Aiming at the problems of poor noise reduction performance and low strength of light and thin fiber assembly materials,this paper proposes the design concept of absorption matching layer,absorption layer and reflective layer,and constructs acoustic models with different structural parameters and noise reduction mechanisms.Based on the composite noise reduction technology,a noise-reducing flexible textile composite material with sound absorption and insulation functions,good mechanical properties,and light weight was designed and prepared.The main research contents are as follows:First of all,in order to deeply analyze the influence of structure and performance parameters on the noise reduction performance of materials.Based on acoustic principles and related parameters,combined with the testing principles of test instruments,this research establishes acoustic models of porous materials,resonance materials,film materials and flexible composite materials with different sound absorption and sound insulation mechanisms,and discusses the influence of various factors on the sound absorption performance and sound insulation performance of the noise reduction flexible composite material in the case of single or combination of each layer material.And the material is designed and prepared according to the results of model simulation calculation,which provides a theoretical basis for the scientific design and preparation of multi-layer structure noise-reducing flexible textile composite materials.Secondly,according to the simulation results of different acoustic models,combined with the characteristics of textile materials,the optimization scheme of noise reduction performance of flexible textile composite materials is proposed,and the absorption matching layer,absorption layer and reflection layer materials are designed and prepared respectively,and their noise reduction mechanism is analyzed.Combined with the material’s resonance sound absorption principle,heat loss principle and the matching effect between materials,flexible perforated composite materials and flexible film composite materials are prepared.The influence of perforation rate,perforation diameter,fiber felt thickness and cavity depth of perforated materials and foam rate,particle content and film thickness of film composites on the sound absorption performance were systematically studied.Combining the advantages of polymer materials with viscoelasticity and good formability,the sound insulation performance of polyurethane membrane composites filled with particles of different densities,shapes and particle sizes was systematically studied.And through a large number of experimental data to derive the sound insulation formula of the polyurethane film composite material,as a guide for the preparation of the reflective layer in the multilayer structure noise-reducing flexible textile composite material.Finally,according to the simulation and experimental results,the noise-reducing flexible textile composite material was prepared.The results show that the prepared multilayer noise reduction material has good sound absorption and sound insulation properties while maintaining fiber felt light,soft features at the same time,has a good performance of sound absorption,sound insulation performance,mechanical properties and dielectric properties,which has broad application prospects in curtains,wall coverings,interiors of automobiles and vehicles,construction,roads,military and other fields. |