Ion drive for aircraft imminent.

The commonly used name for these EHD devices made by amateurs is "lifters". The problem with their not being able to fly independently is the power supplies are so heavy. Look for example at the lifter here:

How to: "Lifter" Power Supply.

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Quite commonly the lifters weigh, and the thrust they can produce, is in the range of grams but the power supplies weigh in the range of kilograms. So how do you solve that problem?

Let me give an analogy. Many people are aware of the technical innovations the Wright brothers made to be able to develop a successful flying machine. They made their own wind tunnel. They tested various air foils to find efficient ones of high lift. They developed a warping wing technique for steering.

However, not as well known is the one key innovation they made for which all those other innovations would have been worthless. When many scientists of the time after doing a mathematical analysis asserted that no heavier-than air flying machine could work, oddly enough they were *right*. But the problem was, they were basing this on the power sources widely known at the time, steam engines. But the steam engines were so inefficient they could not supply sufficient power for their weight. They were too heavy.

Around the time of the Wright brothers though the internal combustion gasoline engine was coming into use for automobiles, but they were still too heavy for the Wright brothers use. So the one *key* innovation the Wright brothers made was that they designed and built their OWN lightweight internal combustion engine.

Now, back to the EHD propulsion method. The power supplies are too heavy, so what can we do about that? Well, you can make them out of lightweight materials. That's a possible route to follow, but most amateur and even professional experimenters have used ready made power supplies or used ready made parts to build them. The result is they are all pretty standard weight for the power they put out.

But let's analyze this further, *why* are the power supplies so heavy? It turns out the reason they are so heavy is the voltage needed for the ion propulsion method is in the range of tens of thousands of volts, frequently as high as 50,000 volts. This then requires heavy transformers to produce voltage this high. Alright then, can we find a way to reduce the required voltage?

Yes! It turns out if you reduce the diameter of the wires doing the ionization of the air then the required voltage is reduced. In fact, according to the math if the wires are at the nanoscale then the required voltage might be reduced to only tens of volts instead of tens of thousands of volts. For the small-scale lifters, if you used now wires at the nanoscale, it may be they could be powered by a couple of 9-volt batteries connected in series.

So that's the key point, for nanowires the voltage required for ionization is severely reduced. This is the content of Peek's Law:

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Bob Clark

---------------------------------------------------------------------------------------------------------------------------------- Finally, nanotechnology can now fulfill its potential to revolutionize

21st-century technology, from the space elevator, to private, orbital launchers, to 'flying cars'. This crowdfunding campaign is to prove it:

Nanotech: from air to space. https://www.>>> Nanotechnology makes possible an "ion drive" for air vehicles analogous

No. And under even ideal conditions, they don't work for long.

Why do people invent (and press release) crazy sci-fi dreams that ignore basic physics? There is a reason why helicopters have gas turbine engines and giant fan blades... and horrendous fuel consumption rates. Why don't they just use their jet engines to lift the vehicle?

--
John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement 
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Robert Clark
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Yes, that's a good example. Electric, battery-powered airplanes and helicopters already exist. However, the key point is according to the mathematics you can get even better power-to-thrust ratio with ionic propulsion using ionizing wires at the nanoscale than helicopters achieve.

Bob Clark

---------------------------------------------------------------------------------------------------------------------------------- Finally, nanotechnology can now fulfill its potential to revolutionize

21st-century technology, from the space elevator, to private, orbital launchers, to 'flying cars'. This crowdfunding campaign is to prove it:

Nanotech: from air to space. https://www.> ...

Oh I dunno, I thought this 18-rotor electric copter-thingie was kind of cute.

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Michael

Reply to
Robert Clark

As mentioned previously, battery-powered airplanes and helicopters do exist. The ionic propulsion will likewise be battery-powered but at a more efficient power usage, if the ionizing wires are at the nanoscale.

The greater efficiency for ionic propulsion with nanoscale wires can be confirmed with any wires at the nanoscale, not just carbon nanotubes. For example, the intense fields created by nanoscale wires in microcircuitry boards is well-known to those in the field. So anyone who has familiarity working with microcircuitry boards with nanoscale wiring could confirm this.

And that's all that's required. That in itself would be the game changer. Even if it's only done on a model the size of a model airplane, once it's shown that nanoscale wiring for ionic propulsion produced better power-to-thrust ratio than helicopters, that would be sufficient for this to supplant helicopters as a hovering transport method.

Bob Clark

---------------------------------------------------------------------------------------------------------------------------------- Finally, nanotechnology can now fulfill its potential to revolutionize

21st-century technology, from the space elevator, to private, orbital launchers, to 'flying cars'. This crowdfunding campaign is to prove it:

Nanotech: from air to space.

formatting link

"Robert Clark" wrote in news:nvab5b$is1$ snipped-for-privacy@dont-email.me:

The reason we don't have flying cars has nothing to do with the method of propulsion. We've *had* flying cars for decades. And this will do nothing to make them a) cheaper, b) easier to fly, or c) safer when there are tens of millions of them in the air at once.

Just like all propeller and rotor drive craft became obsolete when jet engeins were invented. Sure.

Effectively, jet powered cars? Because it sounds like there will be a high speed exhaust of _some_ kind behind the vehicle. Which makes it . . . unlikely.

Plus, two orders of magnitude increase in thrust to weight from current ion engines isn't even close to what a car needs.

The electricity has to come from _somewhere_.

As is usual, nearly universal, with all announcement of revolutionary new technologies, this reads more like a prospectus for investors than anything else. Which is to say, he wants to invest a whole lof of other people's money into finding out if it works.

