目前制约碰摩定量诊断的难题之一就是振动法无法对其进行有效定位.针对该问题,提出了一种适用于旋转机械的转静件碰摩故障定位的声发射(AE)波束形成方法.首先,根据旋转机械转静件碰摩力学模型和转子实验台参数建立了碰摩声发射的有限元仿真模型,进行了碰摩声发射仿真,分析了仿真信号特征和声发射波传播特性.然后,基于声发射仿真信号和声发射碰摩传播特性研究了几种典型的波束形成阵列形式(直线阵列、十字阵列和圆形阵列)的碰摩定位性能,确定直线阵列最适合用于碰摩定位;针对直线阵列的缺点,提出了传感器阵列布置的优化方案和定位流程.最后,通过实验对提出的碰摩故障定位方法进行验证.研究结果表明,通过选择正确的传感器阵列布置方式、合理的传感器阵列形式,声发射波束形成法可以实现对碰摩故障的准确定位.
One of the challenges restricted rubbing quantitative diagnosis is that vibration method cannot be effective applied to rubbing fault localization. Therefore,an acoustic emission( AE) beamforming array was presented to localize rotor-stator rubbing fault of rotating machinery. Firstly,finite element simulation model of rubbing AE was established based on mechanical model of rotor-stator rubbing and the structure of rotor test-bed,which can be used to simulate AE signals and study characteristics of simulating signals and AE wave propagation. Then rubbing localization performances of AE beamforming with typical arrays,such as line array,crossed array and circular array,were studied based on simulation AE signals and propagation characteristics of rubbing AE,and that the line array was the most appropriate for rubbing localization. Aiming to the shortage of line array,the improved sensor array and localization scheme were approached. Finally,the proposed localizing method of rubbing fault was verified by experiments. The results show that AE beamforming method can achieve accurate localization of rubbing fault by choosing the right sensor array and suitable sensor arrangement.