无转速同步条件下转子叶片非接触振动测试方法研究

Experimental investigation of non-contact vibration measurement of rotor blade without once-per-revolution sensor

针对非接触振动测试系统中转速基准信号无法安装或容易失效的问题,提出了无转速同步条件下的转子叶片非接触振动测试方法,利用光纤传感器测试叶片脉冲信号实现振动识别和转速获取。在临界转速试验器上,进行了无转速同步条件下的模拟转子叶片非接触振动测试,并将测试结果分别与应变片测试结果、光纤传感器实现转速同步的叶片非接触振动测试系统测试结果进行了对比分析。结果表明:无转速同步条件下的非接触振动测试系统能实现转子叶片振动测试,且在叶片一弯振型下所得结果误差较小。此研究成果将在航空发动机整机、核心机的高压压气机和涡轮转子叶片非接触振动测试中发挥重要作用。

For the non-contact vibration system, it is difficult to set baseline signals of rotating speed and the signals are easily to fail. By utilizing the pulse signal of the optical sensor, a non-contact vibration measurement method of rotor blades that does not require a once-per-revolution(OPR) is proposed, and both the vibration information and rotating speed of the rotor blades can be obtained. The vibration measurements of simulating rotor blades have been done without one-per-revolution. The results have been compared with the dynamic strain results from the traditional strain gage and the vibration results that depend on the once-per-revolution. The comparison results demonstrate that the non-contact vibration measurement system can depend on once-per-revolution, where the measurement accuracy can be guaranteed under first flap mode. This study will play an important role in the non-contact vibration of rotor blades in the whole aero-engine and the core engine.