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- Houyou Long
- Key Laboratory of Modern Acoustics, Department of Physics and Collaborative Innovation Center of Advanced Microstructures, Nanjing University 1 , Nanjing 210093, China
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- Ying Cheng
- Key Laboratory of Modern Acoustics, Department of Physics and Collaborative Innovation Center of Advanced Microstructures, Nanjing University 1 , Nanjing 210093, China
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- Xiaojun Liu
- Key Laboratory of Modern Acoustics, Department of Physics and Collaborative Innovation Center of Advanced Microstructures, Nanjing University 1 , Nanjing 210093, China
抄録
<jats:p>We present the mechanism for the asymmetric absorption of acoustic waves in a two-port transparent waveguide system by shunting detuned Helmholtz resonators (HRs) pairs in cascade. Theoretical analysis, numerical simulations, and experimental measurements verify that sound energy is almost totally absorbed (96.1%) at ∼373 Hz when sound waves are incident from one side while it is largely reflected back from the opposite side by judiciously designed HRs to provide manipulated surface impedance matching/mismatching to that of air at the opposite sides of the waveguide. Thus, asymmetric acoustic absorber is achieved at a low frequency. We have further demonstrated the flexibility of this methodology to get non-reciprocal absorption and reflectance in multiband and broadband. Our design advances the concept of asymmetric acoustic manipulation in passive two-port systems and may enable sound-absorbing devices for more versatile applications.</jats:p>
収録刊行物
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- Applied Physics Letters
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Applied Physics Letters 111 (14), 2017-10-02
AIP Publishing