This paper focuses on the modelling of harmonic vibration of two rotating blades affected by friction in contact of a rigid body placed in between the blade shroud. Harmonic blade excitation uniformly distributed in blade nodes in circumferential and axial direction is supposed. Flexible blades are discretized by FEM using 1D Rayleigh beam elements. The nonlinear friction forces in contact surfaces between the blade shroud and the friction element are taken into account using the harmonic balance method. Orbits of central contact points and dissipation energy are investigated in dependence on the excitation frequency. Dissipation energy amount in contact surfaces is confronted with blade tips vibration. and Obsahuje seznam literatury
The aim of the paper is to show the influence of design parameters on the suppression of rotating blade vibration. The derivation of nonlinear mathematical model of a blade couple mutually connected by a friction element is summarized. After that, the linearization of the mathematical model is performed by harmonic balance method. The linearized model is used for sensitivity analysis of real and imaginary parts of eigenvalues in the course of rotation and sensitivity analysis of stead-state response with respect to the design parameters of internal friction coupling. and Obsahuje seznam literatury