Session: 16-01-01: Government Agency Student Poster Competition

Paper Number: 150930

150930 - Flexible Standing Wave Generation Between Variously Oriented Surfaces via Acoustic Metasurface Retroreflectors and Deflectors 

In recent years, acoustic devices based on standing wave configurations have garnered interest in various areas such as health diagnostics, tissue engineering, and industrial production. Such devices feature a straightforward setup, cost-effective pricing, significant compatibility with biological systems, and minimal contamination risk by reagents. Their functionalities range from non-contact microparticle manipulation and expedition of microfluidics mixing process to microscale fiber self-assembly within some additive manufacturing processes through the generation of periodic acoustic pressure fields. Conventional methods for such system generation typically necessitate the use of two or more transducers or a reflector positioned in parallel to the acoustic source to generate the needed standing wave. However, generating a standing wave at a tilted angle poses challenges due to the need for special configuration of the acoustic source and the reflecting surface. This often requires multiple acoustic sources oriented in a specific way, leading to restricted design flexibility and increased setup complexity. In this paper, an innovative approach is presented that allows the production of versatile acoustic standing wave field at various angles by employing a combination of acoustic metasurface deflector and retroreflector. The acoustic deflector allows the manipulation of the direction of the incoming sound wave, steering it towards a specific chosen angle which when combined with a retroreflector, allows the generation of a standing wave that is not constrained by the relative angles of the two involved surfaces. Furthermore, the proposed approach allows the customization of the standing wave patterns between any two surfaces, irrespective of their orientation, and permits the generation of the acoustic standing wave fields at multiple predetermined angles. The performance of the proposed system was assessed through computational modeling with COMSOL 6.1 software, along with underwater experimental validations using hydrophone needle measurements based on a combination of a 3D-printed prototype of the acoustic deflector and a stainless steel micromachined sample of the retroreflector. The numerical simulations confirmed that the performance of the proposed standing wave system aligned well with the outcomes anticipated by the theoretical principles governing the design of metasurfaces tailored for the modulation of sound waves. The findings were further supported by the experimental results which involved generating a standing wave tilted at a 45-degree angle to serve as a demonstrative case using the proposed acoustic deflector-retroreflector system. Moreover, results suggest that with careful crafting of the metasurface deflectors and retroreflectors, versatile standing wave patterns between arbitrarily oriented surfaces can be generated. The proposed approach can enhance the effectiveness of standing wave techniques for various applications, consequently expanding the spectrum of feasible uses for ultrasonic and acoustofluidic devices.

Presenting Author: Chadi Ellouzi Rowan University

Presenting Author Biography: Chadi Ellouzi is currently a Ph.D. student in Mechanical Engineering at Rowan University, New Jersey. His research in the Functional Materials and Structures Laboratory at Rowan University focuses on two areas: (1) Acoustofluidics and its application in cell manipulation using bulk and surface acoustic waves; (2) Acoustic Metamaterials and Metasurfaces and their applications in the manipulation and control of acoustic waves. Chadi earned his B.S. in Aerospace Engineering from the University of Aviation and Technology, Tunisia in 2016, and his M.S. in Mechanical Engineering from Rowan University, New Jersey in 2021.

Authors:

Chadi Ellouzi Rowan University
Ali Zabihi Rowan University
Farhood Aghdasi Rowan University
Chen Shen Rowan University