Reduced order modeling of blades with geometric nonlinearities and contact interactions

This article presents a methodology dedicated to the vibration analysis of turbomachine blades accounting for both geometric nonlinearities and nonlinear blade-tip/casing contacts in numerically efficient way through use reduced order models. Contact is handled with Lagrange multipliers equation motion integrated forward time using an explicit central difference integration scheme. Nonlinear internal forces caused by large displacements are evaluated stiffness evaluation procedure. Three reduction techniques compared this article, namely extension Craig–Bampton method, proper orthogonal decomposition modal derivatives-based approach. These numerical methods applied on open industrial compressor blade model, NASA rotor 37 blade, promote reproducibility results. The first subjected harmonic excitation, without contact interactions. An indicator local global comparison criteria defined more easily compare performance each method. When also contacts, presented results underline that approach particularly well-suited accurate description blade’s dynamics. method then employed in-depth response over wide angular speed range considering typical scenario. Obtained feature frequency domain signals along stress fields. They suggest has strong impact prediction initiated