| The large rotating machinery is the symbol of the developed level of the national equipment manufacturing industry.However,the large rotating machinery still has poor stability,multiple faults and other issues.As a core component of rotating machinery,the stable operation of the rotor system is one of the key factors to ensure the stability of large-scale rotating machinery.The rotor system in high speed operation will inevitably exist vibration problems,can cause the machine halt and even a serious accident crash serious.Therefore,in order to ensure the stable operation of the unit,the vibration of the rotor system must be effectively controlled.Changing rotor system parameters is a common method for rotor vibration control.Widely used variable rheological fluid damping device or permanent magnet variable stiffness device,there are particles floating sink,the magnet installation requires more space and other issues,therefore,a more simple variable parameter control method is urgently needed.In this paper,a new structure of MRE elastomer dynamic vibration absorber is proposed.The passive and semi-active control of the vibration of the rotor system is studied based on the magnetorheological effect of MRE elastomer and its stiffness and damping changeable characteristics.The specific work is as follows:(1)The formulation proportion of MRE was discussed,the vibration test platform was set up,the dynamic mechanical properties of MRE were tested,and the variation of stiffness and damping of MRF under high frequency excitation was analyzed emphatically;the data fitting of Bouc-Wen model is studied by LM algorithm,and the mechanical model that can approximate the dynamic characteristics of MRE is obtained.(2)The structure of a new MRE absorber was designed,the dynamic equation of the MRE absorber-rotor system was established,and the working principle of the absorber was analyzed.Through the numerical simulation,the influence of external magnetic field strength,iron powder content,installation location of vibration absorber and other factors on the natural frequency and vibration amplitude of the rotor system is analyzed.(3)The MRE vibration absorber-Bently rotor system experimental platform was set up.The influence of MRE vibration absorber(external magnetic field strength,Carbonyl iron powder mass fraction,vibration absorber mounting position,etc.)on the vibration absorption effect of rotor system was investigated by means of experimental research.The experimental results verify the theoretical analysis results.(4)The semi-active control of the vibration absorption of rotor system by PID control algorithm is studied.The experiment is carried out to verify the effectiveness theory of the Magnetorheological effect principle and the control algorithm.First,the stability of the PID control program and the frequency shift of the MRE vibration absorber mechanism to the rotor system are verified by the experiment..Then,the parametric analysis of the vibration absorber is verified,and the validity of the PID control is verified by the test under the condition of constant speed and variable speed.(5)The subject uses the intelligent material MRE as a strategic means to study the broadband vibration suppression of the rotor system.The preparation and mechanical model of magnetorheological elastomer are discussed.The dynamic equation of rotor vibration absorber is established by using the Bouc-Wen model as the mechanical model of MRE vibration absorber,and the working principle of the absorber is analyzed.Secondly,the MRE elastomer vibration absorber-Rotor System experimental platform is set up,and the PID control program is compiled.The MRE elastomer absorber effectiveness experiment and rotor running process control experiment are carried out by the experimental research method.The results show that the prepared MRF vibration absorber can reduce the rotor amplitude effectively,and the vibration suppression effect is 73%. |
PDF Full Text Request