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3D AC Coils with Moving Mesh

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Hi guys,

I'm trying to model a pair of coils, one active with a varying AC current and a parallel passive coil that is suppose to act like a sensor. In this model I'm sending a metallic object through the centre of the two coil and then measuring the induced current on the passive coil.

At the moment I'm having some trouble simulating the study as it's taking 5+ hours to run and I'm not sure whether the model is behaving correctly. If someone could take a look at my model and let me know if the following is correctly implemented, or if there is an easier alternative:

The AC input
The external current density, I want to apply 30A so the equation written in the parameters is I/A where is the area of the coil
The Moving Mesh physics, where the air domain and metallic object are included, with the metallic object set to have a prescribed deformation

I'm also unsure whether to apply a copper material to the coils, as I've seen in the Helmholtz tutorial, it states that the external current defines the coil, however I have one coil without anything current applied. When I do run the study without material I get the correct magnetic flux density, and when I apply copper the values are incorrect.

The study has to be time dependent as I have to observe the change in induced current in the passive coil as the object passes through the magnetic field. Also which is the best way to observe this change in induced current? using a domain point probe or evaluating a surface or volume integral in the derived values?

Thanks,
--
Ryan Mulheron


3 Replies Last Post 21 mar 2014, 05:45 GMT-4

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Posted: 1 decade ago 20 mar 2014, 06:43 GMT-4
Hi!
I would move a cylinder of air together with your projectile. I have used assembly to produce an identity pair. This pair you have to define in your physics as continuity.
I don't use infinite elements here...
Ralf
Hi! I would move a cylinder of air together with your projectile. I have used assembly to produce an identity pair. This pair you have to define in your physics as continuity. I don't use infinite elements here... Ralf


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Posted: 1 decade ago 20 mar 2014, 18:23 GMT-4
Hi Ralf,

Thanks for the reply.
Unfortunately I'm unable to open your model as I'm running version 4.1.0.88

Were you able to see any interaction or change in the field or induced voltage in the passive coil as the projectile moved through the centre?

With the help of technic support I've been able to simulate the model, however I'm still not seeing any interaction. I've tried increasing the size of the projectile to see if that changes anything but unfortunately it hasn't.

Thanks,
--
Ryan Mulheron
Hi Ralf, Thanks for the reply. Unfortunately I'm unable to open your model as I'm running version 4.1.0.88 Were you able to see any interaction or change in the field or induced voltage in the passive coil as the projectile moved through the centre? With the help of technic support I've been able to simulate the model, however I'm still not seeing any interaction. I've tried increasing the size of the projectile to see if that changes anything but unfortunately it hasn't. Thanks, -- Ryan Mulheron


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Posted: 1 decade ago 21 mar 2014, 05:45 GMT-4
Hi Ryan,
I didn't solve your complete problem. My model was just the part for moving mesh.
Sorry,
Ralf
Hi Ryan, I didn't solve your complete problem. My model was just the part for moving mesh. Sorry, Ralf

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