Underwater broadband acoustic scattering modelling based on FDTD

摘要

A modified finite-difference time-domain (FDTD)method is described in this paper. The absorption coefficientwhich is frequency-dependent is considered, and it is used tocompute broadband acoustic scattering model of underwatercomplex object. The perfectly matched layer (PML) absorbingboundary condition (ABC) is applied to this work. Consideringcomputation and accuracy comprehensively, PML boundarylayer number and the attenuation coefficient is set at propervalues. Computer Graphics are applied to mesh-generating ofthe irregular object. A pulse of LFM signal is used to simulatewide-band acoustic scattering field of a circle in 2D and acomplex object in 3D. And the scattered acoustic pressurewaveforms of some certain points are computed in thecalculation field. Results obtained from simulation confirm thehigh accuracy of the proposed method.