直通式篦齿密封性能的数值模拟与试验研究

Numerical Simulation and Experimental Study on Straight Labyrinth Seal

利用FLUENT软件对过热蒸汽分级机转轴的篦齿密封的内部流场进行数值模拟,对影响其性能的部分因素进行分析。结果表明,篦齿密封两端压差对泄漏量的影响非常明显,压差越大,泄漏量越大;篦齿密封的泄漏量随着节流间隙宽度增大而增大,但两者是非线性的关系;在齿形角不变的情况下,篦齿空腔深度小于2 mm时对密封泄漏量的影响很大,而空腔深度大于2 mm时对密封泄漏量的影响很小;转轴转速对泄漏量基本没有影响。通过试验验证了数值模拟方法计算篦齿密封泄漏量的可行性。

The internal flow of the straight labyrinth seal of superheated steam classifier rotor shaft was numerically sim- ulated by software FLUENT, and parts of the effect factors on straight labyrinth seal were studied. The results show that the leakage of labyrinth seal is obviously impacted by the pressure differential, and it is increased with the increase of pressure differential. The leakage of labyrinth seal is increased with the increase of the throttle gap width, but the relation is non-lin- er. Under the condition of the tooth profile angle is constant, the labyrinth seal cavity depth has great influence on the leak- age when it is less than 2 mm, and has little influence on the leakage when it is more than 2 mm. The speed of the rotating shaft has no influence on the leakage. The feasibility to calculating the leakage of labyrinth seal with numerical simulation method was validated by the experiments.