Ploting the magnetic field in 3D

[adbouba]

Hi,
I am a new ANSYS user and would like to simulate an electromagnetic circuit in 3D. There is a spiral coil throught which a current is flowing. The resulting magnetic plots(according to me)are not meaningfull. In fact I was expecting the magnetic vectors to agree with the "right hand rule" of electromagnetic.

As a new user, it had been long I could not do that and I will appreciate any help with that regards.

 

[logbook]

Do you mean the "right hand grip" rule where your right thumb points in the direction of the current in the wire being gripped and the fingers gripping the wire indicate the direction of the B and H fields? Maxwell’s corkscrew gives the same direction. You screw the corkscrew in the direction of the current and the rotation of the corkscrew is the direction of the field. In other words, if you had a wire going in to the plane of the page with direct current going in that direction as well, the field lines would be clockwise concentric circles.

The field of your planar spiral coil should be axially symmetric. Look at it sideways, that is at right angles to the plane of the coil. You can’t see the circular shape. Rotating the coil around its axis does not change the field pattern. Take a cross-section through the coil. You have cut the conductors at right angles. The conductors to one side of the axis have the current going into the page whereas the ones on the other side of the axis have the current coming out of the page. Depending on the direction of the current the flux will either be going in from the top and out through the bottom, or vice versa.

Draw little circles around each wire, each circle having the same diameter. Put direction arrows on each of these circles. Circles in opposite directions cancel, whereas circles in the same direction add. Thus the field will tend to run parallel along the top of the coil until the turns stop, then it will dive through the hole in the middle.

 

[CarlPugh]

?When using the right hand rule, current flows from
+ potential to - potential?

 

[logbook]

Conventional current always flows from positive to negative (or from more positive to less positive) regardless of using any other sort of rule. The right hand gripping rule also uses conventional current for the thumb direction.