Self-Induced Transparency and Frequency Conversion Effects for Acoustic Waves in Water Containing Gas Bubbles

Abstract

The presence of gas bubbles exerts a great influence on nonlinear acoustic properties of a liquid. Theoretical estimations [1–3] as well as experimental observations of shock wave and soliton formationin acoustic impulses [1, 2] have indicated the increase of the dominant nonlinear parameters by several orders of magnitude due to the presence of bubbles. In most cases, however, the spectra of the acoustic signals lie below the bubble resonance frequencies. At the same time the nonlinear resonance effects become more intense and complicated. In most real situations the bubble sizes are widely distributed and nonlinear effects are most essentially influenced by those bubbles whose resonance frequencies correspond to the spectrum of the acousticsignal. Such resonance nonlinearities have not yet been investigated beyond theoretical calculationsof a medium with monoradial bubbles.