How do ionic wind Lifters really work?

  • Thread starter Omegatron
  • Start date
  • #1
Omegatron
68
2
So I've read about these Lifters that lots of crazies attribute to antigravity or whatever. Obviously we know that it's caused by the ionic wind.

But how does that work, exactly?

One description I read says that the high voltage of the top conductor ionizes air (by removing or adding electrons?), which is then attracted to the bottom conductor. On its way to the bottom conductor it collides with neutral air molecules, and imparts momentum to them. The neutral molecules are not attracted to the conductor, so they just keep on moving in the same direction, creating the wind. The charged particles keep going until they hit the bottom electrode, give up their charge, and become free-floating neutral particles again.

(If this is the correct way to think about it, how is power transferred from the source to the load? What effect does the change in momentum of the moving particles have on the electrical properties of the air? Do the collisions look like added resistance to the circuit? Could you stop the air from moving and see a change in resistance?)

They say that the lifters don't work as well if they're arcing, which would seem to mean that the corona discharge works better because the charged particles are more dispersed and interact with neutral air molecules more often, so this description makes sense to me.

Another description seems to say that the force seems to come from neutral air molecules becoming polarized and attracted to the top conductor, then being repelled from the bottom conductor. Is this really just the same thing as above? It almost looks like it's supposed to be expelling a constant stream of negatively charged ions, which can't possibly be true, can it? The lifter and power supply would then become more and more positively charged, and the negative particles would flow right back.

Things like this and those "ionic breeze" air "purifiers" claim that they release ions into the general atmosphere surrounding the unit. But is that really true? Wouldn't the ions just travel from one electrode to the other? Maybe they really mean the byproducts of ionization like ozone...

Also, stop calling them "asymmetrical capacitors". Capacitors have this thing called an insulator between the two plates that prevents charge from flowing. Ionized air is not an insulator.

I saw this in a related thread from 2004:

And yes, we have to deal with the constant barrage of crackpots here, but we do our very best to eliminate bad posts quickly.

That's a really awful attitude. Don't censor it; debunk it. Otherwise they'll never learn and keep coming back.

Haven't you ever been to a crackpot website? "Go to our website to find out what They don't want you to know!!!" Censoring them just makes them even more crazy.
 

Answers and Replies

  • #2
pallidin
2,209
2
Omegatron said:
Also, stop calling them "asymmetrical capacitors".

Why? They ARE asymmetrical.
 
  • #3
Omegatron
68
2
pallidin said:
Why? They ARE asymmetrical.

I never said they weren't.
 
  • #4
pallidin
2,209
2
The ultimate test of the "Lifter" would be in a vacuum.
 
  • #5
Omegatron
68
2
pallidin said:
The ultimate test of the "Lifter" would be in a vacuum.

Yeah. They've been tested in vacuum and they don't work.

As I showed in one of my links...
 
  • #6
pallidin
2,209
2
Omegatron said:
Yeah. They've been tested in vacuum and they don't work.

As I showed in one of my links...

I would suppose,then, that the "Lifter" device primarily operates under ionic wind dynamics.
 
  • #7
Omegatron
68
2
pallidin said:
I would suppose,then, that the "Lifter" device primarily operates under ionic wind dynamics.

Yep. As I said.

So how do ionic wind dynamics work?
 
  • #8
pallidin
2,209
2
It seems like your first description in your original post is essentially correct, though I am no expert.
What I do know is that the top wire of the "Lifter" ionizes the surrounding gasous environment, and that the bottom, oppositely charged "electrode" section of the Lifter is electrically attracted towards that upper ionized environment, resulting in movement of both the lifter and the ionized gas.
 
  • #9
pervect
Staff Emeritus
Science Advisor
Insights Author
10,165
1,326
There's a simpler somewhat different version of dipole explanation that I think is likely to explain the lifter. Ionization is not necesarily involved.

If you have a dipole

-+

the force on the dipole is proportioanl to the rate of change of the electric field. This is because the total force on the dipole is E(right)*q - E(left)*q. If E(right), the electric field on the right side of the dipole = E(left), there is no force. This is true for a uniform electric field. If the field is not uniform, however, there is a force on the dipole, which is proportional to the rate of change of the field strength.

The assymetrical capacitor will generate an electrical field with a gradient. (It will be stronger near the small plate, and weaker near the large plate).

