舰船腐蚀相关轴频电磁场场源建模

Modeling of ship corrosion related shaft-rate electromagnetic field

为了开展轴频电磁场场源建模研究,根据舰船水下腐蚀相关轴频电磁场信号的产生机理,借鉴极低频发信台的建造原理,提出了以海水、螺旋桨、转动轴、船壳、辅助阳极等形成的闭合回路为线索,对舰船进行电流环建模,即将轴频电磁场场源等效为由转动轴作弦与趋肤深度相关的曲线组成的闭合曲线。进行了验证试验,试验结果表明:腐蚀相关轴频电磁场场源不仅是辅助阳极和螺旋桨之间的电流线,还包括海水中分布的空间电流;基于电流环模型的轴频电磁场产生机理模型与试验结果具有很好的一致性,该模型为轴频电磁场建模及传播规律研究提供了一个新的思路和方法。

To conduct modeling research for the source of shaft-rate electromagnetic field, on the basis of the generation mechanism of the underwater corrosion-related shaft-rate electromagnetic field of a ship and in view of the building principle of a low-frequency transmitting station, this paper proposed a current loop modeling for a ship. This model uses the closed circuit formed by the following parts as an example： sea water, propel- ler, axis of rotation, hull, and auxiliary anode, i. e. , the shaft-rate electromagnetic field source is equivalent to a closed curve formed by the curves related to the skin depth with the axle of rotation as a chord. A verifica- tion test was conducted in the lab. Experimental results show that the field source of corrosion-related shaft-rate electromagnetic field includes not only the current line between the auxiliary anode and the propeller but also the spatial current distributed in sea water. The generation mechanism model of the shaft-rate electromagnetic field based on the current loop model is consistent with the experimental results. The model offers a new concept and method for modeling the shaft-rate electromagnetic field and conducting research on the propagation law.