Journal of the Computational Structural Engineering Institute of Korea (한국전산구조공학회논문집)

Computational Structural Engineering Institute of Korea (한국전산구조공학회)
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Formulation of a Wittrick-Williams Algorithm for Computing Natural Frequencies of an Active Beam

능동보의 고유진동수 계산을 위한 휘트릭-윌리엄즈 알고리듬의 유도

  • 김주홍 (인하대학교 산업과학기술연구소) ;
  • 이우식 (인하대학교 기계공학부)
  • Published : 2002.12.01
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Abstract

In this paper, a Wittrick-Williams algorithm is developed for the spectral element model of an elastic-piezoelectric two-layer active beam. This algorithm may help calculate all the required natural frequencies, which lie below any chosen frequency, without the possibility of missing any due to close grouping or due to the abrupt sign changes of the determinant of spectral element matrix via infinity instead of via zero. A uniform active beam and a partially patched active beam are considered as the illustrative examples to confirm the present algorithm.

구조물의 고유진동수가 너무 밀집되어 있거나 특성방정식의 부호가 영을 지나지 않고 갑자기 무한대가 되는 등의 불연속성이 존재하는 주파수 대역에 속해있는 고유진동수를 단순히 근을 찾는 수치해석 알고리듬만을 이용하여 모두 찾아내어 계산한다는 것은 그다지 쉬운 일이 아니다. 따라서, 본 연구에서는 이러한 문제점을 극복할 수 있는 휘트릭-월리엄즈 알고리듬을 탄성재층과 압전소자재층의 두개의 층이 적층되어 구성된 능동보의 스펙트럴요소모델에 대하여 유도하였다 유도된 알고리듬은 균일적층 능동보와 부분적층 능동보의 두 경우에 적용하여 그 결과를 평가하였다.

Keywords

References

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