Identification of Reduced Models from Optimal Complex Eigenvectors in Structural Dynamics and Vibroacoustics
The objective of this chapter is to present some efficient techniques for identification of reduced models from experimental modal analysis in the fields of structural dynamics and vibroacoustics. The main objective is to build mass, stiffness and damping matrices of an equivalent system which exhibits the same behavior as the one which has been experimentally measured. This inverse procedure is very sensitive to experimental noise and instead of using purely mathematical regularization techniques, physical considerations can be used. Imposing the so-called properness condition of complex modes on identified vectors leads to matrices which have physical meanings and whose behavior is as close as possible to the measured one. Some illustrations are presented on structural dynamics. Then the methodology is extended to vibroacoustics and illustrated on measured data.
KeywordsStructural Dynamic Complex Mode Matrice Identification Left Eigenvector Inverse Procedure
The authors would like to thank Jean-Loïc Le Carrou from Laboratoire d’Acoustique Musicale (Paris VI) and François Gautier from the Laboratoire d’Acoustique de l’Université du Maine, for the fruitful discussions and for allowing us to use their measurements data, used in the last part of the chapter.
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