Characteristics of laser-induced bubbles in different surrounding pressures

The experimental system for research on laser-induced bubbles in different surrounding pressures was built. Bubbles were produced by pulsed laser focusing into water. A hydrophone was used to receive the acoustic signals produced by laser-induced bubble collapse. The pressure inside the tank was accurately controlled by an air pump. Characteristics of laser-induced bubbles and peak pressure of acoustic signals produced by laser-induced bubble collapse in different surrounding pressures were investigated through simulation and experiment. The results show that the movement period and maximum radius of laser-induced bubbles decrease as the surrounding pressure increases from 0.1 MPa to 0.7 MPa gradually. The peak pressure of acoustic signals produced by laser-induced bubble collapse increases as surrounding pressure increases between 0.1-0.4 MPa, and that decreases as surrounding pressure increases between 0.4-0.7MPa, the change speed of the former is larger than that of the latter.