Health Monitoring of Engine Blades By Using an In-Line Fiber-Optic F-P Strain Sensor Based on Hollow-Core Photonic Crystal Fiber

摘要

We present the application of a fiber-optic F-P strain sensor based on hollow-core photonic crystal fiber (HCPCF) to measurement of stress of engine blades. The blade stress under different rotating speeds is tested by detecting the reflected wavelength shift of the HCPCF sensor. The experimental results show that the strain has a quadratic relationship with the rotating speed, which agrees well with the theoretical analysis. As such a HCPCF sensor withshort cavity length can stand high temperature of up to 600°C and has low temperature sensitivity, it would be possible to realize real-time health monitoring of engine blades during operation.