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

Textiles ◽  
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.

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

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.

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

2013 ◽  
Vol 8 (4) ◽  
pp. 155892501300800 ◽  
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.

Empirical study on the correlation between measurement methods under diffuse and direct sound field conditions for determining sound absorption and airborne sound insulation properties of noise barriers

2021 ◽  
Vol 263 (3) ◽  
pp. 3350-3361
Author(s):  
Andreas Fuchs ◽  
Reinhard Wehr ◽  
Marco Conter
Keyword(s):  
Empirical Study ◽  
Sound Absorption ◽  
Sound Field ◽  
Research Programme ◽  
Measurement Methods ◽  
Field Conditions ◽  
Acoustic Properties ◽  
Sound Insulation ◽  
Noise Barriers ◽  
Airborne Sound

In the frame of the SOPRANOISE project (funded by CEDR in the Transnational Road Research Programme 2018) the database of the European noise barrier market developed during the QUIESST project was updated with newly acquired data. This database gives the opportunity for an empirical study on the correlation between the different measurement methods for the acoustic properties of noise barriers (according to the EN 1793 series) to further investigate the interrelationships between these methods by using single-number ratings and third-octave band data. First a correlation of the measurement methods for sound absorption under diffuse field conditions (EN 1793-1) and sound reflection under direct sound field conditions (EN 1793-5) is presented. Secondly, a correlation of the measurement methods for airborne sound insulation under diffuse field conditions (EN 1793-2) and airborne sound insulation under direct sound field conditions (EN 1793-6) is shown. While for airborne sound insulation a distinct correlation is found due to the wide data range, for sound absorption no robust correlation can be found.

Tensile Properties of Epoxy Matrix Reinforced with Fique Fabric

2020 ◽  
Vol 1012 ◽  
pp. 14-19
Author(s):  
Michelle Souza Oliveira ◽  
Fabio da Costa Garcia Filho ◽  
Fernanda Santos da Luz ◽  
Artur Camposo Pereira ◽  
Luana Cristyne da Cruz Demosthenes ◽  
...  
Keyword(s):  
Mechanical Strength ◽  
Polymer Composites ◽  
Natural Fiber ◽  
Volume Fraction ◽  
Fiber Reinforced Polymer ◽  
Epoxy Composites ◽  
Synthetic Fiber ◽  
Fiber Reinforced ◽  
Reinforced Polymer ◽  
Fiber Reinforced Polymer Composites

Composite materials are being extensively studied for ballistic armor. Their main advantage is connected to the possibility of deeply reducing weight and costs by maintaining high performances in terms of strength and security. Epoxy composites are reinforced with natural fibers which are replacing other synthetic reinforcement materials. Composites are prepared using polymers as matrix material because of ease of production with different reinforcements. The mechanical strength of the natural fiber reinforced polymer composites has been compared with synthetic fiber reinforced polymer composites and it is found that for achieving equivalent mechanical strength of the material, the volume fraction of the natural fiber should be much higher than synthetic fiber. This work being an experimental study on untreated “as received” fique fabric-reinforced epoxy composites, to demonstrate the potential of this renewable source of natural fiber for use in a number of applications.

Effect of Natural and Synthetic Fibers and Film and Moisture Content on Stratum Corneum Hydration in an Occlusive System

1997 ◽  
Vol 67 (8) ◽  
pp. 585-592 ◽  
Author(s):  
Bruce A. Cameron ◽  
Donna M. Brown ◽  
Merry Jo Dallas ◽  
Brenda Brandt
Keyword(s):  
Moisture Content ◽  
Stratum Corneum ◽  
Natural Fiber ◽  
Fiber Type ◽  
Normal Skin ◽  
Synthetic Fiber ◽  
Hydration Level ◽  
Synthetic Fibers ◽  
Significant Difference ◽  
Natural And Synthetic

The effects of fabric made from natural and synthetic fibers and film on transepidermal water loss (tewl) from the stratum corneum (sc) were investigated using an occluded system. Sixteen fabrics differing in fiber type and construction were placed on the volar forearm of 35 female subjects in a dry state (standard moisture regain) and a wetted state. Each fabric was in place for 40 minutes before tewl was measured. There was no statistically significant difference in tewl measurements on a control skin site from the beginning to the end of the 75-minute test session in a controlled conditioned environment. Placement of dry fabrics on the skin did not significantly affect the hydration level of the sc, though all dry fabrics did increase the hydration level slightly. Wetted wool and cotton fabrics significantly hydrated the sc when levels were compared to either normal skin or skin covered by dry fabrics. Of the seven synthetic fiber fabrics tested in a wetted state, three (acrylic, ptfe, and spun nylon) significantly increased the sc hydration level. These three fabrics and the natural fiber fabrics had comparable wetted moisture content.

