ADAPTIVE MICROPHONE ARRAY TECHNIQUE FOR REMOTE MONITORING OF COMPONENTS IN NUCLEAR-POWER-PLANTS

Acoustic sensing technique provides an efficient measure to detect and diagnose incipient failures occurred in plant components. The study r eported here investigates the feasibility of adaptive super-directive microphone array technique for detection and localization of anomaly i n nuclear power plants. The technique extracts anomaly information of objective components from the acoustic signals obtained at geometrical ly arranged multiple microphones. A specific signal processing was use d to obtain a super-directive sensitivity of the microphone array and to adapt the sensitivity following the acoustic environmental change. Two adaptive sensing algorithms have been developed and implemented in a personal computer, and their abilities to extract the objective aco ustic signal have been tested through numerical simulation. For approp riate number of the microphones, the satisfactory performance of the s ound extraction has been obtained within reasonable computational load . The practical applicability of this technique to component monitorin g in nuclear power plants has been confirmed through the present study .