The vibration sound absorption theory for thin fiber layers

摘要

Nowadays, we still use the Rayleigh model to explain the sound absorption principle for fibrous material. Based on Rayleigh model, Zwikker and Kosten established the theory of effective density and the effective bulk modulus 50 years ago. Although the theory has been studied for over 100 years, both the Rayleigh model and Zwikker and Kosten theory can not get the exact results to agree with the practice. A new theory which applied membrane vibration theory for the thin fibrous material was put forward that fibrous material absorbs the sound by the fiber's vibration while not the aperture in it. It was proved that the vibration theory obtained by the membrane vibration analyze well agreement with test result of 30 kinds of nonwovens and fabrics.