I Question about magnetohydrodynamics (MHD) for electricity production

AI Thread Summary
The discussion centers on the feasibility of generating electricity using magnetohydrodynamics (MHD) by moving a magnetic field instead of charges. The proposed design involves spinning ferrite magnets in a circular motion around a plasma, with the aim of inducing an electric field. However, participants highlight that a time-independent magnetic field does not produce the necessary Lorentz force for electricity generation. The concept resembles a generator, but the lack of relative motion between the magnetic field and the charge raises questions about its effectiveness. Ultimately, the consensus suggests that without movement of charges or a time-varying magnetic field, this setup may not generate significant electricity.
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Is this design theoretically possible for electric energy production? Could be realised to be used to produce electricity?
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According to the MHD theory, is case of energy production, a magnetic appplying a magnetic field to a moving charge perpendicular to the magnetic field, that could be plasma as well a solution full of ions, and placing two plates, electricity could be produced.
Now I have a question, let's say instead of moving the charges, the magnetic field is moved, in paricular in a circular motion with two ring

magnets
Screenshot 2023-12-26 082619.png
like in the image. Let's say they are ferrite magnets, so the intesity is kinda low respect to neudium magnets. These are made spin very fast, in the same direction. Now in theory by putting the a charge in between, and I though to fire, that is a plasma, and two plates.

Could this design produce a relevant amount of electricity? Could this work?
Screenshot 2023-12-26 082619.png
 
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What is your energy source?
 
I'm not sure if I understand the concept, but it looks like you want to reproduce a generator - extracting electricity from the motion of the magnet rings? You get a force from a time-dependent magnetic field inducing an electric field, but the field here is time-independent.
 
mfb said:
I'm not sure if I understand the concept, but it looks like you want to reproduce a generator - extracting electricity from the motion of the magnet rings? You get a force from a time-dependent magnetic field inducing an electric field, but the field here is time-independent.
Yes exactly, Normally in MHD generators the hot gas is shoot in between the fixed magnetic field, but what if the plasma, in this case fire from the combustion stays in that semi-ring, and the magnets over them spins, could this setup produce electricity? In other words could moving the magnetic field like this produce the necessary lorentz force to produce electricity?
 
There is nothing moving here (besides the field source). A moving particles in a magnetic field works: In the reference frame of the magnetic field you have the particle moving, in the reference frame of the particle the field transforms to have an electric field component. But here both reference frames are identical and you only have a non-moving charge in a magnetic field, assuming perfect symmetry in the setup.
 
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