In order to improve the performance of a magnetically levitated (maglev) axial flow blood pump, three-dimensional (3-D) finite element analysis (FEA) was used to optimize the design of a hybrid magnetic bearing (HMB). Radial, axial, and current stiffness of multiple design variations of the HMB were calculated using a 3-D FEA package and verified by experimental results. As compared with the original design, the optimized HMB had twice the axial stiffness with the resulting increase of negative radial stiffness partially compensated for by increased current stiffness. Accordingly, the performance of the maglev axial flow blood pump with the optimized HMBs was improved: the maximum pump speed was increased from 6000 rpm to 9000 rpm (50%). The radial, axial and current stiffness of the HMB was found to be linear at nominal operational position from both 3-D FEA and empirical measurements. Stiffness values determined by FEA and empirical measurements agreed well with one another. The magnetic flux density distribution and flux loop of the HMB were also visualized via 3-D FEA which confirms the designers' initial assumption about the function of this HMB.

中文翻译：

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通过 3-D FEA 优化磁悬浮血泵的混合磁轴承

为了提高磁悬浮 (maglev) 轴流血泵的性能，使用三维 (3-D) 有限元分析 (FEA) 来优化混合磁轴承 (HMB) 的设计。使用 3-D FEA 包计算 HMB 多个设计变体的径向、轴向和电流刚度，并通过实验结果进行验证。与原始设计相比，优化后的 HMB 具有两倍的轴向刚度，由此产生的负径向刚度的增加被增加的电流刚度部分补偿。相应地，磁悬浮轴流血泵的性能经过优化的 HMB 得到了改进：最大泵速从 6000 rpm 提高到 9000 rpm（50%）。径向，根据 3-D FEA 和经验测量，发现 HMB 的轴向和电流刚度在标称操作位置是线性的。由 FEA 和经验测量确定的刚度值彼此非常吻合。HMB 的磁通密度分布和磁通回路也通过 3-D FEA 进行了可视化，这证实了设计人员对该 HMB 功能的初步假设。