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Dielectric oil flow

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Adam Munich

Mon Jan 24 2011, 06:53PM

Registered Member #2893 Joined: Tue Jun 01 2010, 09:25PM
Location: Cali-forn. i. a.
Posts: 2242

Nothin' special.

Patrick

Mon Jan 24 2011, 07:29PM

Registered Member #2431 Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639

This is definately the ion wind effect... though the second video is a special case.
charge carriers present in the oil are being influenced as:

F=(I x D)/K

Where:
F equals force in newtons.
I equals charge in amps (within the oil only)
D equals distance in meters ( of the non uniform field path)
K is a constant for each liquid or gaseous medium. (Ion Mobility--in meter^2 volt-seconds) also relates to velocity of stream.

ion flight time is:

W = (K x V)/D

where:

im late gotta go!!

Thus this is an electrokinetic pump or electrokinetic rocket in the case of my Ph.D thesis (DeSeversky type)
it is bazarre and cool, even scary and yes Grenedier when you increase the voltage you get a nonlinear response (it increases to a torrent as V goes up, as you said). The above formula can be applied to approximate this nonlinear response too, remember increase V and you increase I, V x I = energy, thus the graph of a general case of the ion wind intensity is a rising curve (rises upward along Y-axis, but the X-axis units increase to the right less fast than the y units, as in e^x)

Dam it ive got EECE-434 class now, ive got to go but have more to say.

Ok one more point, the "I" and "D" pertain to the individual charge carriers (someone mentioned water vapor, and another said molecular oil fragments. Yes, I think both.) The "K" part of the equation is an empiracal average (Ion Mobility) for how few charge carriers can influence how many neutral molecules. Thus the velocity of the major flow, is always less than the velocity of the minor (charge carrier stream) flow. Motion caused by the minor flow is fast, low mass, and this inertia is transfered to many more molecules at reduced speed, thus conservation of momentum, charge and energy still remain intact.

Now i Gotta go!!!

P.S.> Believers in electrogravitics, anti-gravity.... bite me, its ion wind

Ash Small

Tue Jan 25 2011, 01:24AM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

Is this not something to do with polar properties of a dielectric? (see 'capacitor theory' for an explanation)

I've noticed similar effects with electro-polishing solutions containing dielectrics like ethylene glycol or glycerine (glycerol).

Mattski

Tue Jan 25 2011, 04:55AM

Registered Member #1792 Joined: Fri Oct 31 2008, 08:12PM
Location: University of California
Posts: 527

The polarizability of a dielectric is what gives it a dielectric constant greater than that of vacuum. Still in a uniform electric field a dipole moment will not feel a net force once it is aligned with the field. But if the electric field is non-uniform then I think it should have a net force pushing it.

Patrick

Tue Jan 25 2011, 05:30AM

Registered Member #2431 Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639

Mattski wrote ...

The polarizability of a dielectric is what gives it a dielectric constant greater than that of vacuum. Still in a uniform electric field a dipole moment will not feel a net force once it is aligned with the field. But if the electric field is non-uniform then I think it should have a net force pushing it.

Yes, what Mattski says is right, but I dont think thats what were seeing in the video clips.

****************************************** *********************************

Ash Small wrote ...

I've noticed similar effects with electro-polishing solutions containing dielectrics like ethylene glycol or glycerine (glycerol).

I think you may be seeing the lorentz force in a conductive fluid.

When you say dielectric, do you mean an aqueous solution atleast partially conductive?

Ash Small

Tue Jan 25 2011, 05:49AM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

80% dielectric, 10% electrolyte (acid), 10% H20 (for example)

(That video has a magnet underneath the container, there were no magnets present in my setup.)

Patrick

Tue Jan 25 2011, 06:21AM

Registered Member #2431 Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639

Ash Small wrote ...

(That video has a magnet underneath the container, there were no magnets present in my setup.)

Yes Ive seen that too, I tried to find the video with two vertical poles in water and then the water flows with no magnet. I believe it is the lorentz force in both cases.

klugesmith

Tue Jan 25 2011, 05:42PM

Registered Member #2099 Joined: Wed Apr 29 2009, 12:22AM
Location: Los Altos, California
Posts: 1716

Same effect was discussed here, at length, almost a year ago:

How about comparing the thrust of a high voltage "lifter" in air
to that of same apparatus as a submarine in oil?

Patrick

Tue Jan 25 2011, 06:27PM

Registered Member #2431 Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639

Grenadier wrote ...

I don't think it's entirely that because the flow is petty substantial, and it becomes vigorous at higher voltages. At 70kV it's like a torrent. It'd take a lot of ions for that to happen, and if the oil was that conductive the multiplier would likely fail.

The ion wind effect is based on the premise that the medium not be conductive, else the ion wind no longer exists. It is the non-conductivity (high resistivity) of the oil that allows chrage transfer to take place--a consequence of this is the molecular motion we see.

EDIT: What I mean to say is that there are essentially no freely conducted electrons moving through the oil. The molecular fragments are being charged to 1-+,2-+ ... then they act as charge carriers, like in solid semi-conductors. There can be no substantial conduction of electrons through the oil (as if the oil were a metal wire), else the ion wind effect is driven to extinction.

Grenadier wrote ...

Gahh PM got a ninja post in...
Then how does that explain this?

" Plateau-Rayleigh instability" of liqiud jets explains why the needle can project fluid as a jet or a series of large droplets, up and out of a container, but the force/energy driving the Plateau-Rayleigh jet, is the ion wind effect, in this specific case. (There are other means HV can cause motion too, not just ion wind).

Klugesmith wrote ...

Same effect was discussed here, at length, almost a year ago:

I will read this thread in detail later.

Klugesmith wrote ...

How about comparing the thrust of a high voltage "lifter" in air
to that of same apparatus as a submarine in oil?

That can be done, also I had a high school teacher, Mr. Aweeka, who wanted me to develop the DeSeverky device into a "no moving parts fluid pump". For explosive liqiuds like gasoline this could be used in long distance pipes to pump fluids at large volumes without the need for high pressure, or I think thats what we were thinking back in 1998 ? In the absence of air this was thought to be no safety hazard.

However Acetylene is a gas/liquid of special circumstance, acetylene can explosively decompose due to kinetics or turbulence, then bursting out of its pipe/container then explodes/burns a second time having found air.

But oil is easier and perhaps as others here have pointed out, more cool to look at. The ground pepper is a good idea.

Patrick

Sat Jan 29 2011, 09:48PM

Registered Member #2431 Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639

Also, I see oil creeping up the black wire, thats not ion wind, but I'm thinking about whats casusing it...

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