This is not true of a symmetrical capacitor, which will generate a uniform field between the plates.

So we would expect an induced dipole moment on the air, and the induced dipoles should follow the electric field gradient- but only with an assymetrical capacitor.

To test whether this proposed explanation actually is correct would need some experimental verification.
 
  • #10
Ivan Seeking
Staff Emeritus
Science Advisor
Gold Member
8,010
1,004
That's an interesting point, pervect.
 
  • #11
Omegatron
68
2
pallidin said:
What I do know is that the top wire of the "Lifter" ionizes the surrounding gasous environment, and that the bottom, oppositely charged "electrode" section of the Lifter is electrically attracted towards that upper ionized environment, resulting in movement of both the lifter and the ionized gas.

I don't think that's correct. That strikes me as perpetual motion machine thinking. Hmm...

pervect said:
the force on the dipole is proportioanl to the rate of change of the electric field. This is because the total force on the dipole is E(right)*q - E(left)*q. If E(right), the electric field on the right side of the dipole = E(left), there is no force. This is true for a uniform electric field. If the field is not uniform, however, there is a force on the dipole, which is proportional to the rate of change of the field strength.

Doesn't seem right to me, either.

The assymetrical capacitor will generate an electrical field with a gradient. (It will be stronger near the small plate, and weaker near the large plate).

It won't be any stronger, it will just be "less dense". The field lines would be spaced farther apart in some regions and closer together in others. I wish I remembered my electromagnetics... I'll dig out my books if I have to. :-)

So we would expect an induced dipole moment on the air, and the induced dipoles should follow the electric field gradient- but only with an assymetrical capacitor.

Highly skeptical. :-) I don't think there really is such a thing as an "asymmetrical capacitor". Think about it this way. Put two metal plates very close to each other in a typical capacitor situation. Now imagine a variable capacitor, in which the plates slide so that less of them is facing each other. The "overlap area" becomes less for both plates. Now imagine the same thing with one smaller plate on top of one bigger plate. The area directly across from the smaller plate acts as a capacitor, while the extra non-overlap isn't really part of the capacitor. I know this is an oversimplification and hard to explain, but I don't think the "asymmetrical capacitor" is right at all.

To test whether this proposed explanation actually is correct would need some experimental verification.

What would you propose for a test? Immerse it in a material that has all qualities (viscosity, etc.) equal, but with differing tendencies of the molecules to form dipoles? Testing with and without corona discharge?
 
  • #12
Adzoe
3
0
Posters here seem to operate as though this subject exists in a vacuum. Ionic wind is a well known phenomenon that is currently exploited in an ever increasing range of products and with ever improving efficiency. View, for example, the 8 patents of Krichtafovitch assigned to Kronos Air Technologies, which uses them to move up to 20,000 CFM at speeds up to 1500 FPS.

Regarding the lifter in an "hermetically sealed" environment, hermetic sealing refers to movement of solids, fluids and gasses. It does not affect, for example, radiations, magnetism, or in this case capacitance. In fact, the plastic film making the hermetic package is a well known dialectric useful for capacitance. Imagine charges at opposite ends of that dialectric having charges in the tens of thousands of volts potential. The air outside that film will be electrically charged with potentials having somewhat lower values. Those potentials will be fully capable of generating an ionic wind effect on the outside of the system.

To properly test this hermetic seal it would have to be surrounded by an electric shield of very low resistance that also had a near zero resistance and inductance to ground. Such a test hs not been done.
 
Last edited:
  • #13
Omegatron
68
2
Adzoe said:
Posters here seem to operate as though this subject exists in a vacuum. Ionic wind is a well known phenomenon that is currently exploited in an ever increasing range of products and with ever improving efficiency. View, for example, the 8 patents of Krichtafovitch assigned to Kronos Air Technologies, which uses them to move up to 20,000 CFM at speeds up to 1500 FPS.

I've been looking for something like that for years! Hooray that someone finally did it.

I've been learning a lot more about corona lately, and the corona particles impinging on neutral air molecules makes a lot more sense now. I'm still not sure:

  • What happens when the corona is local. In other words, corona forms anywhere the electric field strength exceeds the breakdown of air, which is about 30 kV/cm. With certain geometries, the conductive corona forms only directly around the conductor, and, although it effectively increases the size of the conductor, the electric field strength around it is not high enough for the corona to expand any further. So the conductive region sticks around the conductor and there is no spark-over. So how is current transferred through the still-insulating air in between two conductors with local coronas? Or is there no more conduction than normal? The corona creates ions which stay separated as ions and then diffuse through the neutral air gap? I guess that's what happens...
  • What the high-voltage source "sees" when a corona has formed. Does it just appear as a resistance? Do the particles have momentum which appears as inductance?
 
