基于超收敛点的应力恢复方法提高场强计算精度

Improving the Accuracy of Numerical Solution of Intensity of Electromagnetic Field Based on Superconvergent Patch Recovery

将力学中基于超收敛点的应力恢复方法(SPR)应用到电磁场问题中,可以有效地克服三角形三节点有限元法在计算场强时精度较低的问题.通过对单元中超收敛点上场强的插值,可以得到区域内任意一点的高精度场强.针对不同媒质分界面和不同的边界条件,提出了相应插值处理方法,利用该方法求解了接地金属槽和电缆附件的电场分布.结果表明,该方法可以大幅度提高场强的计算精度.

To overcome the shortage of less accuracy in field calculation by finite element method (FEM) with triangular elements of linear type, the superconvergent patch recovery method, which is usually applied to mechanics, is introduced into electromagnetic problems. By interpolation of the field intensity at superconvergent nodes, the electric field intensity at any point can be derived more accurately. Aimed at the individual multimedia interface characters and various boundary conditions, the corresponding interpolation methods are presented. The proposed method is adopted to calculate the field distribution of a grounding metallic groove and a cable accessory. The results in dicate that the above mentioned method possesses numerically higher accuracy and can meet the demand for engineering application.Keyworkds:finite element method;superconvergent;accuracy;error