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Ionic Kinetic Energy Conversion Effect

[I-keesh'] ionic kinetic energy conversion effect
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Yes, I know it sounds like a sneeze, but I can explain it! Naturally, though, a bunch of preliminary background information is essential. Feel free to skip the parts you already know.

In the vacuum of space there is a dichotomy involving temperature. Almost everything is either very much too hot or very much too cold. However, for human beings wanting to live and work in space, there really is only one problem: too much heat.

Everything that people do involves energy being converted from one form to another, whether it be food burned in the cells of a body, or fuel cells converting hydrogen and oxygen into electricity and water. **ALL** such events involve the production of heat as a by-product, and this heat MUST be disposed of, for humans to successfully function in space.

Now at first glance one might think, "What's the big deal? Space is *cold*, isn't it?" But the answer to that is: Being surrounded by the vacuum of space is like being inside a Thermos bottle! Which, you probably know, retains heat really well!

A vacuum helps a hot object to stay hot because there are only three ways for a hot object to become cold, and two of them require a NON-vacuum in order to work. The first method is "conduction"; it requires that the hot object be physically contacting a colder solid object. But any spaceship, surrounded by the vacuum of space, obviously has no such colder solid object in contact with it, most of the time.

The next method, convection, requires that the hot object be in contact with either a liquid or a gas. AND convection generally requires something like a steady gravitational acceleration/force in which to work efficiently. NEITHER of which you will normally find in the vicinity of a working spaceship.

The third method for disposing of heat, radiation, is the only one that works effectively in a vacuum. Unfortunately, it is generally a low-efficiency process. LARGE radiators are required, to permit sufficient amounts of heat to convert from the form of molecular vibration into the form of escaping photons. You don't hear much about the radiator for the International Space Station, but it probably has a mass of several tons.

The ikece is a notion that might improve the efficiency of the situation. More efficient radiators are smaller and less massive -- and thus less expensive overall (it costs more than $10,000 a pound to send one into space, remember). Here is how prepare to find out whether or not the idea will work:

Let us construct a radiator of the following design: It has an aluminum core, with fins, not unlike what you can find inside any ordinary air conditioner unit. (But not exactly like it, either; the fins will probably be quite short.) Next, we add an "oxide coating". Now, ordinarily a hunk of aluminum almost always already HAS an oxide coating on it (microscopically thin; it is a layer of corrosion that is so tough it strongly inhibits further corrosion) -- but the natural oxide coating is too thin for the present device. We don't need a coating that's thicker than, say, a tenth of a millimeter, but we do need something thicker than the norm.

Now we take this radiator and bombard it with low-energy protons in a vacuum chamber. The protons penetrate and get stuck inside the oxide coating of the radiator. Since we are ONLY bombarding with protons, an overall static-electric charge builds up in the oxide coating.

When done, we may decide to add a little more oxide coating, just to make sure the protons are really sealed inside. Overall (describing ONLY the oxide material) we have created an electrostatic thingy known as an "electret".

Next, as part of a different but related task, we do some work with copper. We construct a copper tube, and line the inside the tube with thousands of sharp copper needles. We apply a strong negative static-electric charge to the tube, and then introduce fluorine gas to one end of the tube....

Ordinarily, a negative static-electric charge applied to a needle will leak off rather quickly, forming a "corona discharge", from which the electrons are carried away by air molecules. So inside the copper tube, before letting the fluorine in, the air in the tube is going to be absolutely saturated with loose electrons. And fluorine, being the chemical element with the greediest desire of all for electrons, will mostly take them from the saturated air, and form what we would have to call "freely floating floride ions". (Say that real fast 3 times, anyone?)

Some of the fluorine will chemically react with the copper, but that is OK, because after a copper fluoride layer builds up, that layer will protect against further chemical reaction between the fluorine and the copper. So additional fluorine gas molecules that flow through the tube will all become converted into freely floating fluoride ions.

The fluoride ions will emerge from the other end of the tube, where we direct them toward the radiator assembly. This procedure is done at full atmospheric pressure, perhaps even in an over-pressure chamber. Because the radiator has a fixed positive static-electric charge, the fluoride ions will be happy to go there. We want them to encounter so much air on the way, that when the ions arrive, they simply rest upon the outer surface of the radiator assembly. We definitely do not want them to embed themselves into the oxide layer! When done, the entire static-electric charge in the radiator's oxide coating will be completely neutralized by the fluoride ions resting on the surface of the coating. The radiator is now ready to go to space.

In space, while it is exposed to vacuum and shielded from sunshine, we pump hot liquid through the aluminum tubing in the radiator -- a quite ordinary thing. Heat is conducted to the fins of the radiator -- also an ordinary thing.

Now, the jouncing of atoms and molecules inside the fins of the radiator will probably not affect the buried protons very much, since they are bare atomic nuclei, after all. But the fluoride ions on the surface WILL be affected. Conduction of heat will inevitably arrive, and cause some energy to transfer to the ions.

This is a two-step process: FIRST, some oxide molecule jostles and bumps a fluoride ion and causes it to move a little away from the radiator; SECOND, the electrostatic attraction between the radiator and the ion will bring it back, where it will experience another bump. EVERY fluoride ion on the surface of the radiator will be doing this, constantly.

