|
|
A Fast Forward Modeling Method for High Precision Induced Magnetic Field of Ships |
He Baowei, Sun Zhaolong, Liu Yuelin, Zhou Guohua, Tang Liezheng |
School of Electrical Engineering Naval University of Engineering Wuhan 430033 China |
|
|
Abstract Mastering the distribution of a ship’s induced magnetic field is an important issue for implementing magnetic stealth technology, and the integral equation method is one of the main methods to calculate the ship’s induced magnetic field. The integral equation method only needs to discretize the ferromagnetic region and does not need to consider the boundary conditions, so it has been widely concerned and applied. The traditional vector integral equation for modeling induced magnetic fields has the problems of low efficiency and an enormous computational burden. Considering that there are many discrete elements of large ferromagnetic objects such as ships, the coupling coefficient between elements forms a huge asymmetric dense matrix. As a result, the computing time and memory requirement will increase sharply with the increase of the number of elements. Therefore, a scalar magnetic potential integral equation method based on surface elements is proposed. Since the integral equation method needs to obtain the magnetic susceptibility of ferromagnetic materials, the equivalent magnetic susceptibility inversion model is established based on a multi-level adaptive cross approximation (MLACA) algorithm. Firstly, the scalar magnetic potential integral formula based on triangular surface elements is derived. According to the principle of linear interpolation, the scalar magnetic potential of the center point of discrete elements is expressed by interpolation function and node scalar magnetic potential, and the elements’ coupling coefficient matrix is obtained by establishing a local coordinate system. Therefore, the scalar integral method of surface elements is obtained for solving the ship’s induced magnetic field. Secondly, the MLACA algorithm is introduced to guarantee the accuracy of magnetic field calculation and reduce the memory requirement and computing time of the computer. Finally, aiming at the problem that the magnetic parameters of ferromagnetic materials of ships are not easy to obtain, a magnetic susceptibility inversion model is established based on the measured magnetic field values and the forward coupling model. The magnetic field fitting degree, prior distribution of magnetic susceptibility, and smooth constraint are the objective function. The spatial distribution of equivalent magnetic susceptibility is optimized by simulated annealing (SA) algorithms. A numerical simulation of the spherical iron shell shows that the proposed scalar magnetic potential coupling forward modeling method can efficiently obtain the ship’s induced magnetic field with high precision. For the same discrete elements, compared with the vector method, the scalar method can save about 97% of the memory consumption and 65% of the computing time, which verifies the effectiveness of the scalar magnetic potential integral equation method based on the MLACA algorithm. According to the inversion model, the equivalent magnetic susceptibility of the spherical iron shell is optimized by the SA algorithm, which is utilized to predict the spherical shell of other positions, and the average relative error is only 2.2%. After using of smooth constraint condition, the equivalent magnetic susceptibility obtained is smoother. In order to verify the practicability of the proposed forward modeling method and magnetic susceptibility inversion method in engineering, an experimental scheme was designed for a reduced-scale ship model with unknown magnetic parameters. Firstly, the equivalent magnetic susceptibility distribution of the ship model is obtained by measuring the magnetic field of the ship model at the z1 plane, and it is used to predict the induced magnetic field at the z2 plane. The magnetic field fitting and prediction errors of the ship are about 5.0%, indicating that the proposed forward modeling model of induced magnetic field and the inverse optimization model of equivalent magnetic susceptibility can be used for induced magnetic field modeling of large ships with high precision and can provide support for the implementation of magnetic stealth technology on ships.
