A DEVICE FOR UNDER SODIUM VIEWING

THE CONTINUED PROGRESS BEING MADE IN LIQUID-METAL-COOLED NUCLEAR REACTORS REQUIRES A CAPABILITY TO MONITOR AND INSPECT REACTOR INTERNALS. SINCE THE 1960S RESEARCH IN ULTRASONIC IMAGING HAS BEEN PURSUED AT A SOMEWHAT LEISURELY PACE. SIMPLE SONIC ECHO RANGING HAS BEEN THE PRINCIPLE RELIED UPON TO GENERATE IMAGES OF INTERNALS. THIS REQUIRES A PRECISE MECHANICAL MEANS TO SCAN THE ULTRASONIC BEAM OVER THE OBJECT TO BE IMAGED. THIS PROJECT CONSIDERS AN ALTERNATIVE, A DEVICE WITH NO MOVING PARTS OTHER THAN AN ARM FOR AIMING IT. THIS DEVICE WILL CONSIST OF A CIRCULAR ARRAY OF ULTRASONIC ELEMENTS, EACH PRODUCING A DIVERGING CONE OF SOUND. THESE ELEMENTS WILL BE ENERGIZED BY A FREQUENCY-SWEPT SIGNAL, AND THE ECHO RETURNS WILL BE USED TOSYNTHESIZE A RADIAL ARRAY EXTENDING FROM EACH ELEMENT TO THECENTER. THIS FILLED DATA ARRAY WILL THEN BE USED TO RECONSTRUCT A THREE-DIMENSIONAL IMAGE OF THE OBJECT'S SURFACE.