Enhancing of broadband sound absorption through soft matter

2021 ◽  
Author(s):  
Fuyin Ma ◽  
Chang Wang ◽  
Yang Du ◽  
Zicai Zhu ◽  
Jiu Hui Wu

This paper proposed a metamaterial design method that uses soft matter for constructing a unique soft acoustic boundary to effectively improve broadband sound absorption performance. Specifically, attaching a flexible polyvinyl...

Author(s):  
Qingxuan Liang ◽  
Yutao Wu ◽  
Peiyao Lv ◽  
Jin He ◽  
Fuyin Ma ◽  
...  

2021 ◽  
pp. 004051752110155
Author(s):  
Min Peng ◽  
Xiaoming Zhao ◽  
Weibin Li

Perforated materials in the traditional sense are rigid, usually dense, costly and inflexible. For this study, polyester/cotton blended woven fabric as the base fabric, nano-SiO2 (silicon dioxide) as the functional particles and PU (polyurethane) as the matrix were selected. Accordingly, flexible PU/SiO2 perforated coating composites with different process parameters were developed. The influence of the nano-SiO2 content, perforation diameter, perforation rate, number of fiber felt layers and cavity depth on the sound absorption coefficient were investigated. The resonant frequencies of materials with different cavity depths were evaluated by both theoretical calculation and experimental method. It was found that the flexible perforated composite has good sound absorption and mechanical properties, and has great potential for applications requiring soft and lightweight sound absorption materials.


Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1091 ◽  
Author(s):  
Dengke Li ◽  
Daoqing Chang ◽  
Bilong Liu

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.


2019 ◽  
Vol 146 ◽  
pp. 134-144 ◽  
Author(s):  
F. Bucciarelli ◽  
G.P. Malfense Fierro ◽  
M. Meo

2021 ◽  
Author(s):  
Kimihiro Sakagami ◽  
Midori Kusaka ◽  
Takeshi Okuzono ◽  
Shigeyuki Kido ◽  
Daichi Yamaguchi

There are various measures currently in place to prevent the spread of COVID-19; however, in some cases, these can have an adverse effect on the acoustic environment in buildings. For example, transparent acrylic partitions are often used in eating establishments, meeting rooms, offices, etc., to prevent droplet infection. However, acrylic partitions are acoustically reflective; therefore, reflected sounds may cause acoustic problems such as difficulties in conversation or the leakage of conversation. In this study, we performed a prototyping of transparent acrylic partitions to which a microperforated panel (MPP) was applied for sound absorption while maintaining transparency. The proposed partition is a triple-leaf acrylic partition with a single acrylic sheet without holes between two MPP sheets, as including a hole-free panel is important to a possible droplet penetration. The sound absorption characteristics were investigated by measuring the sound absorption in a reverberation room. As the original prototype showed sound absorption characteristics with a gentle peak and low values due to the openings on the periphery, it was modified by closing the openings of the top and sides. The sound absorption performance was improved to some extent when the top and sides were closed, although there remains the possibility of further improvement. This time, only the sound absorption characteristics were examined in the prototype experiments. The effects during actual use will be the subject of future study.


2016 ◽  
Vol 50 (1) ◽  
pp. 015301 ◽  
Author(s):  
Jieun Yang ◽  
Joong Seok Lee ◽  
Yoon Young Kim

Sign in / Sign up

Export Citation Format

Share Document