Sound attenuation in high mach number oscillating bubble media

Area of Science:

• Acoustics
• Fluid Dynamics
• Nonlinear Wave Propagation

Background:

• Sound attenuation in bubbly media is crucial for various applications.
• Previous models often simplify nonlinear effects and high Mach number phenomena.
• Bubble oscillations significantly influence acoustic damping.

Purpose of the Study:

• To develop and validate a nonlinear sound propagation model for bubble-containing media at high Mach numbers.
• To investigate the impact of higher-order liquid compression effects on sound attenuation.
• To extend theories of bubble-related acoustic damping factors to higher Mach numbers.

Main Methods:

• Development of a nonlinear sound propagation model incorporating second-order liquid compression terms.
• Theoretical analysis and numerical simulations of sound attenuation.
• Comparison of the proposed model with linear and low-order nonlinear models.
• Analysis of pressure-dependent attenuation variations with bubble radius and number density.

Main Results:

• Radiation damping becomes the dominant attenuation component at high Mach numbers.
• Higher driving amplitudes and liquid compressibility effects necessitate the proposed model.
• Smaller bubble radii amplify the importance of compressibility and radiation damping.
• The proposed model shows significant differences from low-order models for small bubbles.

Conclusions:

• The developed nonlinear model accurately captures sound attenuation in bubbly media at high Mach numbers.
• High-order liquid compression effects are critical for accurate acoustic damping predictions.
• The model is essential for understanding pressure-dependent attenuation, particularly in systems with small bubbles.