Measuring Methods of Acoustic Properties and Influence of Physical Parameters on Natural Fibers: A Review

From a circular economy perspective, the acoustic characterization of steelwork by-products is a topic worth investigating, especially because little or no literature can be found on this subject. The possibility to reuse and add value to a large amount of this kind of waste material can lead to significant economic and environmental benefits. Once properly analyzed and optimized, these by-products can become a valuable alternative to conventional materials for noise control applications. The main acoustic properties of these materials can be investigated by means of a four-microphone impedance tube. Through an inverse technique, it is then possible to derive some non-acoustic properties of interest, useful to physically characterize the structure of the materials. The inverse method adopted in this paper is founded on the Johnson–Champoux–Allard model and uses a standard minimization procedure based on the difference between the sound absorption coefficients obtained experimentally and predicted by the Johnson–Champoux–Allard model. The results obtained are consistent with other literature data for similar materials. The knowledge of the physical parameters retrieved applying this technique (porosity, airflow resistivity, tortuosity, viscous and thermal characteristic length) is fundamental for the acoustic optimization of the porous materials in the case of future applications.

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A statistical analysis of low-stress mechanical properties of warp-knitted fabrics

Textile Research Journal ◽

10.1177/0040517516681963 ◽

2016 ◽

Vol 88 (4) ◽

pp. 467-479 ◽

Cited By ~ 3

Author(s):

Ka-yan Yim ◽

Chi-wai Kan

Keyword(s):

Mechanical Properties ◽

Evaluation System ◽

Natural Fibers ◽

Physical Parameters ◽

Knitted Fabrics ◽

Fabric Hand ◽

Low Stress Mechanical Properties ◽

Fabric Weight ◽

Fabric Structures ◽

Selection Of

Fabric hand is an indispensable characteristic for the selection of fabric and product development and the buying consideration for manufacturers and consumers. However, there is little comprehensive work on the hand feel property of warp-knitted fabrics due to the mainstream natural fibers (cotton, wool and silk) and other fabric structures (woven, weft-knitted and nonwoven). The increasing potential for the wide variety of applications and development of warp-knitted fabrics is not only because its fabric hand gives better determination for fabric marketing, but also because it provides extensive scope for fabric performance and appearance. This paper reports an experimental study on the integrated fabric hand behavior of a series of warp-knitted fabrics made for various apparel applications, such as sportswear, lingerie and leisure wear. These 105 fabrics were produced by varying different physical parameters, including fabric weight and fabric thickness. The Kawabata Evaluation System for Fabric (KES-F) was employed to obtain the fabric hand properties (primary hand value and total hand value) related with stiffness, smoothness and softness. All low-stress mechanical properties and fabric hand values from the testing results were used to verify the applicability of the KES-F on warp-knitted fabrics and to analyze the relationships of fabric parameters and hand characteristics. The results indicate that the KES-F is an appropriate tool to measure the hand attributes of warp-knitted samples, and moderate correlations between physical properties and mechanical behavior were found.

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Organized Framework of Main Possible Applications of Sheep Wool Fibers in Building Components

Sustainability ◽

10.3390/su12030761 ◽

2020 ◽

Vol 12 (3) ◽

pp. 761 ◽

Cited By ~ 1

Author(s):

Monica C.M. Parlato ◽

Simona M.C. Porto

Keyword(s):

Bacterial Load ◽

Natural Fibers ◽

Green Building ◽

Production Costs ◽

Acoustic Properties ◽

Wool Fibers ◽

Rural Buildings ◽

Building Components ◽

High Bacterial Load ◽

Sheep Wool

Greasy sheep wool is currently considered a special waste for its high bacterial load, with expensive disposal costs for sheep breeders. For this reason, wool is often burned or buried, with serious consequences for the environment. On the other hand, sheep wool is well regarded as one of the most performative insulating natural fibers due to its thermo-hygrometric and acoustic properties. In the building sector, sheep wool meets the requirements of green building components because it is an eco-friendly material, there is a surplus of it, it is annually renewable, and totally recyclable. If used instead of common insulation materials (e.g., fiberglass, rock wool, polyurethane foam, polystyrene), sheep wool offers significant benefits for sustainability such as a reduction in the production costs for new insulating materials and in environmental pollution. Mechanical and physical properties of sheep wool investigated in previous studies were assessed and discussed with the aim of providing an organized framework of possible applications of wool fibers in building components. This paper highlights in detail aspects that have not yet been investigated enough to detect new potential uses of sheep wool fibers in rural buildings and the reuse of traditional ones.

