Phononic crystals (PnCs) and acoustic metamaterials (AMMs) are architected structures that show unusual dynamic characteristics due to the presence of band gaps (BGs), which prevent the propagation of mechanical waves in their corresponding frequency range. The two mechanisms of BG formation are Bragg scattering (due to destructive interference at material interfaces) and Mie scattering (resonance frequency of resonators). PnCs and AMMs are used in various applications such as vibration isolation, energy harvesting, acoustic cloaking, and frequency steering among others. In this project, we focus on the wave rejection/steering aspects of PnCs and AMMs. Our objective is to use PnCs and AMMs for removing/redirecting unwanted waves and to improve the accuracy of flow measuring systems.
Phononic structure's design, manufacturing, and testing cycle
The image shows the entire design process, from topology optimization at the periodic unit cell, to the conceptualization of the finite metamaterial-based phononic structure, its realization with 3D printing and characterization of the dynamic behavior before it is implemented in a piezoelectric transducer.
Related publications
S. Valiya Valappil, F. van Keulen, and A. M. Aragón. "An Analytical Procedure for the Accurate Dynamic Analysis of 1D Damped Acoustic/Elastic Metamaterials." Journal of the Mechanics and Physics of Solids (2021), Submitted for Publication.
S. J. van den Boom, R. Abedi, F. van Keulen, and A. M. Aragón. "On the importance of boundary smoothness in the computational design of phononic crystals." (2021), In Preparation.
S. Valiya Valappil, F. van Keulen, H. Goosen, and A. M. Aragón. "Multi-objective design optimization of a 3D phononic crystal waveguide under a hydrostatic loading." (2021), In Preparation.