中文摘要：

迷宫气封是大型旋转机械中的重要部件，其结构形式不但影响机组运行的经济性，还对机组运行的安全性有着重要的影响。本文以基于有限精确差分格式的非定常全三维粘性流场模拟技术为基础，采用κ-ε素流模型，分别研究了某超临界机组高压段动叶顶部气封齿在倾斜30°、60°、90°、120°和150°情形下迷宫气封的密封性；并将三维非定常密封流场与弹性转子作为一个系统，研究了不同倾斜角度下转子系统的稳定性，得到了一些对超临界及超超临界机组的设计具有重要参考价值的研究结果。

英文摘要：

Labyrinth gas seals are one of the important key parts in large rotating machinery, its structural form not only affects the airproof performance, but also have an important influence on the stability of machinery. An unsteady three-dimensional Navier-Stokes solver is used to study the airproof performance and rotordynamic stability of the labyrinth gas seals with 30°, 60°, 90°, 120° and 150° inclined teeth respectively. The basic time marching algorithm used to solve the fully 3D unsteady governing equations is known as a hybrid finite-analytic-difference scheme. The κ-ε model is chosen to model the turbulent components in the governing equations due to its widely acknowledged reputation. Some results which is of value to the design of super-critical steam turbine are obtained.