A new vector velocimetry by real time ultrasonic imaging using M-sequence encoding array transducer

In order to measure velocity vector of moving object in water, we have developed a new vector velocimetry using ultrasound. Velocity vector was measured by real-time ultrasonic imaging using M-sequence encoding array transducer. When this array transducer was applied to ultrasonic imaging, a cross section image was obtained by a transmitting and receiving process. In experiment, we tried to measure the two dimensional velocity vector of a wire target moving at a constant velocity of 10.0 mm/s and at a constant angle of 45° away from the transducer surface. An ultrasonic pulse was transmitted with a constant interval time of 10.0 ms, and We obtained ultrasonic images of 16. The system was operated at the frequency of 2.5 MHz. Images at each acquisition were reconstructed by correlation method. The velocity vector was calculated by the trajectory of target in each image. In conclusion, it was found that the velocity vector of the target be measured with accuracy 4% by the developed vector velocimetry