Journal of the Society of Naval Architects of Korea (대한조선학회논문집)

The Society of Naval Architects of Korea (대한조선학회)
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Torsional Damping Estimation of a Segmented Hull Model with Modal Coupling

모드 연성을 수반하는 분할 모형의 비틀림 감쇠비 추정

  • Kim, Yooil (Department of Naval Architecture and Ocean Engineering, INHA University) ;
  • Park, Sung-Gun (DSME R&D Institute, Daewoo Shipbuilding and Marine Engineering, Co., Ltd.)
  • 김유일 (인하대학교 공과대학 조선해양공학과) ;
  • 박성건 (대우조선해양 중앙연구소)
  • Received : 2016.05.09
  • Accepted : 2016.10.24
  • Published : 2016.12.20
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Abstract

The identification of modal damping of a segmented hull model with torsional response is difficult task due to the coupling of modal response. This is because the 1st and 2nd torsional vibration modes are closely spaced in frequency domain leading to the situation that the modal decomposition is difficult to achieve by simple band-pass filter. Present study applied several different modal decomposition methods to derive the damping ratio of different modes. The modal decomposition methods considered in this study are simple band-pass filter, Hilbert vibration decomposition, Wavelet transform and proper orthogonal decomposition. Coupled free decay signal obtained from the torsional hammering test on a segmented hull model was processed with four different methods and the derived damping ratios were compared with each other. Discussions also have been made on the pros and cons of the different methodologies.

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References

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