| In recent years,gas turbine generator sets have been widely used in the field of energy power generation.However,due to the multi-disc tie rod structure of the gas turbine rotor,there are various non-linear factors in the rotor-bearing system,which may generate different power than the steam turbine rotor during operation.In the high-speed rotation of the gas turbine turbine rotor,the probability of failure will increase,which will cause hidden dangers in the operation of the rod rotor system.Traditional linear vibration theory has limitations in dealing with such nonlinear problems.It is of theoretical and practical significance to study the nonlinear dynamic characteristics of the drawbar rotor.Based on the theory of rotor dynamics,a multi-disc tie rod rotor dynamic model considering the interaction between the disks is established.The nonlinear dynamic characteristics of the rotor system under different system parameters are analyzed.,To understand the impact of typical faults such as rubbing on the rotor dynamic characteristics,improve the design and manufacturing level of gas turbine rotors and provide theoretical support for operational safety and reliability.The research content and research results of this article are as follows:(1)In view of the discontinuity of the tie rod rotor,the viscous contact between the discs will affect the stiffness of the rotor.The contact theory and preload force are used to calculate the contact stiffness between the discs and the sliding is considered.The non-linear oil film force of the bearing,the non-linear dynamic model of the dual-disc tie rod rotor flexural-torsional coupling was established,and the effects of rotor speed and unbalanced mass eccentricity on the non-linear dynamic characteristics of the system were calculated.(2)A more realistic non-linear dynamic model of the bending and torsional coupling of the three-disc tie rod rotor was established,and the effects of rotor speed and unbalanced mass eccentricity on the nonlinear dynamic characteristics of the system were calculated.Combining bifurcation diagrams,Poincare section diagrams,axial trajectory diagrams,and frequency spectrum diagrams,the nonlinear dynamic characteristics of the bending and torsional coupling of the three-disc tie rod rotor system and the two-disc tie rod rotor system are compared.There are some differences between the characteristics and the double-disc tie rod rotor at high speed.(3)For the double-disc tie rod rotor bearing system,the Drumbell principle and the Coulomb friction model are used to establish the nonlinear bending-torsional coupled vibration differential equation of the rubbing rotor,and then the differential equation is numerically calculated using the fourth-order Runge Kutta method.analysis.Combining bifurcation diagrams,Poincare section diagrams,axial trajectory diagrams,and frequency spectrum diagrams,the nonlinear dynamic characteristics of the bending-torsional coupling of the rub-down pull-down rotor bearing system are analyzed.Linear,the effect of torsional vibration of the rotor bearing system is negligible,and the rubbing force has gradually become the main factor affecting the nonlinear dynamic characteristics of the rotor;the eccentric mass of the disk and the radial stiffness of the stator also have a great influence on the nonlinear dynamic characteristics of the system.influences. |
