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Updated: Jun 26, 2025
09:39
Characterizing Dissipative Elastic Metamaterials Produced by Additive Manufacturing
Published on: June 28, 2024
904
Broadband vibration mitigation using a two-dimensional acoustic black hole phononic crystala)
1Laboratoire d'Acoustique de l'Université du Mans, UMR CNRS 6613, Avenue Olivier Messiaen, Le Mans, 72085, France.
The Journal of the Acoustical Society of America
|May 8, 2024
Summary
This study merges acoustic black holes (ABHs) with Bragg bandgaps (BGs) in periodically structured metamaterials. The combined effect offers broadband vibration mitigation in stiff, lightweight panels without increasing mass.
Area of Science:
- Metamaterials
- Acoustics
- Vibration Engineering
Background:
- Acoustic black holes (ABHs) are effective structural dampers.
- Periodic lattices create frequency bandgaps (BGs) that forbid wave propagation.
Purpose of the Study:
- To demonstrate the synergistic merging of ABH effects with Bragg BGs.
- To develop stiff, lightweight, nonresonant panels with broadband vibration mitigation.
Main Methods:
- Analysis of band structure using a plane wave expansion model under Kirchhoff's assumptions.
- Design of a finite-size panel based on a hexagonal lattice.
- Experimental characterization of panels with and without viscoelastic coating.
Main Results:
- Demonstration of low-frequency BGs controllable by three geometric parameters.
- Achieved broadband vibration mitigation through the combined ABH and Bragg BG effects.
- Dissipation from ABH does not impede BG filtering.
Conclusions:
- The proposed metamaterial design effectively integrates ABH damping with Bragg BGs.
- This approach yields enhanced vibration mitigation in lightweight structures.
- The method offers tunable, wide-frequency vibration control without added mass.
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