Calculating transmission loss of cylindrical silencers lined with multi-layered poroelastic sound absorbing materials using mode matching method

Jongmoo Lee; Haesang Yang; Woojae Seong

doi:10.7776/ASK.2022.41.4.375

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2022 Vol.41, Issue 4 Next Page

Research Article

Calculating transmission loss of cylindrical silencers lined with multi-layered poroelastic sound absorbing materials using mode matching method 모드 매칭법을 이용한 다층 다공성 탄성 흠음재가 채워진 원통형 소음기의 음향투과손실 계산

31 July 2022. pp. 375-388

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Abstract

This paper deals with the process of obtaining sound transmission loss of a cylindrical silencer lined with multi-layered poroelastic sound absorbing materials. The Biot model and the Johnson-Champoux-Allard- Lafarge (JCAL) model were used to deal with waves propagating in multi-layered poroelastic materials. The boundary conditions required for analysis of the silencer were obtained and the numerical process of finding modes was explained. A numerical experiment was conducted on the 2-layered silencer using the modes and the transmission loss converged with the first 12 modes. Finally, the mode matching method proposed in this research was validated by being compared with the results calculated from Finite Element Method (FEM) about different kinds of sound absorbing materials.

Keywords

Porous material

Silencer

Biot theory

Johnson-Champoux-Allard-Lafarge (JCAL)

Transmission loss

Mode matching

본 논문은 다층 다공성 흡음재가 채워진 원통형 소음기의 음향투과손실을 구하는 과정을 다루었다. 다층 다공성 흡음재 내부에서 전파되는 파동을 다루기 위해 Biot모델과 Johnson-Champoux-Allard-Lafarge(JCAL) 모델을 이용했다. 소음기 해석에 필요한 경계조건들을 얻었고 그것들을 토대로 수치적으로 모드를 구하는 과정을 설명했다. 얻은 모드들을 이용하여 2층 소음기에 대해 수치적인 실험을 진행했으며 처음 12개의 모드만으로도 음향투과손실이 수렴함을 보였다. 마지막으로 흡음재의 종류를 바꿔가면서 음향투과손실을 계산했고 이를 유한요소법을 이용한 결과와 비교함으로써 본 연구에서 제시한 모드 매칭법의 유효성을 검증했다.

키워드

다공성 물질

소음기

비오 이론

Johnson-Champoux-Allard-Lafarge (JCAL)

투과손실

모드 매칭

References

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Information

Publisher :The Acoustical Society of Korea
Publisher(Ko) :한국음향학회
Journal Title :The Journal of the Acoustical Society of Korea
Journal Title(Ko) :한국음향학회지
Volume : 41
No :4
Pages :375-388
Received Date : 2022-04-11
Accepted Date : 2022-06-22
DOI :https://doi.org/10.7776/ASK.2022.41.4.375

The Journal of the Acoustical Society of KoreaISSN:1225-4428(Print) 2287-3775(Online)한국음향학회

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