performance also decreases. For centrifugal glass wool, the best flow resistance exists for sound absorption performance.

In actual engineering, it is difficult to determine the air flow resistance, but can be roughly estimated and controlled by the thickness and weight.

1, as the thickness increases, the low frequency absorption coefficient increases significantly, but the high frequency change is not large (high frequency absorption is always larger).

2, the thickness remains the same, the capacity increases, the low frequency absorption coefficient also increases; but when the capacity increases to a certain extent, the material becomes dense, the flow resistance is greater than the best flow resistance, the absorption coefficient decreases instead. For the thickness of more than 5cm of 16Kg/m3 of centrifugal glass wool, low frequency 125Hz is about 0.2, high frequency (>500Hz) absorption coefficient is close to 1. When the thickness continues to increase from 5cm, the absorption coefficient of low frequency gradually increases, when the thickness is greater than 1m or more, the absorption coefficient of low frequency 125Hz will also be close to 1. When the thickness remains unchanged and the capacity increases, the low frequency absorption coefficient of centrifugal glass wool will also continue to improve, when the capacity is close to 110kg/m3 sound absorption performance reaches its maximum, 50mm thick, frequency 125Hz at close to 0.6- 0.7. When the capacity exceeds 120kg/m3, the sound absorption performance decreases, because the material becomes dense and the medium and high frequency sound absorption performance is greatly affected, and when the capacity exceeds 300kg/m3, the sound absorption performance decreases a lot. The thickness of acoustic glass wool commonly used in building acoustics are 2.5cm, 5cm, 10cm, with a capacity of 16, 24, 32, 48, 80, 96, 112kg/m3. 5cm thick, 12-48kg/m3 centrifugal glass wool is usually used.