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Polywell and Ionocraft

Posted: Mon Apr 20, 2009 2:44 pm
by Professor Science
SO! I was reading about reactionless thrusters filling time the other day when i stumbled upon something that didn't make physics cry, Lifters. Also comonly known as Ionocraft.

http://en.wikipedia.org/wiki/Ionocraft

The general gist is Ions are formed from the air and accelerated down at high velocity, as far as thrust to weight ratios most designs only accommodate an extra gram/watt more than their own weight. So I was curious about polywell as power source. at 100 mw that's 10E8 watts, or 10E8 grams, 10E5 kilograms or 50 metric tons. Does the current theorized WB 100 weigh more than 50 metric tons?

Re: Polywell and Ionocraft

Posted: Mon Apr 20, 2009 5:43 pm
by MSimon
Professor Science wrote:SO! I was reading about reactionless thrusters filling time the other day when i stumbled upon something that didn't make physics cry, Lifters. Also comonly known as Ionocraft.

http://en.wikipedia.org/wiki/Ionocraft

The general gist is Ions are formed from the air and accelerated down at high velocity, as far as thrust to weight ratios most designs only accommodate an extra gram/watt more than their own weight. So I was curious about polywell as power source. at 100 mw that's 10E8 watts, or 10E8 grams, 10E5 kilograms or 50 metric tons. Does the current theorized WB 100 weigh more than 50 metric tons?
That is in the ball park.

Posted: Mon Apr 20, 2009 7:36 pm
by Professor Science
But the kind of skeletal support structure for it may make it a good chunk heavier. But even moderate improvements on performance could make it for an interesting purely electrical air craft.
Edit: Upon further reading, the Biefeld–Brown effect which ionocraft exploit depends on High voltage DC which unless I'm mistake Polywells have in spades. yes?

Posted: Wed Apr 22, 2009 7:39 am
by MirariNefas
A 100 megawatt reactor just to lift 50 metric tons? Applicable only in the atmosphere, where we have various other options for achieving lift? Why would someone want to do this?

Posted: Wed Apr 22, 2009 12:04 pm
by Professor Science
Because it's never been done before? Weren't the original heavier than air flyers wildly less practical than ship or hot air balloons? It's just something that could be interesting to check out.

Posted: Wed Apr 22, 2009 7:14 pm
by MSimon
MirariNefas wrote:A 100 megawatt reactor just to lift 50 metric tons? Applicable only in the atmosphere, where we have various other options for achieving lift? Why would someone want to do this?
A 747 is roughly 100,000 hp (ie - 100 MW). But it weighs a lot more.

http://wiki.answers.com/Q/What_is_the_h ... Boeing_747

One engine is 125,000 hp.

Posted: Wed Apr 22, 2009 8:23 pm
by Professor Science
If you could improve the performances on ionocraft some advantages would probably be maintenance since there are no moving parts, noise pollution, maneuverability perhaps.

I'm not saying they're wonderful, just something nifty that would require power supplies like a polywell to run on the large scale.

Posted: Wed Apr 22, 2009 9:57 pm
by KitemanSA
Professor Science wrote:If you could improve the performances on ionocraft some advantages would probably be ... noise pollution, ...
Actually, this puppy might be VERY noisy. The general cause of noise in jets is the differential speed of the exhaust and the atmosphere. Where the difference in speeds are high, the jet is noisy. The ion-craft would probably have VERY high exhaust speeds, so may be very noisy.

Posted: Wed Apr 22, 2009 10:33 pm
by Professor Science
All small scale ionocraft are completely noiseless, I haven't seen video of any bigger than prox 10 cm across though. I'm thinking of building one with my EE friends.

Posted: Thu Apr 23, 2009 4:20 am
by D Tibbets
Pure speculation, but has the concept any application to levitation in sea water? Certainly the work needed to lift or balance a heavier than water submarine is much less than doing the same thing in air. And, there are certainly plenty of ions aviable. The problem might be too many ions- shorting out the system. If it worked, it presumeably would be much more stealthy than flooding or pumping out ballest tanks or possibly using fins. If the force was directed forwards it would again presumably be much quieter than a propeller. Is this anything like the silent drive popularized in the movie "Red October"? [Edit] Actually it is MHD, perhaps similar in princible?
http://en.wikipedia.org/wiki/Magnetohydrodynamic_drive

Dan Tibbets

Posted: Thu Apr 23, 2009 12:31 pm
by Professor Science
It works in any fluid, gas or liquid. The force is a product of Current times distance traveled, divided by how "movable" the medium is. you would just need to space the conducting parts far enough apart that they don't arc. that would be bad.

Noise...

Posted: Mon Jun 01, 2009 11:58 pm
by Nik
Um, from what little I've seen of ion-lifters, they *hiss* like electrostatic machines.

http://en.wikipedia.org/wiki/Electrostatic_generator
http://www.coe.ufrj.br/~acmq/electrostatic.html

If scaled, they may resemble cranky HV switchgear, and spit StElmo's Fire all over the neighbourhood.

FWIW, even domestic 'neg-ion generators' hiss, but you gotta get close...

Posted: Tue Jun 02, 2009 12:47 am
by Professor Science
With little theoretical basis I'm going to try incorporating a fractal pattern into the top, thin wire part, and see if it increases lift by increasing current flow without increasing mass too much. I'd like to read research on this matter, but I don't rightly know where to look. I know there's a japanese group doing stuff with it, but beyond that I'm in the dark.

Posted: Tue Jun 02, 2009 5:10 am
by MSimon
Professor Science wrote:With little theoretical basis I'm going to try incorporating a fractal pattern into the top, thin wire part, and see if it increases lift by increasing current flow without increasing mass too much. I'd like to read research on this matter, but I don't rightly know where to look. I know there's a japanese group doing stuff with it, but beyond that I'm in the dark.
Have you looked into fractal antennas?

Posted: Tue Jun 02, 2009 1:20 pm
by Professor Science
I heard about them on NOVA concerning fractals and it was one of those "well duh!" moments where you realize that makes an awful lot of sense. So I thought if fractals are used in nature to increase surface area to volume ratios and that's one of the things that effects corona discharge it could be worth exploring.