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Menaus Feb4-13 12:31 AM

Questions about electrostatic charge
 
Can one transmit electrons to create an electrostatic charge through electrostatic induction?

Can one use a gas to create an electrostatic charge in an item by moving the air next to it?

If either of these are true, would it then be possible to create an effecient (I.E. one without directly touching parts) electrostatic engine/turbine, respectively?

Bobbywhy Feb4-13 04:05 AM

Re: Questions about electrostatic charge
 
Menaus,

Yes, many electrostatic generators use induction to store charge. Influence machines operate by electrostatic induction to convert mechanical work into electrostatic energy by using a small initial charge which is continually being replenished and reinforced. See: http://en.wikipedia.org/wiki/Electrostatic_generator

Gas has not normally been used as a charge transporter because it does not easily carry free electrons. Air mixed with smoke has been tried in Van de Graff-like generators using the smoke particles to carry the charge instead of the latex rubber belt. Poor efficiencies resulted in the abandonment of this method.

Liquids have performed at higher efficiencies. In initial experiments on a liquid-filled generator, voltages up to 70 kV have been achieved. The liquid dielectric is pumped around a closed-loop system and acts both as a charge-transporting medium and an insulator. The charge is injected into the liquid from field-emitting electrodes. (Can’t locate the reference now...will try again.)

For theory of operation and how to build a frictional (HV) generator see: http://www.alaska.net/~natnkell/staticgen.htm

The National High Magnetic Field Laboratory has several interactive tutorials for electrostatic generators and associated apparatus:
http://www.magnet.fsu.edu/education/...tor/index.html

Here is a long list of DIY electrostatic projects: http://amasci.com/static/electrostatic1.html

Will you please be more specific about what you propose to drive: "engine/turbine"?? Be advised, HV static generators do not produce significant amounts of power.

Cheers,
Bobbywhy

Menaus Feb4-13 06:50 PM

Re: Questions about electrostatic charge
 
By engine and turbine I mean this:

If it is possible to create an electrostatic dynamo by the movement of air or electrostatic induction, then the inverse should also be true. By Newton's third law of action/reaction, it should then be possible to create an engine from a motor working on electrostatic induction principles by operating the engine backwards. Naturally, this also means that if you use a moving dielectric such as a gas or liquid to produce electrostatic charge, then you should also be able to use electrostatic charge to move said dielectric by reversing the operation of the turbine.

This is usually true for all engines/motors/turbines, correct me if I'm wrong.

Bobbywhy Feb4-13 09:00 PM

Re: Questions about electrostatic charge
 
Menaus,

Thank you for your elaboration concerning your project. You are correct.
Electrohydrodynamics (EHD) deals with the effect of fluid motion on electric fields and the influence of the fields on the fluid motion. The basic principles of EHD describe how electrical energy can be converted directly into kinetic energy, and the reverse, kinetic energy can be converted to electrical energy.

Here are some examples from Wikipedia:
“EHD covers the following types of particle and fluid transport mechanisms: Electrophoresis, electrokinesis, dielectrophoresis, electro-osmosis, and electrorotation.”
http://en.wikipedia.org/wiki/Electrohydrodynamics

Here is one textbook that seems to offer a good introduction:
http://books.google.com/books?id=NsB...=0CDAQ6AEwADgK

If you have any doubts or specific questions, please return here to Physics Forums and post them.

Cheers,
Bobbywhy

Menaus Feb4-13 09:47 PM

Re: Questions about electrostatic charge
 
Thank you very much, although I am very much at the theoretical stage at this point. I do not however, want to create a electrostatic engine, I am only doing research for a future project. I will hint that it does not only include the idea of electrostatic generation of electricity and the inverse.

:)


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