  • #14
skeptic
26
0
There was an academic paper about lifters in a recent issue of the Journal of Electrostatics. No mystery, but I was a little surprised at some of the references. Academics should ignore 'internet crackpots'.
 
  • #15
pervect
Staff Emeritus
Science Advisor
Insights Author
10,165
1,326
I've seriously neglected this thread. Anyway, to clarify something (in case anyone is still listening) - to experimentially distinguish between the ion hypothesis and the induced dipole hypothesis that I mentioned, it would be necessary to do an experiment to see if the exhaust of the lifter actually contained *ions*. I'm not aware of anyone doing this, even the previous poster who built one.

This could be done by seeing if a gold-leaf electroscope was discharged by the exhuast, for instance.

If the exhaust did contain ions under normal room conditions, it would still be interesting to see if it still contained ions when care was taken to use very pure, dry air (no dust particles or water droplets) - I.e. it's possible that the exhaust might contain some ions normally, but that they aren't critical for generating lift.

For those posters needing a reference on the fact that there is no force on a dipole in a uniform electric field, but that there *is* a force on a dipole in a non-uniform electric field, I'll give the following reference:

http://www.physics.ucdavis.edu/Classes/Physics9HE/SH7(dipoles).pdf [Broken]

Force on a Dipole
In Figures 17 and 19, the forces responsible for the nonzero net torque act, of course, at different points.
Pairs of forces were equal and opposite—the net force was zero—because the field was assumed uniform, of
the same magnitude and direction at all points. In a nonuniform field, the forces might either be of different
magnitudes or different directions or both, and the net force would not be zero. The upshot is that a dipole in
a nonuniform field will in general experience a force as well as a torque.

On the topic of induced dipole moments,
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/diph2o.html

Even though the total charge on a molecule is zero, the nature of chemical bonds is such that the positive and negative charges do not completely overlap in most molecules. Such molecules are said to be polar because they possess a permanent dipole moment. A good example is the dipole moment of the water molecule. Molecules with mirror symmetry like oxygen, nitrogen, carbon dioxide, and carbon tetrachloride have no permanent dipole moments. Even if there is no permanent dipole moment, it is possible to induce a dipole moment by the application of an external electric field. This is called polarization and the magnitude of the dipole moment induced is a measure of the polarizability of the molecular species.

Air has a relative permittivity of 1.0006 according to google, so the effect is small.
 
Last edited by a moderator:
  • #16
Jonny_trigonometry
451
0
Omegatron said:
I've been looking for something like that for years! Hooray that someone finally did it.
I've been learning a lot more about corona lately, and the corona particles impinging on neutral air molecules makes a lot more sense now. I'm still not sure:
  • What happens when the corona is local. In other words, corona forms anywhere the electric field strength exceeds the breakdown of air, which is about 30 kV/cm. With certain geometries, the conductive corona forms only directly around the conductor, and, although it effectively increases the size of the conductor, the electric field strength around it is not high enough for the corona to expand any further. So the conductive region sticks around the conductor and there is no spark-over. So how is current transferred through the still-insulating air in between two conductors with local coronas? Or is there no more conduction than normal? The corona creates ions which stay separated as ions and then diffuse through the neutral air gap? I guess that's what happens...
  • What the high-voltage source "sees" when a corona has formed. Does it just appear as a resistance? Do the particles have momentum which appears as inductance?

For the first part, I think the electrons are pulled off the top wire (by the bottom plate), and repelled away from the wire with a force F=2kqa/r, where a=charge per unit length (because it's a line charge, although the equation is ideally an infinate line), and then attracted to the vertical lower plate by F=2k(pi)qb, where b=charge per unit area (because it's a charge on a plate, although the equation is ideally an infinate sheet). So the plate has a force pulling the electrons from the wire with less dependancy on the distance from the moving electron than the wire does. Another way to look at it is, when an electron is thrown from the wire in a near verticaly upward direction, it feels repultion from the line charge in a more localized area than the force from the plate, so it will get pulled around the wire and attracted to the plate, and get repelled from the wire at the same time, so it has a chance of zooming past the plate, or at least bumpung into some neutral air molecules and send them flying off in a downward direction and then get sucked into the plate. The main thing to consider is that the electric field around the whole apperatus is such that it shoots electrons out into the air, and then sucks them around to the bottom, and with so many electrons transferring thier momentum to air molecules in an assymetric way, there emerges a net force vector that pushes the apparatus through the air, or should I say, pushes the air through the apparatus.

