电磁脉冲对带孔缝腔体的耦合特性

Coupling Characteristic of EM Pulse into the Conductor Enclose with Aperture

利用时域有限差分方法( FDTD)研究了电磁脉冲对带孔缝导体腔的耦合特性。为减少存储空间而采用非均匀网格法,分别对腔体上开有不同形状(正方形、长方形)和不同数目孔缝时的耦合效应进行分析。结果表明,在孔洞面积相同的情况下,电磁脉冲对正方形孔洞的耦合能量较小;而对长方形,当脉冲的极化方向与孔洞短边平行时,耦合能量最大;此外,把单个孔洞分成总面积不变的多孔洞后,耦合能量减小;同时,在保持通风面积不变的情况下,将原本开在一层屏蔽板上的孔缝交错地开在两层板上,能够明显改善屏蔽效果。

Coupling characteristic of EM pulse into the conductor enclose with aperture is studied with FDTD method. To reduce the need of computer memory, the non-uniform meshes are used. The coupling results of different shapes (rectangle and square) and numbers of apertures are discussed. It shows that, for the case of the same area, the energy coupling into the square aperture is smaller than that of into the rectangular ones. As to the rectangular aperture, the coupling energy is the largest when the polarization direction is paralleling to the shorter side of the rectangular. Besides, dividing the single larger enclosure aperture into multi-apertures, keeping the total area unaltered, will decrease the energy coupling into the enclosure. If an extra screen with the same total aperture area and different aperture position is inserted behind the first one, the shielding effectiveness will be improved significantly.