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3d mangnetic field due to heat propogation

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How do i create a 3d mangnetic field of a magnet and see how the field changes as it heats up.

Also, is there a way to show how much of the magnetic flux is cutting a coil of wire around it??

9 Replies Last Post May 8, 2011, 12:09 p.m. EDT

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Posted: 1 decade ago May 1, 2011, 6:38 a.m. EDT
its important..anyone? i need help
its important..anyone? i need help

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago May 2, 2011, 1:30 a.m. EDT
Hi

well chose MF, stationary , draw your magnet (centred at 0,0,0), surround it by a sphere of radius >3-4 times your magnet, add a 1/10 radius shell on your sphere (in v4 you have the layer) call it a Infinite Element layer, add a "Ampers's Law 2" and select the magnet. Set the Magnetic field tab to Magnetisation and type M =1E6[A/m] (or whatever you need) for one direction. Do not forget to add the material air: sigma = 1, epsilon_r=1, mu_r=1 and the magnet sigma =1, epsilon_r =1, mu_r =1.1 (or whatever material properties that fit)

Then solve, you may test with or without a Inf Elements. To integrate the flux you might either Data set cut surface and integrate over it, or you add a dummy body(ies) of "air to define your relevant surfaces, and then you might pick the boundaries and integrate over them. By the way use spherical Infinite elements! this with a sphere is not the default

But this yo should have managed by your own if you had done some of the simple examples in the Model library, no ?

--
Good luck
Ivar
Hi well chose MF, stationary , draw your magnet (centred at 0,0,0), surround it by a sphere of radius >3-4 times your magnet, add a 1/10 radius shell on your sphere (in v4 you have the layer) call it a Infinite Element layer, add a "Ampers's Law 2" and select the magnet. Set the Magnetic field tab to Magnetisation and type M =1E6[A/m] (or whatever you need) for one direction. Do not forget to add the material air: sigma = 1, epsilon_r=1, mu_r=1 and the magnet sigma =1, epsilon_r =1, mu_r =1.1 (or whatever material properties that fit) Then solve, you may test with or without a Inf Elements. To integrate the flux you might either Data set cut surface and integrate over it, or you add a dummy body(ies) of "air to define your relevant surfaces, and then you might pick the boundaries and integrate over them. By the way use spherical Infinite elements! this with a sphere is not the default But this yo should have managed by your own if you had done some of the simple examples in the Model library, no ? -- Good luck Ivar

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Posted: 1 decade ago May 7, 2011, 11:56 a.m. EDT
Thanks, I was trying really hard to understand what you wrote but I can't get it workign my model. I didn't even understand what you wrote, sorry.

But I have model made in inventor on which i want to carry out the simulation on.

The CAD model is attach. Can you please help me step by step how to perform the test?

What I want to do is simple, 400 degree celicus to be on top of the piston head. The bars sticking out in the bottom of piston are the magnets. I want to see the the change in magnetic field, flux density and strength of magnetic field about 10 centimeter away from the central axis of the pistion. I have to calculate induced voltage.

I need to test the simulation with different permanent magnets.
Thanks, I was trying really hard to understand what you wrote but I can't get it workign my model. I didn't even understand what you wrote, sorry. But I have model made in inventor on which i want to carry out the simulation on. The CAD model is attach. Can you please help me step by step how to perform the test? What I want to do is simple, 400 degree celicus to be on top of the piston head. The bars sticking out in the bottom of piston are the magnets. I want to see the the change in magnetic field, flux density and strength of magnetic field about 10 centimeter away from the central axis of the pistion. I have to calculate induced voltage. I need to test the simulation with different permanent magnets.


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Posted: 1 decade ago May 8, 2011, 2:59 a.m. EDT
Can someone please help me
Can someone please help me

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Posted: 1 decade ago May 8, 2011, 4:00 a.m. EDT
see the pic for exactly what i'm trying to do... please help me on it.
see the pic for exactly what i'm trying to do... please help me on it.


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Posted: 1 decade ago May 8, 2011, 8:58 a.m. EDT
I want to integrate the flux over the circular solid around the piston

You can see the save files below [attachment]
I want to integrate the flux over the circular solid around the piston You can see the save files below [attachment]


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Posted: 1 decade ago May 8, 2011, 11:09 a.m. EDT
I'm doing the tutorials. Ill come back if I have any problem so don't bother replyign just yet
I'm doing the tutorials. Ill come back if I have any problem so don't bother replyign just yet

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Posted: 1 decade ago May 8, 2011, 11:26 a.m. EDT
Okay,, I just to find out can I calculate the current through induction by telling comsol that the permanent magnetic is moving up and down vertical motion at lets say 20 times in a second and traveling total distance of lets say X meters in one vertical movement. So it basically travels 2 times X to complte one cycle.
Okay,, I just to find out can I calculate the current through induction by telling comsol that the permanent magnetic is moving up and down vertical motion at lets say 20 times in a second and traveling total distance of lets say X meters in one vertical movement. So it basically travels 2 times X to complte one cycle.

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Posted: 1 decade ago May 8, 2011, 12:09 p.m. EDT
actually i need help making it.. please help me
actually i need help making it.. please help me

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