Glass wool belongs to a category of glass fiber, is a kind of artificial inorganic fiber. Using quartz sand, limestone, dolomite and other natural ores as the main raw materials, combined with some soda ash, borax and other chemical raw materials to melt glass. In the melting state, with the help of external force blowing, flocculent fine fibers are spun. The fibers intersect and intertwine with each other, showing many small gaps. This gap can be regarded as a pore. Therefore, glass wool can be regarded as a porous material with good thermal insulation and sound absorption properties.

　　When the thickness is constant, the bulk density increases, and the absorption coefficient of medium and low frequency also increases; However, when the bulk density of glass wool increases to a certain extent, the material becomes dense, the flow resistance is greater than the good flow resistance, and the sound absorption coefficient decreases. For the centrifugal glass wool with a bulk density of 16KG / m3 and a thickness of more than 5cm, the sound absorption coefficient of 125Hz at low frequency is about 0.2, and the sound absorption coefficient at medium and high frequency （> 500Hz） is close to 1.

　　When the thickness increases from 5cm, the absorption coefficient of low frequency gradually increases. When the thickness is more than 1m, the absorption coefficient of low frequency 125Hz will be close to 1. When the thickness is constant and the bulk density is increased, the low-frequency sound absorption coefficient of centrifugal glass wool will continue to increase. When the bulk density is close to 110kg / m3, the sound absorption performance reaches a high value, which is close to 0.6-0.7 at the thickness of 50mm and the frequency of 125Hz.