An efficient multiscale method for subwavelength transient analysis of acoustic metamaterials

Area of Science:

• Acoustics
• Materials Science
• Continuum Mechanics

Background:

• Locally resonant acoustic metamaterials offer unique wave manipulation properties.
• Subwavelength acoustic phenomena require advanced modeling techniques.
• Homogenization methods are crucial for bridging micro-scale features to macro-scale behavior.

Purpose of the Study:

• To develop a reduced-order homogenization framework for acoustic metamaterials.
• To enable both time and frequency domain analyses of metamaterial behavior.
• To capture non-standard constitutive properties like negative effective modulus and density.

Main Methods:

• Reduced-order homogenization framework construction.
• Development of a macro-scale-enriched continuum model.
• Unit cell response analysis in steady-state and local resonance regimes.
• Frequency domain numerical simulations.

Main Results:

• A non-standard constitutive model for the homogenized continuum was established.
• Metamaterial behaviors including negative effective bulk modulus, negative effective density, and Willis coupling were captured.
• The framework demonstrated efficiency and suitability in frequency domain analysis.

Conclusions:

• The proposed reduced-order homogenization framework effectively models subwavelength acoustic metamaterials.
• The framework accurately represents unique metamaterial constitutive behaviors.
• This approach is suitable for both time and frequency domain analyses in acoustic metamaterial science.