利用舰船内部磁场的反演建模方法

Inversion modeling method utilizing ship′s internal magnetic field

积分方程法被广泛应用于舰船磁场反演建模当中,但模型要求有足够多的测量点用于获取舰船在特定深度的磁场。针对积分方程法利用近场磁场建模时精度较差的问题,提出一种增加约束方程的改进措施,并分别开展了薄钢板模型和三维舰船模型磁场数值仿真。采用有限元方法对舰船内部测量点进行初始化选择,基于舰船内部磁场测量值构建了反演模型,采用奇异值分解法求解磁源参数并预测船外空间磁场,舰船外部空间磁场预测结果的均方根误差小于12%。舰船舱段模型磁场推算实验表明,由舱段内部磁场预测外部磁场的均方根误差约为13%,证明了所提出方法的有效性,可以改善传统反演模型的不稳定和精度不足的问题,研究结果可为舰船闭环消磁的算法设计提供思路。

The integral equation method is widely used in ship′s magnetic field inversion modeling,but the model requires enough measurement points to obtain the ship′s magnetic field at a specific depth.To address the problem that the integral equation method uses the near-field magnetic field to model with poor accuracy,an improved measure by adding constraint equation was proposed.The numerical simulation of the magnetic field of a thin steel plate model and a 3D ship model was carried out respectively.The finite element method was used to initialize the selection of the ship′s internal measurement points.The inversion modeling was constructed based on the measured values of the internal magnetic field of the ship and the singular value decomposition method was used to solve the magnetic source parameters and predict the external space magnetic field.It shows that the root mean square error of the prediction results of the external space magnetic field of the ship is less than 12%.The magnetic field measurement experimental verification of the ship cabin model shows that the root mean square error of the prediction of the external magnetic field from the internal magnetic field of the cabin is about 13%,which proves the effectiveness of the proposed method and can improve the instability and insufficient accuracy of the traditional inversion model.The research results can provide ideas for the algorithm design of closed-loop degaussing of ships.