Nonlinear modal analysis of mistuned periodic structures subjected to dry friction

Colas Joannin (1, 2) , Benjamin Chouvion (1) , Fabrice Thouverez (1) , Moustapha Mbaye (2) , Jean-Philippe Ousty (2)

1 LTDS - Laboratoire de Tribologie et Dynamique des Systèmes
2 Turbomeca

This paper deals with the dynamics of a cyclic system, representative of a bladed-disk subjected to dry friction forces, and exhibiting structural mistuning. The nonlinear complex modes are computed by solving the eigenproblem associated to the free response of the whole structure, and are then used to better understand the forced response to a traveling wave excitation. Similarly to the underlying linear system, the tuned model possesses pairs of modes that can be linearly combined to form traveling waves, unlike those of the mistuned structure. However, due to the nonlinearity, the modal properties are not constant but vary with the vibration amplitude in both cases. A qualitative analysis is also performed to assess the impact of the mistuning magnitude on the response, and suggests that further statistical investigations could be of great interest for the design of bladed disks, in terms of vibration mitigation and robustness.

Mots clés: nonlinear modes; mistuning; friction; bladed disk

Domaines: Mécanique des structures [physics.class-ph]; Vibrations [physics.class-ph]

Colas Joannin, Benjamin Chouvion, Fabrice Thouverez, Moustapha Mbaye, Jean-Philippe Ousty. Nonlinear modal analysis of mistuned periodic structures subjected to dry friction. Journal of Engineering for Gas Turbines and Power, 2015, ⟨10.1115/1.4031886⟩. ⟨hal-01260983⟩