Abstract: To clarify the cavitation behavior of ultrasonic in the slag system， the Rayleigh-Plesset equation was applied to simulate the motion behavior of cavitation bubbles in the 25% K₂O-30% Na₂O-45% SiO₂ slag at 1020℃. The results show that at the cavitation nucleus of 15μm and the sound pressure of 3.039MPa， the cavitation bubbles change from one oscillation collapse to transient cavitation with multiple oscillations before collapse at 25kHz， to acyclic steady-state cavitation at 36kHz， and to periodic steady-state cavitation at 63kHz， showing an overall decrease in vibration amplitude and increase in collapse time. At cavitation nucleus of 15μm and frequency of 20kHz， the cavitation bubble changes from steady-state cavitation to one-oscillation collapse transient cavitation at 2.4MPa， to two-oscillation collapse transient cavitation at 17MPa， and to multi-oscillation collapse transient cavitation at 170MPa， showing an overall increase in vibration amplitude and collapse time. At sound pressure of 3.039MPa and frequency of 20kHz， the cavitation bubble changed from periodic steady-state cavitation to one-oscillation collapse transient cavitation at 2μm， then to multi-oscillation collapse transient cavitation at 21μm， and finally to acyclic steady-state cavitation at 33μm， showing an overall decrease in vibration amplitude and an increase in collapse time.

Key words: metallurgical slag; ultrasound; cavitation; numerical simulation