摘要
为简化等几何分析中多种场约束的添加问题,提出一种等几何配点法,并将其应用于电磁涡流场问题.针对磁矢位散度为零的条件、未来形状优化需求及电磁力后处理需求,在求解过程中取4个措施:(1)将高斯积分点选为配点;(2)应用BEM-FEM耦合方法的变形形式来处理电磁场外边界;(3)将多出的配点方程看做约束;(4)应用QR分解法求解所形成的过约束矩阵方程.数值算例结果表明,该方法适用于多种约束下的偏微分方程求解问题.
In order to simplify the process of imposing multiple constraints in Isogeometric analysis(IGA),an IGA collocation method for solving PDEs is established and applied on the eddy current problems. Considering the divergence-free property of the magnetic vector potential, the shape optimization in the future research and the electromagnetic force calculation in the post process, four technologies are used in the analysis process:(1) selecting the Gaussian points as the collocation points,(2) utilizing an equivalent form of the BEM-FEM coupling method to deal with the magnetic boundary conditions,(3) seeing the additional collocation equations as restrictions, and(4) applying the QR-decomposition method to solve the over-constrained matrix equations. Numerical results show that the presented IGA collocation method is available to solve the PDEs under over-constraints.
引文
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