"So what?" you ask. I have been saving the juciest tidbit for last: Whenever an electrically charged particle is accelerated, it emits a photon! Ordinarily we design radio and TV antennas specifically to efficiently accelerate electrons, and thereby emit radio waves and mircowaves, for communication purposes. HERE we are merely helping the perfectly natural process of converting molecular kinetic energy into infrared radiation, via the intermediary of ionic kinetic energy.

THAT is the explanation of the title of this idea. Every time those fluoride ions bump, as described two paragraphs ago, they are experiencing accelerations! So they will emit photons, again and again and again...which is exactly what we want the radiator to do, efficiently. In theory, of course!

Vernon, Jul 19 2001

'Too much heat'? http://imagine.gsfc...nswers/980301b.html
1 [angel, Jul 19 2001, last modified Oct 21 2004]

(?) 'Too much heat'? http://www.sciencen...iginal/p00110d.html
2. Am I missing something? [angel, Jul 19 2001, last modified Oct 21 2004]

Apparently not. http://www.faqs.org...rt4/section-14.html
[angel, Jul 19 2001, last modified Oct 21 2004]

(?) Kids! Don't play with Oxygen Difuoride! http://www.usfa.fem...hazmat/page_376.pdf
[hippo, Jul 19 2001, last modified Oct 21 2004]

(?) ISS Cooling System http://spaceflight....ets/pdfs/td9702.pdf
If Vernon hasn't heard much about how the station is cooled it con only be because he didn't bother to look for info. The basics are in this manual (esp. Section 5). There are more detailed ones. [sirrobin, Jul 19 2001, last modified Oct 21 2004]

apply this. http://www.halfbake...n_20column_20widths
Shameless link to own idea. [lewisgirl, Jul 19 2001, last modified Oct 04 2004]

Electrets http://www.eclectic...k/mike/electret.htm
Explanation of electrets and how they are used in microphones [Vernon, Jul 19 2001, last modified Oct 21 2004]

Some Electret history http://www.bell-lab...1133/Heritage/Foil/
more info... [Vernon, Jul 19 2001, last modified Oct 21 2004]

Emissivity of materials http://www.electro-...ty/matlemisivty.htm
Some real world values for you to shoot at^H^H beyond, Vernon [neelandan, Mar 27 2002, last modified Oct 21 2004]

Bountiful power http://www.halfbake...idea/corpse_20power
you would win a nobel price. - bing, Mar 26 2002 [neelandan, May 30 2002, last modified Oct 04 2004]

Cargo Cult Science http://en.wikipedia.../Cargo_cult_science
"So we really ought to look into theories that don't work, and science that isn't science." - Richard Feynman. [neelandan, May 30 2002, last modified Nov 29 2014]

Manipulation of subsurface hydorgen atoms in palladium by scanning tunneling microscopy http://www.physorg.com/news8690.html
manipulated hydrogen atoms into stable sites beneath the surface of a palladium crystal [reensure, Dec 03 2005]

Endohedrals http://pubs.acs.org...8024fullerenes.html
Trapping stuff, including ions, inside fullerenes. [bungston, Dec 11 2005]

Science @ NASA: Staying Cool on the ISS http://science.nasa...2001/ast21mar_1.htm
To replace [sirrobin]'s busted link, a description of the honeycomb aluminum panels that function as the station's heat exchanger. [jutta, Feb 11 2007]

Crackpot Index http://math.ucr.edu.../baez/crackpot.html
Someone should apply this to Vernon's theories [neelandan, Feb 01 2011]

Some news about a moderately similar Idea http://news.stanfor...-mirror-112614.html
A special combination of physical characteristics are employed to enhance the efficiency at which radiant energy is produced. [Vernon, Nov 28 2014]


       Why would protons stick to a positively charged surface?

Also, if a particle has enough kinetic energy to move away from a surface would electrostatic attraction really bring it back?

Also, I'd guess that fluorine oxide is more stable than negatively charged ions (but see link).
hippo, Jul 19 2001

       hippo, the protons are not described as sticking to the surface; they are to be injected/buried/sealed/TRAPPED inside the surface coating!   

       "Also, if a particle has enough kinetic energy to move away from a surface would electrostatic attraction really bring it back?"   

       That question implies that I can use my bare arm to throw a ball into the air, and expect it to hit the Moon.... Since in actuality I can't, there is a problem with the assumptions behind your question. Probably forgetfullness about "escape velocity".   

       Fluorine/oxygen compounds are NOT desired here! Nor did I attempt to describe the creation of any such. NOR do I expect any to come about, if this idea is implemented.
Vernon, Jul 19 2001

       Vernon: If you're going to trap a charged particle inside the surface coating and expect electrons not to neutralise your charge then the surface coating must have infinite resistance.   

