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Title: Energy trapping in a phononic crystal cavity enhanced by nonreciprocal acoustic wave transmission
Defect mode induced energy trapping at the bandgap frequency of a phononic crystal has been widely explored. Unlike this extensively used mechanism, this work reports the use of nonreciprocity in the transmission band to trap energy inside a phononic crystal cavity. Passive nonreciprocity is due to natural viscosity of the background liquid (water) and asymmetry of aluminum scatterers. The level of nonresonant energy trapping was compared for three cavities with different symmetry. Enhancement of energy trapping at a frequency of 624 kHz was observed experimentally for the cavity where nonreciprocity suppresses acoustic radiation into environment. Experimental results were further investigated and confirmed using finite element numerical analysis.  more » « less
Award ID(s):
1741677
NSF-PAR ID:
10470172
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Applied Acoustics
Volume:
203
Issue:
C
ISSN:
0003-682X
Page Range / eLocation ID:
109192-1-8
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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