I think I over complicated things, and Pervect explained the main thing I am trying to say, that "that there *is* a force on a dipole in a non-uniform electric field, I'll give the following reference:" - Pervect
 
Last edited:
  • #17
DaveC426913
Gold Member
21,067
4,440
Omegatron said:
That's a really awful attitude. Don't censor it; debunk it. Otherwise they'll never learn and keep coming back.
Haven't you ever been to a crackpot website? "Go to our website to find out what They don't want you to know!!!" Censoring them just makes them even more crazy.
The only thing that will accomplish is to alienate the rest of the folk. A forum devoted to rational and critical discourse will be diluted and polluted by crack pottery.

Doubly so on the Web: you can't change it - all you can do is protect your corner and ignore any intrusions.
 
  • #18
Intuitive
270
0
Ordinarily, Electrons would need a target with charge difference to seek an equalibrium and make all charge differences neutral.

But, If the emitter sends a charge potential of say +50keV to a (potential) target and the (Target) is switched off before the Electron charge reaches the other side, the Electrons should become mean free Electrons.

Lifters in a vacuum would have to utilize such or other techniques to convert the Electrons to mean free particles.

There are other probabilties like specific angle trajectories of the Electrons striking the (Aft) of the target rather than the (Bow) of the target allowing the Electrons to produce a Net (Push) with a mass of 1 per Electron against the rear of a target.:smile:
 
  • #19
pervect
Staff Emeritus
Science Advisor
Insights Author
10,165
1,326
If the "lifter" generates electrons, those electrons will also discharge an electroscope.

Hoever, it is rather unlikely that electrons cause the lift, because they have little mass. If electrons are generated, positive ions will also be generated. Having much more mass, they will have a much higher momentum for a given velocity, or for a given energy.

I've also attempted to explain why the generation of ions or electrons *may* not be necessary to generate lift.

[add]
I wouldn't rule out ions as the source of lift, by any means, but at this point I see two plausible (and purely electromagnetic) explanations for how the device could work, one of which involves ions, and one of which involves only dipoles.
 
Last edited:
  • #20
Don J
24
0
brookstimtimtim said:
Well, If this helps I built a lifter and a few test. I can say without a dout that is Ion Wind and no other forces. With that said I would like if a few people would like and read the info at a web site I made and give me a little review.
http://www.salug.org/~tbrooks/antigravity/AntiGravity.html [Broken]
glad than we can talk with a lifter user.
Here a variation based on Townsen T Brown original work
http://www.rimstar.org/sdprop/spinning/spinning.htm
You can even try under vaccuum
http://perso.wanadoo.fr/dorane/projet3.htm
http://perso.wanadoo.fr/dorane/projet2.htm
Hint use a tension variable 50 KV to 250 KV
4. OBSERVATION.
(a) Observe varying velocity with varying applied voltages (50 KV-250 KV dc)
(b) Observe varying effects of ion emission and corona discharge colorations at varying vacuum chamber pressures.
Copy of a letter from Thomas Thownsed Brown about tests made under vacuum chamber.
http://jlnlabs.imars.com/lifters/arl_fac/arlfac31.gif [Broken]
http://jlnlabs.imars.com/lifters/arl_fac/arlfac32.gif [Broken]
http://jlnlabs.imars.com/lifters/arl_fac/arlfac33.gif [Broken]

Edited to add
Biefield Brown effect experiment
http://perso.wanadoo.fr/dorane/effet_brown.htm

Other in english
http://www.rimstar.org/sdprop/bahnson/bahnson.htm

Index
http://www.rimstar.org/sdprop/index.htm
 
Last edited by a moderator:
  • #21
pervect
Staff Emeritus
Science Advisor
Insights Author
10,165
1,326
This would be a good topic for Mythbusters - various experiments have already been done to show that lifter's don't work in vacuum, but enthusiasts still make bizarre claims based on even more bizarre physics that they do.

