Modeling acoustic cavitation with inhomogeneous polydisperse bubble population on a large scale

Area of Science:

• Fluid Dynamics
• Acoustics
• Computational Physics

Background:

• Acoustic cavitation is a complex phenomenon involving bubble dynamics under acoustic fields.
• Simulating large-scale acoustic cavitation flows with polydisperse bubble populations presents significant computational challenges.
• Existing models often struggle with large geometries and varying bubble sizes.

Purpose of the Study:

• To develop and validate a novel computational model for acoustic cavitation flows.
• To accurately depict large geometries and time scales in cavitation simulations.
• To investigate the influence of bubble population characteristics on flow dynamics.

Main Methods:

• Implementation of an Euler-Lagrange approach.
• Integration of a novel Helmholtz solver with a non-linear acoustic attenuation model.
• Simulation of polydisperse bubble populations with local variations.

Main Results:

• The model successfully depicts large geometries and time scales.
• Initial void fraction and bubble population type significantly influence flow velocity.
• Largest bubbles determine peak pressure amplitude, correlating with the Blake threshold.
• Numerical results validate experimental observations of bubble movement influenced by Bjerknes forces.

Conclusions:

• The proposed model provides a robust tool for simulating complex acoustic cavitation scenarios.
• Bubble size is a critical factor in determining pressure amplitude and Bjerknes force reversal.
• The model accurately reproduces experimentally observed phenomena, including size-dependent bubble motion.