半球面螺旋槽动静压气体轴承运行稳定性研究

Study on Motion Stability of the Hemisphere Spiral Groove Hybrid Gas Bearings

针对高速动静压气体轴承气膜的复杂非线性动力学行为,搭建半球面螺旋槽动静压气体轴承转子试验台,以试验数据为基础,结合小扰动理论,对系统动态特性进行线性化分析,建立轴承转子系统动力学和运动学模型,构建基于振动数据的瞬态刚度阻尼计算方法,结合滑动平均法分析不同转速情况下转子偏心量、供气压力对轴承动态特性系数的影响规律。结果表明:随着偏心量的增大气膜刚度和阻尼均有不同程度的增加;随着转速升高刚度持续增大,在31000r/min时先减小后趋于稳定、阻尼则呈线性增大趋势;随着供气压力的增大气膜刚度增大,阻尼则先升高后趋于稳定;供气压力在0.6MPa,偏心量为52μm,转速设定为31000r/min时可以保证较大刚度和阻尼,同时具有良好的稳定性。

Aimed at the complex nonlinear dynamic behavior of high-speed hydrostatic gas bearing,build the experimental de⁃vice for spherical spiral groove gas bearing,combine the perturbation theory,linearize the dynamic characteristics of the system,establish the dynamic and kinematic models of bearing rotor system,constructed a transient stiffness damping calculation meth⁃od based on vibration data,combine with the sliding average method,analysis the influence of different conditions on bearing dynamic characteristics.The results show that the stiffness and damping increase with the increase of eccentricity;the stiffness in⁃crease with the increase of rotational speed,at 31000r/min,the damping decreases first and then tends to be stable and the damp⁃ing increases linearly;with the increase of air supply pressure,the film stiffness increases rapidly,and the damping increases first and then tends to be stable;the great stiffness and damping be got when the air supply pressure is at 0.6MPa,the eccentricity is at 52μm,and the rotation speed is set at 31000r/min,and the system has good stability.