The Influence of Characteristics of Thermodynamic Effect and Bulk Viscosity Effect on the Bubble Dynamics

摘要

The important influence of thermodynamic effect inside bubble and viscous liquid volume outside the bubble on the dynamics of bubble can be found. However, the combined effect of those two factors has currently little research and the thermodynamic effect of the bubble can be seen from the Flynn model. Taking thermodynamic effect inside bubble and viscous liquid volume outside bubble into consideration, the Flynn model can be revised under ultrasonic excitation. The effect of ultrasonic frequency, ultrasonic amplitude and the initial bubble radius on the dynamics of the bubble can be simulated numerically. For comparison with Flynn model, the chaotic and bifurcation diagram of the revised model can be obtained. It can be seen that the thermodynamic effect can extend the time in the stable states, and viscous liquid volume can restrain the random motion of the bubble. To achieve obvious cavitation effect, a higher intensity ultrasonic excitation can be required which the motion of the bubble can be from bifurcation into chaotic. The results solve the problem that the Flynn model not fits the bubble movement well actually. It is provided a theoretical basis for the potential application of the cavitation effect.