Phase properties and interaction force of acoustically interacting bubbles; A Complementary study of the transition frequency

Ida, Masato

The transition frequencies of multibubble systems in a sound field are reexamined theoretically to confirm their existence and further clarify their physical properties. Via a forced coupled oscillator model, the following results are obtained: (1) further details of the characteristics of the transition frequencies, (2) the theoretical determination of the threshold distances for the appearance of the sub-transition frequencies, (3) a simple understanding of the sign reversal of the interaction force, and (4) the clarification of several similarities and differences among the natural, resonance, and transition frequencies in double-bubble cases. The present effort enforces our claim that transition frequencies causing no resonance response exist in multibubble systems and thoroughly clarifies the physical effects of the transition frequencies and their roles in the sign reversal of the interaction force.