scholarly journals Influence of polymer fibers on rheological properties of cement mortars

2017 ◽  
Vol 7 (1) ◽  
pp. 228-236 ◽  
Author(s):  
Dorota Malaszkiewicz
Keyword(s):  
Rheological Properties ◽  
Volume Fraction ◽  
Fiber Type ◽  
Cementitious Materials ◽  
Plastic Viscosity ◽  
Synthetic Fiber ◽  
Rheological Parameters ◽  
Model Parameters ◽  
Fine Aggregate ◽  
Bingham Model

AbstractThe reinforcing effect of fibers in cement composites often results in the improvement of the brittle nature of cementitious materials. But the decrease in the workability of fresh concrete is often the disadvantage of fibers addition. Conventional single-point workability tests cannot characterize workability of concrete in terms of fundamental rheological parameters. To this end, this paper describes an investigation of the influence of synthetic fiber additions (fiber length in the range 12–50 mm and volume fraction in the range 0–4%) on the rheological properties of fiber reinforced fresh mortar (FRFM) and development of these properties over time. The rheometer Viskomat XL was used in this study. Within the limitations of the instrument and testing procedure it is shown that FRFMs conform to the Bingham model. Natural postglacial sand 0/4 mm was used as a fine aggregate and cement CEMI 42.5 R was used as a binder. Three commercial synthetic fibers were selected for these examinations. Rheological properties were expressed in terms of Bingham model parameters g (yield value ) and h (plastic viscosity). Based on the test results it was found out that the fiber type and volume fraction affected both the yield stress and plastic viscosity.

scholarly journals Experimental Study on the Sound Absorption Properties of Finger Millet Straw, Darbha, and Ripe Bulrush Fibers

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
K. M. Rakesh ◽  
Ramachandracharya Srinidhi ◽  
S. Gokulkumar ◽  
K. S. Nithin ◽  
S. Madhavarao ◽  
...  
Keyword(s):  
Absorption Coefficient ◽  
Sound Absorption ◽  
Finger Millet ◽  
Natural Fiber ◽  
Fiber Type ◽  
Natural Fibers ◽  
Noise Pollution ◽  
Sound Absorption Coefficient ◽  
Human Beings ◽  
Fiber Arrangement

Nowadays, emerging noise pollution by external factors causes harmful diseases in human beings. The development of a bio-based filler or panel will help to eliminate some unwanted noise in working places and living rooms. This work aimed to develop an ecowaste fiber (leftover after harvesting)-based sound absorber and analyze its capabilities for sound absorption. The ecowaste fibers are collected by the gleaning process, i.e., the process of collecting leftovers from fields. The sound absorption capabilities of three natural fibers extracted from Eleusine coracana (Finger millet) straw, Desmostachya bipinnata (Darbha), and Typha domingensis (Ripe bulrush) plants are investigated in this study, both individually and in hybrid combinations. The sound absorption property mainly depends on factors such as porosity, flow resistivity, thickness, density, and tortuosity. Fiber length and fiber type play a significant role when fibers are arranged individually or in hybrid combinations. The stacking effect on the sound absorption coefficient of hybridized fiber arrangement was experimentally analyzed. The sound absorption coefficient (α) was found to be lower in the range of 1000 Hz–2500 Hz for all the combinations. As a homogenous fiber arrangement, the darbha fiber exhibited the better NRC (noise reduction coefficient) of 0.86 for 50 mm thickness among three different fibers and as a hybrid composition, ripe bulrush and darbha fibers exhibited NRC of 0.90 which is more capable of absorbing sound in the critical frequency range of 500 to 2000 Hz. These types of natural fiber fillers are highly capable of better sound absorbing and used in the applications such as classrooms, sound recording rooms, and theatres.

scholarly journals The Effect of Alkali Treatment And Microcrystalline Cellulose Addition on Density Value of Cantala Fiber Reinforced Unsaturated Polyester Composites

