Investigation of sound absorption properties of nonwoven webs produced from chicken feather fibers

As a consequence of modern life and technology, noise causes many negative side effects, especially with regard to health. Today, the presence of acoustic problems in transport vehicles such as airplanes, cars and train wagons has become one of the major problems of modern life. Many methods and materials have been developed to provide acoustic comfort in indoor spaces. One of them is the development and application of sound-absorbing materials. Nonwoven webs, which are considered to be the most ideal materials for sound insulation, have micron-sized pores as well as large surface areas. Among these materials, materials with double-layered porosity have greater effect. In recent years, researchers are increasingly turning to the development of sound-absorbing materials from production waste and natural materials that are easily decomposed in the environment. In this study, the sound-absorbing properties of nonwoven webs produced from chicken feather fibers, a by-product in chicken production and a significant amount of waste, were investigated. For this purpose, nonwoven web samples with different parameters were produced by using different binding materials by using thermal bonding method. The sound absorption coefficient and sound transmission loss values of the samples were measured and evaluated. As a result of the analyses, the influence parameters such as thickness, bulk density and porosity on the sound insulation properties of the produced samples was revealed. The assumptions concerning the mechanism of sound insulation of nonwoven webs produced from chicken feather fibers are detailed. Studies have shown that nonwoven webs from chicken feather fibers can be used as soundproof materials because of their good sound-absorbing properties.

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Non-Wovens as Sound Reducers

Latvian Journal of Physics and Technical Sciences ◽

10.2478/lpts-2018-0014 ◽

2018 ◽

Vol 55 (2) ◽

pp. 64-76

Author(s):

D. Belakova ◽

A. Seile ◽

S. Kukle ◽

T. Plamus

Keyword(s):

Absorption Coefficient ◽

Surface Density ◽

Sound Absorption ◽

Transmission Loss ◽

Sound Transmission ◽

Sound Insulation ◽

Material Structure ◽

Sound Transmission Loss ◽

Sound Waves ◽

Frequency Range

Abstract Within the present study, the effect of hemp (40 wt%) and polyactide (60 wt%), non-woven surface density, thickness and number of fibre web layers on the sound absorption coefficient and the sound transmission loss in the frequency range from 50 to 5000 Hz is analysed. The sound insulation properties of the experimental samples have been determined, compared to the ones in practical use, and the possible use of material has been defined. Non-woven materials are ideally suited for use in acoustic insulation products because the arrangement of fibres produces a porous material structure, which leads to a greater interaction between sound waves and fibre structure. Of all the tested samples (A, B and D), the non-woven variant B exceeded the surface density of sample A by 1.22 times and 1.15 times that of sample D. By placing non-wovens one above the other in 2 layers, it is possible to increase the absorption coefficient of the material, which depending on the frequency corresponds to C, D, and E sound absorption classes. Sample A demonstrates the best sound absorption of all the three samples in the frequency range from 250 to 2000 Hz. In the test frequency range from 50 to 5000 Hz, the sound transmission loss varies from 0.76 (Sample D at 63 Hz) to 3.90 (Sample B at 5000 Hz).

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An improved approach for normal-incidence sound transmission loss measurement using a four-microphone impedance tube

Journal of Vibration and Control ◽

10.1177/1077546320926905 ◽

2020 ◽

pp. 107754632092690

Author(s):

Zechao Li ◽

Sizhong Chen ◽

Zhicheng Wu ◽

Lin Yang

Keyword(s):

Transfer Matrix ◽

Sound Absorption ◽

Transmission Loss ◽

Sound Transmission ◽

Normal Incidence ◽

Sound Insulation ◽

Sound Transmission Loss ◽

The Common ◽

Wavefield Decomposition ◽

Insulation Performance

The main aim of this study is to introduce an improved method for determining the sound properties of acoustic materials which is more precise than the common wavefield decomposition method and simpler than the common transfer matrix method. In the first part of the article, a group of formulae for calculating sound transmission loss is represented by combining the wavefield decomposition and transfer matrix methods. Subsequently, a formula for calculating sound absorption coefficients is derived from these formulae by definition. Furthermore, the present formulae are validated by comparing the experimental results achieved with the present formulae and those results obtained by other methods recorded in published articles. Eventually, it is demonstrated that the method can accurately measure the sound insulation performance of materials and the sound absorption properties of limp and lightweight materials.

