The affect of different plasmas on each other

[dougettinger]

What occurs if a higher velocity, denser plasma plowed through a less dense plasma traveling at a lower, but parallel velocity ? Do mutual magnetic or electric inductances between the two plasmas occur ?

Regards, Doug Ettinger

 

[dougettinger]

I am drawing another blank. Can anyone tell me what industries deal with high density plasmas? Thanks.

Ionizingly, Doug Ettinger

 

[Bobbywhy]

Too bad, after some searching I could find no information on plasma-plasma interactions. However there is lots of material on plasma interactions with lasers, charged particles, planets, and more. To model plasma-plasma interactions MHD simulations may adequate.

"Because plasmas are conductive and respond to electric and magnetic fields and can be efficient sources of radiation, they are used in a large number of applications where such control is needed or when special sources of energy or radiation are required. The topics page provides close to 200 subject areas in plasma science and technology and nearly 100 applications!" (Many tutorials, too!)
http://www.plasmas.org/plasma-physics.htm

"Lodestar Research Corporation is a small business located in Boulder, Colorado specializing in applied plasma physics research. Currently, our work emphasizes applications of plasma physics to controlled thermonuclear fusion."
http://www.lodestar.com/

Two other groups that do plasma research:
http://www.mpq.mpg.de/lpg/index.html
http://www.cels.anl.gov/events/meetings/discovery/wave-plasma.htm

Lastly, you may check on UCLA's plasma research group. Some innovations and discoveries have been found by that team.

 

[dougettinger]

Thank you, Bobbywhy, for your honesty and truly helpful information.

Ionizingly, Doug Ettinger

 

[cmb]

That's a big topic you've stumbled into there, Doug! Indeed, MHD is the topic you are going to have to plough into to find your answers.

Just as a suggested starting point, try looking up 'Tri-Alpha' who are aiming to collide plasmas for fusion energy purposes. I'm not mentioning them because I think it is a good prospect for fusion energy (I've no opinion - maybe no worse nor better than other attempts) but merely because colliding plasmas is what they do so you can expect any literature they are putting out will contain references to such physics, and that might be of use.

http://pop.aip.org/resource/1/phpaen/v18/i5/p056110_s1

(PS '...effect...' ;) )

 

[dougettinger]

Thanks for your help, cmb.

Ionizingly, Doug Ettinger

 

[MikeBH]

I have never seen an application with colliding plasma. High density plasma are used in industry. These are used in fusion but also in ion sources. I have worked with a dual plasma where you form a hot dense plasma inside a magnetic field and allow it to diffuse across the magnetic field. In the hot or driver region the plasma has a hot electron temperature and the plasma is dense. On the other side of the trasverse magnetic field the plasma is less dense and the electrons are cooler. This is called a tandem source and is good for making negative ions.
http://lss.fnal.gov/archive/2005/pub/fermilab-pub-05-094-ad.pdf
The hot region forms lots of excited species which cross the magnetic field because they are neutral, and in the cold electron region negative ions are formed and there is no hot electrons to knock off the electron from the negative ion.
A hot plasma mixing into a cold plasma is very common and well understood.

 

[chrisbaird]

When different density plasmas interact, you get surface interface effects similar to when different density, non-mixing, liquids interact. For example, in the ionosphere after sunset, high density plasma up high falls into lower-density-plasma down low and you get pluming/fingering effects.