Laboratory for Dynamics of Machines and Structures 
Spatial damping identification in the frequency domain - A Theoretical and Experimental Comparison
 M. Brumat, J. Slavič and M. Boltežar
Journal of Sound and Vibration, 376:182 - 193, 2016

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Abstract
This paper deals with spatial damping identification methods. In contrast to the commonly used damping methods (modal, proportional) the spatial damping information improves structural models with a known location of the damping sources. The Lee-Kim, Chen-Ju-Tsuei, Fritzen IV and local equation of motion methods were theoretically and experimentally compared. Experimentally, the spatial damping identification was tested against: modal and spatial incompleteness, differences in viscous and hysteretic damping models, the performance of identification methods and the effect of damping treatments. It was found that for a structure with a known equation of motion (beam, plate) the local equation of motion method is more efficient and gives a more precise location of the damping. Full frequency response function (FRF) matrix methods can also identify the spatial damping, but are more demanding because the numerical and measurement effort increases with n 2 , where n is the number of measurement points and, consequently, the size of the FRF matrix.
Authors

System Engineer Space Mechanisms

Matija Brumat, PhD

  Synopta Gmbh
  matija.brumat@synopta.ch
  +386 1 4771 230
matijabrumat    
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Associate Professor

Janko Slavič, PhD

  Ladisk, Faculty of Mechanical Engineering, University of Ljubljana
  janko.slavic@fs.uni-lj.si
  +386 1 4771 226
jankoslavic     jankoslavic    
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Professor

Miha Boltežar, PhD

  Ladisk, Faculty of Mechanical Engineering, University of Ljubljana
  miha.boltezar@fs.uni-lj.si
  +386 1 4771 608
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