A method to predict the non-linear vibratory response of bladed disc system with shrouded dampers

The prediction accuracy of the non-linear vibratory response of bladed disc system with shrouded dampers depends on the modelling of bladed disc system, the friction contact model for depicting the non-linear constraint force, and the solution method of non-linear vibration equations of the bladed disc system. In order to improve the computation efficiency, the bladed disc system is assumed to be tuned in this article. Under this assumption, the vibratory response of the bladed disc system can be predicted based on a sector model having the cyclically symmetric constraint. This article particularly describes the formulation of the sector model and the infliction of cyclically symmetric constraint. The proposed three-dimensional (3D) friction contact model used to depict the non-linear constrained force is a numerical method, in which the relative motion of the contact surfaces is an arbitrary complex periodical one. The hybrid frequency-time domain (HFT) method is applied to solve the non-linear vibration equations of the bladed disc system for its high computation efficiency and computation accuracy. Finally, based on the sector model, numerical 3D friction contact model, and HFT domain method, a method is developed to predict the non-linear vibratory response of the bladed disc system with shrouded dampers.