Research On Some Dynamic Characteristics Of Complex Rotor System

Rotating machinery is one of the most important equipment in national foundation establishment and industry, such as steam turbine, aero-engine and so on.The actual rotor system generally have very complex geometry.At the same time due to frequent start and stop and other reasons, the dynamic characteristics of rotor system will change,so that it is important to use appropriate methods to analysis the dynamics characteristics of complex rotor system.In addition,due to the frequent occurrence of rub-impact fault of complex rotor system,the research of nonlinear dynamic characteristics of rub-impact is very important.In this paper,using the complex rotor with a certain engineering significance as a model rotor system,combined with the advantages of transfer matrix method and modal synthesis method, using transfer matrix-modal synthesis method for solving dynamic characteristics of complex rotor system.using of ANSYS finite element analysis software to verify the results of transfer matrix-modal synthesis method.and studying the steady-state temperature field under the dynamic characteristics of complex rotor system.At the same time, using the idea of modal synthesis method,simplified the freedom of complex rotor system.analysising the nonlinear characteristics of multi-disk rotor system.The main work as follows:(l)Using of transfer matrix-modal synthesis method to analysis the critical speed, vibration mode, as well as steady-state unbalance response of double-rotor system and the double-rotor system with a deformity structure, through the comparison with the results of transfer matrix method and use of ANSYS finite element analysis software for modeling, showing that the accuracy and the superiority of transfer matrix-modal synthesis method in complex rotor system.(2)Using of transfer matrix-modal synthesis method to analysis the complex rotor system in the steady-state rotor temperature field, due to thermal stress and thermal deformation caused by changes in dynamic characteristics of the system. Comparing with the critical speed and unbalance response mode shape results without considering the temperature, showing that changes in temperature of the system can not be ignored.(3) Using the idea of modal synthesis method to analysising the complex rotor system with nonlinear rubbing impact problem. To a single six-disc rotor system as an example, simplifying the model and reduce the degree of freedom,analysis its nonlinear dynamic characteristics, and discuss the impaction of non-linear dynamic characteristics when different plate rubbing occurs and the parameters of the system are changed.