迷宫与蜂窝密封的流场及动力学性能分析

Analysis on Flow and Aerodynamic Performance of Labyrinth and Honeycomb Seals

为了研究转子振动与转子密封之间的相互作用及影响,本文对两种环形转子密封的流动特性以及其所对应的转子的动力学特性进行了数值计算。首先提出了一种计算转子动力学参数的数值方法,可以求解转子的振幅和振频。之后这些参数可以作为非稳态条件应用于流体数值计算中。数值分析的结果表明,转子的振动能够降低密封的性能并且引起额外的转子气体力。通过深入的分析证实了该气体力总是趋向于降低转子的自激振动,并且随着压差的增大这种效应更加明显。关于上述现象在两种转子密封中的异同在本文中给出了说明。最终得出结论:适当结构的迷宫、蜂窝密封或者其二者的组合是完全有可能降低转子自激振动带来的负面影响的。

For research the relationship between rotor and seals, both rotor dynamics and flow characteristics are computed for two types of seals, honeycomb and labyrinth seals in this paper. Authors present a method to compute rotor dynamics parameters. By this method, amplitude and frequency of vibration can be solved. Then these parameters are used for unsteady fluid flow computation. The numerical results indicate that the rotor vibration can reduce sealing performance and arouse additional aerodynamic force on rotor. By further analysis, the aerodynamic force is tending to reduce the self-excited vibration of rotor, and this effect becomes more apparent with the increase of pressure difference. The difference effects between the two types of seals are presented in this paper. Finally, we conclude that the suitable structures of honeycomb seal and labyrinth seal, or their combination can minimize the adverse impact on rotor vibration.