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Sound absorbing and insulating properties of natural fiber hybrid composites using sugarcane bagasse and bamboo charcoal

Journal of Engineered Fibers and Fabrics ◽

10.1177/15589250211044818 ◽

2021 ◽

Vol 16 ◽

pp. 155892502110448

Author(s):

Santhanam Sakthivel ◽

Selvaraj Senthil Kumar ◽

Eshetu Solomon ◽

Gedamnesh Getahun ◽

Yohaness Admassu ◽

...

Keyword(s):

Composite Materials ◽

Physical Properties ◽

Sugarcane Bagasse ◽

Sound Absorption ◽

Natural Fiber ◽

Natural Fibers ◽

Acoustic Properties ◽

Sound Insulation ◽

Bamboo Charcoal ◽

Green Composite

This research paper reports a study on thermal and sound insulation samples developed from sugarcane bagasse and bamboo charcoal for automotive industry applications. The sugarcane bagasse and bamboo charcoal fiber is a potential source of raw material that can be considered for thermal and sound insulation applications. Natural fibers are commonly used in diverse applications and one of the most important applications is sound absorption. Natural fiber hybrid composite currently is in greater demand in industries because of their advantages such as low cost, biodegradability, acceptable physical properties, and so on. Eco-friendly sound-absorbing composite materials have been developed using bamboo charcoal and sugarcane bagasse fibers. From these fibers five types of natural fiber green composite were developed using the compression bonding technique. The natural composite noise control performance contributes to its wider adoption as sound absorbers. The sound absorption coefficient was measured according to ASTM E 1050 by the Impedance tube method. The physical properties of natural fiber composites such as thickness, density, porosity, air permeability, and thermal conductivity were analyzed for all samples in accordance with ASTM Standard. The result exposed that natural fiber green composite were absorbing the sound resistance of more than 70% and the natural fibers composites provide the best acoustic absorption properties, these composite materials have adequate moisture resistance at high humidity conditions without affecting the insulation and acoustic properties.

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Acoustic Properties of a New Composite Material Obtained from Feather Flour and Recycled Polypropylene

Materiale Plastice ◽

10.37358/mp.21.4.5534 ◽

2022 ◽

Vol 58 (4) ◽

pp. 84-93

Author(s):

Mirela Alina Constantin ◽

Lucian Alexandru Constantin ◽

Sebastian Aradoaei ◽

Mihaela Aradoaei ◽

Mihai Bratu ◽

...

Keyword(s):

Electron Microscopy ◽

Natural Fibers ◽

Adsorption Properties ◽

Point Of View ◽

Acoustic Properties ◽

Gravimetric Analysis ◽

Thermal Gravimetric ◽

Recycled Polypropylene ◽

Sustainable Materials ◽

Scanning Electron

Sustainable materials made from recycled materials are an alternative to traditional materials (synthetic ones) and present a lower environmental impact. Due to the fact that natural fibers were successfully used to produce environmentally friendly sound adsorbing materials, biocomposites made from recycled polypropylene (PPR), feathers flour (FF) with / without compatibilizers (C) were obtained and characterized from the point of view of their acoustical behavior. Obtained materials were characterized also from the morphological and compositional point of view by scanning electron microscopy and thermal gravimetric analysis. All tested samples presented sound adsorption properties but the best results were obtained for the biocomposites with FF content of 10%-20%.

