浅海中潜艇腐蚀相关静态磁场特征预测

为对浅海环境中潜艇腐蚀相关静态磁场进行特征预测，采用3层平行分层导电媒质模型模拟浅海环境，采用水平直流电偶极子模拟场源。推导了水平直流电偶极子在全空间中的磁场分布表达式，在此基础上，采用数值仿真的方法分析海水中腐蚀相关静态磁场的分布特征及远场衰减规律，并进一步分析海洋环境，如海床电导率、海水深度、空气-海水界面等因素对场的影响。分析结果表明：浅海中潜艇腐蚀相关静态磁场量值可测，分布特征明显，远场按距离的平方反比衰减，是值得重视的探测或打击信号源；由于导电媒质中空间电流的影响，电导率小于海水的海床媒质使海水中的总磁场略有增强，而空气-海水界面则使其略有减弱。研究结果为进一步的实际应用奠定了基础。

Calculation of the Static Corrosion-related-magnetic Field Produced by a Submarine in Shallow Sea

In order to forecast the distribution characteristics of the static corrosion-related-magnetic field produced by a submarine in shallow sea, a static horizontal electric dipole is adopted to simulate the static magnetic field source, and a three-layered conductive media mode is adopted to simulate the shallow sea environment. At first, the expressions for the magnetic field distribution in all the spaces produced by a static horizontal electric dipole located in the middle layer are derived, and then the numerical simulation method is used to analyze the distribution characteristics and the attenuation law of far field, as well as the influences of the ocean environmental factors, such as conductivity, seawater depth, and air-water interface, on it. The research results show that the static corrosion-related-magnetic field of a submarine in shallow sea has measureable magnitude and obvious distribution characteristic in seawater, and its far field degenerates with the inverse square of distance, so it can become an important signal source for detection or striking. In addition, because of the influence of the space current in conductive medium, the seabed of which conductivity is less than seawater enhances the magnetic field in seawater, and the air-seawater interface weakens the field. The research results lay a foundation for the further actual application.