2021 ◽  
Vol 20 (1) ◽  
pp. 1
Author(s):  
Muhammad Ghozali ◽  
Dody Ariawan ◽  
Eko Surojo
Keyword(s):  
Microcrystalline Cellulose ◽  
Natural Fiber ◽  
Volume Fraction ◽  
Treatment Time ◽  
Alkali Treatment ◽  
Unsaturated Polyester ◽  
Reinforced Composites ◽  
Fiber Reinforced ◽  
Molding Method ◽  
Polyester Composites

<p>Natural fiber reinforced composites is one materials potentially developing in Indonesia. One of biggest problem with composites specimen is its void. One properties to find out void of composites is composites density value. The objective of research is to investigate the effect of fiber alkali (NaOH) treatment and microcrystalline cellulose (MCC) addition on density value of cantala fiber reinforced unsaturated polyester composites. Firstly, cantala fibers was submerged into alkali (NaOH) 6% solution for 0, 3, 6, 9, and 12 hours. Furthermore, the fiber was washed using acetid acid and then using clean water to reach pH 7. Thereafter, cantala fiber was dried in the oven for 10 hours at temperature 60<sup>0</sup>C. Composites was composed of cantala fiber, unsaturated polyester polymer matrix, and microcrystalline cellulose according to the composition with volume fraction 30%. Composites was casted using compression molding method with compressive strength of 10 MPa for 12 hours. All specimens of composites undertake post cure for 2 hours at 60<sup>0</sup>C. Density test was conducted using densimeter by calculating the density of composites in the air and the water. The result of research showed that the longer the alkali treatment time and the more addition of microcrystalline cellulose (MCC) filler, the higher is the composites density. The higher density value of cantala fiber reinforced unsaturated polyester is alkali treatment 6 hours, which was 1.223 gr/cm<sup>3</sup>.</p>

scholarly journals Acoustic Properties of 316L Stainless Steel Lattice Structures Fabricated via Selective Laser Melting

Metals ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 111 ◽  
Author(s):  
Xiaojing Sun ◽  
Fengchun Jiang ◽  
Jiandong Wang
Keyword(s):  
Stainless Steel ◽  
Selective Laser Melting ◽  
Process Parameters ◽  
Sound Absorption ◽  
316L Stainless Steel ◽  
Acoustic Properties ◽  
Sound Insulation ◽  
Frequency Range ◽  
Laser Melting ◽  
The Difference

A bulk specimen and two different lattice sandwich structures composed of 316L stainless steel were fabricated via selective laser melting. This study analysed the acoustic properties, including sound insulation and sound absorption, of the three kinds of structures, which were produced via selective laser melting under the same process parameters. The results showed that the difference in the unit structures, rather than microstructural difference, was the main reason for the difference in acoustic properties between the samples. Under the same process parameters, the microstructure of the different structures had the same cell structure. However, the sound absorption properties of the lattice sandwich structures were better than those of the bulk sample in the measured frequency range of 1–6.3 kHz. The lattice sandwich structure with 2.5 × 2.5 × 2.5 mm3 unit structures exhibited excellent sound insulation properties in the frequency range of 1–5 kHz.

scholarly journals Mechanical Performance and Moisture Absorption of Unidirectional Bamboo Fiber Polyester Composite

2018 ◽  
Vol 911 ◽  
pp. 88-94 ◽  
Author(s):  
Omid Nabinejad ◽  
Sujan Debnath ◽  
Jack Kai Beh ◽  
Mohammad Yeakub Ali
Keyword(s):  
Mechanical Properties ◽  
Moisture Absorption ◽  
Mechanical Performance ◽  
Natural Fiber ◽  
Alkali Treatment ◽  
Bamboo Fiber ◽  
Synthetic Fiber ◽  
Moisture Uptake ◽  
Polyester Composite ◽  
Bamboo Fibers

Bamboo fibers as a natural fiber offer numerous advantages such as high specific strength over synthetic fiber when used as reinforcing fiber for polymer composites. Yet the hydrophilic nature of bamboo fibers with high moisture absorption results in incompatibility in between bamboo fibers and unsaturated polyester resin. An experimental study was carried out to investigate the effects of alkali treatment of bamboo fiber on the mechanical properties and water sorption properties of polyester composite. The result revealed that, the bamboo fiber polyester composite with 5% Alkali treated bamboo fiber possesses the highest mechanical properties. Besides, Alkali treated fibers composite showed a significant reduction in moisture uptake compared to untreated fibers, where composite with 7% Alkali treated showed the lowest moisture uptake.

Sign in / Sign up

Export Citation Format

Share Document