Electrostatic containment of negatively charged gas

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I have a hot gas with a net negative charge that I want to keep contained using an electric field. My question is how do I calculate the electric field strength necessary, and how would one go about producing it?
 

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  • #2
Drakkith
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You cannot contain it if you have a static electric field surrounding the gas. As a particle gets closer to an edge of the containment field/vessel, more and more of the negative charge is "behind" it, counteracting the growing force from the materiel still in "front" of it. In the end this results in no net force on the gas.
 
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Yet IEF works perfectly well. Since there is no "perfect" field in existence there must be some imperfect configuration. If I were to form two electrode grids and apply a voltage between them would they form the electrostatic pressure I'm looking for?
 
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Drakkith
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Yet IEF works perfectly well. Since there is no "perfect" field in existence there must be some imperfect configuration. If I were to form two electrode grids and apply a voltage between them would they form the electrostatic pressure I'm looking for?
What is IEF again?
 
  • #5
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A typo. I meant to say IEC: Inertial Electrostatic Confinement. Two spherical electrode grids are arranged with a charged gas in the center. A current runs between them and the charge develops an electric field which contains the gas. I have since posting consulted an electrical engineer friend who suggested that I estimate the generated field from the potential difference between the two grids, and calculate pressure from the subsequent force acting on the gas. Assuming static equilibrium I can solve for the voltage from the gas temperature. Does that seem reasonable, or am I pursuing an untamed ornithoid without cause?
 
  • #6
Drakkith
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In an IEC device the inner grid is typically ATTRACTIVE to protons (positive ions). The ions are attracted to the center of the device where this grid is, and most pass through the grid, go through the center, and emerge on the other side to be slowed down and pass through once more the other way. Inside the inner grid, the protons feel no net force any direction from the grid. It is only once they get outside it that they are again attracted to it.
 
  • #7
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So if the inner grid had a positive potential the negative gas would be attracted to it and repelled from the negative outer grid?
 
  • #8
Drakkith
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So if the inner grid had a positive potential the negative gas would be attracted to it and repelled from the negative outer grid?
It would only be attracted to the inner grid. The outer grid would have no net effect for the reasons I stated above. In an IEC device, the outer grid is there to provide a place for the electrons to go when they are ionized from the gas. (I think, I could be wrong on that last sentence.)
 

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