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Recent Developments in Luffa Natural Fiber Composites: Review

Sustainability ◽

10.3390/su12187683 ◽

2020 ◽

Vol 12 (18) ◽

pp. 7683

Author(s):

Mohamad Alhijazi ◽

Babak Safaei ◽

Qasim Zeeshan ◽

Mohammed Asmael ◽

Arameh Eyvazian ◽

...

Keyword(s):

Vibration Isolation ◽

Natural Fiber ◽

Volume Fraction ◽

Natural Fibers ◽

Weight Ratio ◽

Fiber Composites ◽

Acoustic Properties ◽

Natural Fiber Composites ◽

Synthetic Fibers ◽

Recent Developments

Natural fiber composites (NFCs) are an evolving area in polymer sciences. Fibers extracted from natural sources hold a wide set of advantages such as negligible cost, significant mechanical characteristics, low density, high strength-to-weight ratio, environmental friendliness, recyclability, etc. Luffa cylindrica, also termed luffa gourd or luffa sponge, is a natural fiber that has a solid potential to replace synthetic fibers in composite materials in diverse applications like vibration isolation, sound absorption, packaging, etc. Recently, many researches have involved luffa fibers as a reinforcement in the development of NFC, aiming to investigate their performance in selected matrices as well as the behavior of the end NFC. This paper presents a review on recent developments in luffa natural fiber composites. Physical, morphological, mechanical, thermal, electrical, and acoustic properties of luffa NFCs are investigated, categorized, and compared, taking into consideration selected matrices as well as the size, volume fraction, and treatments of fibers. Although luffa natural fiber composites have revealed promising properties, the addition of these natural fibers increases water absorption. Moreover, chemical treatments with different agents such as sodium hydroxide (NaOH) and benzoyl can remarkably enhance the surface area of luffa fibers, remove undesirable impurities, and reduce water uptake, thereby improving their overall characteristics. Hybridization of luffa NFC with other natural or synthetic fibers, e.g., glass, carbon, ceramic, flax, jute, etc., can enhance the properties of the end composite material. However, luffa fibers have exhibited a profuse compatibility with epoxy matrix.

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Investigation of the Sound Absorption and Transmission Loss Performances of Green Homogenous and Hybrid Luffa and Jute Fiber Samples

Applied Science and Engineering Progress ◽

10.14416/j.asep.2021.04.005 ◽

2021 ◽

Author(s):

Ahmet C. Ozcan ◽

Kenan Y. Sanliturk ◽

Garip Genc ◽

Hasan Koruk

Keyword(s):

High Frequency ◽

Sound Absorption ◽

Transmission Loss ◽

Natural Fibers ◽

Acoustic Properties ◽

Jute Fiber ◽

Transmission Losses ◽

Hybrid Fiber ◽

Practical Applications ◽

Impedance Tube Method

In order to promote the use of natural fibers in noise and vibration applications, the properties of these structures should be fully identified. The sound absorption coefficients (SACs) and transmission losses (TLs) of green luffa fiber samples are thoroughly investigated and their acoustic performances are compared with the acoustic performances of green homogenous jute and hybrid jute/luffa fiber samples in this study. For this purpose, green homogenous luffa and jute fiber samples and their green hybrid fiber samples with different thicknesses (10, 20, 30, and 40 mm) are produced and their SACs and TLs are determined using the impedance tube method. First, the methods for the experimental identification of acoustic properties are presented and the variations in the measured acoustic properties are identified. After that, the effects of sample thickness on the acoustic performances of homogenous luffa as well as jute samples and their hybrid fiber samples as a function of frequency are explored. The thickness-dependent tendencies of the SACs and TLs of homogenous and hybrid luffa and jute fiber samples for low, medium and high frequency ranges are determined. Then, the acoustic performances of the homogenous and hybrid luffa and jute samples are compared and evaluated. The results and analyses for the acoustic properties of homogeneous luffa and jute fiber samples and their hybrid fiber samples for a variety of thicknesses and different frequencies presented here can be used to design homogenous as well as hybrid luffa and jute fiber structures in practical applications.

