Analysis of rubbing failure characteristics of turbine rotor system based on a mixed-nodes boundary feature method

Abstract Investigating the rubbing failure characteristics in turbine rotors holds significant implications for ensuring the operational integrity and reliability of aero-engine systems. A mixed-nodes boundary feature method (MNBFM) was proposed to investigate the dynamic characteristics of rotors experiencing rubbing failure. In this approach, the key components of the turbine pump are modelled as flexible bodies, with their surface profile nodes and connection nodes systematically organized and integrated. Then, the dimension reduction of the components is realized through the Craig-Bampton method, and the dynamic characteristics of the turbine rotor under various dynamic rub-impact parameters and loading conditions are investigated. The results reveal that: (1) The optimized model significantly reduces file size and computation time while maintaining high response accuracy. (2) the trajectory of the axis after rubbing exhibits a noticeable clipping phenomenon. (3) Higher rotational speed intensified the rubbing frequency and increase the amplitude of individual rubbing events. In addition, the rubbing force shows the intermittent characteristic of jump attenuation.