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Problems with Magnetic force

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Hi! I am new to COMSOL and I really need some help please.

I want to study an electromagnetic actuation system to guide magnetic microparticles in blood vessels. For that I used the AC/DC module to build some coils to generate a gradient magnetic field and then I used the Fluid Flow module to model the blood. The final goal is to use the Particle Tracing for Fluid Flow module to determine the trajectory and velocity of the particles when subjected to the magnetic force, however when I include the Magnetophoretic Force (already included in the module) nothing happens! There is no change in particle velocity.

As it can be read in COMSOL: “The Magnetophoretic Force causes motion of permeable particles toward regions where the magnetic field is stronger. The magnetophoretic force is applicable for particles which are charge neutral and have a different relative permeability than the background fluid.”

But even when I insert a high value of particle relative permeability (400000) nothing happens. I was expecting a change in particle velocity. I attach some pictures of my problem.

Maybe it's something pretty obvious, but I really need some help here. Thank you!

Best regards,
Patrícia


5 Replies Last Post 29.06.2016, 23:47 GMT-4
Edgar J. Kaiser Certified Consultant

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Posted: 1 decade ago 02.04.2014, 10:59 GMT-4

Patricia,

the vessel is in the most homogeneous part of the field. You might try to place it at some location with a larger gradient.

Cheers
Edgar

--
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Patricia, the vessel is in the most homogeneous part of the field. You might try to place it at some location with a larger gradient. Cheers Edgar -- Edgar J. Kaiser emPhys Physical Technology http://www.emphys.com

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Posted: 1 decade ago 02.04.2014, 11:40 GMT-4
Thanks for the reply!
Unfortunately I already tried to place the vessel in many other locations. Also, I tried other types of coils achieving high gradients. It doesn’t matter what I do, it always ignores the existence of the magnetic field. I don’t understand what I’m doing wrong. Any other idea of what could be the problem?

Thank you very much
Thanks for the reply! Unfortunately I already tried to place the vessel in many other locations. Also, I tried other types of coils achieving high gradients. It doesn’t matter what I do, it always ignores the existence of the magnetic field. I don’t understand what I’m doing wrong. Any other idea of what could be the problem? Thank you very much

Edgar J. Kaiser Certified Consultant

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Posted: 1 decade ago 02.04.2014, 14:04 GMT-4

Patricia,

I am sorry, I don't have the Particle Tracing and Flow modules. So I can't comment on that part.

Good luck,
Edgar

--
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Patricia, I am sorry, I don't have the Particle Tracing and Flow modules. So I can't comment on that part. Good luck, Edgar -- Edgar J. Kaiser emPhys Physical Technology http://www.emphys.com

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Posted: 1 decade ago 04.04.2014, 02:32 GMT-4
Patricia,

Can you attach the model to have a look?

Regards,

Ion
Patricia, Can you attach the model to have a look? Regards, Ion

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Posted: 8 years ago 29.06.2016, 23:47 GMT-4
I think that the problem is magnetic field gradient. It didn't exist in tracking model. My simulation is the same. If you can solve, plz help us.
Thanks
I think that the problem is magnetic field gradient. It didn't exist in tracking model. My simulation is the same. If you can solve, plz help us. Thanks

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