舰船尾流的多波束声纳探测与特性分析研究

The research on the properties of ship wakes not only have urgent needs in the military field such as ship blanking and wake homing torpedoes, but also play an increasingly important role in civilian fields such as ship shape and draft design and optimization, propeller performance evaluation, harbor and river shore erosion and construction safety. The essential basic work of study the characteristic of the ship wake is how to obtain the precise information of wake; while detecting the acoustic properties of the ship wake has been a difficult problem and also a hot spot in home and abroad at present. The conventional ship wake detection method using single-beam echo sonar relies on single point and single-frequency detection. The method has low efficiency and is not able to get fully acoustic scattering feature and space distribution scale features. To solve this problem, the project proposed using the self-developed broadband multi-beam sonar as core detection equipment, combined the real ship experiment on the lake and on the sea, studied on ship wakes acoustic scattering and spatial distribution features based on acoustic signal processing and sonar imaging processing. The main study includes: (1) The acoustic backscattering feature and multi-beam sonar echo model of the ship wakes; (2)The characteristics analysis of acoustic scattering intensity from ship wake;(3) Ship wake detection based on the estimation of distributed source; (4) Ship wake imaging and the spatial distribution geometric feature extraction method; (5) Experimental study of ship wake multi-beam sonar detection and imaging.

舰船尾流特性研究不仅在舰船消隐、尾流自导鱼雷等军事领域需求迫切，而且对指导船型和吃水优化设计、螺旋桨性能评价、港口河道岸基冲刷与施工安全影响等民用领域的作用也日益突出。研究舰船尾流特性的必备基础性工作是如何获得尾流的精细信息，而尾流信息的声学探测则是当前国内外研究的热点和难点问题之一。以往依靠单波束声纳进行单点、单频探测舰船尾流的方法不仅效率低，且无法全面获得尾流声散射特性和空间分布尺度特性，为此本项目提出采用宽带多波束探测声纳为核心探测设备，结合湖上和海上实船试验，从水声信号处理和声纳图像处理两方面出发，开展舰船尾流信息获取方法和特性分析研究，主要研究内容包括：（1）尾流声散射特性及其多波束回波模型；（2）舰船尾流声散射强度特征分析研究；（3）基于分布源的尾流方位估计算法研究；（4）舰船尾流声成像与空间分布尺度特征提取方法研究；（5）尾流多波束声纳探测与成像实船试验研究。

海洋面积辽阔，资源丰富，能够为人类的生活生产提供丰富的物质基础，舰船作为人类活动范围向海洋扩展的主要交通工具之一，与舰船相关的研究在各学科中都受到广泛的关注。舰船在航行时，由于螺旋桨空化、壳体侧壁与水摩擦、溶入水中的空气及舰船运动时卷入水中的空气搅拌破碎等原因，会在水面留下舰船的运动轨迹，称为舰船尾流，尾流特性与舰船形状、尺寸、吃水深度以及螺旋桨深度、大小、发动机功率、航速和海况等多种因素有关，要搞清楚这些因素的内在关系首先是要对尾流进行精细探测并获得尾流的特性信息。本项目从气泡谐振特性理论模型出发，分析了气泡振动特性及其声学特征，分析了气泡尾流声散射特征，构建了尾流声回波模型，并基于多波束声呐展开了对尾流回波的强度分析、定位方法的研究，提出了一种基于空间反演的气泡尾流特征提取方法，并通过水池试验、湖上试验数据对上述理论成果进行验证。最终的研究目标是，通过上述研究工作，提出基于多波束声呐气泡尾流探测及目标特征提取方法，为提舰船气泡尾流声探测、声追踪提供理论基础。