Taking a rotor-blade-casing coupling system as the research object
finite element model of the rotor-blade-casing coupling system was established by ANSYS software
and then the validity of the model was verified by the natural frequencies obtained from experimental measurement. A point-point contact element was used to simulate the fixed-position rubbing fault between the blade and the casing
and further the validity and feasibility of the method adopted were also verified by the testing response data. Finally
the influences of different penetrations at a certain rotate speed
the constant penetration at different rotate speeds and the constant clearance at different rotate speeds on system vibration responses were analyzed. The results show that rubbing on the tip of blade mainly excites high multiple frequency components
and the amplitude of the multiple frequencies near the pitching rigid model increases. Under the constant penetration at different rotating speeds
the frequency components of the system is reduced at high speed rubbing conditions
and the normal rubbing force also changes with the increase of rotating speed. Under the constant clearance at different rotating speeds
the amplitudes of some multiple-frequency components are greater than those of rotating frequency when the rubbing appears at high speed
and repeatedly collision rebound can be observed during continuous rubbing.