On the vibration of rotating blade with torsionally-flexible shaft

The problem of rotating blade vibrations under the effect of shaft torsional flexibility is addressed, theoretically, in this paper. A previously developed nonlinear dynamic model is reduced to a one-ordinary differential equation that describes the rotating blade vibration. The obtained equation is of Mathiu-type ordinary differentia equation with harmonically variable coefficients. The equation is simulated for different rotating speeds and showed regions of unstable blade vibrations. The proposed simplified equation can be adopted for design, development and diagnostics purposes of rotor systems with rotating flexible blades and shaft torsional vibration excitations.