木棉及其混合纤维非织造材料吸声预测模型

Predicting model of sound absorption for kapok-based fiber nonwoven fabrics

以Allard模型为基础,采用等效流体的方法,拟建立一个能够准确描述木棉及其混合纤维非织造材料吸声行为的吸声模型。该模型结合木棉纤维的大中空结构,考虑了材料的热传导效应及纤维框架的柔软性。使用新建立的吸声模型及Allard模型分别对4种不同结构的木棉纤维非织造材料的吸声系数及比表面阻抗进行了计算,并将计算值与实验样品的测量值进行比较。结果表明:新模型的计算结果更接近实验值,说明新模型更适用于木棉及其混合纤维非织造材料吸声性能的预测,为工业产品的设计提供了理论参考。

Aiming at kapok-based nonwoven fabrics,a new sound-absorbing model based on the Allard model is developed based on equivalent fluid method by considering the heat conduction performance of the materials and the limpness of the fiber frame. The sound absorption coefficients and specific surface impedance are calculated by the Allard model and the new model,respectively. The comparisons between the calculated and measured values for four types of kapok-based nonwoven fabrics are made. It is shown that the new model provides the predictions better than Allard model. This further indicates that the new model is suitable for the predicting of sound absorption for kapok-based nonwoven fabrics,and will lay the theoretical foundation for the design of industrial products for kapok materials.