h a l f b a k e r yContrary to popular belief
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Ionic Slipstream Assist
Using ionizing skin, an aircraft repels the ionized air strongly enough to create a vacuum to slip through. | |
So there is an interesting weapon the Russians develop
(Shkval-Torpedo), the hypersonic torpedo, which rides
within a vacuum bubble caused by hypersonic caviation.
This allows the torpedo to travel at enormous speeds
underwater, which goes against logic since water is so
much denser than air.
So
I was thinking would it be possible to create a similar
vacuum bubble around an aircraft? There have been
experiments where people have attached suction devices
to wings to change the airfoil profile and its shown to
decrease drag and improve fuel efficiency, so the idea
might work.
One idea is to coat the aircraft with a strongly ionizing
material, either naturally ionizing (some sort of
radioactive material) or electro active material. It
ionizes
the air so strongly that it might give off a glow, this air
is
then repulsed away from the skin of the aircraft quickly
enough to create a vacuum barrier (albeit small one) but
enough to reduce the crafts drag allowing it to slip
through
the air.
[link]
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Wouldn't the force of pushing the air away to create the vacuum barrier negate the reduced drag? |
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The same could be said of the hypersonic torpedo, but it
doesn't seem to be the case. |
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I think the argument is that, if you open up a bubble and
then close it again (behind the vessel), the net energy
expenditure is close to zero. |
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There should be some combination of velocity and scale at
which air behaves analogously to water, but I have no idea
what it would be. |
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in water we can have cavitation because water is a fluid. in an airfoil we can improve the shape and reduce turbulence but it is not possible to push through the air by any mechanism without doing work (spending energy). Whenever a mechanism to completely avoid the consumption of energy is proposed we must question the underlying implications. If we are doing work ("pushing") with an ionized field are we likely to conserve energy ("thrust") or waste it? If we can control this very powerful displacement of air then how is this not a form of propulsion on it's own? If so then how does it's efficiency compare with that of the conventional propulsion. |
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Can you give an example of ionized materials that currently can induce a vacuum on their surfaces? |
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For three bonus points explain how the "ionization repulsion" is communicated through the vacuum to the atmosphere that is repulsed. |
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The ionizing affect is so we can utilize magnetic
fields to repel them from the surface of the craft
strongly enough to create a temporary vacuum
layer between the aircraft and the atmosphere.
Normal non-inoinzed air cannot be affected by
magnetic fields or any repelled in any other way
than direct manipulation (ie fans). Once the
aircraft reaches high enough velocities I suspect
this ionization becomes self sustaining just due to
the speed. |
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A strongly radioactive material emitting alpha
particles can ionize the air but only on the
surface, which is exactly what we want. Once the
air is sufficiently ionized, powerful magnets
underneath the aircraft skin will repel the ionized
air away creating a vacuum skin. That's the theory anyways.. |
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I dunno. You have to push air away; why is it more
efficient to do it this way than having it displaced directly
by the fuselage? |
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Suppose your system worked perfectly. The air would
"see" the magnetic field and be pushed aside by it, just as
it would normally "see" a solid surface and be pushed
aside. So I don't see the energetic advantage. |
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The hypersonic torpedo works simply by displacing the
water in a special way, using its own speed and special
shape to do so. I think you'd need to do the same thing
for the aircraft. The fact that air is highly compressible
may prevent this sort of effect. |
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Because when you move through the air the air
atoms stick to the skin of the craft causing drag and
such. By repelling the air away from the skin of the
craft with this thin layer of vacuum, you in theory
greatly reduce its drag, allowing it to slip through the
air. Fish do this as well, they secrete a layer of
"slime" which acts like this barrier except so the
water doesn't touch the fishes skin directly and the
slime smooths out any imperfections in the fish skin
allowing it to greatly reduce drag. |
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Yes, you're right as far as skin-drag goes - fair point. I was
thinking more of form drag, which is a different banjo of
bees. |
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Yes , for form factor the simplest shape suited for
this of course would be the saucer. I suspect this
technology is already being deployed in top secret
skunkworks. If you can reduce the drag down to
1/100 of a conventional aircraft, u might be able to
use ionic propulsion to push it, thus freeing up the
need for large bulky jets and turbines. |
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^but your power usage would be immense and acceleration would be... lethargic. |
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k, so what kind of power are we talking about to, say, decrease the air density adjacent to a square inch of surface at sea level by half: "all we have to do" is minimize surface drag. |
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the basic idea is bunk. a magnet moving in a magnetic medium is going to suffer from drag. the air cannot be displaced without doing work. you get the bonus however. |
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I'm not suggesting you use iconic propulsion to
push the craft, I'm suggesting you repel ionized air
away from the crafts skin to reduce drag, allowing
it to slip through the air. And even then I doubt
you could continuously sustain the vacuum, it
would have to be pulsed. Yes there could be
magnetic drag, but the ionized air propelled away
from the craft will quickly de-ionized colliding with
non-ionized air losing its magnetized state. So its
all relative, is the drag from the magnetic fields
more than the normal drag from a fast moving
aircraft? If its less, then its a win. |
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Though its an interesting idea to use
the ionized air to propel the aircraft, but I
wouldn't
know the physics for that. Even then it's not the
ionized air which is reducing the drag, its the
vacuum bubble it creates akin to the original
inspiration the Shkval Torpedo. |
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//iconic propulsion// there's a tagline in there somewhere... |
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