scholarly journals Fabrication of Millable Polyurethane Elastomer/Eucommia Ulmoides Rubber Composites with Superior Sound Absorption Performance

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7487
Author(s):  
Yuhang Dong ◽  
Dexian Yin ◽  
Linhui Deng ◽  
Renwei Cao ◽  
Shikai Hu ◽  
...  
Keyword(s):  
Sound Absorption ◽  
Polyurethane Elastomer ◽  
Eucommia Ulmoides ◽  
Frequency Range ◽  
Rubber Composites ◽  
Absorption Properties ◽  
Absorbing Materials ◽  
Absorption Performance ◽  
Blending Process ◽  
Physical Blending

Sound absorbing materials combining millable polyurethane elastomer (MPU) and eucommia ulmoides rubber (EUG) were successfully fabricated via a physical blending process of EUG and MPU. The microstructure, crystallization performances, damping, mechanical and sound absorption properties of the prepared MPU/EUG composites were investigated systematically. The microstructure surface of various MPU/EUG composites became rough and cracked by the gradual incorporation of EUG, resulting in a deteriorated compatibility between EUG and MPU. With the increase of EUG content, the storage modulus (E’) of various MPU/EUG composites increased in a temperature range of −50 °C to 40 °C and their loss factor (tanδ) decreased significantly, including a reduction of the tanδ of MPU/EUG (70/30) composites from 0.79 to 0.64. Specifically, the addition of EUG sharply improved the sound absorption performances of various MPU/EUG composites in a frequency range of 4.5 kHz–8 kHz. Compared with that of pure MPU, the sound absorption coefficient of the MPU/EUG (70/30) composite increased 52.2% at a pressure of 0.1 MPa and 16.8% at a pressure of 4 MPa, indicating its outstanding sound absorption properties.

scholarly journals Acoustic Panels Made of Paper Sludge and Clay Composites

2021 ◽  
Vol 13 (2) ◽  
pp. 637
Author(s):  
Tomas Astrauskas ◽  
Tomas Januševičius ◽  
Raimondas Grubliauskas
Keyword(s):  
Absorption Coefficient ◽  
Sound Absorption ◽  
Composite Panel ◽  
Sound Absorption Coefficient ◽  
Core Material ◽  
Paper Sludge ◽  
Frequency Range ◽  
Absorption Properties ◽  
Air Gaps ◽  
The Core

Studies on recycled materials emerged during recent years. This paper investigates samples’ sound absorption properties for panels fabricated of a mixture of paper sludge (PS) and clay mixture. PS was the core material. The sound absorption was measured. We also consider the influence of an air gap between panels and rigid backing. Different air gaps (50, 100, 150, 200 mm) simulate existing acoustic panel systems. Finally, the PS and clay composite panel sound absorption coefficients are compared to those for a typical commercial absorptive ceiling panel. The average sound absorption coefficient of PS-clay composite panels (αavg. in the frequency range from 250 to 1600 Hz) was up to 0.55. The resulting average sound absorption coefficient of panels made of recycled (but unfinished) materials is even somewhat higher than for the finished commercial (finished) acoustic panel (αavg. = 0.51).

scholarly journals Diffuse Sound Absorptive Properties of Parallel-Arranged Perforated Plates with Extended Tubes and Porous Materials

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1091 ◽  
Author(s):  
Dengke Li ◽  
Daoqing Chang ◽  
Bilong Liu
Keyword(s):  
Boundary Condition ◽  
Porous Material ◽  
Porous Materials ◽  
Sound Absorption ◽  
Azimuthal Angle ◽  
Octave Band ◽  
Frequency Range ◽  
Absorption Coefficients ◽  
Perforated Plates ◽  
Absorption Performance

The diffuse sound absorption was investigated theoretically and experimentally for a periodically arranged sound absorber composed of perforated plates with extended tubes (PPETs) and porous materials. The calculation formulae related to the boundary condition are derived for the periodic absorbers, and then the equations are solved numerically. The influences of the incidence and azimuthal angle, and the period of absorber arrangement are investigated on the sound absorption. The sound-absorption coefficients are tested in a standard reverberation room for a periodic absorber composed of units of three parallel-arranged PPETs and porous material. The measured 1/3-octave band sound-absorption coefficients agree well with the theoretical prediction. Both theoretical and measured results suggest that the periodic PPET absorbers have good sound-absorption performance in the low- to mid-frequency range in diffuse field.

