Sound insulation of glass fiber felt composite structure via the flame blowing process

Glass fiber felt has emerged as a popular material for noise reduction. In this paper, glass fiber felt is produced by flame blowing process. Fiber distribution, microstructure, permeation rate and sound transmission loss (STL) are explored. The results show that, the internal and cross-sectional structures of glass fiber felt are disordered and micro-layer, respectively. There is a directly proportional relationship between fiber diameter and permeation rate. For composite structure, if the face sheet of glass fiber felt with high reflection coefficient, STL of composite structure can be improved. It is also found that STL can be improved by increasing the number of air-layers. However, the influence of the position changing of air-layer can be ignored for STL.