Electrostatic containment of negatively charged gas

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Discussion Overview

The discussion revolves around the concept of electrostatic containment of a negatively charged gas, specifically focusing on the calculation of the necessary electric field strength and methods for producing it. The scope includes theoretical considerations and practical applications related to inertial electrostatic confinement (IEC).

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant inquires about the calculation of electric field strength required to contain a negatively charged gas using an electric field.
  • Another participant argues that a static electric field cannot effectively contain the gas due to the counteracting forces as particles approach the edge of the containment field.
  • A different viewpoint suggests that inertial electrostatic confinement (IEC) could work, proposing the use of two electrode grids with a voltage applied between them to create the desired electrostatic pressure.
  • A participant clarifies that IEC involves two spherical electrode grids where a charged gas is contained, and suggests estimating the generated field from the potential difference to calculate pressure on the gas.
  • Discussion includes the role of the inner grid in IEC, which is typically attractive to positive ions, and how this affects the behavior of the negatively charged gas.
  • There is a question about whether the negative gas would be attracted to the positively charged inner grid and repelled by the negatively charged outer grid, with some participants affirming this idea while others express uncertainty about the outer grid's role.

Areas of Agreement / Disagreement

Participants express differing views on the effectiveness of static versus dynamic electric fields for containment, and there is no consensus on the optimal configuration or methodology for achieving electrostatic containment of the gas.

Contextual Notes

Participants mention various assumptions regarding the behavior of charged particles in electric fields, the role of electrode configurations, and the implications of static versus dynamic fields, but these assumptions remain unresolved.

Landon
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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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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.
 
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?
 
Landon said:
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?
 
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?
 
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.
 
So if the inner grid had a positive potential the negative gas would be attracted to it and repelled from the negative outer grid?
 
Landon said:
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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