Role of a fractal shape of the inclusions on acoustic attenuation in a nanocomposite
H. Luo,
Y. Ren,
A. Gravouil,
V. M. Giordano,
Q. Zhou,
H. Wang,
A. Tanguy
Affiliations
H. Luo
University Lyon, INSA-Lyon, CNRS UMR5259, LaMCoS, Lyon F-69621, France
Y. Ren
State Key Laboratory of Solidification Processing, Center of Advanced Lubrication and Seal Materials, Northwestern Polytechnical University, Xi’an, Shaanxi 710072, People’s Republic of China
A. Gravouil
University Lyon, INSA-Lyon, CNRS UMR5259, LaMCoS, Lyon F-69621, France
V. M. Giordano
Institut Lumière Matière, UMR 5306 Université Lyon 1-CNRS, F-69622 Villeurbanne Cedex, France
Q. Zhou
State Key Laboratory of Solidification Processing, Center of Advanced Lubrication and Seal Materials, Northwestern Polytechnical University, Xi’an, Shaanxi 710072, People’s Republic of China
H. Wang
State Key Laboratory of Solidification Processing, Center of Advanced Lubrication and Seal Materials, Northwestern Polytechnical University, Xi’an, Shaanxi 710072, People’s Republic of China
A. Tanguy
University Lyon, INSA-Lyon, CNRS UMR5259, LaMCoS, Lyon F-69621, France
Phononic materials structured at the macro- or nano-scale are at the forefront of materials research for controlling transport of sound and heat, respectively. Besides the structure length scale, the exact geometry has been found to be of relevance as well. In this work, we provide an extensive finite element investigation of the effect of the shape of periodically dispersed inclusions in a 2D matrix on propagation and attenuation of an acoustic wave packet. We show that, by significantly complexifying the shape from circular to fractal-like (dendrite shape), phonon scattering at wavelengths comparable with the inner structure of the inclusion is enhanced, leading to a strong attenuation that can be fitted by a compressed exponential function, while in the circular case, the diffusive regime is observed.