See for instance Nasa's tests:

http://www.grc.nasa.gov/WWW/bpp/ComnErr.html#ELECTROSTATIC%20ANTIGRAVITY
 
  • #22
Don J
24
0
Quote from Nasa link

"None have been able to levitate their power supply, let alone an additional payload. This limits their utility when compared to alternative forms of aircraft propulsion."

That is true for communly assymetrical lifters tested which are replicas of the first model invented by Townsed T Brown in 1928

but.... later researchs and developments on disc shaped models

http://www.soteria.com/brown/pictures/bahnson6.jpg [Broken]

Have leaded to..
http://au.geocities.com/psyberplasmic/img/ccX-6-fig11.png [Broken]

http://au.geocities.com/psyberplasmic/ccX-6.html [Broken]
 
Last edited by a moderator:
  • #23
Omegatron
68
2
skeptic said:
Academics should ignore 'internet crackpots'.

I'm not an academic. :-)

Besides, proving crackpots wrong is a great way to solidy the correct ideas in your own mind. You'll find a suprising number of errors in your own internal models and refine yourself.

Plus, you can change their minds, and direct their endless enthusiasm towards something that might actually work.

pervect said:
to experimentially distinguish between the ion hypothesis and the induced dipole hypothesis that I mentioned, it would be necessary to do an experiment to see if the exhaust of the lifter actually contained *ions*. I'm not aware of anyone doing this, even the previous poster who built one.
This could be done by seeing if a gold-leaf electroscope was discharged by the exhuast, for instance.

The ions emitted would have to be both positive and negative, correct? You can't have a net flow of charge out of the device, or it would become charged itself. Can you emit negative and positive ions into the air without them immediately cancelling out? I guess I fundamentally don't understand how air ions (or charged dust particles) behave in neutral air. Do they immediately move towards an oppositely charged object and discharge? Do they just kind of aimlessly drift around but tend slowly towards an oppositely charged object? Would an atom with +2 charge hit a neutral atom and make them both +1? I don't know this stuff. (Where can I learn about it?) I was stuck on this stuff with another idea that depended on an object gaining charge in air, too. Then there's thermionic emission, too... :-)

Note that this is the same process claimed in Ionic Breeze machines and the like, so this stuff is not just limited to "internet crackpots", but also health practitioners who claim that the ions generated by these devices clean the air of bacteria and dust, etc. (They definitely do generate ozone, which, because it's toxic, kills bacteria, but also hurts the people who are breathing it.)

Jonny_trigonometry said:
For the first part, I think the electrons are pulled off the top wire *snip*

You think electrons are being removed from the wire and moving down to the plate by themselves? I thought the electrons were being stuck to atoms/molecules, which were then moving to the plate and discharging their extra electrons and becoming neutral again. Lone electrons can float through the air?
 
  • #24
michealsmith
124
0
dont think any1 knows
 
  • #25
ZapperZ
Staff Emeritus
Science Advisor
Education Advisor
Insights Author
35,995
4,711
Omegatron said:
I'm not an academic. :-)
Besides, proving crackpots wrong is a great way to solidy the correct ideas in your own mind. You'll find a suprising number of errors in your own internal models and refine yourself.
Plus, you can change their minds, and direct their endless enthusiasm towards something that might actually work.

Can you cite any cases where this has actually HAPPENED? In all my years on the 'net (since 1989), I have never come across a crackpot who actually have produced anything of worth, much less, being educated into the way why he/she has been wrong.

The ions emitted would have to be both positive and negative, correct? You can't have a net flow of charge out of the device, or it would become charged itself.

You must not have heard of "grounding". Besides, if you have a table-top "ion" source, then I have a particle accelerator to sell for cheap.

Then there's thermionic emission, too... :-)

But we know what that is. It's an electron source (not an ion source), and you'll KNOW when you have one since you'll need 900 C to get anything.

Note that this is the same process claimed in Ionic Breeze machines and the like, so this stuff is not just limited to "internet crackpots", but also health practitioners who claim that the ions generated by these devices clean the air of bacteria and dust, etc. (They definitely do generate ozone, which, because it's toxic, kills bacteria, but also hurts the people who are breathing it.)

You may want to double check on what is ionized and what isn't in such devices. Stripping electrons from gas molecules does not make it into an ion source.

