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Ionizing air 1

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seek

Automotive
Mar 5, 2001
11
Can anyone advise on methods, techniques or tricks in "how to ionise air"? Books, articles or direct advice would be appreciated. I have posted this thread here as you guys seem to have a handle on gases and ionization.

Thanks
Seek
 
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For what purpose do you want to ionize air? Air can be ionized by gama radiation, x-rays, and ultraviolet light. The most common method is by using high voltage. Air ionizes above a certain electric field strength (volts/meter). If you apply a high voltage between two electrodes where one is a needle point or fine wire and the other electrode is a large plate or cylinder you will get a corona discharge (ionization) around the small electrode. The electric field strength is non-uniform and strongest at the small electrode. Between two plates the electric field strength would be uniform and ionization would result in an arc.

 
Thank you for your reply.

I am more interested in using the high voltage technique. What kind of ionisation rates can be achieved with the applied voltages. Do these ionised states last. I would imagine that the airs' contact with the surrounding vessel causes the ions to discharge.
 
Ions in air will be attracted to grounded conductors or oppositely charged ions creating an "ionic breeze". Ungrounded conductors will become charged and then repel any more ions.

The only limit on ionization rate is the size of your power supply and the heat, ozone, and nitrogen oxides that are generated. Ozone and nitrogen oxides are very toxic and irritating.
 
Check out the work done by Jean-Louis Naudin. He has extended the work done by Beafield and Brown on ionisation thrust, and has even published some model designs. It's all on the web.

Y'aint gonna replace wings an' rockets with it though - it's a very inefficient method of thrust. As I understand it USAF is currently researching using the method to ionise wing leading edge airstreams. The idea is to guide the air ahead of supersonic shock waves around the wing - objective being to eliminate sonic boom for stealth. Kinda pointless when the thang glows in the dark...

"If it's gravity your trying to overcome, it's gravity you have to understand"

Mart
 
There is an ongoing project, Ajax, that will accomplish this. The project is an answer to the Russians whom the Swedish Air Force has supposedly tracked on radar at 12X and bursts to 16X. The introduction of ionized gas at the front of the air plane is augmented by a MHD device in the fuselage of the airplane.
 
Interesting, any links?

I take it that the the leading edge of the wing/nose is charged to the same polarity as the ionised air. Most research is, i assume, directed to charge distribution to get the correct airflow. Must guzzle power, but less than AB - Clever system. I hadn't realised 16X was possible! This'll just about allow a craft to go ballistic - purpose of the X original craft. Doesn't this kind of negate the record held by the X-15?

Mart
 
I first saw references to the plane/propulsion system on the Science Channel and found a couple of references to it, both links are now dead and you get the ubiquitous do you want to buy this domain name. The name mention on the Science Channel was Paul Czysz. It is interesting that his name surfaces in comments on the Columbia Disaster.
The first link is to some papers on the possibility of MHD on Super/Hypersonic propulsion systems. The other two are rather interesting at times and hoping to get something on this.
Anecdotal:
The system shown on TV caught my eye as about 25 years ago I had some information on a system that could be purchased called “E-Beam”, not the welding variety, that was an extremely high voltage system that we looked at because it could cool a hot surface, weird. I turned the information over to our research group and forgot about it. About 18 months later I was asked to work on a project that would involve the system. At that time the company disappeared completely.




 
Interesting stuff unclesyd - Scotland eh? ;-) Must admit I still see any propulsion system based on change of momentum as fundamentally limited - regardless of how technically advanced. For one thing it only works as long as there is a medium to have it's momentum changed - bit of a pain when that medium is also the cause of drag!

I am (slowly due to lack of funds) working on my own solution to the problem. My motive is more for facilitaion of mass transport, but the conspiracy stuff is great fun! Do you think we are likely to see a practical successor to the jet in the near future then?

Sorry if this is wondering off your thread, seek. I'm kinda guessin' this is the sort of application you had in mind...

Mart
 
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