有限宽洋流产生的感应磁场数值分析  

Numerical analysis of induced magnetic field generated by finite-width ocean current

作　　者：王瑞坤 李腾飞 刘健 魏宝君 石杰栋 WANG RuiKun;LI TengFei;LIU Jian;WEI BaoJun;SHI JieDong(College of Science in China University of Petroleum(East China),Qingdao 266580,China;China Ship Science Research Center,Wuxi 214026,China)

机构地区：[1]中国石油大学(华东)理学院,青岛266580 [2]中国船舶科学研究中心,无锡214026

出　　处：《地球物理学进展》2024年第2期770-780,共11页Progress in Geophysics

基　　金：国家重点研发计划项目(2019YFC1408104);中央高校基本科研业务费专项资金(22CX03017A)联合资助。

摘　　要：为了定量计算有限宽洋流产生的感应磁场,建立分层洋流物理模型,提出了有限宽洋流产生的感应磁场的计算方法.依托于分层洋流物理模型,计算矢势,得出有限宽洋流产生感应磁场的数值解.当洋流宽度趋于无穷大时,数值结果与无限宽洋流模型的解析结果一致,验证了方法的正确性.基于得到的数值表达式,分析海水宽度以及速度对感应磁场的影响规律.结果表明:对于常速洋流,宽度越大感应磁场在洋流中央的分布越稳定,在边缘处会减小,其次感应磁场在深度方向呈现线性分布的特点;对于水平速度衰减的洋流,洋流宽度以及速度的衰减程度对感应磁场的分布都有明显的影响,在合理的参数范围内,速度的衰减程度对感应磁场的影响更大;对于垂直速度衰减的洋流,感应磁场在深度方向存在一极大值,不同的洋流宽度以及速度衰减程度会对极值点的位置有明显的影响.In order to quantitatively calculate the induced magnetic field generated by finite-width ocean currents,a stratified ocean current mathematical model was established,and a calculation method for the induced magnetic field generated by finite-width ocean currents was proposed.Based on the stratified ocean current mathematical model,the vector potential was calculated to obtain the numerical solution of the induced magnetic field generated by finite-width ocean currents.When the width of the ocean current tends to infinity,the numerical results are consistent with the analytical results of the infinite-width ocean current model,verifying the correctness of the method.Based on the obtained numerical expressions,the influence of seawater width and velocity on the induced magnetic field was analyzed.The results show that for constant-speed ocean currents,the wider the width,the more stable the distribution of the induced magnetic field in the center of the ocean current,and it decreases at the edges.Secondly,the induced magnetic field exhibits a linear distribution in the depth direction.For ocean currents with horizontal velocity decay,both the width of the ocean current and the degree of velocity decay have a significant impact on the distribution of the induced magnetic field.Within a reasonable range of parameters,the degree of velocity decay has a greater influence on the induced magnetic field.For ocean currents with vertical velocity decay,the induced magnetic field has a maximum value in the depth direction,and different ocean current widths and degrees of velocity decay have a significant impact on the position of the maximum value.

关 键 词：有限宽洋流 感应磁场 多层洋流模型 洋流速度 海洋电磁探测 

分 类 号：P631[天文地球—地质矿产勘探]