Dynamic analysis of finger seal using equivalent model based on distributed mass method

Abstract

Dynamic analysis of finger seal can be performed by finite element method or equivalent model based on lumped mass method now available, which is difficult in meeting both the acceptable calculation time and accuracy simultaneously. For this reason, interactions between finger elements are considered and the equivalent dynamic model based on distributed mass method is proposed in this article. Seal dynamic performances are obtained by using this model to calculate the equivalent parameters, air leakage flow, and the contact behavior between finger seal and the rotor. The work to be presented here concerns the mapping of dynamic behavior of the finger seal with a stack of three finger elements, including the dynamic displacement responses of finger elements, the leakage clearances, and the contact pressures between the finger elements and the rotor, as well as the leakage flow rate and the wear rate. The results calculated by the equivalent model presented in this study are evaluated by comparison with the published experimental data and results from the model based on lumped mass method, which shows that the equivalent model based on distributed mass method is far superior to that based on lumped mass method because the calculations are in good agreement with the experimental results.