Analyse modale non linéaire expérimentale - Bibliothèque Ecole ...

4TITRE et RESUME en anglais:Expérimental non-linear modal analysisIntroducing modal analysis in the context of non-linear mechanical structures may appearlike a paradox. That because the several methods which can be put behind this term apply oniyin the case where the system under study can be considered like a linear one. Gathering "modalbases" by means of these widely spread methods is very useful in the domain of engineeringfor many reasons : dynamic caracterisation of structures, response prediction, sub-structuring,model updatingIn the meantime, the extension of the vibration mode concept, developed in the 60's, to aparticular class of non-linear systems is less known. Linear systems' modes appear then as aparticular case of non-linear modes which are defined as motions with some particularities andwhose existence have been verified. More recently, several advancement, mostly analytical, havebeen carried out in the study of dynamical systems using non-linear normal modes.Actual structures often exhibit some non-linear behavior that may lead to potential difficultiesin modeling and analysis. So, it seems important, to look for the usefulness, the applicabilityand the efficiency of methods based on extended modal concepts in an experimental and industrialcontext.In this work, some non-linear normal mode computing technics are shown and applied toexperimental, and afterwards to industrial cases, after some appropriate vibratory tests.We show some possibilities and some limits in the experimental analysis of vibrating structuresusing non-linear modal concepts.DISCIPLINE:MécaniqueMOTS-CLES:MODES NON-LINEAIRES, IDENTIFICATION, EXPERIMENTAL, ANALYSE MODALE.INTITULE ET ADRESSE DU LABORATOIRE:Laboratoire de Tribologie et de Dynamique des Systèmes (LTDS)Ecole Centrale de lyon36 avenue Guy de Collongue69134 Ecully CedexFRANCE