发动机涡轮转子叶片叶尖定时信号干扰与抑制

Interference and suppression of tip-timing signal of engine turbine rotor blade

介绍转子叶片叶尖定时非接触测量原理及光纤传感器工作特点。将带冷却的光纤传感器应用于发动机涡轮转子叶片振动测试,获取高温高转速叶尖定时信号。结果显示,转速大于12513 r/min(叶片测试位置工作温度1326 K)时,脉冲信号出现严重干扰,系统无法完成阈值触发和到达时间计时。分析干扰产生原因,提出降低干扰的滤波和蓝光发射方法,开展发动机涡轮转子叶片非接触测振试验,结果表明:滤波仅能够抑制红光辐射,12513 r/min以上信号干扰有所改善,12605 r/min(叶片测试位置工作温度1375 K)以上仍存在干扰;滤波结合蓝光发射能有效解决高温高转速下的干扰问题,12702 r/min(叶片测试位置工作温度1388 K)以下,叶尖定时信号脉冲波形较好,系统可有效实现阈值触发和到达时间计时。

The non-contact measurement principle of rotor blade tip timing and the working characteristics of optical fiber timing sensor were introduced.The optical fiber sensor with cooling was applied to the vibration test of engine turbine rotor blade to obtain the blade tip timing pulse signal under high temperature and high rotational speed.The results showed that when the rotational speed was greater than 12513 r/min(working temperature at the blade testing position was 1326 K),the pulse signal had serious interference,and the system cannot trigger the threshold and record the time of arrival.The causes of interference signal were analyzed,and the solutions of filtering and blue light emission to reduce signal interference were provided.The non-contact vibration test of engine turbine rotor blade was carried out to verify the proposed method.The results showed that the red light radiation can be suppressed only by filtering,and the signal interference above 12513 r/min was improved,but the interference still existed when the rotational speed exceeded 12605 r/min(working temperature at blade testing position was 1375 K);the combination of blue light emission and filtering can effectively solve the interference problem under high temperature and high rotational speed.Below 12702 r/min(working temperature of blade testing position was 1388 K),the pulse waveform of blade tip timing signal was good,and the system allowed for effective triggering and timing.