|
Received: 22 November 2022
|
|
|
|
|
[1] Holmes J J.Reduction of a ship's magnetic field signatures[M]. Maryland, USA: Morgan & Claypool Publishers, 2008. [2] 刘大明. 舰船消磁理论与方法[M]. 北京: 国防工业出版社, 2011. [3] 郭成豹, 殷琦琦. 舰船磁场磁单极子阵列法建模技术[J]. 物理学报, 2019, 68(11): 106-115. Guo Chengbao, Yin Qiqi.Magnetic monopole array model for modeling ship magnetic signatures[J]. Acta Physica Sinica, 2019, 68(11): 106-115. [4] 戴忠华, 周穗华, 张晓兵. 多目标优化的舰船磁场建模方法[J]. 物理学报, 2021, 70(16): 147-159. Dai Zhonghua, Zhou Suihua, Zhang Xiaobing.Multi- objective optimization of ship magnetic field mode- ling method[J]. Acta Physica Sinica, 2021, 70(16): 147-159. [5] 刘琪, 孙兆龙, 姜润翔, 等. 一种舰船下方磁场的信号重构及换算方法[J]. 电工技术学报, 2022, 37(15): 3723-3732. Liu Qi, Sun Zhaolong, Jiang Runxiang, et al.A signal reconstruction and conversion method of magnetic field under ship[J]. Transactions of China Electro- technical Society, 2022, 37(15): 3723-3732. [6] 刘芙妍, 颜冰. 磁偶极子阵列模型的适用性研究与优化分析[J]. 物理学报, 2022, 71(12): 36-48. Liu Fuyan, Yan Bing.Applicability and optimization analysis of magnetic dipole array model[J]. Acta Physica Sinica, 2022, 71(12): 36-48. [7] 徐庆林, 王向军, 张建春, 等. 921A钢板腐蚀电场的Frumkin修正[J]. 电工技术学报, 2020, 35(14): 2951-2958. Xu Qinglin, Wang Xiangjun, Zhang Jianchun, et al.Frumkin correction of corrosion electric field gen- erated by 921A steel[J]. Transactions of China Electrotechnical Society, 2020, 35(14): 2951-2958. [8] 饶凡, 吴旭升, 高嵬, 等. 两极永磁电机静态内外磁场研究[J]. 电工技术学报, 2021, 36(14): 2936-2944. Rao Fan, Wu Xusheng, Gao Wei, et al.Study on internal and external magnetic field of static two-pole permanent magnet motor[J]. Transactions of China Electrotechnical Society, 2021, 36(14): 2936-2944. [9] Chadebec O, Coulomb J L, Janet F.A review of magnetostatic moment method[J]. IEEE Transactions on Magnetics, 2006, 42(4): 515-520. [10] Fan Mingwu, Shao Hanguang, Wang Jingguo.Some experiences of using integral equation method to calculate magnetostatic fields[J]. IEEE Transactions on Magnetics, 1985, 21(6): 2185-2187. [11] 倪振群, 蔡雪祥, 翁行泰. 舰船主甲板模型感应磁场的计算[J]. 上海交通大学学报, 1996, 30(7): 83-88. Ni Zhenqun, Cai Xuexiang, Weng Xingtai.Com- putation of inductive magnetic field induced by vessel’s main deck model[J]. Journal of Shanghai Jiaotong University, 1996, 30(7): 83-88. [12] 周国华, 肖昌汉, 刘胜道, 等. 基于六面体单元表面磁场积分法求解三维静磁场[J]. 电工技术学报, 2009, 24(3): 1-7. Zhou Guohua, Xiao Changhan, Liu Shengdao, et al.3D magnetostatic field computation with hexahedral surface integral equation method[J]. Transactions of China Electrotechnical Society, 2009, 24(3): 1-7. [13] 郭成豹, 刘大明. 薄钢壳物体磁特征建模研究[J]. 兵工学报, 2012, 33(8): 912-915. Guo Chengbao, Liu Daming.Modeling of magnetic signatures of thin-sheet objects[J]. Acta Armamentarii, 2012, 33(8): 912-915. [14] 朱武兵, 庄劲武, 赵文春, 等. 载体感应磁场的改进积分方程法[J]. 国防科技大学学报, 2018, 40(3): 101-106. Zhu Wubing, Zhuang Jinwu, Zhao Wenchun, et al.Modified integral equation method for carrier’s induced magnetic field solving[J]. Journal of National University of Defense Technology, 2018, 40(3): 101-106. [15] 何保委, 周国华, 刘胜道, 等. 标量磁位积分方程法计算舰艇三维静磁场[J/OL]. 兵工学报, 2022, http://kns.cnki.net/kcms/detail/11.2176.TJ.20221027.1405.004.html. He Baowei, Zhou Guohua, Liu Shengdao, et al.Ship’s 3D magnetostatic field computation utilizing integral equation method of scalar magnetic potential[J]. Acta Armamentarii, 2022, Ship’s 3D magnetostatic field computation utilizing integral equation method of scalar magnetic potential[J]. Acta Armamentarii, 2022, http://kns.cnki.net/kcms/detail/11.2176.TJ.20221027.1405.004.html. [16] 郭成豹, 张晓锋, 肖昌汉, 等. 