An Acoustic Reception Ability Analysis of SONAR Multilayer Structures by Using Elastic Theory

Hyun-Wung Kwon; Suk-Yoon*† Hong; Jee-Hun** Song; Sung-Hee* Kim; Jae-Jin*** Jeon; Young-Soo*** Seo

doi:10.7776/ASK.2013.32.4.301

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2013 Vol.32, Issue 4 Preview Page Next Page

An Acoustic Reception Ability Analysis of SONAR Multilayer Structures by Using Elastic Theory 탄성이론을 이용한 소나 다층구조물의 음향 수신 성능해석

31 July 2013. pp. 301-307

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Abstract

SONAR detection performance is one of the key survivability factors in underwater weapon systems. In order to catch the acoustic ability of SONAR, multilayer SONAR structures are analyzed using the elastic theory. The applied results for the simple models are compared with those from commercial program, ANSYS, and the reliable results are obtained. The analysis of sound pressure level (SPL) and echo reduction (ER) by the thickness change of multilayer SONAR structures are performed using the verified elastic theory. As the thickness of anechoic layer is increased, SPL is distributed evenly and ER is increased slightly with the frequency. In decoupling layers and steel layers, SPL are hardly changed and ER is slightly decreased with the thickness increase of those layers. SPL and ER are not affected by the thickness change of the carbon reinforced plastic (CRP) layer. Therefore, to improve the acoustic ability of multilayer SONAR structures, the thickness increase of the anechoic layer and minimization of the decoupling layer, steel layer and CRP layer are desirable.

Keywords

Multilayer structure

Elastic theory

Sound press level (SPL)

Echo redution (ER)

수중무기체계에 있어 소나 탐지 성능은 생존성 향상을 위한 중요한 인자이다. 소나의 음향수신 성능을 파악하기 위해서 탄성이론을 이용하여 소나 다층구조의 음향 성능을 해석하였다. 단순구조물에 대하여 탄성이론을 적용하여 얻은 본 해석 결과를 상용해석프로그램인 ANSYS와 비교하였고, 만족할만한 결과를 얻었다. 검증된 탄성이론을 이용하여 소나 다층구조의 층별 두께 변화에 따른 음압 및 반향음 감소 해석을 수행하였다. 무반향(anechoic)층의 두께가 증가할수록 주파수에 따른 음압이 고르게 분포하고 반향음 감소량이 약간 증가하는 것을 확인하였다. 비결합(decoupling)층과 스틸(steel)층의 경우 두께에 따른 음압의 변화는 거의 없으나 두꺼워질수록 반향음이 약간 감소하는 결과를 나타내었다. 탄소강화플라스틱(Carbon Reinforced Platic, CRP)층의 두께 변화는 음압과 반향음 감소량에 영향이 없는 것을 확인하였다. 따라서 소나 다층구조의 음향성능을 높이기 위해서는 무반향층을 두껍게 하고, 비결합층, 스틸층과 탄소강화플라스틱층은 최소화하는 것이 바람직할 것으로 예상된다.

키워드

다층구조

탄성이론

음압해석

반향음 감소

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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 : 32
No :4
Pages :301-307
Received Date : 2013-03-21
Revised Date : 2013-05-16
Accepted Date : 2013-06-26
DOI :https://doi.org/10.7776/ASK.2013.32.4.301

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

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