Wang Xu, Mao Dongxing, Li Yong
Institute of Acoustics, School of Physics Science and Engineering, Tongji University, Shanghai, 200092, People's Republic of China.
Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai, 200092, People's Republic of China.
Sci Rep. 2017 Sep 14;7(1):11604. doi: 10.1038/s41598-017-11846-1.
A skin cloak based on the acoustic metasurface made of graded spiral units is proposed and numerically investigated. The presented skin cloak is an acoustical layer consisting of 80 subwavelength-sized unit cells, which provide precise local phase modulation and hence resort the disturbed sound filed in such a way to hide the object to acoustic wave. Numerical simulations show that the suggested skin cloak both work well under normal and small-angled incidences. By taking the advantage of the spiral-typed metasurface, the suggested skin cloak is rather thin with thickness in the order around 1/7 of the wavelength of target frequency, moreover, the intrinsic characteristics of modest dispersion ensure the skin cloak provides remarkable acoustic invisibility in a broad frequency ranging from 2500 Hz to 3600 Hz.
提出了一种基于由渐变螺旋单元构成的声学超表面的皮肤斗篷，并对其进行了数值研究。所提出的皮肤斗篷是一个由80个亚波长尺寸的单元组成的声学层，这些单元提供精确的局部相位调制，从而以一种方式重塑被干扰的声场，使物体对声波隐形。数值模拟表明，所建议的皮肤斗篷在正常入射和小角度入射下均表现良好。利用螺旋型超表面，所建议的皮肤斗篷相当薄，厚度约为目标频率波长的1/7，此外，适度色散的固有特性确保皮肤斗篷在2500 Hz至3600 Hz的宽频范围内提供显著的声学隐形效果。
