根据海上实测海水电导率参数，建立空气—分层海水—海床5层海洋环境模型。基于传统的水平电偶极子空气-海水-海床3层介质模型中水下电场衰减规律和分布特性，通过对海水进一步分层的多层介质模型构建数学模型，进行理论推导和仿真计算，给出场源强度为1A·m，深度为4 m，频率为1 Hz时电场在不同水深处的空间分布及正下方Y=0测线上的水下电场分布。结果表明，随着水深的增加，电场X分量与电场Z分量之比是增加的；在海水-海床界面上，测线上电场Z分量最大值约为电场X分量最大值的1/4，电场Y分量最大值相对Y=0处有一定的偏移。从衰减曲线可以看出，在60～500 m范围内电场X分量和电场Z分量沿径向随距离呈3次方衰减。
Based on the measured sea water conductivity parameters, a five-layer marine environment model of air - stratified sea water - seabed was established. Based on the underwater electric field attenuation regularity and distribution characteristics in air - water - sea three layer medium of the traditional horizontal electric dipole, a further stratified sea multilayer medium model was presented to construct the mathematical model. And theoretical derivation and simulation calculation was executed. The source strength was assumed to be 1 A·m in the depth of 4 m. The spatial distribution of electric field in different water depths and right Y =0 online measurement of underwater electric field distribution was showed when the frequency was 1 Hz. The results showed that the ratio of Ex to Ez increased with the increase of water depth. On the sea-seabed interface, the maximum value of Ez on the survey line was about 1/4 of the Ex, and the maximum value of Ey was offset to a certain extent from the point of Y=0. It was seen from the attenuation curve that Ex and Ez decayed to the third power along the radial direction in the distance within the range of 60～500 m.
2021,43(7): 137-142 收稿日期：2020-08-22
DOI：10.3404/j.issn.1672-7649.2021.07.028
分类号：P76
基金项目：水下测控技术重点实验室基金资助项目(6142407190403)
作者简介：焦达文(1987-),男,工程师,研究方向为水下电磁场建模仿真与分析
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