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Exploration and optimization on the usage of micro-perforated panels as trim panels in commercial aircrafts

Noise Control Engineering Journal ◽

10.3397/1/37687 ◽

2020 ◽

Vol 68 (1) ◽

pp. 87-100

Author(s):

L.I. Chenxi ◽

H.U. Ying ◽

H.E. Liyan

Keyword(s):

Absorption Coefficient ◽

Sound Absorption ◽

Transmission Loss ◽

Sound Absorption Coefficient ◽

Aviation Industry ◽

Sound Insulation ◽

Aircraft Cabins ◽

Aircraft Cabin ◽

Specific Frequency ◽

Trim Panel

Micro-perforated panels (MPPs), as an alternative to porous materials for sound absorption, have been commonly used in electronic industries and aircraft engines but are barely used in aircraft cabins. The effect of MPPs on the sound insulation and absorption properties of aircraft cabin panels has been investigated in this article. Theoretical modeling has been conducted on an aircraft cabin panel structure with a trim panel replaced by an MPP trim panel, using the transfer matrix method and the classic MPP theory. It is indicated by the theoretical results that, although the sound transmission loss (STL) of the cabin panel with an MPP trim panel is lower than that with an un-perforated panel, the MPP trim panel can significantly enhance the sound absorption coefficient of the entire cabin panel structure. Based on the well-developed MPP theory, the sound absorption coefficient of an aircraft cabin panel with an MPP trim panel can be improved by optimizing the MPP's parameters at a specific frequency. Taking an engine frequency 273 Hz as an example, the optimization can increase the sound absorption coefficient to 1 by using the doublelayered MPPs. When the thermal acoustic insulation blanket is considered, although the STL of the proposed structure with double-layered MPP trim panels in a diffuse field is lower than those without MPP trim panels, the sound absorption in the cabin is significantly enhanced due to the double-layer MPP trim panel at the specific engine frequency and across all frequencies. The STL of the structure with double-layered MPP trim panels and TAIB can be higher than 40 dB from 880 Hz in a diffuse field, which implies its effectiveness as sound insulation structure in aviation industry. MPP trim panels provide a new idea for the design of aircraft cabin panels and areworthy of further research

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Incorporation of Nanofiber Layers in Nonwoven Materials for Improving Their Acoustic Properties

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892501300800412 ◽

2013 ◽

Vol 8 (4) ◽

pp. 155892501300800 ◽

Cited By ~ 2

Author(s):

Amir Rabbi ◽

Hossein Bahrambeygi ◽

Ahmad Mousavi Shoushtari ◽

Komeil Nasouri

Keyword(s):

Sound Absorption ◽

Transmission Loss ◽

Sound Transmission ◽

Wide Band ◽

Acoustic Properties ◽

Sound Insulation ◽

Sound Transmission Loss ◽

Factors Affecting ◽

Nonwoven Materials ◽

Field Noise

Due to numerous developments in most industries and the increase in the usage of massive and powerful machines in every field, noise has become an unavoidable part of mechanized life and has brought about serious health hazards. The main aim of this work was to investigate the usability of polyurethane and polyacrylonitrile nanofibers for improving sound insulation properties over a wide band of frequencies and reducing weight and thickness of conventional polyester and wool nonwovens. The effect of the number of nanofiber layers and associated surface densities on acoustic properties was investigated. Sound transmission loss and sound absorption analysis using the impedance tube method were carried out as the main factors affecting acoustic behavior of samples. The results show that incorporation of nanofiber layers in nonwoven materials can improve both sound absorption and sound transmission loss simultaneously, especially in mid and lower frequencies, which are difficult to detect by conventional materials.

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SOUND ABSORPTION OF SOUND SUPRESSING LIGHTWEIGHT STRUCTURED PANELS

Akustika ◽

10.36336/akustika20193440 ◽

2019 ◽

Vol 34 ◽

pp. 40-43

Author(s):

Valery Murzinov ◽

Pavel Murzinov ◽

Sergey Popov ◽

Julia Taratinova

Keyword(s):

Absorption Coefficient ◽

Surface Density ◽

Sound Absorption ◽

Sound Absorption Coefficient ◽

Sound Insulation ◽

Acoustic Characteristics ◽

Absorbing Materials

Description of the effective soundproofing panel is presented. For this panel, the ratio of acoustic characteristics and surface density exceeds many modern sound insulation and sound absorbing materials and structures. This article is devoted to modeling the sound absorption coefficient of the soundproof panel. The article presents formulas for determining the coefficient of sound absorption. Construction of a sound suppressed lightweight structured panel (SSLSP) developed by the authors is shown. Comparison of the effectiveness of the SSLSP panel and modern sound-proof materials is shown.

