Analysis of Vibration Characteristics of Blade under Rotor Motion
Journal of Mechanical Engineering
The nonlinear dynamic characteristics of aero engine blades under rotor excitation are studied. Using the large deflection nonlinear relation and the first order piston theory of supersonic flow, the continuum model of blade is established by using Hamilton principle and simplified to a single degree of freedom model by Galerkin method. The first order approximate equation for resonance amplitude frequency response of blades under the combined action of parametric excitation and forced
... and forced excitation is derived by means of multi-scale method. The influence of the amplitude of the torsional angle, the steady speed of the rotor, the velocity of gas flow and the shape parameters of the blade on the amplitude-frequency response characteristics of the blade are analysed. Through analytical and numerical analyses, it is shown that the presented parameters are sensitive parameters for the dynamical properties of blades. At the same time, by using the singularity theory, the transition set and bifurcation diagram of the principal parametric resonance-primary resonance steady-state response of the system are obtained, and the experimental analysis of the blades under low flow velocity is carried out.