Passive movement characteristics analysis and collision risk assessment of floating ring seals of aero-engine

Research on floating ring seals of an Aero-engine, the equivalent analysis model of the dynamic characteristics was established which considering the dynamic response of the rotor, the sealing clearance, the gas buoyancy of the main sealing surface and the elasticity of the wave spring. Minimum radial distance between the graphite ring component and the rotating ring was evaluated. The results showed that the minimum radial distance of the high-pressure side of the two-stage floating ring seal was 0.027 mm, the minimum radial distance of the low-pressure side of the two-stage floating ring seal was 0.164 mm, and the minimum radial distance of the single-stage floating ring seal was 0.026 mm. The influence of friction coefficient of auxiliary sealing surface, processing error and assembly error of wave spring on the passive movement characteristics of floating ring seal was analyzed.The results showed that the risk of collision between the floating ring seal and the rotating ring was controllable when the auxiliary sealing surface of the floating ring seal has good machining accuracy and lubrication condition.