Cavitation bubble growth near an elastic object

Gas bubbles cavitate near and erode small urinary stones during focused-ultrasound therapies. During the treatment, the bubbles oscillate due to the compressive and tensile ultrasound pressures or are attached to the stone, collapse, and impinge on its surface. During bubble oscillations, the liquid evaporates into the gas bubble, water vapor condenses, and non-condensable gases dissolve into the liquid. We conduct 3D simulations of a cavitating bubble rapidly growing near a rigid wall using the open-source Multi-component Flow Code [Bryngelson et al. Comp. Phys. Comm. (2021)]. MFC solves the 3D, compressible Navier--Stokes equations using a six-equation multiphase numerical model, including a phase change model. The solver is verified against the spherical bubble dynamics theory, including phase change. Simulations show wall-attached cavitation from the wall-reflected rarefaction of a nearby exploding water vapor-gas bubble. We also examine an ultrasound-induced oscillating bubble near an elastic object. Maximum pressures and stresses in the object for varying driving pressure, frequency, and bubble stand-off distances are presented.