       Does Aluminium Oxide have infinite resistance?
st3f, Jul 19 2001

       see link.
lewisgirl, Jul 19 2001

       sirrobin, I didn't need to look up the specifics of the radiators on the ISS, because what I wrote is quite true: radiant cooling is very inefficient. Consider your car; let's assume it has a 200hp engine. Now at best only 30% of the heat-energy from the gasoline it burns is converted into the mechanical motion of your car. The rest (70%)is pure waste heat that must be disposed of through the car's radiator. How much heat is that? Well, 1 horsepower is 760 watts, so 70% of 200-times-760 is.... 106.4 kilowatts. I looked at those radiator specs for the ISS, and for it to dispose of only 75kw, it needs 6 radiators, each being more than 20 meters long. Compare THAT to the radiator in your car (which uses "forced convection")!!! ANYTHING that can improve efficiency of conversion of molecular kinetic energy into radiant energy will be highly desired in Space!   

       st3f, please study up on "electrets". They are static-electric devices roughly equivalent to permanent magnets, and they do exist. And one form of Aluminum Oxide is called "sapphire". It's a pretty good insulator, I hear...
Vernon, Jul 19 2001, last modified Aug 02 2001

       vernon: can you find me a decent electret link? All the ones I've looked at seem to either hang off nutty free energy sites or refer to a brand of microphone.
st3f, Jul 19 2001

       Thanks for the links. I wasn't impressed with the first one but the second was fine. As I'm seem to have a little momentum behind this let me continue to be devils advocate. In that spirit I've got four more things to question.   

       1) Having got over my initial surprise that electrets actually exist I'm going to start questioning how much charge they can carry. The only commercial application of them seems to be microphones. Since these are low power devices that would suggest to me that it may be difficult to get a large amount of charge on an electret. Since you're tryng to radiate large amounts of energy you will be wanting large amounts of charge on your radiator. Can you find any evidence that a large amount of charge can be carried by an electret?   

       2) I'll leave how you coat the radiator with ions up to you. Seeking clarification: Do you mean fluoride or fluorine? and why choose that chemical?   

       3) Electric interactions are very short range. When the ions get knocked off, what makes you sure that they will come back?   

       4) A radiator on a space craft would radiate low energy photons presumably peaking in the infra-red. What frequency will your radiator emit?
st3f, Jul 20 2001

       st3f, I'm sure that the amount of charge that an electret can carry is related to the size of the electret. The overall voltage isn't so important as the number of electric charges per unit of volume: obviously the more volume, the more charge. In this idea I wasn't so concerned about precise values as I was concerned about presenting something understandable. But do note I was describing a very large surface-area layer. If the unit of volume is based on the thinness of that layer, no single volume-unit need carry more than a few thousand volts (YOU can acquire rather more than that just by dragging your shoes across a rug on a cold dry day). If necessary, the manufacturing process can alternate between injecting protons (hmm, protons (hydrogen ions, that is) are SO small that they might be not be trappable; perhaps injecting lithium ions would be better) and applying the outer fluoride ions, one part of the radiator's survace at a time.   

       According to chemical nomenclature, "fluorine" is the correct name for a whole fluorine atom or molecule. Each fluorine atom has 9 protons in its nucleus, and 9 electrons in various orbits around it. "Fluoride" is the correct name for any fluorine atom that has acquired an extra electron, and has thereby become an ion. (If I recall right, to describe an element that has become an ion by LOSING electrons, the convention is to count them with Roman numerals: Fluorine-I would be the opposite of fluoride, for example, while fluorine-IX would be a bare nucleus.) Do note that fluorine and fluoride have rather different chemical properties (the first is deadly dangerous; the second is an essential trace-item in the diet, and good for the teeth in small amounts). The essay specifies using fluorine because it is the element that MOST strongly holds onto an extra electron, no special effort on our part required.   

       Actually, electric (and magnetic -- or more precisely: electromagnetic) interactions have the same infinite range as the gravitational force. They only APPEAR short-range, because of cancellation effects. Electric and magnetic phenomena are "bipolar"; we label the two polarities as Positive and Negative, or as North and South. Also, the electromagnetic force is ten million billion trillion trillion times stronger than gravity and this means... ----what! you don't believe that? OK, take an ordinary straight pin and set it on a table. Take a small magnet and slowly bring it down towards the pin. The pin will jump up to the magnet, right? Well, the entire mass of planet Earth was gravitationally pulling down on that pin!!! Gravity is FEEBLE...but gravity is (apparently) unipolar and thus cumulative, and so it dominates the Universe. Meanwhile, because the electromagnetic force is so strong, it is very difficult to separate large amounts of charge. And from a far-enough distance, even a well-separated pair of highly intense charges can be treated as if they have cancelled each other out, so from that distance, the two charges might as well not be separated at all.   

       Your question about whether or not the fluorides will return is relevant not so much because of being unlikely, as because the fluorides aren't going to be the only negatively charged particles in the space around the radiator. Note that if some number of fluorides DO escape, then the overall charge on the radiator goes up, which makes it more difficult for other fluorides to escape. But that same charge will attract whatever other negative charges happen to be in the vicinity of the radiator. Some of them might be fluorides that thereby have actually failed to escape, which is OK. Some of them might be other ions like chlorides or oxides, and that is OK, too. But most will probably be single electrons, and that is NOT OK. Electrons that settle to the surface of the radiator will not be significantly affected by the molecular jostling of the hot radiator. If we think of the fluorides as being a catalyst aiding the radiator's efficiency, then the electrons count as a catalyst-poison. They would make it easy for the fluorides to permanently escape. Perhaps some kind of final coating will be required, that allows the flourides to jostle and thereby radiate, while making sure that they can't really get away.   

