A study on the acoustic performance of a silencer according to the change of properties of absorbing material

Yongbeom Lee; Haesang Yang

doi:10.7776/ASK.2021.40.4.278

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2021 Vol.40, Issue 4 Preview Page Next Page

Research Article

A study on the acoustic performance of a silencer according to the change of properties of absorbing material 흡음재 물성치 변화에 따른 소음기 음향성능 연구

31 July 2021. pp. 278-289

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Abstract

In this study, the acoustic performance of a dissipative silencer used in the ship with excellent performance compared to its size was predicted and analyzed using a numerical analysis method to reduce the pipe noise. To this end, the performance of the single expansion chamber-shaped silencer was verified using experimental and numerical analysis methods. The acoustic performance of the silencer was expressed using the Transmission Loss (TL), an indicator of its own performance, and the result was derived using the two-load method, which measured by changing the impedance at the end of the pipe. For the numerical analysis method, a general-purpose finite element analysis program was used, and the Delany-Bazley-Miki model with the flow resistivity of the sound absorbing material as an input parameter was applied. Finally, we compared the experimental and simulated results for each of the acoustic performances of the single expansion type and the dissipative silencer to confirm the consistency of the results, and predicted and analyzed the simulation results for four cases according to the properties of the sound absorbing material.

Keywords

Sound absorbing material

Delany-Bazley-Miki model

Two-load method

Acoustic performance

본 연구에서는 함정에서 발생하는 배관소음을 줄이기 위해 크기 대비 성능이 우수한 흡음형 소음기의 음향성능을 수치해석 방법을 이용하여 예측 및 분석하였다. 이를 위해 단일확장형 소음기의 음향성능을 실험 및 수치해석 방법을 이용하여 검증하였다. 음향성능은 자체 성능을 나타내는 지표인 투과손실을 이용하여 나타내었고, 실험은 배관 끝단 임피던스를 바꿔서 측정하는 two-load method를 통해 결과를 도출하였다. 수치해석은 범용 유한요소해석 프로그램을 사용하여 실시하였고, 흡음재 유동저항을 입력 매개변수로 하는 Delany-Bazley-Miki 모델을 적용하였다. 최종적으로, 단순확장형 및 흡음형 소음기 음향성능 각각에 대한 실험·모의 결과를 비교하여 결과의 일치성을 확인하였으며, 흡음재 물성치에 따라 4가지 경우로 분류하여 각각에 대한 시뮬레이션 결과를 예측 및 분석하였다.

키워드

흡음재

Delany-Bazley-Miki 모델

Two-load method

음향성능

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 : 40
No :4
Pages :278-289
Received Date : 2021-05-03
Revised Date : 2021-06-18
Accepted Date : 2021-06-29
DOI :https://doi.org/10.7776/ASK.2021.40.4.278

The Journal of the Acoustical Society of Korea ISSN:1225-4428(Print) 2287-3775(Online) 한국음향학회지

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