电涡流位移传感器测量模型及其在叶尖间隙测量中的空间滤波效应

Measurement Model and Tip Clearance′s Spatial Filtering Effect of Eddy Displacement Sensor

基于电涡流位移传感器测量原理,建立叶尖间隙的有限元模型.根据涡轮发动机等旋转叶片设备叶尖间隙的结构特征与测量需要,建立了具有矢量特性的叶片点阵模型.分析叶片厚度、叶片转速、传感器敏感区大小、信号采样速率引起的空间滤波效应,以及对叶尖间隙测量结果的影响.研究结果表明,一定叶片厚度情况下,叶片转速、传感器敏感区、信号采样速率存在最低要求,这一结论可为叶尖间隙测量系统设计提供重要理论依据.

The tip clearance measurement model is established by measurement principle of the eddy displacement sensor.According to structural characteristics and measurement needs of tip clearance of turbine engine and other rotating blade device,a leaf lattice model with vector characteristics is established.The effect of spatial filtering and the value of tip clearance measurement,caused by blade thickness,sensing zone size,blade rotation speed and signal sampling rate has been analyzed.The result shows that there is a minimum requirement about sensing zone size,blade rotation speed and signal sampling rate on the condition of certain blade thickness.The conclusion provides an important theoretical basis for the design of the tip clearance measurement system.