Monitoring temperature and vibration in a long weak grating array with short-pulse generation using a compact...

Area of Science:

• Fiber optic sensing
• Photonics
• Instrumentation

Background:

• Accurate quasi-distributed temperature sensing and single-point vibration monitoring are crucial in various industrial applications.
• Traditional sensing methods may face limitations in spatial resolution, frequency response, or measurement accuracy.

Purpose of the Study:

• To develop and validate a novel quasi-distributed temperature and single-point vibration sensing system.
• To leverage ultrashort pulse interrogation of fiber Bragg gratings (FBG) for enhanced sensing capabilities.

Main Methods:

• Utilized ultrashort pulses from a gain-switching laser to interrogate an FBG array sensor.
• Implemented a fast data acquisition system to enable high-frequency dynamic measurements.
• Calibrated the system for temperature and strain measurements.

Main Results:

• Achieved quasi-distributed temperature sensing with a resolution of 1°C and sub-centimeter spatial resolution.
• Demonstrated single-point vibration sensing with a high-frequency limit of 245 kHz.
• Obtained a strain resolution as low as 1.2 µɛ for vibration detection.

Conclusions:

• The developed fast interrogation setup offers significant advantages for dynamic sensing applications.
• The FBG-based system provides a robust and accurate solution for simultaneous temperature and vibration monitoring.
• This approach enhances the capabilities of fiber optic sensors for high-performance measurements.