Acoustic scattering from a rough sea bottom is recognized as a main source of reverberation. In this study, scattering properties from a layered bottom were exploited based on the finite element model. The scattering ...Acoustic scattering from a rough sea bottom is recognized as a main source of reverberation. In this study, scattering properties from a layered bottom were exploited based on the finite element model. The scattering strength and loss from the layered rough seabed were investigated by ensembling the realizations of rough interface. They were found to be dependent on the thickness of sediment, and interference was significant in the case of thin sediment. Through verification of the finite element model, the scattering loss could be evaluated using the Eckart model with a proper sound speed in the thick sediment. The multiple scattering effect on the sound field was also exploited. It revealed that the effect depended strongly on the bottom type.展开更多
海底微地形粗糙度作为海底沉积物重要的物理性质,对于海洋工程以及海洋科学考察都有着重要意义,如何利用光学理论进行海底微地形粗糙度测量,是近年来该领域研究关注的热点。基于光学中的从明暗恢复形状(shame from shading,SFS)算法,提...海底微地形粗糙度作为海底沉积物重要的物理性质,对于海洋工程以及海洋科学考察都有着重要意义,如何利用光学理论进行海底微地形粗糙度测量,是近年来该领域研究关注的热点。基于光学中的从明暗恢复形状(shame from shading,SFS)算法,提出一种快速的海底微地形粗糙度测量算法,在模型构建同时,添加水下光传播时的吸收和衰减模型,测量出海底的微地形,并用幂律形式进行参数拟合,以表征粗糙度。仿真证明该算法具有95%的置信度,是一种适用于海底微地形粗糙度测量的光学算法,并经过实验验证,证明其有效性和正确性。展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.61571366)the Natural Science Basic Research in Shaanxi Province of China(Grant No.2015JQ5199)the Fund of Science and Technology from the Underwater Test and Control Laboratory(Grant No.9140c260201130c26096)
文摘Acoustic scattering from a rough sea bottom is recognized as a main source of reverberation. In this study, scattering properties from a layered bottom were exploited based on the finite element model. The scattering strength and loss from the layered rough seabed were investigated by ensembling the realizations of rough interface. They were found to be dependent on the thickness of sediment, and interference was significant in the case of thin sediment. Through verification of the finite element model, the scattering loss could be evaluated using the Eckart model with a proper sound speed in the thick sediment. The multiple scattering effect on the sound field was also exploited. It revealed that the effect depended strongly on the bottom type.
文摘海底微地形粗糙度作为海底沉积物重要的物理性质,对于海洋工程以及海洋科学考察都有着重要意义,如何利用光学理论进行海底微地形粗糙度测量,是近年来该领域研究关注的热点。基于光学中的从明暗恢复形状(shame from shading,SFS)算法,提出一种快速的海底微地形粗糙度测量算法,在模型构建同时,添加水下光传播时的吸收和衰减模型,测量出海底的微地形,并用幂律形式进行参数拟合,以表征粗糙度。仿真证明该算法具有95%的置信度,是一种适用于海底微地形粗糙度测量的光学算法,并经过实验验证,证明其有效性和正确性。
