迷宫和薄叶气封结构与气动特性的对比分析

数值研究相同条件下迷宫气封和薄叶气封结构特点、气动特性、密封机理及密封效果，比较两种气封的差异。通过与已发表的试验数据的对比，校核所采用的商业计算流体力学软件CFX的可靠性，计算得到的性能曲线与试验数据有较好的一致性，采用的数值模拟方法可行。分别对迷宫气封和薄叶气封内部流场进行数值模拟。通过对两种气封计算结果的对比分析，阐明它们的密封机理，给出各自的封严特性和所产生的摩擦转矩的变化规律。分析结果表明，薄叶气封的径向间隙远小于迷宫气封，漏气量为迷宫气封的1/3，对旋转轴产生的摩擦阻抗力矩低于迷宫气封，从结构运行特点和气动性能两方面说明薄叶气封的优越性，认为在不久的将来薄叶气封有可能替代迷宫气封。

Comparative Analysis of Seal Structure and Aerodynamic Characteristics of Labyrinth and Leaf Seals

The structure feature, aerodynamic characteristics, sealing mechanisms and sealing effect of labyrinth seal and leaf seal are numerically studied under same condition, the difference of two kinds seals is compared. The reliability of commercial computational fluid dynamics computational code CFX is validated by using the experimental data from literature. The performance curves of computation has a good agreement with the experimental data, the numerical simulation method is feasible. Numerical simulation on the flow field of the labyrinth seal and leaf seal are carried out respectively by using the commercial software CFX. Through comparison analysis based on the calculation results of the two type seals, their sealing mechanisms is described, the sealing characteristics and the friction torque variation law of their own are given. The analysis results show that, the radial clearance of leaf seal is much smaller than the labyrinth seal, its leakage flow rate is about 1/3 labyrinth seals, and the friction resistance torque on the rotation axis is lower than the labyrinth seal. Because of the superiority of the leaf seals in structure operation characteristics and aerodynamic performance, leaf seals may replace labyrinth seals in the near future.