Radial Dynamics of Ultrasound-Driven Bubbles with Sensitivity Analysis on Liquid Physical Parameters

Ultrasonic bubbles exhibit radial dynamic behavior by absorbing ultrasonic energy, and this behavior depends on the specific excitation conditions and physical parameters of the liquid. In this study, the Keller–Miksis equation is applied to study the radial oscillations of bubbles, focusing on the absorbed ultrasonic energy. Furthermore, the sensitivity of bubble dynamics to physical parameters in liquids with varying viscosities is also investigated. The results demonstrate that the maximum oscillation radius, the rebound oscillation radius, the bubble collapse strength and the absorbed ultrasonic energy increase with ultrasonic pressure, while they decrease with ultrasonic frequency. Notably, with the exception of absorbed ultrasonic energy, the other three indicators exhibit an increasing–decreasing trend as the initial bubble radius increases. Additionally, liquids can be classified into low-viscosity and high-viscosity categories. The effect of liquid physical parameters on bubble collapse strength under different ultrasonic excitation conditions is complex and multifaceted. Overall, liquid viscosity is the most important factor influencing bubble collapse strength, whereas liquid density and surface tension also exert some influence under specific conditions. In contrast, ultrasonic speed has minimal impact on collapse strength.