Abstract:

In order to clarify the effect of pore characteristic on sound absorption behaviors of nonwovens, Sound absorption behaviors of six nonwovens are measured by SW260 double-microphones standing wave tube, and then their pore area fractal dimensions are calculated by box-counting method. The results indicate that increasing air gap improves the absorption coefficient on the tested frequency, and the absorption curve moves towards lower frequency. In addition, the results show that the pore structures of nonwovens have obvious fractal characteristics. The acoustic absorption coefficient grows linearly with increasing area fractal dimension, while the absorption peak moves towards lower frequency.