Broadband low-frequency sound isolation by lightweight adaptive metamaterials
Abstract
Blocking broadband low-frequency airborne noises is highly desirable in lots of engineering applications, while it is extremely difficult to be realized with lightweight materials and/or structures. Recently, a new class of lightweight adaptive metamaterials with hybrid shunting circuits has been proposed, demonstrating super broadband structure-borne bandgaps. In this study, we aim at examining their potentials in broadband sound isolation by establishing an analytical model that rigorously combines the piezoelectric dynamic couplings between adaptive metamaterials and acoustics. Sound transmission loss of the adaptive metamaterial is investigated with respect to both the frequency and angular spectrum to demonstrate their sound-insulation effects. We find that efficient sound isolation can indeed be pursued in the broadband bi-spectrum for not only the case of the small resonator's periodicity where only one mode relevant to the mass-spring resonance exists, but also for the large-periodicity scenario, so that the total weight can be even lighter, in which the multiple plate-resonator coupling modes appear. In the latter case, the negative spring stiffness provided by the piezoelectric stack has been utilized to suppress the resonance-induced high acoustic transmission. Such kinds of adaptive metamaterials could open a new approach for broadband noise isolation with extremely lightweight structures.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 20, 2017
- Source ID
- 10.1063/1.5011251
Entities
People
- Guoliang Huang
- Xiaoming Zhou
- Yangyang Chen
- Yunhong Liao
Organizations
- Air Force Office of Scientific Research
- Beijing Institute of Technology
- National Natural Science Foundation of China
- University of Missouri