黏弹性泡沫多孔材料骨架特征参数对材料吸声性能的影响

Influence of frame parameters of viscoelastic foams on sound-absorbing performance

基于Biot理论,研究了黏弹性多孔材料体积模量、损耗因子和骨架密度三个特征参数对吸声性能的影响规律。针对实际三聚氰胺泡沫材料,应用准静态法测量出其杨氏模量和泊松比,并根据上述规律推断出测到的骨架参数对阻尼和黏性耗散影响。为了进行验证,进一步测量出材料的静流阻率,并根据Dunn-Davern模型计算出有效密度和压缩模量。根据以上参数计算出刚性背衬下的材料吸声系数,在与实验值一致的情况下,进一步分解为阻尼、黏性和热传导耗散,其变化特征表明该材料阻尼耗散较小,共振现象明显,在1/4波长共振频率附近会引起黏性耗散和总吸声明显减少。

The influence of frame parameters of poro-viscoelastic materials, including bulk modulus, loss factor, and frame density, on sound-absorbing performance was investigated based on the Biot theory. A quasi-static method was used to measure Young’s modulus and Poisson’s ratio of a melamine foam. Their influence on sound-absorbing performance was also investigated in terms of these parameters. In addition, the effective density and bulk modulus of the foam were calculated by a model based on static resistivity developed by Dunn and Davern. When sound absorption of the foam with rigid backing was measured, our experiments were consistent with calculated absorption coefficients, which were further decomposed into parts due to damping, viscous, and heat transfer losses. The results show that the damping loss of the foam is small, while the viscous and total losses are significantly reduced around the quarter wavelength resonance frequency.