Abstract：The magnetostriction-induced ultrasonic cavitation flow was numerically simulated by using “Singhal full cavitation model” and the dynamic mesh technique. The computational results show that cavitation occurs at the local flow field proximity to the specimen and the specimen is subjected to impact of impulse pressure due to high frequency vibration of specimen. Pressure and vapor volume fraction (VVF) are annularly distributed around the center on the specimen, which vary periodically with vibration. Bubbles collapse after twice oscillation on the center region of specimen, which results in intense impulse pressure that can reach about 5MPa. Impulse pressure forms on the interval annular zones and alternately occurs on the adjacent annular zones with vibration cycle. Acoustic pressure quickly attenuates with ultrasonic propagation in the ultrasonic cavitation flow field. The considerable fluctuation of pressure occurs within the distance of 20mm to the end of ultrasonic solid horn. The impulse pressure is promoted on the central region of specimen as the vibration amplitude is increased from 25μm to 30μm. When the vibration amplitude is further increased to 35μm, the effect of cavitation is further enhanced, but the impulse pressure is diminished on the central region of specimen.
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