Re: [femm] Re: Incorrect force direction

["Greg Watson" <gowatson@xxxxxxxxxxxxxxx>]

----- Original Message -----
From: "Rob " <rtickle@xxxxxxxx>
To: <femm@xxxxxxxxxxx>
Sent: Sunday, December 31, 2000 7:46 PM
Subject: [femm] Re: Incorrect force direction


> Also noticed that if you take away the bottom steel bar, the force
> is correctly calculated to be positive rightward, so it's something
> about the 2nd bar being there...

Hi Rob,

I believe the problem is that FEMM is not taking into consideration the variable
working point on the bars B/H curve as it calcs the field contours in the air
between the magnet & the bar. The working point increases going from the left
side above the magnet, to the right side above the magnet due to flux bunching
from the flux being forced to make a abrupt turn to the right.

Greg