DOI QR코드

DOI QR Code

An experimental analysis of vibration-induced noise isolation characteristics of a sonar acoustic sensor

소나 음향센서의 진동유기 소음 차단 특성에 대한 실험적 연구

  • 김경섭 (국방과학연구소 제6기술연구본부) ;
  • 제엽 (국방과학연구소 제6기술연구본부) ;
  • 김호준 (국방과학연구소 제6기술연구본부) ;
  • 조요한 (국방과학연구소 제6기술연구본부) ;
  • 이정민 (국방과학연구소 제6기술연구본부) ;
  • 김동현 (LIG넥스원(주) 해양2연구소) ;
  • 장우석 (LIG넥스원(주) 해양2연구소)
  • Received : 2018.11.08
  • Accepted : 2019.03.27
  • Published : 2019.03.31

Abstract

In this paper, the results of underwater vibration experiment are analyzed to verify platform vibration-induced noise isolation characteristics of a hull-mounted acoustic sensor. The experimental condition causing platform vibration-induced noise is generated using the mock-up hull, where the acoustic sensor is installed, with shaker in an acoustic water tank. The performance indices of ATF (Acceleration Transfer Function), AVS (Acceleration Voltage Sensitivity), and IL (Insertion Loss) for the acoustic sensor are calculated from the output of the standard accelerometers, which are installed on the mock-up hull and the acoustic sensor, and the output signal of the acoustic sensor. The frequency-dependent noise isolation characteristics of the acoustic sensor are analyzed based on the calculated performance indices and an effectiveness of the experiment is examined.

본 논문에서는 선체부착형 음향센서의 플랫폼 진동유기 소음 차단 특성을 확인하기 위한 수중 진동 실험을 수행하고 결과를 분석하였다. 음향수조 환경에서 음향센서가 설치된 선체모사구조물과 가진기를 이용하여 플랫폼 진동유기 소음 조건을 구현하였고, 선체모사구조물 및 음향센서에 설치된 표준 가속도계와 음향센서의 출력신호 측정을 통해 음향센서의 진동차단율, 삽입손실 및 진동민감도와 같은 성능지수를 산출하였다. 산출된 성능지수 결과를 토대로 음향센서의 주파수별 소음 차단 특성을 분석하고 실험 기법의 유효성을 검토하였다.

Keywords

GOHHBH_2019_v38n2_193_f0001.png 이미지

Fig. 1. Experimental configuration of the vibrationinduced noise isolation experiment in water.

GOHHBH_2019_v38n2_193_f0002.png 이미지

Fig. 2. Block diagram of the vibration-induced noise isolation experiment in water.

GOHHBH_2019_v38n2_193_f0003.png 이미지

Fig. 3. Coherence between acc. value from the impedance head and acc. values from accelerometers installed on the surface of the mock-up hull.

GOHHBH_2019_v38n2_193_f0004.png 이미지

Fig. 4. Acceleration transfer function of the sensors with the acoustic baffle in water: w/ and w/o vibration damping pad.

GOHHBH_2019_v38n2_193_f0005.png 이미지

Fig. 5. Insertion loss of the baffle assembly (acoustic baffle and vibration damping pad) in water.

GOHHBH_2019_v38n2_193_f0006.png 이미지

Fig. 6. Time data of output voltage from one of the acoustic receiving module of the sensors: (a) w/o the baffle assembly (acoustic baffle and vibration damping pad), (b) w/ the baffle assembly an w/o fixing mounts for the acoustic receiving module, (c) full sensor system.

GOHHBH_2019_v38n2_193_f0007.png 이미지

Fig. 7. Acceleration voltage sensitivity of the sensors with the acoustic baffle and vibration damping pad in water: comparison of results from each acoustic receiving module.

GOHHBH_2019_v38n2_193_f0008.png 이미지

Fig. 8. Acceleration voltage sensitivity of the sensors with the acoustic baffle in water: w/ and w/o vibration damping pad.

References

  1. R. D. Collier, "Ship and platform noise, propeller noise," in Handbook of Acoustics, edited by M. J. Crocker (A Wiley-Interscience Publication, New York, 1998).
  2. C. H. Sherman and J. L. Butler, Transducer and Arrays for Underwater Sound (Springer, Switzerland, 2016), pp. 279-300.
  3. J. Leader, J. Pan, P. Dylejko, and D. Matthews, "Experimental investigation into sound and vibration of a torpedo-shaped structure under axial force excitation," Proc. Meetings on Acoustics 19, 065059 (2013).
  4. J. W. Sohn, O. C. Kwon, and S. B. Choi, "Modal characteristics and vibration control of cylindrical shell structure: experimental results comparison in the air and water", Proc. Korean Soc. Noise Vib. Eng. Annual Spring Conference, 384-389 (2009).