17.1.2 Demag specification

Demag Type: Specify algorithm and demagnetization kernel used to calculate self-magnetostatic (demagnetization) field. Must be one of

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  ConstMag: Calculates the average field in each cell under the assumption that the magnetization is constant in each cell, using formulae from [23]. (The other demag options calculate the field at the center of each cell.)

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  3dSlab: Calculate the in-plane field components using offset blocks of constant (volume) charge. Details are given in [3]. Field components parallel to the $z$-axis are calculated using squares of constant (surface) charge on the upper and lower surfaces of the sample.

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  3dCharge: Calculate the in-plane field component using rectangles of constant (surface) charge on each cell. This is equivalent to assuming constant magnetization in each cell. The $z$-components of the field are calculated in the same manner as for the 3dSlab approach.

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  FastPipe: Algorithm suitable for simulations that have infinite extent in the $z$-direction. This is a 2D version of the 3dSlab algorithm.

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  None: No demagnetization. Fastest but least accurate method. :-}

All of these algorithms except FastPipe and None require that the Part Thickness (cf. the Part Geometry section) be set. Fast Fourier Transform (FFT) techniques are used to accelerate the calculations.