Abstract

The objective of this study is to carry out modal analysis of
nonlinear periodic structures using nonlinear normal modes
(NNMs). The NNMs are computed numerically with a method
developed in [18] that is using a combination of two
techniques: a shooting procedure and a method for the
continuation of periodic motion. The proposed methodology is
applied to a simplified model of a perfectly cyclic bladed disk
assembly with 30 sectors. The analysis shows that the
considered model structure features NNMs characterized by
strong energy localization in a few sectors. This feature has no
linear counterpart, and its occurrence is associated with the
frequency-energy dependence of nonlinear oscillations.