Re: [femm] PM design - Simulation results far from Prototype results....

[marctt2@xxxxxxx]

One thing that comes to mind are 3D end effects.  If you are simulating a device with radial symmetry then the field that you get will depend on how "deep" your design is into the paper.  If your design is of finite axial length, the field that you measure will be somewhat less than what 2D FEA predicts.

To me, 1.2 to 1.4T in the airgap sounds high; perhaps your steel is saturating as well, or you have incorrect models for your grade 35 NdFeB. ?

Also, the field that you measure with your Gauss probe depends on the angleof the probe tip.  If you have an angular error, the field that you read will be less than the actual field.

Regards,
Marc Thompson

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Marc T. Thompson, Ph.D.

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