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Design of Nonwoven Carpets to Upgrade Sound Isolation Features in Automobiles

Autex Research Journal ◽

10.2478/aut-2014-0027 ◽

2014 ◽

Vol 14 (4) ◽

pp. 270-280 ◽

Cited By ~ 4

Author(s):

Raziye Atakan ◽

Hale Karakaş ◽

Serdar Sezer ◽

Süleyman İpek ◽

İpek Aravi ◽

...

Keyword(s):

Mechanical Properties ◽

Sound Absorption ◽

Transmission Loss ◽

Sound Transmission ◽

Sound Insulation ◽

Frequency Range ◽

Absorption Coefficients ◽

Floor Coverings ◽

Effective Part ◽

Heavy Layer

Abstract With the increases of the expected properties of textile products, better and advanced new designs are being created. Textiles used in vehicles are increasing, and the current performance of the expectations bar is determined by automobile manufacturers. While meeting the expectations of users in the vehicle mechanically, but also disturbing the user during operation of the mechanical properties of this ratio should be minimized. This study was intended to minimize sound transmission of nonwoven textile components, which are used in cars as silencer parts. For that purpose, four different models were developed in this study. First model consists of three designs for baggage carpets. Second model has six designs for floor coverings. Third model comprises two designs inner dash felt and finally fourth model includes two designs of hood liners. The acoustical absorption coefficients and transmission loss of these carpets were tested and evaluated in the frequency range of 16-6300 Hz. The measurements demonstrated that nonwoven layer is a very significant and effective part of a carpet due to its contribution in the sound isolation. With this study, it has been determined which layer has better performance on sound absorption and transmission loss among different carpet types. A combination of heavy layer and nonwoven layer carpets is found to be benefit for noise and sound insulation.

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DETERMINING ACOUSTIC EFFICIENCY OF MATERIALS AND STRUCTURES IN LABORATORY AND REAL CONDITIONS PART 1: SOUND ABSORPTION AND SOUND INSULATION

TsAGI Science Journal ◽

10.1615/tsagiscij.2018029529 ◽

2018 ◽

Vol 49 (8) ◽

pp. 841-859

Author(s):

Aleksander Yakovlevich Zverev ◽

Valerii Vasil'evich Chernyh

Keyword(s):

Sound Absorption ◽

Sound Insulation

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Factors Affecting Acoustic Properties of Natural-Fiber-Based Materials and Composites: A Review

Textiles ◽

10.3390/textiles1010005 ◽

2021 ◽

Vol 1 (1) ◽

pp. 55-85

Author(s):

Tufail Hassan ◽

Hafsa Jamshaid ◽

Rajesh Mishra ◽

Muhammad Qamar Khan ◽

Michal Petru ◽

...

Keyword(s):

Sound Absorption ◽

Natural Fiber ◽

Volume Fraction ◽

Fiber Type ◽

Alkali Treatment ◽

Acoustic Properties ◽

Synthetic Fiber ◽

Sound Insulation ◽

Factors Affecting ◽

Wide Range

Recently, very rapid growth has been observed in the innovations and use of natural-fiber-based materials and composites for acoustic applications due to their environmentally friendly nature, low cost, and good acoustic absorption capability. However, there are still challenges for researchers to improve the mechanical and acoustic properties of natural fiber composites. In contrast, synthetic fiber-based composites have good mechanical properties and can be used in a wide range of structural and automotive applications. This review aims to provide a short overview of the different factors that affect the acoustic properties of natural-fiber-based materials and composites. The various factors that influence acoustic performance are fiber type, fineness, length, orientation, density, volume fraction in the composite, thickness, level of compression, and design. The details of various factors affecting the acoustic behavior of the fiber-based composites are described. Natural-fiber-based composites exhibit relatively good sound absorption capability due to their porous structure. Surface modification by alkali treatment can enhance the sound absorption performance. These materials can be used in buildings and interiors for efficient sound insulation.

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