Abstract：In magnetic field computations with linear triangular elements, piecewise constant magnetic flux densities are obtained, which are unequal over two adjacent elements. In order to compute magnetic force densities inside iron and along boundary of different media, derivatives of magnetic energy and permeability are needed. A convolution method is used to obtain smoothly distributed flux densities. Fundamental formulas for smoothing via convolutions are firstly derived, then a comparison between results of convolution by different kernel functions is made and a method to find kernel functions with required smoothness is given, lastly an application of the convolution method to compute magnetic force density inside iron is illustrated.
罗炜, 李志强, 罗应立. 用于平滑处理的卷积运算及其在有限元磁场分析后处理中的应用[J]. 电工技术学报, 2009, 24(4): 1-5.
Luo Wei, Li Zhiqiang, Luo Yingli. Smoothing Convolutions and Applications in Postprocessing of Finite Element Analysis of Magnetic Field. Transactions of China Electrotechnical Society, 2009, 24(4): 1-5.
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