混合/流体润滑状态振动信号统计学时域分析

Statistical Time Domain Analysis of Vibration Signals in Mixed/Fluid Lubrication States

为研究摩擦振动产生机制和特征,通过Stibeck曲线设计混合/流体润滑状态实验,对不同状态下振动信号进行统计学时域分析。结果表明:流体润滑状态下摩擦振动十分微弱,振动信号有效值不随载荷增加而增加,切线方向振动信号自相关函数变化平滑,法线和切线方向振动信号互相关函数相对比较圆滑;混合润滑状态下,振动信号有效值随载荷增加而增大,切线方向振动信号自相关函数和两方向振动信号互相关函数皆具有明显的冲击特性,通过测得信号相关函数可以提取出混合润滑状态下摩擦振动信号的冲击特性。对比分析测得振动信号统计学特征,可以识别2种润滑状态。

To study the mechanism and characteristics of friction vibration,mixed/fluid lubrication experiments were designed based on Stibeck curves,and the vibration signals under different conditions were analyzed in statistical time domain.The results show that under the condition of fluid lubrication,the frictional vibration is very weak,the root mean square(RMS)of vibration signal does not increase with the increase of load,the autocorrelation function of tangential vibration signal changes smoothly,and the cross-correlation function of normal and tangent vibration signals is relatively smooth.Under the condition of mixed lubrication,the RMS of vibration signal is increased with the increase of load.Both the tangential vibration signal autocorrelation function and the two-direction vibration signal cross-correlation function have obvious impact characteristics.Statistical characteristics of vibration signals measured by comparative analysis can identify two lubrication states.