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MHD

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I am working with magnetohydrodynamics.
I have to simulate a conductive fluid which is stationary at first. There are 4 magnets under the fluid. AC Electric current of 0.1Hz frequency is passed through the fluid. The fluid begins to move, and it oscillates as the current changes direction. How do I simulate this? Which physics do I use? Since the magnetic field is constant (permanent magnets), do I just need to add a source term in the NS equation? How do I do that? and since the lorentz force is J x B, how do I bring in current density into the picture? I know the conductivity of the fluid (salt concentration), I know the voltage I am applying.
Can I simulate that?

3 Replies Last Post 18.06.2017, 15:01 GMT-4
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Hello Madhura Gurjar

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Posted: 8 years ago 23.05.2017, 08:06 GMT-4
You need the Magnetic Field (mf) interface from AC/DC (it gives you Maxwell's equations) and a Single Phase Fluid (spa) interface (which gives you Navier-Stokes' equations). Then you can couple them through the volume force, saying that those forces are the Lorentz forces.
You need the Magnetic Field (mf) interface from AC/DC (it gives you Maxwell's equations) and a Single Phase Fluid (spa) interface (which gives you Navier-Stokes' equations). Then you can couple them through the volume force, saying that those forces are the Lorentz forces.

Nirmal Paudel Tribhuvan University/Electrical Engineering

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Posted: 8 years ago 24.05.2017, 09:47 GMT-4
Hi,

The following example on induction pump might be useful here.
www.comsol.com/model/inductive-liquid-metal-pump-5907

Best Regards,
Nirmal
Hi, The following example on induction pump might be useful here. https://www.comsol.com/model/inductive-liquid-metal-pump-5907 Best Regards, Nirmal

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Posted: 7 years ago 18.06.2017, 15:01 GMT-4
Thank you very much about your helpful post.
Thank you very much about your helpful post.

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