The Theoretical And Experiment Study On Dynamics Of Rub-impact Rotor System

The rotational machinery are widely used in many engineering fields, such as mechanism, power, aviation, spaceflight, etc. With the rapid advances of engineering and technology, the designs of rotating machinery are rapidly developing toward to large power, high speed and flexibility. Accordingly, the rotating machinery are often accompanied by the emergence of some breakdowns, which may cause serious damage to industry and usual life. So it’s full of important academic significance and actual engineering value to investigate the dynamics of rotor system. In this thesis we use two-disc rotor system as the research object.Using Newmark method to investigate the dynamics behavior of the rub-impact model of fixed-point. Simutaneously. using Runge-Kutta method to investigate the dynamics behavior of rub-impact two-disc rotor-bearing system. And make a further study on the dynamics of rotor system by experiment.The results of investment have provided good basis for the rotating machinery design and diagnosis. The main research works are as follows:(1) Introduce the purpose and meaning of studying on this paper.offer internal and overseas investigative situations of lump mass at the midspan of shaft.(2) A brief introduction on the basic theory and method of the rotor system dynamic’s.make a decision that using Newmark and Runge-Kutta method to study the rotor’s dynamics behavior.(3) two-disc system with rub-impact model was studied About the transfer model of stator rubbing. use Runge-Kutta method to research Rubbing single-span double disc rotor-bearing system dynamic behavior, through the time-domain waveform, spectrum, Poincare image, axes track, making a further analysis of the nonlinear oil film force and rubbing forces on the rotor system. According to the rubbing model of fixed-point, make a research on the impact of the stator stiffness, friction coefficient and clearance. (4) Do an test about the single-span two-disc rotor rubbing with stator, obtaining the rotor system dynamics behavior in different rub condition. At the same time,using the wavelet and power spectrum method to analyze the test results, get a further excavation of the dynamics of rubbing rotor system.(5) Finally,make a summary of this dissertation and point out the necessary research problems to go a step further.