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Title: A passively tunable acoustic metamaterial lens for selective ultrasonic excitation

Abstract

In this paper, we present an approach to ultrasonic beam-forming and beam-steering in structures based on the concept of embedded acoustic metamaterial lenses. The lens design exploits the principle of acoustic drop-channel that enables the dynamic coupling of multiple ultrasonic waveguides at selected frequencies. In contrast with currently available technology, the embedded lens allows exploiting the host structure as a key component of the transducer system therefore enabling directional excitation by means of a single ultrasonic transducer. The design and the performance of the lens are numerically investigated by using Plane Wave Expansion and Finite Difference Time Domain techniques applied to bulk structures. Then, the design is experimentally validated on a thin aluminum plate waveguide where the lens is implemented by through-holes. The dynamic response of the embedded lens is estimated by reconstructing, via Laser Vibrometry, the velocity field induced by a single source located at the center of the lens.

Authors:
;  [1]
  1. Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States)
Publication Date:
OSTI Identifier:
22314409
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 9; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALUMINIUM; BEAMS; DESIGN; EXCITATION; HOLES; LENSES; TRANSDUCERS; WAVE PROPAGATION; WAVEGUIDES

Citation Formats

Zhu, H., and Semperlotti, F., E-mail: Fabio.Semperlotti.1@nd.edu. A passively tunable acoustic metamaterial lens for selective ultrasonic excitation. United States: N. p., 2014. Web. doi:10.1063/1.4894279.
Zhu, H., & Semperlotti, F., E-mail: Fabio.Semperlotti.1@nd.edu. A passively tunable acoustic metamaterial lens for selective ultrasonic excitation. United States. doi:10.1063/1.4894279.
Zhu, H., and Semperlotti, F., E-mail: Fabio.Semperlotti.1@nd.edu. Sun . "A passively tunable acoustic metamaterial lens for selective ultrasonic excitation". United States. doi:10.1063/1.4894279.
@article{osti_22314409,
title = {A passively tunable acoustic metamaterial lens for selective ultrasonic excitation},
author = {Zhu, H. and Semperlotti, F., E-mail: Fabio.Semperlotti.1@nd.edu},
abstractNote = {In this paper, we present an approach to ultrasonic beam-forming and beam-steering in structures based on the concept of embedded acoustic metamaterial lenses. The lens design exploits the principle of acoustic drop-channel that enables the dynamic coupling of multiple ultrasonic waveguides at selected frequencies. In contrast with currently available technology, the embedded lens allows exploiting the host structure as a key component of the transducer system therefore enabling directional excitation by means of a single ultrasonic transducer. The design and the performance of the lens are numerically investigated by using Plane Wave Expansion and Finite Difference Time Domain techniques applied to bulk structures. Then, the design is experimentally validated on a thin aluminum plate waveguide where the lens is implemented by through-holes. The dynamic response of the embedded lens is estimated by reconstructing, via Laser Vibrometry, the velocity field induced by a single source located at the center of the lens.},
doi = {10.1063/1.4894279},
journal = {Journal of Applied Physics},
number = 9,
volume = 116,
place = {United States},
year = {Sun Sep 07 00:00:00 EDT 2014},
month = {Sun Sep 07 00:00:00 EDT 2014}
}
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