The formulation for the azimuthal component of the magnetic vector potential for axisymmetric magnetostatic applications is well known. However for transient magnetic fields with solid source conductors and eddy currents the formulation has to be revised. A variable transformation is introduced toremove the singularity from the numerical scheme. The numerical error cannot accumulate and is put instead to the postprocessing at every time step.

中文翻译：

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固体源导体的瞬态磁场公式

用于轴对称静磁应用的磁矢量势的方位角分量的公式是众所周知的。但是，对于具有固体源导体和涡流的瞬态磁场，必须修改公式。引入变量变换以消除数值方案的奇异性。数值误差无法累积，而是在每个时间步入后处理。