木质阻尼多层复合结构设计对隔声性能的影响

Influence of the design of wood damped multilayer composite structures on sound insulation performance

在不改变板材厚度和面密度的前提下,通过优化木质阻尼多层复合材料的橡胶层数、结构的对称性、阻尼结构参数,提高木质阻尼多层复合材料的隔声性能。利用小混响室-消声箱法和DMA测试结构的隔声性能以及损耗因子。结果表明:在低频和高频范围内,非对称结构的隔声性能优于对称结构。非对称结构在共振频率的隔声量比对称结构的高4 d B,损耗因子几乎不变。随着橡胶层数增加复合材料的隔声性能增加,计权隔声量增加61%。橡胶层数的增加,抑制了复合材料共振现象,提高了共振频率处的隔声量。损耗因子从0.05增加到0.61,有效地抑制复合材料的吻合效应,使得复合材料的临界频率向高频移动。阻尼结构为自由阻尼结构的计权隔声量为27 d B,约束阻尼结构的计权隔声量为32 d B,提高了18.5%。在共振频率处,约束阻尼结构的隔声量大于自由阻尼结构。约束阻尼结构的损耗因子大于自由阻尼结构,损耗因子越大,可以有效地抑制吻合效应,提高隔声量。

The sound insulation performance of the wood damping multi-layered composite material was improved by designing the rubber layer number,the structure symmetry and the damping structure parameters of the wood damping multi-layered composite material without increasing the thickness and the surface density of the sheet.The use of small noise box and DMA test material sound insulation performance and loss factor.The results show that the sound insulation performance of the asymmetric structure is better than that of the symmetrical structure in the low frequency and high frequency range.Asymmetric structure in the resonant frequency of the sound insulation than the symmetrical structure of the high 4dB,loss factor almost unchanged.As the number of rubber layers increases,the sound insulation performance of the composite increases,and the weight of the weight increases an increase of 61%.With the increase of the number of rubber layers,the resonance of the composites is suppressed and the sound insulation at the resonant frequency is increased.The damping loss factor increases from 0.05 to 0.61,which effectively suppresses the anastomotic effect of the composite material,so that the critical frequency of the composite moves to high frequency.The weight of the composite damping structure is 27dB,and the weight of the damping structure is 32dB,which is 18.5%.At the resonant frequency,the sound insulation of the constrained damping structure is larger than that of the free damping structure.The loss factor of the constrained damping structure is larger than that of the free damping structure.The larger the loss factor can effectively suppress the anastomosis effect and improve the sound insulation.