Method of Testing of Sound Absorption Properties of Materials Intended for Ultrasonic Noise Protection

2013 ◽  
Vol 38 (2) ◽  
pp. 191-195 ◽  
Author(s):  
Dariusz Pleban
Keyword(s):  
Sound Absorption ◽  
Free Field ◽  
Tone Burst ◽  
Mineral Wool ◽  
Frequency Range ◽  
Absorption Properties ◽  
Open Cell Foam ◽  
Properties Of Materials ◽  
Cell Foam

Abstract Efficient ultrasonic noise reduction by using enclosures requires the knowledge of absorbing properties of materials in the frequency range above 4 kHz. However, standardized methods enable determination of absorption coefficients of materials in the frequency range up to 4 kHz. For this reason, it is proposed to carry out measurements of the sound absorption properties of materials in the free field by means of a tone-burst technique in the frequency range from 4 kHz to 40 kHz at angles of incidence varying from 0° to 60°. The absorption coefficient of a material is calculated from the reflection coefficient obtained by reflecting a tone-burst from both a perfectly reflecting panel and a combination of this panel and the sample of the tested material. The tests results show that mineral wool and polyurethane open-cell foam possess very good absorbing properties in this frequency range.

scholarly journals Sound Absorption Properties of Aluminum Sponges Manufactured by Infiltration Process

2010 ◽  
Vol 146-147 ◽  
pp. 1651-1654 ◽  
Author(s):  
Patricia M. Fernández ◽  
Luis J.R. Cruz ◽  
Luis E. García Cambronero ◽  
Cesar Díaz ◽  
María Ángeles Navacerrada
Keyword(s):  
Pore Size ◽  
Sound Absorption ◽  
Frequency Range ◽  
Absorption Factor ◽  
Absorption Properties ◽  
Infiltration Process ◽  
Interconnected Porosity ◽  
Factor Α

In this paper, the sound absorption properties of aluminum sponges manufactured by infiltration process have been studied. The results show that the sound absorption factor α changes in function of pore size. Additionally, the sound absorption factor α was sensitive to the frequency range measured and it was depending of the thickness sample. It was found that the interconnected porosity plays an important role increasing the sound absorption properties of the aluminum sponges studied.

Analysis of Sound Absorption Properties of Three-Leaf Microperforated Panel Absorbers without a Rigid Backing

2014 ◽  
Vol 937 ◽  
pp. 465-471
Author(s):  
Xiao Ling Gai ◽  
Xian Hui Li ◽  
Rui Wu ◽  
Bin Zhang ◽  
Jun Juan Zhao
Keyword(s):  
Sound Absorption ◽  
Low Frequency ◽  
Wide Frequency Range ◽  
Structure Design ◽  
Frequency Region ◽  
Theoretical Development ◽  
Frequency Range ◽  
Absorption Properties ◽  
High Frequency Region ◽  
Energy Dissipated

Microperforated panel (MPP) absorbers have been developed rapidly and used in many fields in recent years. First, based on the Maa’s theory, the theoretical development of MPP is reviewed in this paper. Furthermore, structure design and processing technology of MPP are introduced. Finally, the further development of MPP is discussed. Based on the MPP theory and electro-acoustical equivalent circuit principle, sound absorption properties of three-leaf microperforated panel (TMPP) absorbers without a rigid backing are studied to broaden the sound absorption bandwidth of MPP structure. Simulation results show that TMPP absorbers without a rigid backing have two resonance peaks and the energy dissipated coefficient remains constant in the low frequency range. The resonance frequency moves toward low frequency region with the increasing of the distance, thickness and pore diameter of MPP and moves toward high frequency region with the increasing of the perforation when other parameters keep invariant. The energy dissipated coefficient more than 0.5 over 8 octaves by choosing proper parameters. In conclusion, TMPP absorbers without a rigid backing have good sound absorption properties in a wide frequency range.

scholarly journals Sound Absorption Properties of Materials Based on Recycled Plastic Granule Mixtures

2021 ◽  
Vol 29 (1) ◽  
pp. 15-19
Author(s):  
Andrea Biskupičová ◽  
Miriam Ledererová ◽  
Stanislav Unčík ◽  
Christ Glorieux ◽  
Monika Rychtáriková
Keyword(s):  
Absorption Spectrum ◽  
Absorption Coefficient ◽  
Sound Absorption ◽  
Ethylene Vinyl Acetate ◽  
Frequency Range ◽  
Absorption Properties ◽  
Audible Frequency ◽  
Properties Of Materials ◽  
Two Peaks ◽  
Foam Plastics

Abstract This article reports on impedance tube measurements of the sound absorption coefficient α (-) of selected recycled foam plastics, i.e., ethylene-vinyl acetate (EVA), polyvinyl chloride (PVC), polystyrene (PS), and polypropylene (PP), in different mixtures with a binding adhesive. The effect of the thickness of the sample on the sound absorption spectrum as well as the variability in absorption across the different samples of the same composition and thickness are discussed. For the EVA/ PP and PS/PP mixtures, the spectrum is characterized by two peaks that shift as the thickness is changing. These mixtures were also found to be the most absorbent across the whole audible frequency range.

