Contact Force Analysis of a Rotor-Brush Seal System With Eccentricity and Airflow

The mechanics properties of brush seals are usually very complicated. Here, the contact force of a rotor-brush seal system was analyzed based on the bending deformation theory considering the interaction of eccentricity and flow induced force. The seal force expression was established by using the Bernoulli–Euler beam equation and superposition method, and the effects of eccentricity, friction coefficient, bristle lay angle, and uniform force of flow on the acting force of rotor system was analyzed. An experimental test rig of a Stodola–Green rotor-brush seal system was set up, and the effect of seal force on vibration characteristics of the rotor system was evaluated by the experiment. The results showed that with a flow induced force, the contact force of the rotor decreases with the increase of eccentricity. The contact force increased with the increase of flow induced force as well. The theoretical results were in accordance with the experimental results and, thus, validate the seal force of the brush seal.