Modelling of acoustic scattering from a submarine
Modelling of acoustic scattering from a submarine
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潜艇声散射建模
DOI：
10.1121/1.4767963
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发表时间：
2012
影响因子：
5.7
通讯作者：
I. Karasalo
中科院分区：
文献类型：
--
作者：
I. Karasalo
给出了由船体和帆组成的简化模型潜艇水声散射的数值计算结果。模型潜艇的各个部件通过单位球面的光滑映射进行参数化，单位球面的光滑映射是通过将高阶B-样条展开式与零件表面形状上的CAD数据进行拟合而获得的。潜艇被放置在一个大约50米深的水柱中，覆盖在分层的流体海床上。考虑了频率在0.5~kHz-30~kHz范围内的垂直定向源的瞬时脉冲，源的方位角在100~m范围内变化。散射回波由以震源为中心的垂直接收器阵列记录。分别用基于声线理论和基尔霍夫散射近似的快速近似方法计算目标回波。通过与高阶边界积分方程(BIE)方法计算的全场精确解的比较，评估了这些近似方法在低频情况下的精度。该方法基于以配点为中心的类极坐标的离散化、点配置和数值积分。模型潜艇的各个部件通过单位球面的光滑映射进行参数化，单位球面的光滑映射是通过将高阶B-样条展开式与零件表面形状上的CAD数据进行拟合而获得的。潜艇被放置在一个大约50米深的水柱中，覆盖在分层的流体海床上。考虑了频率在0.5~kHz-30~kHz范围内的垂直定向源的瞬时脉冲，源的方位角在100~m范围内变化。散射回波由以震源为中心的垂直接收器阵列记录。分别用基于声线理论和基尔霍夫散射近似的快速近似方法计算目标回波。在低频情况下，通过与精确的全场解进行比较，评估了这些近似方法的精度。
Numerical predictions are presented of hydroacoustic scattering from a simplified model submarine composed of a hull and a sail only. The individual parts of the model submarine are parameterized by smooth maps of the unit sphere, obtained by fitting high-order B-spline expansions to CAD data on the shape of the surfaces of the parts. The submarine is placed in a ca 50 m deep water column overlying a layered fluid seabed. Transient pulses from a vertically directive source with frequencies in the range 0.5~kHz - 30~kHz are considered, with the source located at range 100~m at varying aspect angles. The scattered echoes are recorded by a vertical receiver array with center at the source. The target echoes are computed with fast approximative methods derived from acoustic ray theory and the Kirchhoff scattering approximation, respectively. The accuracy of these approximative techniques is assessed in the low frequency cases by comparisons with an accurate full-field solution computed with a high-order Boundary Integral Equation (BIE) method, based on discretization by B-spline expansion, point collocation and numerical integration in polar-like coordinates centered at the collocation point.Numerical predictions are presented of hydroacoustic scattering from a simplified model submarine composed of a hull and a sail only. The individual parts of the model submarine are parameterized by smooth maps of the unit sphere, obtained by fitting high-order B-spline expansions to CAD data on the shape of the surfaces of the parts. The submarine is placed in a ca 50 m deep water column overlying a layered fluid seabed. Transient pulses from a vertically directive source with frequencies in the range 0.5~kHz - 30~kHz are considered, with the source located at range 100~m at varying aspect angles. The scattered echoes are recorded by a vertical receiver array with center at the source. The target echoes are computed with fast approximative methods derived from acoustic ray theory and the Kirchhoff scattering approximation, respectively. The accuracy of these approximative techniques is assessed in the low frequency cases by comparisons with an accurate full-field solu...