Dogan Hakan, White Paul R, Leighton Timothy G
Institute of Sound and Vibration Research, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom.
J Acoust Soc Am. 2017 Mar;141(3):2277. doi: 10.1121/1.4978926.
The preceding paper in this series [Mantouka, Dogan, White, and Leighton, J. Acoust. Soc. Am. 140, 274-282 (2016)] presented a nonlinear model for acoustic propagation in gassy marine sediments, the baseline for which was established by Leighton [Geo. Res. Lett. 34, L17607 (2007)]. The current paper aims further advancement on those two studies by demonstrating the particular effects of the sediment rheology, the dispersion and dissipation of the first compressional wave, and the higher order re-scattering from other bubbles. Sediment rheology is included through the sediment porosity and the definition of the contact interfaces of bubbles with the solid grains and the pore water. The intrinsic attenuation and the dispersion of the compressional wave are incorporated using the effective fluid density model [Williams, J. Acoust. Soc. Am. 110, 2276-2281 (2001)] for the far field (fully water-saturated sediment). The multiple scattering from other bubbles is included using the method of Kargl [J. Acoust. Soc. Am. 11, 168-173 (2002)]. The overall nonlinear formulation is then reduced to the linear limit in order to compare with the linear theory of Anderson and Hampton [J. Acoust. Soc. Am. 67, 1890-1903 (1980)], and the results for the damping coefficients, the sound speed, and the attenuation are presented.
本系列的上一篇论文[曼图卡、多安、怀特和莱顿，《美国声学学会杂志》140, 274 - 282 (2016)]提出了一种用于含气海洋沉积物中声传播的非线性模型，其基线由莱顿[《地球物理研究快报》34, L17607 (2007)]建立。本文旨在通过展示沉积物流变学的特殊影响、第一压缩波的色散和耗散以及来自其他气泡的高阶再散射，在这两项研究的基础上进一步推进。通过沉积物孔隙率以及气泡与固体颗粒和孔隙水的接触界面定义来纳入沉积物流变学。对于远场（完全水饱和沉积物），使用有效流体密度模型[威廉姆斯，《美国声学学会杂志》110, 2276 - 2281 (2001)]来纳入压缩波的固有衰减和色散。使用卡尔格的方法[《美国声学学会杂志》11, 168 - 173 (2002)]来纳入来自其他气泡的多次散射。然后将整体非线性公式简化为线性极限，以便与安德森和汉普顿的线性理论[《美国声学学会杂志》67, 1890 - 1903 (1980)]进行比较，并给出阻尼系数、声速和衰减的结果。