If he really believed it would work, he'd invest his own money, and keep _all_ the profits himself.

--
Terry Austin
Reply to
Robert Clark

Get back to us when Honda is selling flying cars.

And note that top-posting is an email thing, discouraged on usenet.

--
John Larkin         Highland Technology, Inc 

lunatic fringe electronics
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John Larkin

And it won't hover for long before it's out of fuel. There's a good reason for that.

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John Larkin         Highland Technology, Inc 

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John Larkin

High-voltage power supplies don't need heavy transformers. But they do need a source of power. I doubt that an ion thruster could lift its own batteries for five minutes even if the power converter weighs zero.

Again, you won't get enough lift to support those two batteries, and they would be dead in minutes anyhow.

The tiny tips would erode rapidly, too.

Don't top post on usenet.

--
John Larkin         Highland Technology, Inc 

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Reply to
John Larkin

What voltage do you need to guarantee specified operation in humid and rainy environments?

Michael

Reply to
mrdarrett

On 11/3/2016 10:41 AM, John Larkin wrote:

wiki (note the last line) Ion thrusters are categorized by how they accelerate the ions, using either electrostatic or electromagnetic force. Electrostatic thrusters use the Coulomb force and accelerate the ions in the direction of the electric field. Electromagnetic thrusters use the Lorentz force. In either case, when an ion passes through an electrostatic grid engine, the potential difference of the electric field converts to the ion's kinetic energy.

Ion thrusters have an input power spanning 1?7 kW, exhaust velocity

20?50 km/s, thrust 25?250 millinewtons and efficiency 65?80%.[1][2]

The Deep Space 1 spacecraft, powered by an ion thruster, changed velocity by 4300 m/s while consuming less than 74 kilograms of xenon. The Dawn spacecraft broke the record, reaching 10,000 m/s.[1][2]

Applications include control of the orientation and position of orbiting satellites (some satellites have dozens of low-power ion thrusters) and use as a main propulsion engine for low-mass robotic space vehicles (for example Deep Space 1 and Dawn).[1][2]

The ion thruster is not the most promising type of electrically powered spacecraft propulsion (although the most successful in practice).[2] An ion drive would require two days to accelerate a car to highway speed. The technical characteristics, especially thrust, are considerably inferior to the prototypes described in literature,[1][2] technical capabilities are limited by the space charge created by ions. This limits the thrust density (force per cross-sectional area of the engine).[2] Ion thrusters create small thrust levels (the thrust of Deep Space 1 is approximately equal to the weight of one sheet of paper[2]) compared to conventional chemical rockets, but achieve high specific impulse, or propellant mass efficiency, by accelerating the exhaust to high speed. The power imparted to the exhaust increases with the square of exhaust velocity while thrust increase is linear. Conversely, chemical rockets provide high thrust, but are limited in total impulse by the small amount of energy that can be stored chemically in the propellants.[3] Given the practical weight of suitable power sources, the acceleration from an ion thruster is frequently less than one thousandth of standard gravity. However, since they operate as electric (or electrostatic) motors, they convert a greater fraction of input power into kinetic exhaust power. Chemical rockets operate as heat engines, and Carnot's theorem limits the exhaust velocity.

Ion thrust engines are practical only in the vacuum of space and cannot take vehicles through the atmosphere because ion engines do not work in the presence of ions outside the engine. Spacecraft rely on conventional chemical rockets to initially reach orbit.

Reply to
Yuri Kreaton

But VTOL is a potential game changer in the event of hostile action. An aircraft that doesn't require a runway to take off or land has a natural advantage. They are impressively noisy when hovering though.

Also the vectored thrust made them very effective in dog fights.

Shame we (UK) don't have any left in service or even an aircraft carrier to put them on.

As for the ion drive - I can't see it ever being used other than in interplanetary space where atmospheric friction isn't an issue.

--
Regards, 
Martin Brown
Reply to
Martin Brown

As research toys; there are not as yet any electric airplanes or helicopters that could be called practical in any sense of the word.

An intense field does not automatically means motive power.

Are you saying microcircuitry boards have to be lashed down to keep them from flying away?

Yeah, sure.

You do know the tips of such ion generators burn away and the smaller the tip the faster they burn?

--
Jim Pennino
Reply to
jimp

Being near an ion drive would literally be a hair raising experience and likely to generate RFI far in excess of FCC standards.

--
Jim Pennino
Reply to
jimp

Wow, that's pretty good! Much better than two months! :D

Michael

Reply to
mrdarrett

The total power required is fixed by physics which means nanoscale wires in the power supply will melt due to I^2*R losses unless they are also superconductors.

--
Jim Pennino
Reply to
jimp

As toys and research projects, but not as practical machines.

--
Jim Pennino
Reply to
jimp

and afaiu when they stopped letting only the very best pilots fly them they tended to crash ...

Reply to
Lasse Langwadt Christensen

Sure, why not toss in some liquid nitrogen cooling while we're at it. :)

A bicycle is looking better and better. Maybe even a wingsuit.

Michael

Reply to
mrdarrett

"Robert Clark" wrote in news:nvfhtn$stq$ snipped-for-privacy@dont-email.me:

None of that adds up to flying cars. Again, the reason we don't have flying cars has nothing to do with propulsion systems. We've

*had* flying cars for nearly a century.
--
Terry Austin 

Vacation photos from Iceland:  
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Gutless Umbrella Carrying Sissy

...

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Reply to
Robert Clark

Unfortunately I just realized the default version of this script does not include your signature file. So I'll have to customize it. More work.

Bob Clark

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Robert Clark

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Wonder how it works in the rain...

Reply to
Ingvald44

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