| Summary: | 碩士 === 國立臺灣科技大學 === 機械工程研究所 === 83 === In this study, the blade is modeled as a pretwisted,tapered
beam, and the rotating speed of the blade is assumed as a
constant speed superimposed by a Gaussian white noise process.
First, the equation of motion is derived by Hamilton's
principle, then a one-term Galerkin method is utilized to
discretize the continuous system into a two degree of freedom
system. Next, by assuming the disturbance of rotating speed is
of small intensity, the Ito equations are obtained by the
method of stochastic averaging. Finally, the stability
boundaries of the system are decided by using the second moment
stability criteria and almost sure stability criteria,
respectively. The effects of system parameters on the stability
boundaries are studied numerically, and the relationship
between these two stability criteria is also investigated.
|
|---|