       I expect the catalyzed radiator to radiate much like an ordinary radiator -- just at a greater rate.
Vernon, Jul 20 2001

       The Electrettes...didn't Phil Spector produce them?
thumbwax, Dec 28 2001

       AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2
AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2
AlO2 H+ AlO2 AlO2 AlO2 H+ AlO2 AlO2 AlO2 H+ AlO2 AlO2 AlO2 H+ AlO2
AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2 AlO2
AlO2 F- AlO2 AlO2 AlO2 F- AlO2 AlO2 AlO2 F- AlO2 AlO2 AlO2 F- AlO2

       Is this the sort of structure you were describing, Vernon?
neelandan, Mar 22 2002

       neelandan, yes, sort of. You're not giving the fluorides very much room for jostling, though. (And I mentioned in another annotation that perhaps lithium ions would be better than the hydrogens.)
Vernon, Mar 26 2002

       From what I understand it, boncing ion do not emit light. they just transfer the kinetic energy back where it come from. Photon are emitted from electrons move from a higher orbit to a lower orbit and lost its energy by creating the photon. Only during the discharging of ions that lights will come out. If you are coming at with a way to converting heat to radiation better than a black body can convert radiation to heat, you would win a nobel price.
bing, Mar 26 2002

       bing, apparently you missed the primary fact here: Whenever a charged particle experiences an acceleration, it emits a photon.   

       Look up "synchrotron radiation" sometime, as an extreme example of that phenomenon. So, since every bounce of every particle counts as it experiencing acceleration, what do you suppose would happn if the bouncing particles are charged?
Vernon, Mar 27 2002

       Ionically, It all depends on how much they're charged. They are bouncers, after all. And they know their math. I'd imagine that if they were overcharged they'd accelerate photons right through glass and into space and of course, shout "Come and get me, Coppers!"
thumbwax, Mar 27 2002

       I also missed that fact heated body emit radiation anyway (Infrared radiation for people reading this but don't understand). But you are the one thinking loose ions trap inside a static field makes a better radiator. Somehow ion lost most of its energy by radiation between the time it escape and then falling back to the charged plate. That is macroscopic equivalent of toss a static charged rubber ball into air and hoping the rubber ball will generate an EMP blast. (Note in both case, charge particles are under constant acceleration)   

       I guess some photon will come out when ions first escape and when they collapse back to the wall of charged field. Once again, most of energy are converted back into heat. I still do not see how this is more efficient heat dispenser unless you cool the free ions using superconductor that create a oscillating electric static field like the atom align and release cooling technique used to to cool near absolute zero. Anything less will create more heat than it dispenses.
bing, Mar 27 2002

       bing, you seem to be misinterpreting what I am thinking. "Somehow ion lost most of its energy by radiation between the time it escapes then then falling back to the charged plate" --that is NOT what I am talking about here!!!   

       I am hypothesizing that the process of experiencing a thermally induced collision will cause a charged particle to emit a photon. If heat arrives at an ordinary radiator in the ordinary way, and while flowing through that radiator heat causes all it the radiator's constituent molecules to bounce, well, ordinarily a few of them radiate infrared. Because ONLY a few molecules radiate, the ordinary radiator is inefficient at radiating.   

       Well, if it is indeed true that a charged particle emits a photon whenever it experiences an acceleration, then a chaged particle which gets collided-into by an ordinary thermally agitated molecule will, at the moment of collision, be experiencing an acceleration. It should radiate with every collison! I only wanted the ions to be free to move, to guarantee that they COULD experience acceleration during every collision with any ordinary thermally agitated molecule.   

       So, molecule bumps into ion, ion radiates and moves; then ion falls back and collides with molecule again (but probably some other molecule), and ion radiates again. That second collision may or may not send the ion careening again, but if it doesn't probably the next collision will.   

       And so I call these events the Ionic Kinetic Energy Conversion Effect (every collision with an ion converts some thermal kinetic energy into radiant energy, simply because every collision involves acceleration, and every charged particle supposedly emits a photon when in the midst of accelerating).
Vernon, Mar 28 2002

       Ok, are we agreeing that only during collisions that photon will emit? In oscillating electrical field, photon will also emit from ions or electrons if you get the frequency right (that is the principle of synchrotron radiation and laser) but that is not what you want your device to do.   

       In that case, ion collisions do not radiate more heat than neutral particle collision. And I don't think the frequency of collision will increase because you trap ions in an electrical field. Mostly due to the low density of ions because they repell each other so you can not fit too many of them in one place. Plus the free ions might even absorb radiation from space and bring more heat than it dispense.   

       Anyway, I wonder if anyone are studying cooling using superconductor that in my opion have a better chance of working.
bing, Mar 28 2002

       bing, every radio antenna works by using changing voltages to cause electrons in the antenna-wire to oscillate. Those electrically charged particles must experience acceleration in order to move in an oscillating manner. They obligingly emit photons at a frequency that depends on the rate of oscillation. There is no "getting the frequency right"! --because any frequency from ELF to microwaves can be produced.   

       One way of thinking about it is in terms of "what quantity of force did we apply to the charged particle, to make it oscillate? A large force is required to cause a rapid oscillation -- and higher-frequency emission is the result.   

       Similarly, when molecules collide and bounce, a reasonable amount of force is involved, and so if one of the molecules was charged, it should radiate a photon at SOME frequency. Maybe it won't be infra-red. But I am sure it will be better than nothing.   

