篦齿封严结构高速旋转碰磨实验研究

Experimental study on high-speed rotation and rubbing of labyrinth seal structure

针对压气机铜银锌封严环在航空发动机转子高速旋转过程中与篦齿之间发生的碰磨现象,利用最高转速45000 r/min的高速旋转实验台进行实验研究,得到了封严环碰磨区域的表面形貌以及磨损槽尺寸,并获得了封严环初始温度、篦齿径向侵入深度对封严环碰磨区域径向与轴向温度分布以及碰磨力的影响规律。实验结果表明:在篦齿径向侵入速率V_(r)≥0.04 m/s时,碰磨过程中铜银锌涂层会发生塑性变形,在磨损槽两侧产生毛刺;碰磨过程中封严环碰磨区域温度会急剧升高,距封严环内壁面径向距离越近的位置温度越高,但在同一径向距离的不同轴向位置温度基本接近;碰磨力和温升随封严环初始温度的升高而减小,而篦齿径向侵入深度的增加则导致碰磨力和温升增大;相同工况条件下,篦齿径向侵入时的碰磨力和温升变化要比轴向侵入时更剧烈,碰磨产生的径向力显著大于轴向力。

Aiming at the rubbing phenomenon between the copper-silver-zinc seal ring of the compressor and the labyrinth during the high-speed rotation of the aeroengine rotor,an experimental study was carried out on a high-speed rotation test bench with a maximum speed of 45000 r/min.The surface morphology and rub-grooves size of the seal ring rubbing area were obtained,and the effect of the initial temperature of the seal ring and the radial intrusion depth of the labyrinth on the radial and axial temperature distribution and rubbing forces in the seal ring rubbing area was obtained.When the radial intrusion rate of the labyrinth V_(r)≥0.04 m/s,the plastic deformation of the copper-silver-zinc coating occurs during the rubbing process,and burrs are generated on both sides of the rub-grooves.During the rubbing process,the temperature in the rubbing area of the seal ring will rise sharply;the closer the radial distance from the inner wall surface of the seal ring,the higher the temperature;the temperature at different axial positions with the same radial distance is basically the same.The rubbing forces and temperature rise decrease with the increase of the initial temperature of the seal ring,while the increase of the radial intrusion depth of the labyrinth leads to the increase of the rubbing forces and temperature rise.Under the same experimental conditions,the rubbing forces and temperature rise in the radial intrusion process of labyrinth change more violently than that in the axial intrusion process,and the radial force generated by friction is significantly greater than the axial force.