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Problem with assembly: magnetic field does not change during motion (moving mesh)
Posted Jan 28, 2011, 7:26 a.m. EST Low-Frequency Electromagnetics, Mesh, Results & Visualization Version 3.5a 3 Replies
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I followed your advices in different threads, read through modeling.pdf and the tutorials, namely "generator 2D" and "generator sector dynamic".
My problem:
I have a magnetic circuit with 3 objects, one is the coil. I model a motion of the coil but at the different positions the flux in the coil does not change. The coil just "carries" the flux from the first position with it. My final goal is to simulate the induced current (density) and the changing magnetic field due to this current and eddy currents.
My model:
I start with an axial symmetry, AC/DC, quasi-statics magnetic, azimuthal induction currents. I add moving mesh (transient). The geometry consists of 2 composite objects: the inner (left) is the 1st part of the magnetic circuit, the middle is the coil with surrounding air, the outer (right) is the 2nd part of the magnetic circuit. To the coil part I apply a motion (indeed - since all parts have the same height this part moves some percent up and down then).
I created 2 pairs, both with the coil (middle) part as destination. Boundary condition of the identity boundaries is Continuity. I don't have any setup in "Options -> Identity Conditions" but I do have two Pairs each under "Physics -> Identity Pairs -> Identity Boundary Pairs" and " -> Identity Point Pairs". I don't have any integration variables.
Just according to "generator 2D" I solve the model first with setup static and then transient.
I hope you could help me with an idea what to check and maybe change.
Thanks a lot!
Clemens
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Please login with a confirmed email address before reporting spam
Please login with a confirmed email address before reporting spam
I didn't undrestand your model thoroughly but I guess you have kind of the same problem as I had before. My model is similar to yours except instead of working with AC/DC, quasi-statics magnetic, azimuthal induction currents mode, I work in AC/DC, quasi-statics magnetic, perpendicular induction currents mode. and just like you I add moving mesh (transient).
I solved my problem with applying some changes in my model settings as following, mybe these considerations will help you too:
Physics -> Identity pairs -> Identity boundary pairs:
Under “Advanced”, make sure that for both pairs, all the frames are set to “Frame(ale)”
AC/DC-> quasi-statics magnetic, perpendicular induction currents :
Physics -> Properties :
- weak constraints : “on”
- analysis type : “transient”
Multiphysics -> Application mode ALE :
Physics -> Properties :
- weak constraints : “on”
- analysis type : “transient”
Reset model to clear previous solutions (File -> Reset Model)
Keep me informed about the progress and I hope it helps,
cheers,
Azar