Fawcett John A
Underwater Warfare Section, DRDC Atlantic Research Centre, P.O. Box 1012, Dartmouth, NovaScotia, B2Y 3Z7, Canada.
J Acoust Soc Am. 2021 Oct;150(4):2600. doi: 10.1121/10.0006535.
In this paper, the scattering from a fluid-filled (infinite length) cylinder is considered. This cylinder, C, has a different interior sound speed and density than the surrounding water. Within the cylinder's interior, there are a number of smaller cylinders, inclusions, with yet other sound speeds and densities. The mean coherent field scattered from C is computed using Monte Carlo simulations with respect to the random realizations of the inclusion positions and compared to the results computed using an effective sound speed for C. An original formula for the effective sound speed is derived by equating the reflection coefficient for C (without inclusions) to the expected coherent scattered field from C with inclusions, assuming a single-scattering approximation. A single realization of inclusions is also considered with the backscattered spectra averaged azimuthally over the angle of the source/receiver pair. This result is then compared to the coherent fields predicted by the effective medium theory. This is performed for both spectra and the computed time series.
本文考虑了充满流体的（无限长）圆柱体的散射问题。该圆柱体C，其内部声速和密度与周围水不同。在圆柱体内，有许多较小的圆柱体，即内含物，它们具有其他不同的声速和密度。通过对内含物位置的随机实现进行蒙特卡罗模拟，计算从C散射的平均相干场，并将其与使用C的有效声速计算的结果进行比较。通过在单散射近似下，将C（无内含物）的反射系数与有内含物时C的预期相干散射场相等，推导出有效声速的原始公式。还考虑了内含物的单个实现情况，其反向散射光谱在源/接收器对的角度上进行方位角平均。然后将该结果与有效介质理论预测的相干场进行比较。这是针对光谱和计算的时间序列进行的。
