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Characterizing Dissipative Elastic Metamaterials Produced by Additive Manufacturing
Published on: June 28, 2024
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An acoustic metamaterial with space-time modulated densitya).
1Huzhou Key Laboratory of Green Energy Materials and Battery Cascade Utilization, School of Intelligent Manufacturing, Huzhou College, Huzhou, Zhejiang 313000, China.
The Journal of the Acoustical Society of America
|December 13, 2024
Summary
This study introduces a novel acoustic metamaterial using space-time modulation to control wave behavior. The proposed system demonstrates nonreciprocal functionalities like unidirectional amplification and frequency conversion.
Area of Science:
- Acoustics
- Metamaterials
- Wave physics
Background:
- Space-time modulation offers advanced control over wave phenomena.
- Nonreciprocal wave manipulation is a key area in wave physics.
Purpose of the Study:
- To propose and analyze a one-dimensional space-time modulated membrane system.
- To realize an acoustic metamaterial with space-time modulated effective density.
- To investigate nonreciprocal acoustic functionalities.
Main Methods:
- Effective medium method
- Transfer matrix method
- Time-domain simulation
Main Results:
- The system supports unidirectional parametric amplification.
- The system supports parametric frequency conversion.
- Nonreciprocal acoustic functionalities are achieved through specific modulation profiles.
Conclusions:
- The proposed space-time modulated membrane system is a viable acoustic metamaterial.
- The system enables advanced nonreciprocal wave control.
- Different modulation profiles lead to distinct functionalities.
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