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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.
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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.

ddn3, Jul 17 2010

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       Wouldn't the force of pushing the air away to create the vacuum barrier negate the reduced drag?
DIYMatt, Jul 17 2010
  

       The same could be said of the hypersonic torpedo, but it doesn't seem to be the case.   

       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.   

       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.
MaxwellBuchanan, Jul 17 2010
  

       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.   

       Can you give an example of ionized materials that currently can induce a vacuum on their surfaces?   

       For three bonus points explain how the "ionization repulsion" is communicated through the vacuum to the atmosphere that is repulsed.
WcW, Jul 17 2010
  

       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.   

       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..
ddn3, Jul 19 2010
  

       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?   

       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.   

       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.
MaxwellBuchanan, Jul 19 2010
  

       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.
ddn3, Jul 19 2010
  

       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.
MaxwellBuchanan, Jul 19 2010
  

       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.
ddn3, Jul 19 2010
  

       ^but your power usage would be immense and acceleration would be... lethargic.
DIYMatt, Jul 20 2010
  

       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.
FlyingToaster, Jul 20 2010
  

       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.
WcW, Jul 20 2010
  

       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.   

       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.
ddn3, Jul 22 2010
  

       //iconic propulsion// there's a tagline in there somewhere...
FlyingToaster, Jul 22 2010
  


 

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