Construction Of Noise Reduction Structure And Sound Absorption Mechanism Of Thin Flexible Fiber Material

With the progress of society and the development of science and technology,people have higher and higher requirements for the functionality of textiles.Decorative textiles are an important category of textile products,and while they meet aesthetic needs,people also want them to have multiple functions.Curtains and other decorative textiles are the largest indoor area of fiber products.and fiber materials are commonly used to absorb sound and reduce noise,people hope that curtains in addition to meeting the function of light blocking,heat preservation,etc.,but also has a certain effect of noise reduction.However,the noise reduction effect of such porous sound-absorbing mechanism structural body as fiber products has a serious thickness dependence.How to improve the sound absorption performance of thin fiber structures such as fabrics remains to be studied.This topic takes woven fabric as the object,oriented to the curtain fabric application scenario,analyzes the relationship between the pore structure characteristics of the thin fiber structure body and its sound absorption performance,investigates the effect of the fabric backing air layer on the sound absorption effect and its mechanism of action,and constructs the sound absorption model of the woven structure fiber aggregate.It is found that when the difference of fabric porosity is less than 3%,the sound absorption performance of the inverted gradient structure is better than that of the positive gradient structure when the difference of porosity between layers is larger,the sound absorption performance of the positive gradient structure is better than that of the inverted gradient structure,and the larger the difference,the better the sound absorption effect.In addition,the sound absorption performance of the double-layer fabric obtained by direct weaving is better than that of the two-layer fabric composite.It is shown that with the increase of the thickness of the backed air layer,the sound absorption band of the fabric and air layer forming the absorbing structural body becomes wider,and the frequency corresponding to the peak of the absorption coefficient shifts to the middle and low frequencies.The fabric vibration improvement model and Pieren model with the addition of fabric structure parameters can better predict the variation trend of the absorption curve of the thin fabric structure body with the back air layer,and the prediction accuracy increases.In order to make more accurate prediction of the sound absorption performance of the thin fabric structural body with backing air layer,a two-dimensional porous fabric structural body sound absorption model was established,and the results showed that the predicted and measured values had correlation,with the correlation coefficient R~2 greater than 0.95;thus,the influence of the fabric structure parameters on the sound absorption performance of the structural body was analyzed,and it was found that the thickening of the backing air layer had an effect similar to that of increasing the material thickness,and the thin fabric had the best flow resistance.It is found that the thickening of the backing air layer has an effect similar to that of increasing the thickness of the material,and the thin fabric has the best flow resistance,which can make the structure achieve the best sound absorption effect.