scholarly journals Effect of the Pore Shape and Size of 3D-Printed Open-Porous ABS Materials on Sound Absorption Performance

Materials ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 4474
Author(s):  
Katarina Monkova ◽  
Martin Vasina ◽  
Peter Pavol Monka ◽  
Drazan Kozak ◽  
Jan Vanca
Keyword(s):  
Sound Absorption ◽  
Negative Impact ◽  
Excitation Frequency ◽  
Volume Ratio ◽  
Acrylonitrile Butadiene Styrene ◽  
Normal Incidence ◽  
Absorption Properties ◽  
Absorption Performance ◽  
3D Printed ◽  
Material Volume

Noise has a negative impact on our environment and human health. For this reason, it is necessary to eliminate excessive noise levels. This paper is focused on the study of the sound absorption properties of materials with open-porous structures, which were made of acrylonitrile butadiene styrene (ABS) material using additive technology. Four types of structures (Cartesian, Octagonal, Rhomboid, and Starlit) were evaluated in this work, and every structure was prepared in three different volume ratios of the porosity and three different thicknesses. The sound absorption properties of the investigated ABS specimens were examined utilizing the normal incidence sound absorption and noise reduction coefficients, which were experimentally determined by the transfer function method using a two-microphone acoustic impedance tube. This work deals with various factors that influence the sound absorption performance of four different types of investigated ABS material’s structures. It was found, in this study, that the sound absorption performance of the investigated ABS specimens is strongly affected by different factors, specifically by the structure geometry, material volume ratio, excitation frequency of an acoustic wave, material’s thickness, and air space size behind the tested sound-absorbing materials.

scholarly journals Numerical Simulation for the Sound Absorption Properties of Ceramic Resonators

Fibers ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 77
Author(s):  
Giuseppe Ciaburro ◽  
Gino Iannace
Keyword(s):  
Neural Networks ◽  
Artificial Neural Networks ◽  
Simulation Model ◽  
Sound Absorption ◽  
Ceramic Materials ◽  
Acoustic Behavior ◽  
Absorption Properties ◽  
Acoustic Resonators ◽  
Absorption Performance ◽  
Artificial Neural

This work reports the results of experimental measurements of the sound absorption coefficient of ceramic materials using the principle of acoustic resonators. Subsequently, the values obtained from the measurements were used to train a simulation model of the acoustic behavior of the analyzed material based on artificial neural networks. The possible applications of sound-absorbing materials made with ceramic can derive from aesthetic or architectural needs or from functional needs, as ceramic is a fireproof material resistant to high temperatures. The results returned by the simulation model based on the artificial neural networks algorithm are particularly significant. This result suggests the adoption of this technology to find the finest possible configuration that allows the best sound absorption performance of the material.

Sound absorption property of PVA/PEO/GO nanofiber membrane and non-woven composite material

2019 ◽  
Vol 50 (4) ◽  
pp. 512-525
Author(s):  
Huan Liu ◽  
Baoqi Zuo
Keyword(s):  
Graphene Oxide ◽  
Polyvinyl Alcohol ◽  
Polyethylene Oxide ◽  
Sound Absorption ◽  
Woven Fabric ◽  
Nanofiber Membrane ◽  
Absorption Properties ◽  
Blend Films ◽  
Absorption Performance ◽  
Nanofiber Membranes

Blend films based on polyvinyl alcohol/polyethylene oxide (70/30 wt%) undoped and doped with different concentration of graphene oxide were prepared by spiral vane electrospinning. Characteristic properties of the blend films were investigated by using X-ray diffraction and scanning electron microscopy. The sound absorption performance of the compositions (nanofiber membranes and needle punched non-woven fabric) was tested by an impedance tube. The sound absorption performance of non-woven fabric has greatly improved after combining with thin nanofiber membranes. With addition of graphene oxide, the fibers were intertwined in a loop and form a network, the areal density and surface roughness of the nanofiber membrane are reduced. Composites containing polyvinyl alcohol/polyethylene oxide nanofiber membranes and composites containing polyvinyl alcohol/polyethylene oxide/graphene oxide nanofiber membranes exhibited different sound absorption properties in different frequency bands. When the fiber coefficient of variation was small, the average sound absorption coefficient of the composite material was high. However, composites containing both polyvinyl alcohol/polyethylene oxide and polyvinyl alcohol/polyethylene oxide/graphene oxide nanofiber membranes had similar sound absorption properties, and the average sound absorption coefficient was greater than that of polyvinyl alcohol/polyethylene oxide composites.

Sign in / Sign up

Export Citation Format

Share Document