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You think you're thor now...
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I may have had a really cool idea at work today but like most of the gnarlier visuals I get this one is way over my head.
Heh, literally.

Picture rising hot air which has been made to tornado entering the base of a cylinder more than twice the diameter of said tornado on a curve so that this warmnado continues on a circular pattern around the inner surface in a helical pattern as it ascends.
Now picture the exact opposite happening from the top of the cylinder but with a descending coldnado.

Because both air flows are cohesive they should avoid intermingling too much when they meet and slip past one another, after a bit of a stabilization period, both streams of air should create a self regulating double helix.

Okay so just that is pretty neat as you could extract energy from running a Tesla turbine with hole patterns for each flow, but what it made me wonder is;
If the rising hot air is moist and the descending cold air is dry, then the boundary layer between the two should begin to condense some of that moisture out in the form of an elongated spiral of a cloud which should begin to mimic the weather and separate the two columns into opposite charges.

If the cylinder were long enough it might build up enough negative and positive charge at either end to spontaneously discharge then it should create a small scale lightning bolt snaking up the center.

No idea what to do with the lightning... home-made fulgurites maybe?

Planet Science http://www.planet-s...uses-lightning.aspx
What causes lightning? [2 fries shy of a happy meal, Oct 11 2019]

Lasers + electricity https://www.google....TBmEQ4dUDCAY&uact=5
Use a laser to initiate discharge [neutrinos_shadow, Oct 17 2019]


       Ooh. Not what I had in mind but very cool.   

       What I envision is falling cold air from an upper environment tornado-ing past rising hot air from a lower environment tornado-ing passively in a double helical swirl around one another.   

       If the length of the cylinder is long enough... it should act as an unregulated Van de Graff machine and make lightning when sufficient voltage is attained.   

       *I guess this one
pashute, Oct 10 2019

       Please explain [pashute].   

       OK, so you've got warm air spiralling upwards in the middle of the tube, and cooler air spiralling downwards in the outer part of the tube? And both lots of air are spinning in the same direction (eg, clockwise when viewed from above the tube)?   

       Interesting. I think the tube will have to be pretty wide, so that you have large enough masses of air in both of the flows, otherwise friction between them at the interface (between hot going up and cold going down) is going to rob them both of their movement.   

       But also, a question. The hot air is rising, and so presumably it escapes out of the top of the tube. The cold air is falling, and presumably escapes out of the bottom of the tube. Won't the system just tend to flip to a state where the hot air rises, and entrains cold air with it, so that you end up with only a single rising column of warmish air? What is it that drives the cold air downwards, against the friction it will have with the opposing rising hot air?   

       In other words, won't you just end up building a (possibly cyclonic) chimney?
MaxwellBuchanan, Oct 10 2019

       //OK, so you've got warm air spiralling upwards in the middle of the tube, and cooler air spiralling downwards in the outer part of the tube? And both lots of air are spinning in the same direction//   

       Same direction of spin yes but both columns of air spiral around one another along the outer part of the tube.
That they are also tornadoes themselves keeps the two from mixing.

       The friction of the boundary layer is what should begin to ionize the cloud formed at the interface... I think.   

       It's a double helix of airflow, with one single helical line being descending cold air and the other being ascending hot air, but the air doesn't directly follow each of those helical lines, instead each following another filled helical path that's curved along one of the lines of the main double helix. It's like if you took two flexible barber poles, one with red stripes and one with blue stripes, and twisted those two barber poles together. Right?
notexactly, Oct 10 2019

       Yep. One going up and one coming down with a fake cloud stretched in a coil of condensation between the two.
If the descending air is cold enough to cause ice crystals to form then the friction will cause a charge to build up. Lighter, positively charged particles should form at the top of the cloud while heavier, negatively charged particles should sink to the bottom of the cloud and when the charges grow large enough... SCRACK! Lightning.

       // Lighter, positively charged particles should form at the top of the cloud while heavier, negatively charged particles should sink to the bottom of the cloud //   

       Is that what happens in real thunderclouds? Why does it happen?
notexactly, Oct 11 2019

       Yes, from what I've read this is how lightning is formed.
I don't know why positively charged particles are lighter than negatively charged ones. I don't know how I even know how I already know this will work let alone why.

       It just popped into my head... and now... it's not just in 'my' head. See?   

       //heavier, negatively charged particles should sink to the bottom of the cloud // Uh, no. That's not how it works. There is charge separation (of course), but it's not because negatively charged particles are heavier. Suppose an ice crystal weighs 1mg, and it picks up ten negative charges. Its mass increases by 10^-26 grams, or one part in 100,000,000, 000,000,000,000,000.   

