Cavitation Bubble Dynamics

Abstract

The basic problem in understanding bubble dynamics during the cavitation process is determining the pressure and velocity fields in the two-fluid medium along with the motion of the bubble wall under the influence of time-dependent (hydrodynamic, acoustic, or optical) pressure. In this chapter, differential equations describing the motion of a single cavity and a cluster of cavities are developed which indicate how the radius of a cavity (or cluster volume) varies with time. The basic physics of the problem is very complex. The complications arise from the following facts:

• The bubble interior is composed of both vapor and gas in an unknown ratio.

• Many energy losses are involved in damped oscillations of a cavity.

• A number of discontinuities, such as heat conduction, viscosity, compressibility, surface tension, mass transfer, diffusivity and temperature occur at the phase interface, and these have not been sufficiently quantified yet.