Numerical simulations of an acoustically-driven bubble near a wall: analysis of the growth and collapse with standoff distance

A high-order accurate, fully compressible, multiphase model is used to simulate the acoustically-driven growth and collapse of a gas bubble in water. The model is used to investigate the growth of a near wall bubble and the subsequent collapse when the bubble is positioned in an acoustic field. The growth phase of the near wall bubble is studied: the influences of the wall and the acoustic field are investigated. The near wall is found to significantly restrict the growth of the bubble, with decreasing influence as the bubble standoff distance from the wall is increased. The variation in the standing pressure wave of the acoustic field is also found to be an important consideration, as a reduction in the acoustic driving pressure results in less bubble growth and subsequently a less violent collapse.

The model is compared to the previously developed models that are able to capture the collapse of a near wall bubble, (1) the Rayleigh growth and collapse and (2) the Rayleigh-Plesset (RP) initialized collapse model, highlighting the limitations of the previously developed models.