       It's more the case that larger particles, which tend to fall toward the bottom of the cloud, pick up negative charge as they fall - i.e. cause and effect are the opposite way around to what you thought.
MaxwellBuchanan, Oct 11 2019

       hmmm it's not what I thought... it's what I read and copied about lightning formation 'after' I had the thought.   

       From Planet Science [link]   

       "Lightning is an electric current. To make this electric current, first you need a cloud.   

       When the ground is hot, it heats the air above it. This warm air rises. As the air rises, water vapour cools and forms a cloud. When air continues to rise, the cloud gets bigger and bigger. In the tops of the clouds, temperature is below freezing and the water vapour turns into ice.   

       Now, the cloud becomes a thundercloud. Lots of small bits of ice bump into each other as they move around. All these collisions cause a build up of electrical charge.   

       Eventually, the whole cloud fills up with electrical charges. Lighter, positively charged particles form at the top of the cloud. Heavier, negatively charged particles sink to the bottom of the cloud.   

       When the positive and negative charges grow large enough, a giant spark - lightning - occurs between the two charges within the cloud. This is like a static electricity sparks you see, but much bigger."   

       //Lighter, positively charged particles form at the top of the cloud. Heavier, negatively charged particles sink to the bottom of the cloud.//   

       That's a little misleading. Lighter particles move to the top, acquiring a positive charge as they go. Heavier particles sink to the bottom, acquiring a negative charge as they go.   

       The "particles" are small (and even smaller) ice crystals - even the smallest is billions of times heavier than an electron. Even a single hydrogen atom is a couple of thousand times heavier than electron.
MaxwellBuchanan, Oct 11 2019

Would the same thing happen on a smaller scale given this double helical ascending/descending vortex scenario?

       If so then perhaps the two air streams could be ionized prior to entering the chamber so that the effect happens much more quickly.   

       ...and what to do with the lightning bolt? any chance of trapping it in a capacitor?   

       Lightning bolts are really pretty useless as a power source. A full-size, full- bodied strike is about a gigajoule (says the internet). So, that'll run a 1kW heater for 1,000,000 seconds or somewhere around 300 hours, if you could capture and use the energy. But you can't - because even if you could design a capacitor system that wouldn't be fried, the lightning will just bypass it. Lightning generally takes the easiest (in terms of action) route.   

       If you had a miniature spark generator, why would you wait for it to spark before you capture the energy? That's like having a gallon of petrol, throwing a match in it, and then thinking about capturing some of the energy.   

       No, letting the thing spark would be about the dumbest option. You would instead want to siphon off the charge separation and use that, rather than letting it go to waste in a spark.   

       However, in your case, it would be even more self-defeating because you're the one who's putting the energy into the system in the first place, to drive the airflow to cause the charge separation.   

       So, your scheme is analogous to this: (1) generate some electricity somehow (2) use that electricity to electrolyse water into hydrogen and oxygen (wasting some energy in the process) (3) wait until you've got lots of H2 and O2 (4) detonate the resulting mixture to make a very loud bang, flash and some heat then (5) set up some photovoltaics to capture a tiny amount of electricity from the flash - electricity that you can then use to... you get the idea.   

       Basic physics - you don't get nothing for nothing. Basic energy engineering: wind is free, sunshine is free, waterfalls are free; rotting vegatation is free; anything else you pay for.
MaxwellBuchanan, Oct 11 2019

       I'm not looking to make energy from nothing. I just figured out how to create lightning out of thin air and then found out that it just happens to be the way nature does it and I think it's totally cool. So there.   

       Lightning man!...   

       Besides if what you say is true then the whole contraption becomes one big battery if the charge is bled off before it discharges on its own.   

       If the heat source comes from lower compost piles, and the cold source comes from upper root cellars then the energy cost becomes stacking the bio-matter and cooling the two degree air a few more degrees.   

       Both columns of air can be made to respectively ascend, descend, and tornado passively. The lions-share of the actual work is done by mother nature herself so, although the potential energy to be extracted exactly equals or is less than the energy put into the system as a whole, the energy able to be extracted will be orders of magnitude greater than the share of the work I will need to do compared to the work mother nature will contribute.   

       //the whole contraption becomes one big battery if the charge is bled off before it discharges on its own// That was one of my points.   

       I have more than a sneaking suspicion that this won't work because the airflows won't behave the way you want them to, but you can prove me wrong with a photo of the working device.
MaxwellBuchanan, Oct 11 2019


       Oh alright... as soon as I find another place to settle with elevation changes, get all of my crap out of its sea-can, set up shop, renovate you-name-it to suit my wife's tastes, and stop crawling for a living,   

       ...you got it.
Until then it's just a really cool daydream.

