Ionic Breeze Propulsion - Will it work better on Mars ?

MarsDog · 2004-12-02 05:14:08

Could it http://www.rexresearch.com/desev/desev.htm]fly in low Martian Gravity ?

Or be used to generate electricity from the wind ?

Palomar · 2004-12-02 08:57:59

Or be used to generate electricity from the wind ?

*Well...if used on Mars, wouldn't we want to eliminate the need for a human passenger (added weight)? In a related thread, a NM member has said the winds of Mars aren't substantial enough to produce much power/electricity to begin with.

Have never seen this sort of thing before, though, so will defer further comments.

--Cindy

SpaceNut · 2004-12-02 12:42:38

That is a very interesting site MarsDog, could spend hours explore all those neat concepts. Magnetic motors or perceptual motion machines...
http://www.rexresearch.com

MarsDog · 2004-12-03 03:05:49

Ion engines achieve high exhaust speeds in low vacuum;
But only 3 to 4 meters a second on Earth. On Mars, pressures are lower, which would allow for a higher exhaust velocity.

0.96 hp. per pound, as compared with a typical 0.1 hp per pound of helicopter or 0.065 hp for a pound Piper Cub

I would like to see calculations for Martian conditions.

John Creighton · 2004-12-05 18:36:45

Ion engines achieve high exhaust speeds in low vacuum;
But only 3 to 4 meters a second on Earth. On Mars, pressures are lower, which would allow for a higher exhaust velocity.

This would be because the ions run into the air and slow down? But anyway the engine proves an interesting point. You can get a large amount of thrust with ions but maybe not with a high ISP as well. At least not with a modest power output. I heard the problem with ion engines was the current density. I wonder if the atmosphere helps to neutralize the ion stream to keep the current density lower.

MarsDog · 2004-12-06 20:04:18

I wonder if the atmosphere helps to neutralize the ion stream to keep the current density lower.

In a vacuum, long duration operation, the ion engine is power limited, and exhaust velocity is optimized for the power awailable.

In air, the limit is arcing between electrodes. There is a voltage at which a free electron collision with a neutral molecule creates another free electron. In addition, the ions colliding with the air, produce heat.

A pressure that pruduces few heat generating collisions would be optimum use within the atmosphere.

How to optimise? I have not figured it out.

John Creighton · 2004-12-09 13:19:45

In a vacuum, long duration operation, the ion engine is power limited, and exhaust velocity is optimized for the power awailable.
In air, the limit is arcing between electrodes. There is a voltage at which a free electron collision with a neutral molecule creates another free electron. In addition, the ions colliding with the air, produce heat.
A pressure that pruduces few heat generating collisions would be optimum use within the atmosphere.
How to optimise? I have not figured it out.

To minimize the problem of heat generation why not but the person above the ion grid and not bellow it as it is shown in the picture. To increase the ion speed put the electrodes further apart. That way the voltage can be increased more without back arcing.

MarsDog · 2004-12-09 17:09:05

On Earth, the distance a molecule travels in air, before collision, is several hundred times the molecular diameter. On Mars, it would be several hundred thousand, around 10^-5 meter.

Energy is shared between degrees of freedom;
without collision, most of the energy would remain in translation.

http://www.fordham.edu/Academics/Progra … 2.html]Gas Link for Molecular Freedom and Equality

The breeze velocity should be mutch higher on Mars, but the collision distance is still too short. Maybe a vacuum where the average collision is 0.1 meter, and the electrodes are similar distance apart ?

Euler · 2004-12-09 18:31:02

It seems this uses the http://en.wikipedia.org/wiki/Biefeld-Br … feld-Brown Effect. There are a few people who are still working on it, but there has not much progress on improving it's efficiency since the article was written. However, modern capacitors are light enough that a vehicle could be built using current technology which could lift its own power supply for a brief amount of time(a few seconds.) A lot of the fundamental physics involved are still not well understood.

Ion engines achieve high exhaust speeds in low vacuum;
But only 3 to 4 meters a second on Earth. On Mars, pressures are lower, which would allow for a higher exhaust velocity.
0.96 hp. per pound, as compared with a typical 0.1 hp per pound of helicopter or 0.065 hp for a pound Piper Cub
I would like to see calculations for Martian conditions.

You actually want the exhaust velocity to be low, since that will increase the amount of thrust you get per unit of energy. However, if you try and get the velocity too low, you will end up without producing a significant amount of thrust. Another thing you have to consider is that the size and shape of the coronal glow would change due to the reduced amount of pressure. So how would a optimized Martian ionic breeze system compare with an Earth ionic breeze system? I don't really know, and I have not been able to find any sources that give a clear answer on that question. Anyone have a vacuum chamber that you can use for some experiments?

ERRORIST · 2004-12-09 20:56:57

Perhaps, you can use on old power plant condenser and hotwell.

GCNRevenger · 2004-12-09 21:47:39

Perhaps, you can use on old power plant condenser and hotwell.

Ummmm. No. Nowhere near enough energy storage.