       And yes, there is the possibility that ions would absorb incoming photons. Equilibrium phenomena always depend on where the higher concentration is. So far the evidence is that anything in shadow from the Sun experiences a lot of non-absorption, because incoming radiation from outside the solar system is rather feeble. We have to amplify most of what we detect, to extract any useful data from it. I think absorption will not be a significant problem with the proposed radiator.
Vernon, Mar 29 2002

       You don't want to increase ion collision using a oscillation field. You just convert more electrical energy into heat. You want the ions which come into the oscillation field to have less energy when they come out. In an induced oscillation field, you increase the heat in the system because electrical energy are added to the kinetic energy. The oscillation cooling method involve first excite them to a high natural frequency and then let them collapse into a lower natural frequency and release photon in that process. That is what I mean by the right frequency. Sort of the way laser works. Not so sure it will work on high energy free particles.
bing, Mar 29 2002

       bing, there is no need to bring any sort of oscillatory apparatus into this radiator description. The molecules and ions will "oscillate" just fine all by themselves, as a result of heat energy being transported into the radiator via plumbing: natural thermal motion, that is, You are introducing needless complexity and expense.   

       An IKECE radiator will either work as described, or I'll learn the reason why it won't work. And that is the rationale for posting the description here on the HalfBakery.
Vernon, Mar 29 2002

       And here I thought you are actually interested in discussion. Ok! the short reason it would not work is the free electrons inside any metal conductor will do a much better job converting random thermal motion to radiation if enough surface area are provided to allow the photon created by the electrons boncing inside of the metal matrix to escape into space than any ions you can possible find. As matter of fact, that is why radiator are designed the way they are.
bing, Mar 29 2002

       woo-hoo!!! I give this a croissant just for reminding me why I stopped attending MENSA get-togethers! (and because Vernon deserves a croissant for being able to understand all of this! croissant for bing too!)
runforrestrun, Mar 29 2002

       bing, I am certainly interested in discussion about why a particular idea will or won't work. It is just that the proper way to go about presenting a better idea is AFTER the original idea has been sunk (or at least had its shortcomings pointed out).   

       What you said about the unbound electrons in metal makes a fair amount of sense, but considering the vast numbers of electrons at the surface of an average radiator, and the associated poor radiative efficiency of same, it is difficult to see how that explanation can be completely correct. On Earth, of course, most radiators are designed to take advantage of convective flow, and any incidental photon emission is comparatively trivial. In Space, however, the design for radiators does not seem to match what you wrote. Consider those shiny curved radiators on the inside of the Space Shuttle cargo bay doors, for example. They COULD have been built with thousands of traditional small fins, to increase surface area, but they weren't. The implication is that either the designers didn't know what they were doing, or that something in what you wrote is erroneous.   

       So, if what you actually wrote is true, the ideal radiator for Space should be something like steel wool, only made with hollow fibers (for fluid flow), and of better radiative metal than steel (aluminum, perhaps).   

       P.S., what you wrote about superconductors is suspect in light of your last post, because most electrons are NOT unpaired, in a superconductor.
Vernon, Mar 29 2002

       My Dodge has a plastic radiator
thumbwax, Mar 30 2002

       Since I didn't design the shuttle radiator so I don't know why, but I am sure they have good reasons. You really just need large surface area to make a good radiator, fin or wool design would introduced the problem of photons emitted from one surface being absorbed back to another. Of course, you can mirror-polish the surface to reduce that, but it is usually not worth the effort.   

       I don't understand what you are trying to say about superconductors? I only mention superconductor because that is only way to create an oscilating electrical field without introducting heat into the system. Of course, if all electronic equipments use only superconductors, you wouldn't have the heating problems to begin with.
bing, Mar 30 2002

       The Space Shuttle door radiators are indeed mirror-polished, and considering the cost of shipping weight into orbit, anything that would allow less massive radiators should be very much worth the extra effort, such as mirror-polishing thousands of fins. So, since NASA generally does know what it's doing, I shall choose to think that the radiative efficiency of loose electrons at the surface of a metal is so low that using a fin design doesn't make enough difference to bother.   

       Another reason to say that concerns the nature of an electron: For all practical purposes, the very tiny mass of an electron is concentrated into a mathematical point (smaller than 10-to-the-minus-16 cm, ignoring quantum fuzzinessn -- which is actually a description of the location of that mathematical point, moreso than a description of the "body" of an electron). A thermal electron's collision-interaction could then be described as being rather "elastic" in nature -- which is an interaction that conserves energy (traslation: does not radiate much). An alternate way of looking at electron-electron collisions is that they very seldom have a "head-on" collision, because they are so small they usually miss each other. Sure, their electric fields can cause them to bounce, anyway, but the angles of their collisions are likely to be quite shallow most of the time. So not a lot of force enters the average thermal-electron collision, and so not a lot of energy gets radiated. See, when we MAKE electrons radiate, as by an imposed external oscillating electric field, it is the strength of that field that forces them to quickly about-face their motion, experience assicated accelerations, and emit photons. (And so energy from the external oscillator becomes converted into phtons, rather than the electron's own thermal energy.)   

