转子振动对T型交错式迷宫密封性能影响

Effects of Rotor Vibration on T Type Labyrinth Seal Performance

关键词:  T型交错式迷宫密封  转子振动  泄漏  气体作用力

Key words:  T type labyrinth seal  Rotor vibration  Leakage  Aerodynamic force

摘要:

为了改善传统交错式迷宫密封容易产生气流激振并导致转子失稳，对密封结构进行改造，提出了一种可以平衡气流激振力的T型交错式迷宫密封。考虑转子振动，三种转速(18，24与30kr/min)以及三种压差(0.2，0.3与0.4MPa)，对直通式、交错式迷宫密封以及T型交错式迷宫密封进行数值计算。结果表明，在相同齿顶间隙的条件下，交错式迷宫密封的泄漏量较T型交错式迷宫密封减小约8% 较直通式迷宫密封减小约32%。通过对比三种密封流场所产生的气体作用力之间的差异，得出T型交错式迷宫密封的优势在于扩大了Lomakin效应，增强了交错式迷宫密封的稳定性，同时实现了高封严效率与较高稳定性。

Abstract:

To improve the performance of the interlaced labyrinth seal，which easily causes gas excitation and rotor stability loss，a new type of labyrinth seal named T type labyrinth seal is redesigned for balancing the exciting force on rotor. Under rotor vibration，straight-through，conventional interlaced，and T type interlaced labyrinth seal were compared and analyzed under three rotor speed(18，24 and 30kr/min) and pressure differences (0.2，0.3，and 0.4MPa). With same tip clearance，leakage of interlaced labyrinth seal is approximately 8% less than that of the T type labyrinth seal，which is approximately 32% less than straight-through labyrinth seal. By comparing the aerodynamic forces，the advantage of the T type labyrinth seal is to enlarge the Lomakin effect，improving the stability of conventional interlaced labyrinth seal，and excellent seal efficacy and higher stability can be achieved synchronously in T type labyrinth seal.