用于高速转轴径向振动检测的光纤传感技术

Fiber sensor used in detecting radial vibration of high rotating speed shaft

采用光纤测量技术实现航空叶轮泵高速转轴径向振动的检测,对检测系统的工作原理做了详细介绍。设计了新型的光纤测头,提出相应的补偿方案,并对补偿机理进行了详细的分析。对测试系统的特性进行了研究,得出位移特性调制函数表达式,给出了仿真曲线。理论计算和仿真分析表明,该测试系统能有效地消除因光源光强波动、光纤弯曲损耗、表面反射率等因素对输出特性的影响,可以在叶轮泵内部电磁干扰严重和高温等恶劣环境下实现对高速转轴径向振动的检测。实验测试结果表明,随着转轴转速由1 000 r/min提高到10 000 r/min,径向振动幅值单调增加,这与实际情况相符合。

Optical fiber measuring technique is adopted to detect radial vibration of a high speed rotating shaft in aerial impeller pump and the principle of the detecting system is introduced in detail in this paper. A new type fiber gauge head has been developed, and relevanted compensatory approach is given. Also, the displacement characteristic modulating function is educed and the emulator curve is provided through studying of the system. Experimental results show that .the system can eliminate the infection from light intensity fluctuation, fiber flexural loss and surface reflection index and detect the radial vibration of high speed rotating shaft in aerial impeller pump under the surrounding of strong electromagnetic interference and high temperature. Experiments also show that amplitude of radial vibration increases monotonously with rotation speed of the shaft ranging from 1000p r/min to 10 000 r/ min, it agrees with the physical situation.