Gradient-index (GRIN) phononic crystals (PnCs) offer an excellent platform for various applications, including energy harvesting via wave focusing. Despite its versatile wave manipulation capability, the conventional design of GRIN PnCs has thus far been limited to relatively simple shapes, such as cir...
Huang, Acoustic beamwidth compressor using gradient-index phononic crystals, Journal of Physics D: Applied Physics, 42 (2009) 185502.S.-C. S. Lin, B. R. Tittmann, J.-H. Sun, T.-T. Wu, and T. J. Huang, “Acoustic beamwidth compressor using gradient-index phononic crystals,” J ...
The method is based on the homogenization of phononic crystal plates, studied here as finite slices of phononic crystals. A complex unit cell is employed to simultaneously control the refractive index of the three modes, together with thickness variations of the plate, the system has therefore ...
Alternatively, metamaterials or phononic crystals (PCs) offer wave-focusing capabilities with high intensity, which can be tailored by only structural design [15]. In the last decade, gradient index phononic crystal (GRIN-PC) lenses have been proven to focus elastic wave energy at desired ...
Phononic crystals and acoustic metamaterials are periodic structures whose effective properties can be tailored at will to achieve extreme control on wave propagation. Their refractive index is obtained from the homogenization of the infinite periodic system, but it is possible to locally change the ...
CrystalsRefractive indexWave platesLens designUltrasonicsWaveguidesPhase velocityOne of the current challenges in the guided wave ultrasonic testing of large-scale structures is attenuation. In this study, elastic wave propagation characteristics of a composite plate that is sampled from aerospace industry ...
It is shown that by means of complex graded phononic crystals and thickness variations it is possible to independently design the three refractive indexes of these waves, allowing therefore their simultaneous control. The effective medium theory required for this purpose is presented, and the method ...
can be achieved using various methods. One common approach involves using elastic metamaterials and phononic crystals, as demonstrated in numerous publications (e.g., [1], [2], [3], [4], [5], [6], [7], [8]). Functionally graded materials (FGMs) are a particularly interesting means ...