ULTRASONIC TRANSDUCER ARRAY FOR STRUCTURAL INTENSITY MEASUREMENTS

Measurement of structural intensity, which is a vector quantity define d as an energy flow of vibration per unit area and is calculated from vibration velocity distribution, is a key technique for radiation nois e reduction and vibration control, An ultrasonic Doppler vibrometer ar ray is proposed for structural intensity measurement. A useful large a rray probe can be constructed. Since the ultrasonic system is much che aper than an optical one, and has no loading effect on specimens durin g measurement, in constant with conventional methods that use an accel erometer and a strain gauge, a system for 1-dimensional measurements i s made which is composed of ultrasonic transducers and an FM demodulat or. The validity of the proposed system is demonstrated experimentally by the 1-dimensional structural intensity measurement of a beam.