Zz.
 
  • #26
Omegatron
68
2
ZapperZ said:
Can you cite any cases where this has actually HAPPENED? In all my years on the 'net (since 1989), I have never come across a crackpot who actually have produced anything of worth, much less, being educated into the way why he/she has been wrong.

Well... maybe not the "Leader Crackpots", but the "Gullible Followers" can certainly have their minds changed. You must not have tried?

You must not have heard of "grounding".

The lifters are assumed to be floating with respect to ground. Otherwise you'd have an additional source of thrust from the ions being emitted towards the ground and the charge returning through the ground wire.

But we know what that is. It's an electron source (not an ion source), and you'll KNOW when you have one since you'll need 900 C to get anything.

Metals emit electrons at any temperature above 0 K. The amount of electrons increases dramatically with higher temperatures, though, according to Richardson's Law.

You may want to double check on what is ionized and what isn't in such devices. Stripping electrons from gas molecules does not make it into an ion source.

So a gas molecule with a missing electrons is not an ion anymore?
 
  • #27
ZapperZ
Staff Emeritus
Science Advisor
Education Advisor
Insights Author
35,995
4,711
Omegatron said:
Well... maybe not the "Leader Crackpots", but the "Gullible Followers" can certainly have their minds changed. You must not have tried?

But have you? I asked for you to cite specific proofs that this has happened. All I said was that *I* personally have never encounter such a thing that you said. As far as I can tell, without a specific, even anecdotal evidence, that then becomes mere speculation.

The lifters are assumed to be floating with respect to ground. Otherwise you'd have an additional source of thrust from the ions being emitted towards the ground and the charge returning through the ground wire.

But that what makes it extremely unlikely. To be able to emit whole atoms (ionized or not) off a solid is not easy. And if these things are not grounded, then even emitting electrons (which is usually the easier of the two) would eventually stop due to charging effects.

Metals emit electrons at any temperature above 0 K. The amount of electrons increases dramatically with higher temperatures, though, according to Richardson's Law.

The Richardson model requires that the Fermi function broadening sufficiently due to an increase in temperature UNTIL the tail end of the function goes above the work function of the metal. What you just described is not thermionic emission based on the Richardson model. And if you're thinking of field emission, this will be even worse since you will have to supply an incredibly high fields on the metal's surface to get any appreciable tunneling currents, per the Fowler-Nordheim model.

So a gas molecule with a missing electrons is not an ion anymore?

An "ion" source typically is a self-contained source that supply such a thing. The ionic breeze that you quote isn't an ion source. It doesn't shoots ions out into the air. I use an ion gauge to measure UHV pressure in a vacuum chamber. It ionizes that gas molecules and attracts them to an anode, and the resulting current is proportional to the pressure. But no one calls one of these things as an "ion source". That would be absurd, and misleading.

Zz.
 
  • #28
Omegatron
68
2
ZapperZ said:
But have you? I asked for you to cite specific proofs that this has happened. All I said was that *I* personally have never encounter such a thing that you said. As far as I can tell, without a specific, even anecdotal evidence, that then becomes mere speculation.

Yes, I have seen people change their minds because of information on the internet.

But that what makes it extremely unlikely. To be able to emit whole atoms (ionized or not) off a solid is not easy.

Wait. Are you talking emitting metal ions? I think we're talking about different things.

And if these things are not grounded, then even emitting electrons (which is usually the easier of the two) would eventually stop due to charging effects.

Yes. That's what I just said.

The Richardson model requires that the Fermi function broadening sufficiently due to an increase in temperature UNTIL the tail end of the function goes above the work function of the metal. What you just described is not thermionic emission based on the Richardson model. And if you're thinking of field emission, this will be even worse since you will have to supply an incredibly high fields on the metal's surface to get any appreciable tunneling currents, per the Fowler-Nordheim model.

Ah. Is there anywhere online I can read more about these?

An "ion" source typically is a self-contained source that supply such a thing. The ionic breeze that you quote isn't an ion source. It doesn't shoots ions out into the air.

They claim that it does. I am asking if there is a way it could be emitting both positive and negative air ions into the room. My intuition would tell me that the air ions would immediately seek each other out and neutralize, but I don't have a solid understanding of the behavior of ions in a neutral fluid.

But no one calls one of these things as an "ion source". That would be absurd, and misleading.