       The ions I have suggested, however, are at least hundreds of thousands of times larger, are consequently much more inelastic, and also are much more likely to experience head-on collisions than electrons. Thus comparatively more significant amounts of force are involved, and equivalently more energy should be radiated in each thermal collision of an ion.   

       Chalk up what I wrote about superconductors to misinterpretaion/misremembering. Sorry.
Vernon, Mar 30 2002

       "In the South Seas there is a cargo cult of people. During the war they saw airplanes with lots of good materials, and they want the same thing to happen now. So they've arranged to make things like runways, to put fires along the sides of the runways, to make a wooden hut for a man to sit in, with two wooden pieces on his head for headphones and bars of bamboo sticking out like antennas--he's the controller--and they wait for the airplanes to land. They're doing everything right. The form is perfect. It looks exactly the way it looked before. But it doesn't work. No airplanes land. So I call these things cargo cult science, because they follow all the apparent precepts and forms of scientific investigation, but they're missing something essential, because the planes don't land." - Richard Feynman   

       From Table (link) Emissivity of:
EOI Mid-Temperature Black Coating (Up to 200 °C) 0.965 ± 0.005

       Assuming the value .96, the difference from a black body is .04/.96=4.17%. This is the figure of improvement for which Vernon would have us coat the surface with Aluminium Oxide (Al2O3 - I goofed back up there and nobody pointed that out!), fire low energy Hydrogen ions, or Lithium ions, as per a later annotation, and then expose to Flourine gas.   

       And then have the Holey Mass said over it. And take it on a procession on an elephant over the Holy city. And annoint with the ash from the Holey sheet of the Holy Cow. And smoke holy incenze in front of it. And have fifteen Hawaian witch doctors do things with dolls and pins and images of the eyekeesh all night. And all cargo cult science stuff (Link). And take it to Rome and have the Pope pee holy pee over it.   

       OK. Perhaps not all those things in that last paragraph. But I shall affirm that whatever procedure be used to prepare the surface, the improvement in emissivity is going to be less than 5% over the best conventionally prepared surface.   

       Is that a worthwhile improvement? You pays your money and you takes your choice.   

       Or, are you claiming to get the <fart sound> to be more emissive than a black body, Vernon?
neelandan, May 31 2002

       Cat shat on yer keys, Vernon?
neelandan, Jul 16 2002

       neelandan, I simply hadn't seen your recent annotations before today. And you did bring up an interesting point. As it happens, however, what you wrote depends upont the pre-computed properties of an "ideal black body", which is an object different from the thing described here. Do note that those black body computations have various built-in assumptions, such as that all the atoms at the surface of the black body are electrically neutral, and that they can only emit radiation if their electron shells are shaken enough by temperature.   

       The IKECE is described as an experiment to be performed, which starts with different assumptions. Why do you have a problem with that? Do you think that Official Assumptions are the only ones possible?
Vernon, Jul 17 2002

       "Black body radiation" is defined as the radiation inside a cavity with walls at a uniform temperature.   

       Anything producing radiation with the spectral characteristics of BBR is a black body.   

       </physics> <chemistry>   

       Aluminium Oxide + Flourine = Aluminium flouride + Oxygen
neelandan, Jul 27 2002

       In scientific terms, "ideal black body" = Naomi Campbell
thumbwax, Jul 27 2002

       Thanks, tw. I'll file that with the J-Lobum.
neelandan, Aug 05 2002

       neelandand, true, aluminum oxide plus FLUORINE does indeed yield aluminum fluroide plus oxygen. However, that is not what is described here! What do you get when aluminum oxide meets FLUORIDE? Nothing! Because each fluorine atom inside a fluoride ion already has the extra electron it would want to steal from the aluminum oxide.
Vernon, Aug 26 2003

       The solid described here is an ionic solid (like salt) but in which the two component ions are physically seperated and prevented from interacting by a third, nonionic stuff. I consideredsomething like this for my Ionic Balloon but I am still not sure it is possible. Is there any parallel for this? Can you seperate the sodium and chloride of salt with a wall between them?
bungston, Dec 01 2005

       [bungston], in an ordinary ionic solid the ions are very close together and the electrical attraction between them is very strong. Here I'm suggesting embedding positive charges (like protons or lithium ions) into a material like aluminum oxide. When the fluoride ions reach the suface of the oxide, there is a fair distance (intermediate atoms) that will separate the charges. The inverse-square-law then gives us rather less attractive force between the ions. If the embedded charges are fixed in place (which would be more true of lithium than of hydrogen/protons), then the lessened attraction should allow the fluorides to vibrate freely, bouncing up off the suface of the oxide and back again, rather than staying stuck/plastered-against the surface of the oxide. We NEED that bouncing for the IKECE to work.
Vernon, Dec 01 2005

       But in essence, this is lithium fluoride, the salt. The forces holding Li and F onto the substrate are the same ones that bind them in an ionic solid. One could substitute sodium instead of lithium and chlorine instead of fluorine in the IKECE, right? So the question: is there any parallel? The pull between the partners would still be super, super strong, and they are so small that i suspect physical barriers (here aluminum foil) will not be able to keep them from coming together.   

