경계요소 해석과 진동 실험을 이용한 단순 평판의 방사 음향 예측

Estimation of sound radiation for a flat plate by using BEM and vibration experiment

  • 김관주 (홍익대학교 공과대학 기계공학과) ;
  • 김정태 (홍익대학교 공과대학 기계공학과) ;
  • 최승권 (홍익대학교 일반대학원 기계공학과)
  • 발행 : 2000.10.01

초록

BEA(Boundary Element Analysis) based on Kirchhoff-Helmholtz integral equation is widely used in the prediction of sound radiation problems of vibrating structures. Accurate estimation of sound pressure distribution by BEA can be [possible if and only if dynamic behavior of the relating structure was described correctly. Another plausible method of sound radiation phenomena could be the NAH(Nearfield Acoustic Holography) method. NAH also based on the identical governing equation with BEA could be one of the best acoustic imaging schemes but it has disadvantages of the complexity of measurement and of the need of large amount of measuring points. In this paper, modal expansion method is presented for taking accurate dynamic data of the structures efficiently. This method makes use of vibration principle an arbitrary dynamic behavior of the structure is described by the summation of that structures mode shapes which can be calculated by FEA easily and accurately. Sound pressure field from a vibration flat plate is calculated using the combination of vibration signal on that flat plate from experiment, and of the natural mode shapes form FEA. When sound pressure field from vibration signal is calculated the importance of the phase information was emphasized.

키워드

참고문헌

  1. 한국소음진동공학회지 v.6 no.6 소음원 규명 방법론;통합된 개념 및 특성들 김양한
  2. NIT Technical Paper Modal Expanison of Experimental Vibration Data for Numerical Acoustic Radiation Prediction Pierre Guisset;Marc Brughmans
  3. MSC World User's Conference Comparing Acoustic Measurements with Combined MSC/NASTRAN-SYSNOISE Sound Radiation Predictions of an Engine Block P. Guisset;J. P. Roisson;H. Wynendaete
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