John Creighton · 2004-12-10 08:55:35

http://www.google.ca/search?q=cache:vIJ … ...2&hl=en

http://science.slashdot.org/science/04/ … ...tid=137

http://www.ioffe.ru/RT/IWRFRI2000/b28p. … /b28p.html

http://topics.practical.org/browse/nucl … -batteries

http://www.spectrum.ieee.org/Scripts/sp … ...ortdate

Euler · 2004-12-10 13:17:50

I don't think that any of those would help unless the efficiency of the ionic breeze engine improves substantially. You need a high specific power, rather than just a high specific energy.

John Creighton · 2004-12-10 14:58:55

I don't think that any of those would help unless the efficiency of the ionic breeze engine improves substantially. You need a high specific power, rather than just a high specific energy.

How about just making the array lighter. Maybe even make the array lighter then air.

Euler · 2004-12-11 22:13:52

How about just making the array lighter. Maybe even make the array lighter then air.

If the power supply by itself has a higher weight than the thrust that the crafts generates, then you will not be able to make it fly by simply reducing the mass of the array. I suppose you could use it to propel an airship, but this technology would have to improve a lot before it could become competitive with propellers.

MarsDog · 2004-12-12 10:44:41

There is a fundamental problem with the ionic breeze.
Above a certain voltage gradient http://www.blazelabs.com/ionocraftdesign.pdf]avalanche breakdown.

But unexpectedly, replacing your computer http://www.ee.washington.edu/research/s … cs.pdf]fan, in the future ?

The next step is to read up on http://www.aeronautics.ru/plasmamain.htm]plasma.

John Creighton · 2004-12-12 11:08:10

If the power supply by itself has a higher weight than the thrust that the crafts generates, then you will not be able to make it fly by simply reducing the mass of the array. I suppose you could use it to propel an airship, but this technology would have to improve a lot before it could become competitive with propellers.

II thought about why not just use a propeller like an air ship. Clearly the ratio of power to weight will depend on the power source and we do not have a suitable power source. The only real advantage I see the ion source has over a propeller is perhaps less drag. If the craft is just blowing in the wind then why not a propel but if the craft is going fast then the wind just breezes right though it. There is no propeller to get in the way. Maybe other shapes are possible. I considered a shape kind of like an f177 stealth fighter (the one big wing idea) but with a big duct under neat it. The point is the longer the duct the more time the ions have to accelerate, and the less collisions there will be from sucking air from the side into the exhaust path. Moreover, the air flowing though the duct should be hotter and thus perhaps lighter then the surrounding air giving buoyant lift. What kind of supper light structures can we build. We know of foams. What if we make miniature tube shape balloons out of carbon nanotubes and pack them together. What kind of structural properties will that have. In the outer layer of the tubes the radius will be smaller and containing gases of greater pressure and the inner layer of tubes will be at a lower pressure with a larger radius. I have more ideas and perhaps they are all dead ends but I think there are a lot of possibilities here. I will point out the bigger the array the more efficient it can be made especially if it is lighter the air.

John Creighton · 2004-12-12 11:19:01

Okay for a second imagine you can build a huge array light enough to build an air ship lifting up the airship instead of a balloon. Because the array is just a bunch of tubes instead of a solid sphere it will probably be bigger then the balloon. Say it is in the shape of a show box big enough to contain four airship balloons. To Make it heaver then air the balloons must be squeezed together. The air ship takes off and fires its fans and once the airship gets up to the maximum speed the propellers can take it the array starts to significantly drag the airship backwards just like the balloon. Now the airship turns on the airship thrusters and the wind just breezes though the balloon like it is not even there. The balloon now starts to balloon the airship forward. There is a red glow behind the airship and the expanding air behind the airship almost pushes it forward faster. The airship then turns up the speed of its fans to match the ion thrusters and so on. Now if the airship was sandwadiged between two arrays then it would not need fans to match the thrusters. I think there might be a point here. The ion thrusters may accelerate shower then a fan pushing a balloon but they will have considerably less drag. Perhaps if the air was lighter then air by enough to support its own power source it could just gradually accelerate and accelerate. Almost as if the air wasn’t there. Okay I am sure there are a lot of weeks spots in what I wrote. Begin poking holes.

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#1 2004-12-02 05:14:08

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#2 2004-12-02 08:57:59

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#3 2004-12-02 12:42:38

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#4 2004-12-03 03:05:49

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#5 2004-12-05 18:36:45

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#6 2004-12-06 20:04:18

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#7 2004-12-09 13:19:45

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#8 2004-12-09 17:09:05

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#9 2004-12-09 18:31:02

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#10 2004-12-09 20:56:57

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#11 2004-12-09 21:47:39

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#12 2004-12-10 08:55:35

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#13 2004-12-10 13:17:50

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#14 2004-12-10 14:58:55

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#15 2004-12-11 22:13:52

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#16 2004-12-12 10:44:41

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#17 2004-12-12 11:08:10

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

#18 2004-12-12 11:19:01

Re: Ionic Breeze Propulsion - Will it work better on Mars ?

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