Study on the energy-focusing mechanism of spatial bubble clusters

Abstract

Cavitation research has important implications in fields such as mechanical drag reduction, material processing, and new medical device development. Bubble cluster formation, development, and collapse are critical steps in the cavitation process. High-precision numerical simulations have shown that the collapse of bubble clusters exhibits a characteristic energy focusing from the outside to the inside. This study proposes a focus-type model for the energy transfer in bubble clusters to analyze the formation mechanism of collapse pressure and improve the accuracy of quantitative predictions. The model comprises multiple bubbles (α) radiating energy and a bubble (β) receiving energy. Through numerical simulation, the energy transfer law during bubble interaction is studied, showing that relative energy transfer decreases as the dimensionless distance increases, which corresponds with the theoretical model. The study further analyses the relationship between energy transfer in basic and composite bubble cluster structures. Additionally, the study observed the pressure focusing effect of the bubble clusters and found a strong correlation between the focusing effect and dimensionless distance.