Working with EM Fields

[Travis Box]

I'm trying to find a substance that I can use to make a relatively
small container that will withstand internal pressures of up to 75psi,
and that will not affect any EM fields around it. In fact, I want the
EM fields to pass through it as simply as possible, without affecting
the flow of the fields. Would I need something that is very
electro-conductive, or something that is electrically neutral? Any
suggestions?

 

[John Larkin]

I'm trying to find a substance that I can use to make a relatively
small container that will withstand internal pressures of up to 75psi,
and that will not affect any EM fields around it. In fact, I want the
EM fields to pass through it as simply as possible, without affecting
the flow of the fields. Would I need something that is very
electro-conductive, or something that is electrically neutral? Any
suggestions?

Plastic; polycarb maybe. Metal would shield/reflect EM stuff.

John

 

[John Woodgate]

I read in sci.electronics.design that Travis Box

I'm trying to find a substance that I can use to make a relatively
small container that will withstand internal pressures of up to 75psi,
and that will not affect any EM fields around it. In fact, I want the
EM fields to pass through it as simply as possible, without affecting
the flow of the fields. Would I need something that is very
electro-conductive, or something that is electrically neutral? Any
suggestions?

You need a good low-loss insulator. Polythene or polypropylene for high
frequencies, but whether you could get safety approval for 75 psi,
however thick the walls were, is another matter.

What frequency range do the fields have? For low frequencies (less than
1 MHz) there is a much wider choice of materials.

 

[Travis Box]

I read in sci.electronics.design that Travis Box


You need a good low-loss insulator. Polythene or polypropylene for high
frequencies, but whether you could get safety approval for 75 psi,
however thick the walls were, is another matter.

What frequency range do the fields have? For low frequencies (less than
1 MHz) there is a much wider choice of materials.

the idea I have is to design a lifter device that utilizes the
biefeld-brown effect and is contained in a (relatively) pure
environment of Sulfur Hexaflouride (SF6). According to the research
that I've looked at, if I maintain an internal pressure of approx 5
atmospheres, or roughly 73.5psi of SF6 the electro-conductivity of the
environment should be reduced to about a tenth of dry air (at sea
level) which should allow me to reduce the amount of wire gap between
the wire and the foil to a tenth of what was previously required to
prevent arcing between the wire and the foil. Doing this should
multiply the Newtons of thrust that the device outputs by roughly 56.
These measurements were done using a lifter simulator from Blaze Labs
( www.blazelabs.com ). If my assumptions are correct, then a simple
lifter composed of 3 levels that each contain a cell shape composed of
12 cells would output 56.3527N of thrust and have an upwards
acceleration of 1117m/s^2 and a terminal velocity of 2181.86 m/s.

 

[Mac]

I'm trying to find a substance that I can use to make a relatively
small container that will withstand internal pressures of up to 75psi,
and that will not affect any EM fields around it. In fact, I want the
EM fields to pass through it as simply as possible, without affecting
the flow of the fields. Would I need something that is very
electro-conductive, or something that is electrically neutral? Any
suggestions?

Are you talking about static or dynamic fields? Since you say EM, I guess
you mean dynamic fields? Ideally, you need something that has permeability
and permissivity equal to air. I don't know of such a substance. In the
absence of such a substance, you might try a decent dielectric, like PVC
or ABS pipe. These should have no problem with 75 PSI. More expensive
options include polycarbonate, teflon, and aramid fiber(kevlar)/epoxy
composite.

I read further down where you want to put Sulphur hexafluoride in the
pipe. That sounds like it might be a potent oxidizer, and might attack the
plastics. But I believe the teflon would withstand it easily. Then again,
I don't know much about chemistry.

Let us know what you use and how it works out.

--Mac

 

[John Woodgate]

I read further down where you want to put Sulphur hexafluoride in the
pipe. That sounds like it might be a potent oxidizer, and might attack
the plastics. But I believe the teflon would withstand it easily. Then
again, I don't know much about chemistry.

SF6 is extremely inert, which is why it's used as an insulator in high-
power transmission equipment.

 

[Kevin Aylward]

multiply the Newtons of thrust that the device outputs by roughly 56.
These measurements were done using a lifter simulator from Blaze Labs
( www.blazelabs.com ).

Ho hum, a right bloody crank. Complete drivel. The writer of this is
completely clueless about physics.

Fist google on biefeld-brown
http://jnaudin.free.fr/html/nasarep.htm
http://www.fact-index.com/b/bi/biefeld_brown_effect.html


Me thinks someone is wasting ones time, along with all those other Joe
Newman followers.

Kevin Aylward
[email protected]
http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.

http://www.anasoft.co.uk/NewBeginning.mp3

"quotes with no meaning, are meaningless" - Kevin Aylward.

 

[Klaus Bahner]

the idea I have is to design a lifter device that utilizes the
biefeld-brown effect and is contained in a (relatively) pure
environment of Sulfur Hexaflouride (SF6). According to the research

Well, as far as I understand it the Biefeld-Brown effects relies on the
corona discharge (to create the ion wind) at the smaller electrode,
appearently the top wire in those "lifters". SF6 basically prevents any
corona discharge from happening (at least at moderate HV levels below
several 100 kVs or so). Provided my understanding of the Biefeld Brown
effect is correct, embedding the whole "lifter" in SF6 will actually
make the effect vanish or at least reduce its strength.

Encapsulating only the electrodes and filling it with SF6 or whatever
dielectrics may allow you to increase the breakdown strength, but in my
opinion you also make the Biefeld-Brown effect vanish, because any
enclosure around the electrodes isolates the ion winds mechanically from
the environment - hence no thrust at all will be generated. Besides that
I don't think that this will work at all, the requirements for the
material you are looking for are quite simple. There is no magnetic
field involved in the Biefeld-Brown effect and the electric field is
just an electrostatic field. To fulfill your requirements look for an
insulator with high breakdown voltage and long term stability and a the
lowest possible relative permittivity (in case you require maximum
"transparency" for the electrostatic field, which by the way makes the
use of SF6 questionable).

that I've looked at, if I maintain an internal pressure of approx 5
atmospheres, or roughly 73.5psi of SF6 the electro-conductivity of the
environment should be reduced to about a tenth of dry air (at sea

Well, only if the SF6 is dry. When you buy SF6 it usually still contains
quite a bit of water - do you have the equipment to dry it?

Klaus

 

[Mac]

SF6 is extremely inert, which is why it's used as an insulator in high-
power transmission equipment.

Thanks for the info. I know sulfur is an oxidizer, and fluorine is the
mother of all oxidizers, so I thought the two together would still be a
potential oxidizer. I guess I was wrong. Probably there is too much energy
in the S-F bond for it to break easily, thus ensuring that neither sulfur
nor fluorine are available to react with anything else.

--Mac

 

[Klaus Bahner]

Thanks for the info. I know sulfur is an oxidizer, and fluorine is the
mother of all oxidizers, so I thought the two together would still be a
potential oxidizer. I guess I was wrong. Probably there is too much energy
in the S-F bond for it to break easily, thus ensuring that neither sulfur
nor fluorine are available to react with anything else.

--Mac

Both is true. SF6 is extremely inert and does usually not react with
anything, but in case of arcing in a SF6 insulated system a whole bunch
of extremely obnoxious substances are generated, which can attack both
equipment due to corrosion and your health. The amount of breakdown
products is usually only in the ppm region, but this is still enough to
cause reactions on metal surface and to cause irritations of your lungs
etc. If water is present these problems get worse, one of the reasons
why one tries to work absolutely dry, when using SF6.

Klaus