薄钢板船舶磁性的物理模型和数值模拟混合建模[J]. 哈尔滨工程大学学报, 2008, 29(3): 247-250. Guo Chengbao, Zhang Xiaofeng, Xiao Changhan, et al.Magnetization determination of ships made of thin steel sheets by combining the physical model and numerical calculations[J]. Journal of Harbin Engin- eering University, 2008, 29(3): 247-250. [17] 周国华, 肖昌汉, 闫辉, 等. 一种弱磁作用下铁磁物体感应磁场的计算方法[J]. 哈尔滨工程大学学报, 2009, 30(1): 91-95. Zhou Guohua, Xiao Changhan, Yan Hui, et al.A method to calculate the induced magnetic field of ferromagnetic objects in a weak magnetic field[J]. Journal of Harbin Engineering University, 2009, 30(1): 91-95. [18] Trowbridge C W.Progress in magnet design by computer[C]//Proceedings of 4th Conference Mag- netostatic Technology, NewYork, USA, 1972: 555-565. [19] Chadebec O.Modelling of magnetic field induced by shells-identification of the magnetisation application to the closed loop degaussing of a ferromagnetic hull[D]. Grenoble, France: Institut National Polyte- chnique de Grenoble, 2001. [20] Guerin S.Magnetic source identification measurement robustness and optimization- application to ship magnetization reconstruction[D]. Grenoble, France: Institut National Polytechnique de Grenoble, 2005. [21] Vuillermet Y.Closed loop degaussing applied to double hull submarine Magnetization identification from near magnetic field measurements[D]. Grenoble, France: Institut National Polytechnique de Grenoble, 2008. [22] Le-Van V.Developement of magnetostatic volume integral formulations[D]. Grenoble, France: Univer- site Grenoble Alpes, 2015. [23] Chavin-Collin G, Bannwarth B, Cavallera D, et al.An integral face formulation for thin non-conductive magnetic regions[J]. IEEE Transactions on Magnetics, 2019, 55(6): 1-4. [24] Chavin-Collin G.Identification de l’aimantation de tôles ferromagnétiques soumises à des champs magnétiques faibles et à de fortes contraintes mécaniques: application à l’immunisation magnétique des sous-marins en boucle fermée[D]. Grenoble, France: Universite Grenoble Alpes, 2020. [25] 谢德馨, 杨仕友. 工程电磁场数值分析与优化设计[M]. 2版. 北京: 机械工业出版社, 2017. [26] Le-Van V, Bannwarth B, Carpentier A, et al.The adaptive cross approximation technique for a volume integral equation method applied to nonlinear magnetostatic problems[J]. IEEE Transactions on Magnetics, 2014, 50(2): 445-448. [27] 周耀忠, 张国友. 舰船磁场分析计算[M]. 北京: 国防工业出版社, 2004. [28] 陈杰, 鲁习文. 舰船感应磁场预测的一种新方法[J]. 物理学报, 2010, 59(1): 239-245. Chen Jie, Lu Xiwen.A new method for predicting the induced magnetic field of naval vessels[J]. Acta Physica Sinica, 2010, 59(1): 239-245. [29] 裴亚杰. 电磁场积分方程自适应交叉近似算法的研究[D]. 南京: 南京邮电大学, 2011. [30] Vijn A R P J. Development of a closed-loop degaussing system towards magnetic unobservable vessels[D]. Delft, Netherlands: Delft University of Technology, 2021. [31] 何保委, 刘胜道, 周国华, 等. 基于多目标模拟退火法的垂向检测线圈改进[J]. 华中科技大学学报(自然科学版), 2021, 49(12): 46-50. He Baowei, Liu Shengdao, Zhou Guohua, et al.Improvement of vertical detecting coil based on multi-objective simulated annealing method[J]. Journal of Huazhong University of Science and Technology (Natural Science Edition), 2021, 49(12): 46-50. [32] 陈龙, 易琼洋, 贲彤, 等. 全局优化算法在Preisach磁滞模型参数辨识问题中的应用与性能对比[J]. 电工技术学报, 2021, 36(12): 2585-2593, 2606. Chen Long, Yi Qiongyang, Ben Tong, et al.Appli- cation and performance comparison of global optimization algorithms in the parameter identi- fication problems of the Preisach hysteresis model[J]. Transactions of China Electrotechnical Society, 2021, 36(12): 2585-2593, 2606. |
|
|
|