Numerical investigation of nonlinear oscillations of two spherical gas bubbles in a compressible liquid

Abstract

This paper deals numerically with the nonlinear oscillations of two spherical gas bubbles interacting in a sound field. The nonlinear oscillations of the bubbles are investigated for different pressure amplitudes of the sound field and for different equilibrium radii of the bubbles. It is shown that the interaction effect becomes prominent in the frequency response curves of an initially smaller bubble; these curves are different from those of a single bubble. The harmonic resonance of the initially smaller bubble is more easily destroyed than that of the single bubble. The results also show that once one bubble begins the ultraharmonic oscillation, the second bubble also begins the ultraharmonic oscillation. This suggests that both bubbles can be the source of the first subharmonic component in the acoustic cavitation noise.