煤矿通风压缩机转子系统临界转速计算

Calculation of Critical Speed of Rotor System of Ventilation Compressor in Coal Mine

压缩机转子系统临界转速确定是研究其工作稳定性的重要前提,支撑刚度是影响临界转速的重要因素。在考虑浮环轴承内、外油膜刚度的情况下,建立浮环轴承参数化模型,并计算获取了浮环轴承非线性耦合等效刚度;在此基础上,利用DyRoBeS软件建立压缩机浮环-转子系统模型,分析了转子系统的临界转速并通过试验验证了该计算方法正确性。结果表明:轴承内、外油膜的非线性等效刚度系数均随转速的增大而减小,增加浮环后转子在工作转速下的衰减率分别提高了20.1%,浮环轴承能有效地提高转子的静稳定性。

The calculation of critical speed of the compressor rotor system is an important research subject of work stability problem. Support stiffness is an important factor affecting critical speed, in the case of considering the coupled stiffness of internal and external oil film stiffness. Bearing parametric model of floating ring bearing was established and oil film dynamic stiffness was calculated;on this basis the establishment of the compressor rotor system model has been done by using DyRoBeS software, critical speed of the rotor was calculated and was validated by the test. The results show that the coefficients of the nonlinear equivalent stiffness of the bearing oil film decreases with the increase of the rotational speed, the attenuation rate of floating ring rotor compressor end increase by 20.1% in work speed, floating ring bearing can effectively improve the stability of working process of rotor.