Transactions of the Korean Society for Noise and Vibration Engineering (한국소음진동공학회논문집)

The Korean Society for Noise and Vibration Engineering (한국소음진동공학회)
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Dissipation Effects Induced by Substructures Comprised of Multiple oscillators

다수의 진동체로 구성된 부 구조물에 의한 감쇠 효과

  • 최성훈 (한국과학기술원 기계공학과) ;
  • 김양한 (한국과학기술원 기계공학과)
  • Published : 2002.06.01
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Abstract

The goal of this paper Is to characterize the vibration damping induced in a main structure by a large number of sub-oscillators. A simple expression is obtained for the substructure impedance when the number of sub-oscillators approaches Infinity. It is found that the induced damping depends on the total mass of the sub-oscillators resonating in a frequency band of interests and nearly independent of their Individual loss factors. A modal overlapping condition. which corresponds to bandwidths that exceed the spacing of those natural frequencies, is required for the sub-oscillators to have such effects. An impulse response of the system is also considered. When the sub-oscillators lack damping and do not satisfy the modal overlapping condition, the vibratory energy is returned from the sub-oscillators to the main structure at later times. The result of this paper is consistent with that found with the fuzzy structure and SEA framework.

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References

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