Theoretical and experimental study on micron-sized SiC micro-abrasives regulating ultrasonic cavitation intensity

Ultrasonic cavitation technology has shown significant advantages across scientific and engineering fields, where cavitation intensity is critical to its performance. However, strategies for precisely regulating cavitation intensity remain underexplored. This study addresses this gap by introducing micron-sized silicon carbide (SiC) micro-abrasives into the medium to adjust cavitation intensity. A mathematical model was developed to predict the influence of micro-abrasives on cavitation by modifying nucleation rates, fluid viscosity, and pressure fluctuations. Experiments were conducted to evaluate the effects of ultrasonic frequency, micro-abrasive particle size, and mass fraction on cavitation intensity. Fluorescence analysis revealed that adding SiC micro-abrasives significantly enhanced fluorescence intensity, indicating increased cavitation. At ultrasonic frequencies of 20, 30, and 40 kHz, fluorescence intensities increased from 197.4, 142.2, and 99.2 to 248.3, 190.7, and 140.1, respectively, demonstrating that lower frequencies produce higher cavitation intensity. When adding SiC micro-abrasives with particle sizes of 6.5, 13.4, and 34.7 μm, fluorescence intensities were 190.7, 164.6, and 157.4, respectively, showing a negative correlation between particle size and cavitation intensity. As the mass fraction of SiC increased from 0.5 % to 15 %, fluorescence intensity initially surged, then slightly decreased and stabilized. At a 5 % mass fraction, the enhancement was optimal, with fluorescence intensity increasing from 142.2 to 284.9. The experimental results aligned well with the theoretical predictions, confirming the model's accuracy. This study underscores the effectiveness of SiC micro-abrasives in enhancing cavitation intensity, offering scalable insights for optimizing ultrasonic cavitation in industrial applications.