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J4  2010, Vol. 44 Issue (3): 463-467    DOI: 10.3785/j.issn.1008973X.2010.03.009
    
LI Zhongshi1, YAN Dandan1, ZHU Shanan1, HE Bin 2
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Abstract  

The magnetic field outside produced by the current dipole within a volume conductor of an arbitrary geometry was calculated by using a meshless finite element method (FEM) and BioSavart law. In order to take the advantage of BioSavart law, the current density within the whole medium has to be calculated first. According to the boundary conditions, the meshless FEM was used to calculate the potential at each node. The current density was achieved by the gradient of potential. The components of the induced field were realized by the integral of current density. The algorithm was evaluated on a singlelayer homogeneous sphere model with a satisfactory result achieved. This algorithm was also used on the hearttorso model from magnetic resonance imaging of a healthy person for the latent application on the analysis of magnetocardiogram (MCG) and magnetoencephalogram(MEG).



Published: 20 March 2012
CLC:  TP 391.9  
Cite this article:

LI Chong-Shi, YAN Dan-Dan, SHU Shan-An, Bin He. . J4, 2010, 44(3): 463-467.

URL:

http://www.zjujournals.com/eng/10.3785/j.issn.1008973X.2010.03.009     OR     http://www.zjujournals.com/eng/Y2010/V44/I3/463


基于无网格有限元方法的心磁场计算仿真研究

利用无网格有限元方法求解毕奥萨伐定律来计算电流偶极子源在任意形状均质容积导体外产生的磁场分布.通过毕奥萨伐定律计算容积导体外产生的磁场分布须先得到整个媒质中的电流密度分布,依据相应的边界条件,采用无网格有限元方法求解媒质容积导体有限元模型中各节点的电势;通过对电势求梯度得到媒质内部的电流密度分布;媒质内部感应磁场分布的各个分量可通过对电流密度进行数值积分计算来实现.为了验证提出的无网格有限元方法的有效性,在单层均质球模型上进行了仿真研究,并将该方法应用于从核磁共振成像(MRI)得到的真实形状的心脏躯干心脏模型上,取得了令人满意的计算结果,表明了算法的有效性及其在心磁图(MEG)和磁场分布(MCG)上的潜在应用前景.
关键词: 

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