Re: Toroid or sphere?

[Terry Fritz <twftesla-at-xxxxxxxxxx>]

Hi John,

At 02:39 PM 11/21/2000 -0500, John Freau wrote:
snip...
>
>Ball electrode can form straight single streamers that come
>straight off the top of the ball at times, if the ball, and other
>conditions are right.  Toroids throw the sparks outwards.
>

At first, I was confused by this.  But I remember seeing pictures of Duane
Bylund's coils where streamers are indeed coming straight up from ball
electrods.  I ran a stress model:

http://hot-streamer-dot-com/TeslaCoils/Temp/sphere.gif

That shows the field stress is apparently a tiny bit less right at the top
of a sphere (I wonder if the stres model is introducing an error along the
center??).  However that is not the full story.  I think, much like a
Jacob's ladder, the heat from a streamer goes up and guides the streamer to
a path directly above the terminal.  I think people have mentioned that the
streamers off spheres tend to go outward but sometimes will change to a
straight up streamer after running a bit which would support this idea.

FWIW...

Cheers,

	Terry