Why would that be absurd? A device that creates ions is an ion source.
 
  • #29
ZapperZ
Staff Emeritus
Science Advisor
Education Advisor
Insights Author
35,995
4,711
Omegatron said:
Yes, I have seen people change their minds because of information on the internet.

And these are THE crackpots?

Wait. Are you talking emitting metal ions? I think we're talking about different things.

Read again. I said "solids". I didn't say "metals".

Ah. Is there anywhere online I can read more about these?
They claim that it does. I am asking if there is a way it could be emitting both positive and negative air ions into the room. My intuition would tell me that the air ions would immediately seek each other out and neutralize, but I don't have a solid understanding of the behavior of ions in a neutral fluid.

If there is an electric field that cause these ions and the liberated electrons to separate out, then you'd have a net current going to each electrodes. If not, no dice.

Why would that be absurd? A device that creates ions is an ion source.

Because it just isn't an ion source - it's an IONIZER. The ionic breeze doesn't actually pump out ions into the air. If it does, it's plastic casing will always zap people with static electricity, and the air on your body parts that you expose it to will stand up. Last time I sat near one of those, no such thing occured.

Zz.
 
  • #30
Omegatron
68
2
ZapperZ said:
And these are THE crackpots?

Define crackpot.

Read again. I said "solids". I didn't say "metals".

Wait. Are you talking about emitting solid ions? I think we're talking about different things.

I am asking if there is a way it could be emitting both positive and negative air ions into the room. My intuition would tell me that the air ions would immediately seek each other out and neutralize, but I don't have a solid understanding of the behavior of ions in a neutral fluid.

If there is an electric field that cause these ions and the liberated electrons to separate out, then you'd have a net current going to each electrodes. If not, no dice.

Let me try a different approach.

My internal model of the way a lifter or ionic breeze or ionic fan works is like this:

I have a metal wire and a flat metal surface, in air, with a high voltage source across them, with none of the circuitry connected to ground, and I raise the voltage enough to create a corona around the positively-charged wire, but not enough to create a corona around the less curved negative plate or a completely ionized path between them:

  1. Because of electron avalanches and stuff, air molecules next to the positive wire essentially give the positive wire electrons and become positive ions.
  2. The newly created positive ions will be repelled from the positive wire and attracted to the negative plate.
  3. Since they're gas molecules, I guess the ions bounce all over the place, but migrate relatively slowly (compared to their bouncing speed) from the positive to the negative electrode. I guess there's no reason why this behavior would be different in the corona region compared to the neutral, unipolar region. (Is there?)
  4. As they bounce off neutral air, but with a net flow in one direction, they impart momentum on the neutral air molecules that they hit. These now have a net flow in one direction, too, but aren't attracted to the plate, which is the only thing that causes lift in these devices.
  5. After traveling through neutral air, they reach the negative plate, where they take an electron (or two?) from the plate and become neutral again. After becoming neutral, they bounce around with no net drift in any one direction.

Is there anything wrong with the way I am imagining this? In this device, the ions would all be the same charge, and would only exist in between the two electrodes. None outside of that region.

So now, to explain what I mean by asking if oppositely charged ions can be emitted from such a device, here's a similar imaginary situation:

If I have two wires, in air, with a high voltage source across them, with none of the circuitry connected to ground, and I raise the voltage enough to create a corona around both wires, but not enough to create a completely ionized path between them:

  1. Air molecules next to the positive wire will give the positive wire electrons and become positive ions, and air molecules next to the negative wire will receive the negative wire electrons and become negative ions.
  2. The newly created positive ions will be repelled from the positive wire and attracted to the negative wire. And vice versa.

Now what happens? Do the negative and positive ions go directly to each other in the neutral region and neutralize? (Obviously in space they would, but maybe the neutral air prevents them from seeing each other or something?) Do they continue on to the oppositely charged electrode and neutralize? If you turned off the voltage, would they just kind of stick around in the air? Would they immediately seek each other out and neutralize or does the neutral air kind of keep them from meeting? Does a positive ion hitting a negative ion necessarily neutralize them, or can they stay the same charge sometimes? (With triboelectric effect, the opposite happens, I guess.) If they don't immediately seek each other out and neutralize, you could pulse the voltage source and keep a fan continuously blowing equal numbers of both charge ions out into the room.

Because it just isn't an ion source - it's an IONIZER.

