STRUCTURAL DAMAGE ANALYSIS AND STRENGTH DESIGN OF ELASTIC RING SQUEEZE FILM DAMPER

Elastic ring squeeze film damper (ERSFD) is a compact support structure used in rotary machinery and encompasses highly efficient damping for vibration attenuation of the rotor system. The cyclic load produced by whirling motion of the rotor may lead to damage, performance degradation, and failure of the ERSFD. Design measures are thus required for safe operation of the ERSFD and the rotor system. This paper delves into the potential damage mechanisms affecting the elastic ring based on structural and mechanical principles. A Finite Element Method (FEM) model considering the contact effect of elastic ring bosses is established. Numerical analysis is conducted to analyse structural deformation, stress distribution, friction at boss interfaces, and damage to the U-shaped hole. The influence of structural parameters on these aspects is investigated, and strength design strategies are derived. Findings indicate that deformation in the elastic ring causes stress concentration at the transition fillets of the bosses, which can be reduced by increasing the curvature radius. The contact state at the boss interfaces tends to produce line contact at the edges, leading to increased contact pressure and friction stress, potentially causing interface damage. Implementing a pin in one boss of the ring is shown to significantly reduce contact surface damage compared to other configurations. These results provide important insights for the design of the elastic ring in ERSFDs.