Real-time imaging of immersed fuel-sub assemblies using multi-channel ultrasonic camera

Area of Science:

• Nuclear Engineering
• Materials Science
• Non-Destructive Testing

Background:

• Fast breeder reactors (FBRs) require robust monitoring systems for fuel sub-assemblies (FSAs).
• High-temperature environments pose challenges for conventional imaging techniques.
• Real-time imaging is crucial for assessing structural integrity and operational parameters.

Purpose of the Study:

• To develop and evaluate a novel circular-array based real-time ultrasonic imaging technique for FSAs.
• To enable imaging of the FSA top-head region in high-temperature environments.
• To assess the growth and bowing of FSAs using ultrasonic data.

Main Methods:

• A circular-array ultrasonic camera system was designed and developed.
• An address-based analog multiplexing scheme was implemented for concurrent channel selection.
• Multi-channel ultrasonic data processing algorithms were developed for real-time analysis.
• An 18-channel ultrasonic camera system was experimentally evaluated.

Main Results:

• The developed system successfully provided real-time ultrasonic images of a dummy FSA in a water-immersed, elevated temperature environment.
• Qualitative visualization of the FSA top-head was achieved.
• Quantitative measurements of FSA top-head growth and bowing were successfully performed.

Conclusions:

• The circular-array based ultrasonic camera is a viable technique for real-time imaging of FSAs in high-temperature environments.
• The system demonstrates potential for monitoring structural changes like growth and bowing in FSAs.
• This technology can enhance the safety and operational efficiency of fast breeder reactors.