       Are there any ionic solids where the ions are physically held seperate from their charge partners?
bungston, Dec 01 2005

       [bungston], the ARRANGEMENT of ions in a salt crystal, versus what I'm describing here, is rather different. In a crystal each positively charged ion is pretty well surrounded by negative ions, and vice-versa. That makes it pretty difficult to separate them. So instead of that kind of 'top down' approach, I specified a 'bottom up' approach, by creating ions from neutral atoms, and then controlling where they end up. There is a vague similarity between a capacitor and what I've described here. That is, if the positive ions are are embedded all to about the same depth in the aluminum oxide, then they count as a layer, like a layer of foil in a capacitor. The thickness of aluminum oxide through which they passed, before stopping, becomes the insulator-layer, and the freely-floating negative fluoride ions, also generated from initially neutral atoms, are statically attracted to the top of the aluminum oxide, are too big and arrive too slowly to become embedded, and count as a third layer in this "capacitor" description.
Vernon, Dec 02 2005

       I have been thinking about my question regarding ionic solids where the ionic partners are physically seperate. I believe something of the sort has been made using buckyballs - the carbon cage can hold one of the ionic partners. If these compounds already exist, they might be used as an "off the shelf" answer to see if they are more efficient radiators of heat.
bungston, Dec 03 2005

       Something like this was recently reported, but in a palladium crystal. For an explanation of how it was done, and a description of the surface effects which bode well for future development of catalysts, see link.
reensure, Dec 03 2005

       / Whenever an electrically charged particle is accelerated, it emits a photon! /   

       I am thinking about table salt again. I do not think that the charge of the particle (positive or negative) matters as regards photon emission - so even though /In a crystal each positively charged ion is pretty well surrounded by negative ions, and vice-versa/, the thermal movement of both the sodium and the chloride should produce abundant photons. I am not sure why physically seperating the charged particles would make this work better.
bungston, Dec 12 2005

       [bungston] you are neglecting the fact that the process is reversible. Photons being emitted by one ion can be absorbed by any neighboring ion. I venture to guess that at the surface of a salt crystal, ions are so close that most photons emitted are absorbed by neighors.   

       In the IKECE, though, those freely floating fluoride ions are WELL separated, comparatively. Less likely for emissions to be captured by neighbors, therefore.
Vernon, Dec 12 2005

       If it is charged particles that do the radiating, I wonder if simply adding a static charge to a metallic body would make it radiate better? More electrons to jostle.   

       It seems like it would be simple to test but perhaps not; judging by [neelandens] link up there emissivity is actually a measure of reflectivity. All of the different emissivities listed actually seem to just be increments of reflectivity, and related to the surface treatment of the radiator (paint, rust, polish etc).
bungston, Dec 12 2005

       [bungston], yup, this Idea was posted to see what would happen if it was tested.
Vernon, Dec 13 2005

       Then test it, my man, and tell us instead of yapping inanities at us!
neelandan, Dec 13 2005

       Now, now, [n], you know that this is the theoretical half of things. Strictly armchair. We do not want to be requiring real world testing. That would raise the bar too high.
bungston, Dec 13 2005

       [neelandan], if I had the $$ and the time, I wouldn't mind a bit, doing the testing of this and plenty other wild ideas.
Vernon, Dec 13 2005

       For those just joining us - The IKECE hypothesis: extra available charged particles in a body improves the ability of the body to radiate heat. I think this is reasonable and apparently quite novel.   

       I have thought of a way to test this. Two petri dishes of mercury under a vacuum bell. The dishes stand on a few grains of sand or cork, to minimize conductive losses thru the bottom of the dish. Because it is vacuum there will not be convective losses to air. Becuase it is mercury it will not vaporize. Mercury is liquid, so the surface characteristics of the two dishes will be the same. Mercury makes a mirror-smooth reflective surface, comparable, I am sure, to the best radiators in the linked list.   

       Both dishes are heated equally, and the rate of cooling monitored. The only way for the mercury to cool is by radiating away the heat.   

       Unfortunately it does not seem that you can make an ionic solution in mercury. Mercury can carry a current, which I believe will provide electrons, but this will also heat the mercury because of electrical resistance. Would imparting a charge to one dish allow it to carry extra electrons? If so, and if [Vernon's] hypothesis is correct, the extra electrons should make the charged dish cool faster than the uncharged one.   

       Amore analogous test to the IKECE scheme would be to test emissivity of some liquid in which you could dissolve a salt. Unfortunately, water evaporates (especially in vacuum) and thus it would not be a pure test of emissivity, especially since I suspect that salt solutions would alter vapor pressure. I could not think of a liquid which would dissolve a salt, yet not evaporate under a vacuum.
bungston, Jan 04 2006

       [bungston], mercury DOES vaporize to some extent in a vacuum. And heating it can cause more to vaporize. AND it's toxic. I recommend using gallium (element #31) instead of mercury.   

       Next, regarding electric charge, remember that two sorts of charge are possible. You can positively-charge the liquid metal by removing some electrons. The hypothesis should not care about which type of electric charge is experiencing acceleration, as a photon-emitter
Vernon, Jan 05 2006

       I have a better idea on how to cheaply test the IKECE hypothesis. Ethylene glycol is widely available (antifreeze) and has a low enough vapor pressure. It will still vaporize under a vacuum, but probably not so much as to greatly confound the cooling rate as measured over an hour or 2.   

