梳齿密封直接刚度系数实验识别

Experimental Identification for Direct Stiffness Coefficient of the Labyrinth Seal

设计并搭建梳齿密封直接刚度系数识别实验装置,研究了不同转速下激振频率和进口压力对密封直接刚度系数的影响,并与DyRoBeS中的Bulk Flow模型理论计算结果进行对比。结果表明:在任意工况下,所测的梳齿密封直接刚度系数均为负值,易出现转子不稳定现象;直接刚度系数随着转速、进口压力和激振频率增大而减小,转速对直接刚度系数的影响较小,且直接刚度系数与高频激振频率相关性较强;DyRoBeS理论计算与实验结果吻合较好。

A test rig for identification of the direct stiffness coefficient of the labyrinth seal was designed and built.The influence of the excitation frequency and inlet pressure on the direct stiffness coefficient at different rotational speeds was studied.The experimental results were compared with the theoretical calculation of the Bulk Flow model in DyRoBeS.Results show that the direct stffness coefficient of the labyrinth seal is negative under any operating conditions,which makes it prone to rotor instability.The direct stiffness coefficient decreases with increasing rotational speed,inlet pressure and excitation frequency.The rotational speed has little influence on the direct stiffness coefficient.And the direct stiffness coefficient is highly dependent on the high excitation frequency.The theoretical prediction calculation of DyRoBeS shows good agreement with the experimental measurements.