The dynamic model of a pedestal looseness rotor system is built and the dynamics of the system near the resonance region is analyzed using the KBM method. Then the asymptotic method to study a dynamic system with slow...The dynamic model of a pedestal looseness rotor system is built and the dynamics of the system near the resonance region is analyzed using the KBM method. Then the asymptotic method to study a dynamic system with slow-changing parameters is used to study the starting and braking course of the system. Finally, the analytical results are proved by experiment. The results can be used in the inspecting and fault diagnosis of a rotor system of this type.展开更多
The transient proper orthogonal decomposition(TPOD) method is used to study dynamic behaviors of the reduced rotor-bearing models,and the fault-free model is compared with the models with looseness fault.A 22 degree o...The transient proper orthogonal decomposition(TPOD) method is used to study dynamic behaviors of the reduced rotor-bearing models,and the fault-free model is compared with the models with looseness fault.A 22 degree of freedoms(DOFs) rotor model supported by bearings is established.Both one end and two ends pedestal looseness of the liquid-film bearings are studied by analyzing the time history and the frequency-spectrum curves.The effects of the initial displacement and velocity values to frequency components of the original systems and the dimension reduction efficiency are discussed.Moreover,the effects of variation of initial conditions on the efficiency of the TPOD method are studied.Reduced models can provide guidance significance from the perspectives of the theory and numerical simplification to discuss the characteristics of pedestal looseness fault.展开更多
文摘The dynamic model of a pedestal looseness rotor system is built and the dynamics of the system near the resonance region is analyzed using the KBM method. Then the asymptotic method to study a dynamic system with slow-changing parameters is used to study the starting and braking course of the system. Finally, the analytical results are proved by experiment. The results can be used in the inspecting and fault diagnosis of a rotor system of this type.
基金Sponsored by the National Basic Research Program of China(Grant No.2015CB057400)
文摘The transient proper orthogonal decomposition(TPOD) method is used to study dynamic behaviors of the reduced rotor-bearing models,and the fault-free model is compared with the models with looseness fault.A 22 degree of freedoms(DOFs) rotor model supported by bearings is established.Both one end and two ends pedestal looseness of the liquid-film bearings are studied by analyzing the time history and the frequency-spectrum curves.The effects of the initial displacement and velocity values to frequency components of the original systems and the dimension reduction efficiency are discussed.Moreover,the effects of variation of initial conditions on the efficiency of the TPOD method are studied.Reduced models can provide guidance significance from the perspectives of the theory and numerical simplification to discuss the characteristics of pedestal looseness fault.