一种考虑小孔尺寸效应的孔阵等效建模方法

An equivalent approach to modeling aperture array with considering size effect of apertures

对带孔阵腔体的电磁屏蔽特性进行数值计算时,为减少模型网格数量并降低孔阵建模复杂度,提出一种考虑小孔尺寸效应的孔阵等效建模方法.首先将孔阵等效为面积相同的单孔,然后根据孔数量对单孔尺寸进行缩小.利用孔阵导纳理论和数值仿真拟合方法分别建立缩小比例与小孔数量的关系,对比得出拟合方法得到的缩小比例公式精度较高的结论.通过改变干扰源、监测点位置、孔阵面积、孔阵位置、小孔形状及腔体尺寸等参数,验证了等效方法的适用性.孔阵等效建模方法能在保证仿真精度的前提下显著减少网格数量,可为大型复杂腔体屏蔽特性的数值计算提供一种有效的简化手段.

In order to reduce the number of numerical meshes and simplify aperture array modeling, an equivalent method of modeling aperture array in which the size effect of apertures is taken into account, is presented in the paper. In this method, the aperture array is replaced by a single aperture which has the same area as the original aperture array, then the scaling factor of the aperture is obtained according to the number of apertures. The empirical relations between the number of apertures and scaling factor are proposed based on theoretical derivation and curve fitting method respectively. The comparison with the commercial software HFSS indicates that the formula based on curve fitting method has a higher accuracy. The applicability of the method is verified by varying the interference source, monitoring point, total area and position of aperture array, shape of aperture and cavity size. As shown by the numerical results, the equivalent modeling approach can significantly reduce the number of meshes, which can serve as a simplified approach to numerical simulation of shielding characteristics of complex cavity.