Acoustic bubbles have wide and important applications in ultrasonic cleaning, sonochemistry and medical ultrasonics. A two-microbubble system (TMS) under ultrasonic wave excitation is explored in the present study, by using the boundary element method (BEM) based on the potential flow theory. A parametric study of the behaviour of a TMS has been carried out in terms of the amplitude and direction of ultrasound as well as the sizes and separation distance of the two bubbles. Three regimes of the dynamic behaviour of the TMS have been identified in terms of the pressure amplitude of the ultrasonic wave. When subject to a strong wave with the pressure amplitude of 1atm or larger, the two microbubbles become non-spherical during the first cycle of oscillation, with two counter liquid jets formed. When subject to a weak wave with the pressure amplitude of less than 0.5atm, two microbubbles may be attracted, repelled, or translate along the wave direction with periodic stable separation distance, depending on their size ratio. However, for the TMS under moderate waves, bubbles undergo both non-spherical oscillation and translation as well as liquid jet rebounding.

声气泡在超声清洗，声化学和医学超声中具有广泛而重要的应用。通过基于势流理论的边界元方法（BEM），研究了超声波激发下的两微泡系统（TMS）。根据超声波的振幅和方向以及两个气泡的大小和分离距离，对TMS的行为进行了参数研究。根据超声波的压力幅度，已经确定了TMS动态行为的三种状态。当受到压力波为1atm或更大的强波时，两个微气泡在第一个振荡周期内变为非球形，并形成两个反向液体射流。当受到压力振幅小于0.5atm的弱波作用时，两个微气泡可能会以其周期性的稳定间隔距离沿波向被吸引，排斥或平移，具体取决于它们的尺寸比。但是，对于中等波浪下的TMS，气泡会经历非球面振荡和平移以及液体射流回弹。