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rotating field animation
Posted Nov 18, 2009, 12:11 p.m. EST 2 Replies
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Hi Everyone,
I have attached a model to this post. I try to simulate a rotating electric field produced by four electrodes arranged in a circle and powered by four sinusoidal signals in quadrature. Therefore, the boundary conditions applied to the electrode surface are electric potentials respectively equal to :+5, 5*i,-5,-5i, and I allow complex numbers in the solver parameters. I have also chosen a time-harmonic analysis. The medium surrounding the electrodes is a bit conductive (not air), so I use the quasi-static electric model in the AC/DC module.
I would like to visualize the field rotation (arrow plot) with postprocessing using the "animate" menu, but no plot evolution can be observed.
I can't find where the problem lies, so any help will be very welcome!
Thanks in advance
I have attached a model to this post. I try to simulate a rotating electric field produced by four electrodes arranged in a circle and powered by four sinusoidal signals in quadrature. Therefore, the boundary conditions applied to the electrode surface are electric potentials respectively equal to :+5, 5*i,-5,-5i, and I allow complex numbers in the solver parameters. I have also chosen a time-harmonic analysis. The medium surrounding the electrodes is a bit conductive (not air), so I use the quasi-static electric model in the AC/DC module.
I would like to visualize the field rotation (arrow plot) with postprocessing using the "animate" menu, but no plot evolution can be observed.
I can't find where the problem lies, so any help will be very welcome!
Thanks in advance
Attachments:
2 Replies Last Post Nov 23, 2009, 5:25 a.m. EST
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Posted:
1 decade ago
Hi
I believe one of the issues are that the application mode selected 2D-emqvw does not allow for "harmonic" variations of the potential V, only of the current J.
By the way, on the model posted I get 3 and not 4 symmetric BC for the 5 V, this is quickly identified and fixed. But as nothing changes over time I suspect the issue as stated above.
Why not try to express the surface current instead of the boundary potential (carefull with the orientation of the "s" line vector and the arrows direction of the boundaries such to et the current to flow around correctly).
Good luck
Ivar
I believe one of the issues are that the application mode selected 2D-emqvw does not allow for "harmonic" variations of the potential V, only of the current J.
By the way, on the model posted I get 3 and not 4 symmetric BC for the 5 V, this is quickly identified and fixed. But as nothing changes over time I suspect the issue as stated above.
Why not try to express the surface current instead of the boundary potential (carefull with the orientation of the "s" line vector and the arrows direction of the boundaries such to et the current to flow around correctly).
Good luck
Ivar
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Posted:
1 decade ago
Hi Julia
I have taken some time going over your model "rotating_field", I believe the reason why you do not see it "rotate" is that you should animate the "phase" and not the time.
Try Plot Parameters - General tab - Sequence the solution at angle (phase): 0, 15, 30, 45, 60, 75, 90
just type the angles by hand and "apply" you will see your field "rotate".
In fact as you are doing a harmonic analysis you can select 1 as time (or any different from t=0) and you can visualise your rotations without necesarily going through al time steps.
For the animaton, just select any "one" time variable in the list and you will get the rotation too, you can also play with the full harmonic, half or linear to hange the render
Unfortunately COMSOL is not displaying the phase angle value in the title, not yet, have sent a sggestion to support to add this
hope this helps
Good luck
Ivar
I have taken some time going over your model "rotating_field", I believe the reason why you do not see it "rotate" is that you should animate the "phase" and not the time.
Try Plot Parameters - General tab - Sequence the solution at angle (phase): 0, 15, 30, 45, 60, 75, 90
just type the angles by hand and "apply" you will see your field "rotate".
In fact as you are doing a harmonic analysis you can select 1 as time (or any different from t=0) and you can visualise your rotations without necesarily going through al time steps.
For the animaton, just select any "one" time variable in the list and you will get the rotation too, you can also play with the full harmonic, half or linear to hange the render
Unfortunately COMSOL is not displaying the phase angle value in the title, not yet, have sent a sggestion to support to add this
hope this helps
Good luck
Ivar