In order to suppress unbalance response of rotor-bearing system caused by synchronous revolution of residual unbalance
a method
which is based on a hybrid flexure pivot-tilting pads bearing and considering increase the eccentricity to increase the oil film stiffness so that suppress unbalance response
is proposed. First
the oil film pressure distribution model is obtained by combining flow balance principle with Reynolds equation
and the torque equilibrium equation of pads and rotor movement function are built. Then
the standard transfer function of the simplified rotor-bearing system is deduced according to its differential equation of motion. Finally
the positioning strategy of desired position of rotor center is studied in order to determine the eccentricity control scheme
and the position-control force equation is fitted by the method of least squares. Results show that the proposed positioning method can achieve high positioning accuracy. Oil film stiffness can be improved by increasing the eccentricity and the unbalance response of the rotor-bearing system can be effectively restrained. The vibration amplitude of x and y direction are both reduced to about 10% of the original.
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