       Consider though, if I am right, that tubes stretching from valley bottoms to mountain tops using natural convection currents could be used to generate enough electricity to power cities from thin air itself.
Complete control over environmental factors. No moving parts. Nothing to break down. No pollution. Simple elegant lightning at your disposal.

       ...and you should be able to extract some of the wind power as well since the whole interior isn't going to be sporadically Scracked by a lightning bolt.   

       Shame really. I liked that part. It had a whole muhahahahaha feel to it.   

       I like the concept but the thing is scale of environment, the whole kit and caboodle doesn't scale just because the amounts of materials are scaled. Something has to replace the expanse of the action's space. A charge or magnetic field placement, texture of container or a priming of participants in a certain way might be a solution.
wjt, Oct 12 2019

       //again???// I'm not saying it won't work. I'm just saying my gut feeling is that it won't work. If I'm wrong than that would be great.
MaxwellBuchanan, Oct 12 2019

       You are, and it will be totally awesome.   

       //Something has to replace the expanse of the action's space.//   

       I don't understand.   

       Are you saying that the heat and cold energy will dissipate because of making the chamber too tall?
Or are you saying that a larger expanse of air is needed to build up enough charge in the first place?

       ...or neither of those?   

       The natural process works with tiny bits in a very large space. Reduce the amount of tiny bits and drastically reduce the space, you have a different environment and possibly interactions. Some thing new has to be put in the model to equate the loss of vastness.   

       Just make it and modify it to workability as a new state.
wjt, Oct 12 2019

       Good luck with your Reynold's numbers.
MaxwellBuchanan, Oct 12 2019

       You got me. Still don't do math yet. I did find out how Reynolds numbers apply to tornadoes though.   

       "A prototype three-dimensional wind testing chamber capable of simulating tornadoes, named Model WindEEE Dome (MWD), was designed and built.Tornado-like vortices were simulated and investigated for swirl ratios ranging from 0.12 to 1.29. Flow visualization captured a laminar single-celled core at very low swirl ratios, a vortex breakdown bubble formation and then the drowned vortex jump at moderate swirl ratios, and a two-celled turbulent vortex at high swirl ratios. The surface static pressure of simulated tornadoes was measured and the mean velocity field of the tornado-like vortices was characterized using Particle Image Velocimetry method. It was shown that for radial Reynolds numbers greater than 6.7×104, the core radius and the swirl ratio corresponding the transition from laminar to turbulent are nearly independent of the radial Reynolds number. Local peaks in the axial profile of the tangential velocities near the surface, together with the very large surface pressure deficits, observed in the experimental data,are distinctive characteristics of tornado-like vortices and may be responsible for structural damages in tornadic winds."   

       Yes, now explain what any single sentence of that, other than the first one, means to you.
MaxwellBuchanan, Oct 13 2019

       Well, I can't be sure since it's the first time I've even heard of Reynolds numbers but I'd say they visualized various types and speeds of tornadoes using particles to determine when air goes from smooth to turbulent at its edges and found that wind speed and the size of the eye of a storm doesn't matter much when it comes to the break away point.   

       ...I think it means I need to learn more.
I wonder how spinning the twining tornadoes in the same direction as opposed to counter rotating them will affect the amount of charge built up? On one hand rotating them in the same direction will allow for less turbulent interface area, counter rotating them will cause more friction.


       Purely looking at a diagram from [bigsleep]'s reference. It seems the reverse is perfect. Plus a few particles that rub up the wrong way.
wjt, Oct 13 2019

       //from [bigsleep]'s reference. It seems the reverse is perfect. //   

       That might be right.
Bears experiment I figure.

       <wonders why such experimental data isn't already there for the searching>   

       Seems like something which should have been played with in the the 1920's or so... don't it?   

       Probably, most equipment is built for an exciting development. I would doubt the equipment gets radically played with to find that hidden secondary use. Isn't that is what undergrad assistants are for?
wjt, Oct 17 2019

       Here's a scary thought; If the system passively builds up enough of a charge to mimic actual lightning, then constantly bleeding off the absolute minimum to retard discharge would cause an instantaneous bolt if the power bleed-off were suddenly stopped.
Firing a spool of conductive filament from either end at a target seconds in advance of the discharge would give the bolt a path of least resistance and you could literally shoot lighting bolts.

Muhahahaha factor reestablished.

       Lasers. Lasers make everything cooler. See linky.
neutrinos_shadow, Oct 17 2019

       Nice! I did a bit of a search on ionized streams of air but it all seemed to be about using super heated gasses and I may as well use a bow and arrow if that's all the range I'd get... but Lasers?!... aw yeah.   

       Now were cookin with gas.
<raises one eyebrow and strokes cat while staring into the distance>


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