Dynamic Analysis Of Multi-rotor System With Axial Constraint

Bearing-rotor system is the most vital component of large rotating machinery. It is widely applied in the machines such as aeroengines, industrial compressors and electromotors. It plays an important role in national economic fields, for example: power, aviation, machine, chemistry, spin and so on. Because the vibration of rotors bring plenty expense which can be avoided, it is of significance to research dynamics of multi-rotor system with axial constraint.Firstly, the dissertation analyzes statics speciality of multi-rotor system with axial constraint. Multi-rotor dynamic model with axial constraint is set up and the differential equations are deduced. The results show that static state flexibility and load distribution among the bearings are influenced on the effect of axial constraint, and then stiffness and damper coefficient are changed.The study on critical speed and mode, transfer matrix method is recommended, and a MATLAB program is designed. The conclusions indicate that axial constraint improves critical speed of rotor system. The study on stability, the conclusions illuminate that axial constraint meliorates stability of rotor system.Influences on the amplitude of the unbalanced response are emphatically analyzed. The results are as follows. At the low speed moment of rotor system axial constraint can control unbalance response, but it is not remarkable. After great amplitude of sympathetic vibration region, axial constraint controls unbalance response and it is very prominent. With improving speed, axial constraint can also impact on the balance of the rotor system to a certain extent. We can fully make use of the function of axial constraint in engineering application.