Study on Fretting Wear of Contact Interface of Curvic Coupling for Circumferential Rod Combined Rotor

Fretting wear is a general surface damage form in tightly connected structures. Aimed at the curvic coupling of the disks in combined rotor gas turbine, using the finite-element method and Archard wear theory, the effects of the bolt preload, torque, and transverse vibration on the fretting characteristics of curvic coupling were studied. Additionally, the influences of a single mistuned tie rod and the material properties on the fretting characteristics of curvic coupling have been researched. Finally, a two-disk rotor experiment was carried out to make a comparative study with the simulation. The results showed that with the increase of preload and torque, the contact stress, slide distance, and wear depth gradually increased. Moreover, when the single rod was mistuned, it caused the uneven distribution of fretting characteristics in the circumferential direction. Compared with the Poisson's ratio and density, the elastic modulus had a notable influences on the fretting characteristics. Comparing the experiment and the transverse lateral load simulation, the simulation results were consistent with the experimental results.

Automated summary

This study investigates the effects of bolt preload, torque, and transverse vibration on the fretting characteristics of curvic coupling in a combined rotor gas turbine using the finite-element method and Archard wear theory. The influences of a single mistuned tie rod and the material properties on the fretting characteristics are also examined. The results show that increasing the preload and torque leads to higher contact stress, slide distance, and wear depth. Mistuning in a single rod causes uneven distribution of fretting characteristics. Additionally, the elastic modulus has a notable impact on the fretting characteristics, compared to Poisson's ratio and density. The simulation results are consistent with the experimental findings.