Studies On Earthquake Response And Some Non-linear Dynamics Problems In Elastic Rotor System

Rotating Machinery is the important power machinery in modern industry.It has broad application in industry such as machinery, electric power, traffic, aviation, chemical industry, and the sources of energy, mining industry, and war industry. With the development of science and technology and modernized industry, Rotating machinery is developing to direction of high-speed-lization, light-lization, centralizes to large-scale-lization, melting in a row, the automation draws high-power, big load. Once these equipment malfunctions because of nonlinearity bump against rub or the earthquake random excitation,economic losses is enormous. At present, scholarships pair rotation subsystem dynamics characteristic property has carried out large amount of research, has got gratifying research result.Casing (basis) has certain flexibility per se originally, some Rotating Machinery such as aero motor’s casing have bigger flexibility, because of difficulties in study, people often regard the casing as no deformable rigid body, such treatment is bound to bring about bigger error to the result calculating analysis. Exactly be casing has certain flexibility per se, the vibration of the rotator and machine affect mutually, which requires regarding the rotator and casing as the unified entirety, and study it’s dynamics characteristic property. Thinking to some mechanical actual peculiar rotating structure forms, we shouldn’t ignore the casing self elasticity, the effect that the elastic linkup pair rotation subsystem between the casing and the stator responds to, should not ignore the effect when the disk non-symmetrical arrangement of the gyroscopic torque produced. Thinking that rotation shaft elasticity, axle bearing elastic foundation, elastic foundation, the linkup elasticity and top force moment cantilever pair of asymmetric set20liberty degree rotators system among the stator and the base, which we call elastic rotator system. At present, research on the elastic characteristics of the rotor system dynamics, On the consideration of other reasons due to manufacturing errors caused by random dynamic excitation rotary bearing and non-Coulomb excitation of friction, the analysis about earthquake responds of the rotator system, study at present is not enough sufficient. Therefore, the dissertation is based on practical engineering background, some systematic experiment platform nonlinearity dynamics relevance problem has carried out research on the elastic rotator system and asymmetric rotator. The main work is as follows:(1) Building a Mechanics model by considering that rotation shaft elasticity, axle bearing elastic foundation, elastic foundation, the linkup elasticity and top force moment cantilever pair of asymmetric set20liberty degree rotators system among the stator and the base (be called elastic rotator system);(2) Bringing forward the dynamic excitation of axle bearing gyration model, establishing a flexible slewing bearing rotor system dynamic incentives, and differential equations of motion of Local Rub Coupling Faults of the system and imbalances. By applying Numerical Analysis, analyzing the stiffness rotator system and elastic rotor system about amplitude-frequency characteristic with touch the ramification rubbing and chaotic behavior of part, proposing the concept of quasi-periodic chaos. Analyzing the evolution of the quasi-periodic motion for the chaotic process;(3) Analyzing Coulomb friction model and non-Coulomb friction model of non-elastic rotor system’s the bifurcation and chaotic behavior in both cases respectively, in order to qualitatively confirm the numerical results, doing the experimental study of local rubbing;(4) Adopting method of integration of suppositional excitation with numerical integration, and analyzing the elastic rotator system’s stimulates in the unbalanced random excitation bearing rotary stochastic dynamic excitation, the systematic frequency region and time domain random respond due to stable or non-stationary seismic excitation;(5) According to stability theory, based on the nature of the state matrix Eigen values, analyzing a number of structural parameters’impact on the elastic non-rub rotor system stability; Based on Jacobi matrix the nature of Eigen values, analyzing some of the parameters impact on the rub elastic stability of rotor system of solutions; and using the system step response and pole-zero distribution, discriminate intuitively rubbing stability of elastic rotor system movement; proposed the concept of critical bearing stiffness;(6) Using precise integration method, analyzing some parameters of elastic rotor system impact on the transient response. Proposing the concept of conversion of the odd array of non-harmonic and conversion of gravity and non-odd arrays;(7) Using numerical analysis method, analyzing a number of structural parameters of elastic rotor system impact on the non-symmetric bifurcation bearing rotor experimental system and the behavior of chaotic dynamics, and experimentally verify the behavior of the system movement.