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Investigation of the acoustic properties of needle punched nonwoven produced of blend with sustainable fibers

International Journal of Clothing Science and Technology ◽

10.1108/ijcst-01-2018-0012 ◽

2018 ◽

Vol 30 (3) ◽

pp. 444-458 ◽

Cited By ~ 3

Author(s):

Shariful Islam ◽

Shaikh Md. Mominul Alam

Keyword(s):

Absorption Coefficient ◽

Sound Absorption ◽

Transmission Loss ◽

Natural Fibers ◽

Sound Transmission ◽

Textile Composites ◽

Acoustic Properties ◽

Textile Composite ◽

Content Type ◽

Hemp Fibers

Purpose The purpose of this paper is to investigate the acoustic properties of needle-punched nonwovens produced of bamboo, banana and hemp fibers blended with polyester (PET) and polypropylene (PP) as they are supportive enough to minimize sound transmission inside the automobiles. Design/methodology/approach Textile materials like bamboo, banana and hemp blended with PET and PP in the ratio of 35:35:30 were applied to make the web. The needle-punching technique was applied to each web for three times to form a full nonwoven textile composite. The concept of PET/PP blend with natural fibers was to enhance the consistency and thermoform propensity of the composites. When nonwoven textile composites were placed in between a sound source and a receiver, they absorbed annoying sound by dissolving sound wave energy. Sound absorption coefficient was measured by the impedance tube method as per ASTM C384 Standard. Bamboo/PET/PP composite showed the highest absorption coefficient in most of the frequencies. Findings Physical and comfort properties were tested for the composites and it was noticed that bamboo/PET/PP composites with its compressed structure showed a better stiffness value, lesser thermal conductivity, lesser air permeability, better absorption coefficient and highest sound transmission loss compared to other two composites. At 840 Hz, the absorption coefficient of bamboo/PET/PP remained in satisfactory level but it was inferior by 20 percent in banana/PET/PP. Conversely at more frequencies like 1,680 Hz, there was a decrease from the target level in all the nonwovens composites, which could be enhanced by raising the thickness of the nonwovens, and all these properties of bamboo/PET/PP were considered appropriate for controlling noise inside the vehicles. Practical implications This research will provide facilities to decrease noise inside the vehicles. It will improve the apparent value of the automobiles to the traveler and also provide a sensible goodwill to the manufacturer. Originality/value This research will open several ways for the development of different nonwoven composites, particularly for the sound absorption and will open possible ways for the scholars to further study in this field.

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Investigation of sound transmission loss of natural fiber/rubber crumbs composite panels

Journal of Industrial Textiles ◽

10.1177/15280837211039574 ◽

2021 ◽

pp. 152808372110395

Author(s):

Magdi El Messiry ◽

Yasmin Ayman

Keyword(s):

Natural Fiber ◽

Transmission Loss ◽

Natural Fibers ◽

Sound Transmission ◽

Nonwoven Fabric ◽

Acoustic Properties ◽

Cotton Wool ◽

Sound Transmission Loss ◽

High Frequencies ◽

The World

Natural fibers and their waste are widely used all over the world, and their production has been increasing continuously. But, the rubber crumbs from used tire disposal are nonbiodegradable and present significant problems about their end-of-life given a critical environmental impact. These problems require recycling policies to provide the collection and recycling of used clothing, textile wastes, and rubber crumbs. In this work, the acoustic properties of insulator panels from the combination of textile fibers and rubber crumbs material were analyzed. Insulator panels demonstrated a good sound transmission loss (STL) characteristic, especially at high frequencies. The STL of the manufactured panels from a combination of fiber (cotton, wool, and Kapok) and rubber crumbs was investigated at the different sound frequencies. Results indicated that the fiber/rubber crumbs panel had a significant STL profile of 47 dB, 40 dB, and 35 dB, for Kapok, wool, and cotton, respectively. The addition of polylactic acid meltblown nonwoven fabric on the surface of the rubber crumbs side considerably increases the STL by 20%.

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