Comparative Analysis of Rub-Impact Dynamics of Shrouded Blades Based on the Bilinear Hysteresis Model and the Coulomb Friction Model

The bilinear hysteresis friction model and the Coulomb friction model are two typical macro slip models which are widely used by researchers in simulation analysis of rub-impact dynamics of shrouded blades. However, differences in the simulation results of shrouded blades based on these two friction models have not well been studied recently. In this paper, a two-dimensional lumped mass model of shrouded blades including axial displacements and tangential displacements is established, and the kinetic equations of the blades under different contact conditions are derived. The contact-separation and stick-slip transition points are determined by the bisection method. Using the fourth-order Runge–Kutta method, comparative analysis of the nonlinear characteristics and the vibration reduction characteristics of shrouded blades based on the bilinear hysteresis friction model and the Coulomb friction model are carried out. Numerical simulation results indicate that the nonlinear characteristics and the vibration reduction characteristics of shrouded blades based on these two friction models are not accordant. The discussion in this paper offers thinking for the selection of the friction model in a study on rub-impact dynamics of shrouded blades.