基于叶片应变测量的航空发动机风扇外物撞击监测识别

飞机在跑道上滑跑、起飞与着陆过程中的发动机外物撞击监测对其飞行安全保障至关重要。为监测识别发动机工作过程中的外物撞击事件,通过风扇叶片外物撞击模拟试验平台开展外物撞击模拟试验,采用应变测量的方法对叶片应力进行实时测量与分析,实现风扇外物撞击事件监测识别的目的。试验与分析结果表明：获取了数值模拟与应变测量的风扇转子叶片结构特性图,数值模拟与试验测量动频最大误差为0.86%;外物撞击使叶片的一阶动频幅值发生较大的增加,通过试验过程中的应变测点时频图可监测识别外物撞击事件发生的时刻、频次与位置等。

Foreign Object Impact Monitoring and Identification of Aero Engine Fan Based on Blade Strain Measurement

It is very important for aircraft flight safety to monitor the impact of engine objects in the process of taxiing, take-off and landing on the runway. In order to monitor and identify the impact events of external objects in the engine working process, the impact simulation test was carried out on the fan blade impact simulation test platform, and the stress of the blade was measured and analyzed in real time by the strain measurement method, so as to realize the monitoring and identification of the impact events of external objects of the fan. The experimental and analytical results show that the structural characteristics of fan rotor blades are obtained by numerical simulation and strain measurement, and the maximum error of dynamic frequency between numerical simulation and test is 0.86%. The first-order dynamic frequency amplitude of the blade increases greatly due to the impact of external objects. The time, frequency and location of the impact event can be monitored and identified through the time-frequency diagram of the strain measurement points in the test process.