So an "ion source" doesn't ionize anything?
 
  • #31
ZapperZ
Staff Emeritus
Science Advisor
Education Advisor
Insights Author
35,995
4,711
Omegatron said:
I have a metal wire and a flat metal surface, in air, with a high voltage source across them, with none of the circuitry connected to ground, and I raise the voltage enough to create a corona around the positively-charged wire, but not enough to create a corona around the less curved negative plate or a completely ionized path between them:
  1. Because of electron avalanches and stuff, air molecules next to the positive wire essentially give the positive wire electrons and become positive ions.
  2. The newly created positive ions will be repelled from the positive wire and attracted to the negative plate.
  3. Since they're gas molecules, I guess the ions bounce all over the place, but migrate relatively slowly (compared to their bouncing speed) from the positive to the negative electrode. I guess there's no reason why this behavior would be different in the corona region compared to the neutral, unipolar region. (Is there?)
  4. As they bounce off neutral air, but with a net flow in one direction, they impart momentum on the neutral air molecules that they hit. These now have a net flow in one direction, too, but aren't attracted to the plate, which is the only thing that causes lift in these devices.
  5. After traveling through neutral air, they reach the negative plate, where they take an electron (or two?) from the plate and become neutral again. After becoming neutral, they bounce around with no net drift in any one direction.
Is there anything wrong with the way I am imagining this?

Er.. have you ever tried putting a gas in between a high voltage? Unless you have a cathode (electron) source to ionize the gas beforehand, these gasses do not give up their electrons to the electrodes quietly. If they do, we won't have lightning. The so-called avalanche effects are from electrons emitted from the metals due to field emission. These electrons trigger a cascade effect that can cause other electron to be liberated from the metals due to secondary electron emission. None of these effects are due solely to the field alone.

Zz.
 
  • #32
Omegatron
68
2
ZapperZ said:
Er.. have you ever tried putting a gas in between a high voltage? Unless you have a cathode (electron) source to ionize the gas beforehand, these gasses do not give up their electrons to the electrodes quietly. If they do, we won't have lightning. The so-called avalanche effects are from electrons emitted from the metals due to field emission. These electrons trigger a cascade effect that can cause other electron to be liberated from the metals due to secondary electron emission. None of these effects are due solely to the field alone.
Zz.

As I said, "because of electron avalanches and stuff". The net result is that the air molecules give up their electrons, become ions, and fly away from the electrode.
 
  • #33
ZapperZ
Staff Emeritus
Science Advisor
Education Advisor
Insights Author
35,995
4,711
Omegatron said:
As I said, "because of electron avalanches and stuff". The net result is that the air molecules give up their electrons, become ions, and fly away from the electrode.

Yeah, but this is a known effect. Your fluorescent lights work this way. But creating a "lift"?

Zz.
 
  • #34
Omegatron
68
2
ZapperZ said:
Yeah, but this is a known effect. Your fluorescent lights work this way. But creating a "lift"?
Zz.

See step 4.

By lift I of course am referring to Lifters. Ionic breezes work on the same principle, but don't lift. I just mean that step 4 is the only cause of air flow. (As opposed to crackpot anti-gravity whatever for the Lifters.)
 
  • #35
ZapperZ
Staff Emeritus
Science Advisor
Education Advisor
Insights Author
35,995
4,711
Omegatron said:
See step 4.

By lift I of course am referring to Lifters. Ionic breezes work on the same principle, but don't lift. I just mean that step 4 is the only cause of air flow. (As opposed to crackpot anti-gravity whatever for the Lifters.)

Sorry, but you're assuming an ion bumping into a neutral particle does nothing to that neutral particle. Besides, how much of a "lift" do you think you'll get from nothing but a bunch of ionized gas molecules momentum transfer? Does your fluorescent light bulb buldges at it ends due to such a thing?

Zz.
 

Suggested for: How do ionic wind Lifters really work?

  • Last Post
2
Replies
41
Views
1K
  • Last Post
Replies
3
Views
257
Replies
33
Views
2K
Replies
6
Views
376
  • Last Post
2
Replies
41
Views
389
  • Last Post
Replies
3
Views
441
Replies
15
Views
263
  • Last Post
Replies
12
Views
318
  • Last Post
Replies
5
Views
567
  • Last Post
64
Replies
2K
Views
41K
Top