       Ethylene glycol is polar and will dissolve salts. IKECE deals with charged ions, not electrons, and so while a test using electrons (as above with mercury and gallium) might work, I think dissolved salts will be better.   

       So: 2 insulated open dishes of ethylene glycol, one with dissolved NaCl and one dissolved sugar (a nonionic solute), cooling side by side in a vacuum bell. If the IKECE hypothesis is true, the salt containing dish should cool faster because of the presence of ions at the surface.   

       This is now squarely in the realm of a high school or college science project.
bungston, Feb 03 2006

       Interesting! Thanks! Although somthing more than just an evacuated bell jar may be needed. You DO want to approximate the conditions in Space where star's radiant energy in a shadow (block out Sun) is pretty diffuse. On Earth EVERYTHING is radiating a bit in the infrared. The bowls of solvent, even in the bell jars, would be receiving radiation from their surroundings.
Vernon, Feb 06 2006

       Yes, Vernon, it is the "invisible dragon in my garage" all over again.
neelandan, Feb 09 2006

       It seems to me that this idea would work best with a smooth surface, without fins.   

       Why? If there are fins, there are "valleys" between them.   

       The radiation emitted by the fluoride ions that have thermally jumped away from the radiator, and which are now being electrostaticly accelerated back to the radiator, will probably uselessly strike a radiator fin, if the fluoride ion came from between the fins.   

       So if the radiator is a sphere, each photon emitted by a fluoride ion has a much better chance of "missing" the radiator, and not being re-absorbed.   

       PS: I do think that this idea might work. However, a simpler (if perhaps less accurate) description of why it would work might be as follows:   

       The cold fluoride ions stick to the radiator electrostatically, the hot fluoride ions form a gaseous halo around the radiator. (Isn't a cloud of ions a plasma?)   

       When the cold ions are heated (by conduction, from the solid part of the radiator), the become part of the halo.   

       Each hot fluoride ion in the halo effectively has an infinite surface to mass ratio, which makes them good at radiating heat.   

       Whenever a hot ion emits a photon, it becomes cold, and gets sucked back to the radiator by electrostatic attraction.   

       Whenever a hot ion gets hit by an *extra* photon (which doesn't happen too often, since each ion is very small), it gets hotter, which causes it to move further away from the radiator, which gives better a chance to give up it's heat.
goldbb, Oct 01 2009

       If the chloride atoms become a plasma once they're heated, does that mean that before they're heated, they're a proto-plasma?   

       (sorry, couldn't help myself)
goldbb, Oct 04 2009

       [goldbb], Since it is not the material of the fins that are doing the radiating, they should reflect emitted radiation. The appropriate absorber would be another fluoride ion. But will the "cloud" of ions at the surface of the radiator be dense enough to ensure reabsorption is common? Obviously we should avoid that!
Vernon, Oct 05 2009

       //Mercury makes a mirror-smooth reflective surface, comparable, I am sure, to the best radiators in the linked list// Mirror-smooth reflective metal surfaces are amongst the worst possible radiators! That's why a thermos flask has a shiny metallic coating on the glass surfaces adjacent to the vacuum.   

       For any substance, or object, the emissivity for a given wavelength lies between 0 and 1. You just can't get around that, with any method, however complex, without breaking the laws of thermodynamics. And as [neelandan] says, materials exist with emissivities close to 1 in the range of thermal infrared, so there is very little room for improvement.
spidermother, Jan 31 2011

       [spidermother], perhaps you can explain why the heat radiators inside the Space Shuttle payload bay doors are highly reflective?
Vernon, Jan 31 2011

       Crackpot alert! <link>
neelandan, Feb 01 2011

       A bit of a google suggests that the shiny surfaces you see are the insulating louvers that cover the underlying radiators. When heat is being rejected, they swing open. In their closed position they prevent unwanted heat loss, or unwanted heat gain from sunlight, depending on requirements.
spidermother, Feb 01 2011

       [spidermother], thanks. Now tell me where in the main text have I specified that highly reflective surfaces must be used?
Vernon, Feb 01 2011

       I was referring to [bungston]'s annotation about shiny mercury (which I thought you should have challenged), and your annotations about shiny space shuttle radiators.
spidermother, Feb 01 2011

       //A special combination of physical characteristics are employed to enhance the efficiency at which radiant energy is produced.//   

       My understanding of that article is that a special combination of physical characteristics [is] employed to create a custom emissivity spectrum; it has a very low emissivity (and high reflectivity) for the wavelengths that comprise sunlight, but a very high emissivity (and therefore low reflectivity) for some band of longer wavelengths.   

       Ordinary white paint has similar (but possibly somewhat inferior) properties.
spidermother, Nov 28 2014

       Regarding sealing the hydrogen/lithium ions in: Usually when you color a piece of aluminium by type 2 anodization, you first anodize it (which deepens the oxide layer and makes it porous), then you soak the colorant in, and finally you seal the top of it by heating… or… something—it's been a while since I've read up on it. Anyway, that seems like it could be adapted for this application.   

       Now that we have graphene in research quantities, and can expect it will be available soon in industrial quantities, I wonder if it might be a good material to separate the positive and negative ions. Obviously it couldn't be used on its own, because it's electrically conductive. It could be used for thermal conduction, too—I seem to recall it's good at that.
notexactly, Mar 29 2015


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