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Development of an Improved NDIF Method for Efficiently Extracting Eigenvalues and Eigenmodes of Arbitrarily Shaped Acoustic Cavities

임의 형상 음향 공동의 효율적인 고유치 및 고유모드 추출을 위한 개선된 NDIF법 개발

  • 강상욱 (한성대학교 기계시스템공학과) ;
  • 윤주일 (한성대학교 기계시스템공학과)
  • Received : 2011.08.08
  • Accepted : 2011.09.19
  • Published : 2011.10.20

Abstract

An improved NDIF method is introduced to efficiently extract eigenvalues and eigenmodes of two-dimensional, arbitrarily shaped acoustic cavities. The NDIF method, which was developed by the authors for the eigen-mode analysis of arbitrarily shaped acoustic cavities, membranes, and plates, has the feature that it yields highly accurate eigenvalues compared with other analytical methods or numerical methods(FEM and BEM). However, the NDIF method has the weak point that the system matrix of the NDIF method depends on the frequency parameter and, as a result, a final system equation doesn's take the form of an algebra eigenvalue problem. The system matrix of the improved NDIF method developed in the paper is independent of the frequency parameter and eigenvalues and mode shapes can be efficiently obtained by solving a typical algebraic eigenvalue problem. Finally, the validity and accuracy of the proposed method is verified in two case studies, which indicate that eigenvalues and mode shapes obtained by the proposed method are very accurate compared to the exact method, the NDIF method or FEM(ANSYS).

Keywords

References

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  2. Extraction of Highly Accurate Eigenvalues of Arbitrarily Shaped Acoustic Cavities with a Mixed Boundary vol.28, pp.5, 2018, https://doi.org/10.5050/KSNVE.2018.28.5.542
  3. Eigenvalue Analysis of Arbitrarily Shaped, Acoustic Cavities Using Two-domain Method vol.28, pp.4, 2018, https://doi.org/10.5050/KSNVE.2018.28.4.410