Preliminary test results and status of acoustic leak detector development in the US

The US has an extensive technology in the general area of acoustic surveillance. High temperature in-sodium microphones, in-vessel waveguides, and data analysis techniques have been successfully demonstrated in national development programs. This technology has been applied specifically to the development of an acoustic leak detection/location monitor for small leaks in an operating steam generator. Advanced cross-correlation signal processing techniques, coupled with either vessel mounted accelerometers or in-sodium waveguide/transducer microphone arrays, is believed to be the most promising direction for further development of such monitors. Development of signal analysis software and feasibility experiments leading to a conceptual acoustic leak detection scheme have been made. This acoustic detector has the potential for both detection and location of small leaks within short times. Careful attention has been paid to achieving effective operator interfacing. Leak detection/location has been demonstrated in nonboiling geometric models simulating the steam generator, and small sodium-water reactions have been monitored in laboratory test rigs.