Phenomenological model for stability analysis of bladed rotor-to-stator contacts

Marie-Océane Parent (1) , Fabrice Thouverez (2)

1 SNECMA Villaroche [Moissy-Cramayel]
2 LTDS - Laboratoire de Tribologie et Dynamique des Systèmes

The present study aims to predict the dynamic stability of a turbofan engine submitted to light contacts between fan blades tips and their surrounding casing. The study is based on a hybrid model which introduces a simplified bladed wheel and a flexible suspended casing to a rotor-shaft model. Inertial coupling is considered between blades and shaft dofs and an elastic link is introduced between the shaft and the suspension dofs of the casing. A 3D contact formulation has been implemented to recover accuracy in the contacts detection and the application of contact forces; it considers the 3D model kinematic and introduces the local geometry of the contact area. The model behavior with blade-to-casing contacts is analyzed through two approaches: the first one assumes permanent contacts while the other one allows intermittent contacts. Good agreement is obtained between the two types of results. The results highlight the importance of couplings in the initiation of unstable phenomena and the relevance of the 3D contact formulation in predicting the stability of the system.

Mots clés: Rotordynamics; Bladed assembly; Blade-tip/casing contacts

Domaines: Mécanique [physics.med-ph]

Marie-Océane Parent, Fabrice Thouverez. Phenomenological model for stability analysis of bladed rotor-to-stator contacts. International Symposium on Transport Phenomena and Dynamics of Rotating Machinery, Apr 2016, Honolulu, United States. ⟨hal-01537643⟩