Re: Structrual support, was: oil dielectric, ozone production

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Xyme3-at-aol-dot-com>

In a message dated 05/27/2002 1:07:09 PM Pacific Daylight Time,
tesla-at-pupman-dot-com writes:


>
> If you instead tried to use a metallic coil form, even if insulated by
> some type of coating, the coilform will behave as a big short-circuited
> turn, introducing huge system losses that are virtually independent of
> the form's magnetic properties. Even slitting the pipe lengthwise to
> break the "loop" doesn't help much, since you still develop significant
> internal RF "eddy currents" within the form which sap large amounts of
> energy from your system, converting it to heat instead of streamers. But
> even if you were capable of developing significant voltage across the
> secondary winding, the relatively thin insulation between the winding
> and the conductive coil form would break down, short-circuiting the
> secondary winding. PVC is cheap and it'll work for all but the most
> stringent coiling applications.


Bert,
Thank you for the information. Ceramic would solve the problem of heat being
transferred from the metalic core, however the system loss you describe is a
concern. You mention specifically the secondary winding and the thin insulation
between it and the metallic core breaking down. Is this less of a concern in
the primary? If only one metal core was inside the primary were used, would
system losses be half as much?  How about if an iron core was only inside the
secondary?

My questions stem from readings about St. Elmo Fire devices. In this particular
coil an iron core was used for the primary winding. The iron core was inserted
inside the secondary ( which was wound around an iron pipe?) until an
electronic flame or  brush was produced. The flame produceing electrode
attached to the external secondary. One passage stated that iron was more
permable at higher temperatures thus produceing a better brush. In specific
ozone production was mentioned as a by product. Ozone has been approved for
sterilization of food in place of chlorine. 
Paul