强电磁干扰下引信体屏蔽效能特性

Shielding Efficiency Characteristics of Fuze under Strong Electromagnetic Interference

目的针对引信系统外壳上的开孔和贯通线引起的电磁兼容问题,分析外部强电磁干扰对引信内部的耦合规律,研究开孔参数对引信屏蔽效能的影响。方法根据麦克斯韦方程组和边界条件等经典电磁理论,利用有限元仿真分析软件,研究外部强电磁干扰下,引信上不同的尺寸的通孔对引信内部电场分布的影响,进一步提出相应的屏蔽措施。结果当引信上开20 mm孔洞时,当外界电磁波频率大于圆孔的截止频率时,引信内部电场强度最强可以达到4000 V/m,减小引信上的孔洞后,引信内部的电场强度整体下降3000 V/m左右。在使用导电橡胶填充通信孔洞后,引信内部电场强度急剧下降,增加了套管之后,腔体内部的电场强度显著降低,屏蔽效果非常显著。结论引信上的开孔的形状和大小等因素均对屏蔽效果有较大影响,在引信生产和设计中,均需采用导电橡胶填充、增加套管和多个小孔代替一个大孔等措施提高引信的电磁兼容能力。

In view of the electromagnetic compatibility problem caused by the open hole and through wire on the shell of fuze system,the work aims to analyze the coupling law of external strong electromagnetic interference to the interior of fuze,and study the effect of hole parameters on the shielding efficiency of the fuze.According to the classical electromagnetic theory such as Maxwell equations and boundary conditions,the finite element simulation analysis software was adopted to study the effect of different sizes of through holes on the fuze on the internal electric field distribution under the strong external electromagnetic interference,and the corresponding shielding measures were further put forward.When a 20 mm hole was opened in the fuze and the frequency of external electromagnetic wave was greater than the cut-off frequency of the circular hole,the strongest electric field intensity in the fuze could reach 4000 V/m.After the hole in the fuze was reduced,the electric field intensity in the fuze decreased by about 3000 V/m as a whole.After the communication hole was filled with conductive rubber,the electric field intensity inside the fuze dropped sharply,and after the sleeve was added,the electric field intensity inside the cavity dropped significantly,and the shielding effect was remarkable.The shape and size of the open hole on the fuze have great effect on the shielding efficiency.In the production and design of the fuze,it is necessary to fill the hole with conductive rubber,increase the sleeve and several small holes instead of a large hole to improve the electromagnetic compatibility of the fuze.