Shao Yu, Wang Shumin
Wireless Innovation Lab, School of Information Science and Engineering, Yunnan University, Kunming, Yunnan 650091, China.
University of North Carolina/North Carolina State University Joint Department of Biomedical Engineering, University of North Carolina, Chapel Hill, 152 MacNider Hall, CB 7575, Chapel Hill, North Carolina 27599, USA.
J Acoust Soc Am. 2016 Dec;140(6):4183. doi: 10.1121/1.4971161.
The numerical simulation of acoustic scattering from elastic objects near a water-sand interface is critical to underwater target identification. Frequency-domain methods are computationally expensive, especially for large-scale broadband problems. A numerical technique is proposed to enable the efficient use of finite-difference time-domain method for broadband simulations. By incorporating a total-field/scattered-field boundary, the simulation domain is restricted inside a tightly bounded region. The incident field is further synthesized by the Fourier transform for both subcritical and supercritical incidences. Finally, the scattered far field is computed using a half-space Green's function. Numerical examples are further provided to demonstrate the accuracy and efficiency of the proposed technique.
水-沙界面附近弹性物体声散射的数值模拟对于水下目标识别至关重要。频域方法计算成本高昂，尤其是对于大规模宽带问题。本文提出一种数值技术，以便能有效地将时域有限差分方法用于宽带模拟。通过引入总场/散射场边界，模拟域被限制在一个紧密界定的区域内。对于亚临界和超临界入射，通过傅里叶变换进一步合成入射场。最后，使用半空间格林函数计算散射远场。还提供了数值算例以证明所提技术的准确性和效率。
