梯度纤维多孔材料的吸声特性及结构优化

Sound Absorption Characteristics and structure optimization of Gradient Fibrous Porous Materials

摘要:

利用金属纤维为原料,制成内部具有梯度孔结构的金属纤维多孔吸声材料,梯度孔结构可分为孔隙度梯度和丝径梯度,本文分别研究了这两种梯度结构的吸声特性。结果表明,厚度在6mm~30mm范围内时,孔隙度梯度结构按照孔隙度从大到小的顺序排列有利于提高全频的吸声性能；厚度为3mm时,孔隙度梯度结构的排列规律恰好相反；丝径梯度结构的特点是当厚度为3mm时,细丝径纤维多孔材料在前,全频吸声性能较好,随着厚度的增加,当厚度≥20mm时,粗丝径纤维多孔材料在前,全频吸声性能好,在3mm~20mm之间,两种排列方式的丝径梯度结构的吸声频率曲线存在一个交点,随着厚度的增加,该交点逐渐向低频方向移动。

Abstract:

Using metal fibrous to prepare sound absorption materials, the pore inner this material presented gradient arrangement. The gradient pore structure can be carved up two kinds, porosity gradient structure (PGS) and fiber diameter gradient structure (FGS). In this paper, the sound absorption characteristics of two kinds of these structures were studied. The results indicate that when the thickness higher than 6mm, the porosity of the PGS according to from high to low, can be enhanced the sound absorption performance in the whole frequency range at 50Hz to 6400Hz. But this law is just opposite to the thinner PGS when thickness is about 3mm. The characteristic of the FGS is when the thin fiber ahead the structure (3mm), the sound absorption performance is very well for the thicker structure in whole frequency, and when the thick fiber ahead the structure (≥20mm), the sound absorption performance is very well for the thinner structure in whole frequency. When the thickness at the range from 3mm to 20mm, there is a point of intersection between the sound absorption and frequency curves of the FGS with two kinds of arrange way.