latest - Re: Ball Lightining

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

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi All,

I wound a new CW secondary coil that tunes properly.  The counter coil idea
worked "ok" but I really needed a new secondary...  I even have taps in it
now :-)  I fixed an ongoing problem with the generator's display
electronics and dealt with a few little fires :-)) but now the CW coil is
working and tuning perfectly.  

I should note that I found that the frequency of the secondary does
determine Fo but the coupling has a dramatic effect on the coil's input
impedance.  By rewinding the coil I got the Fo frequency right where I
wanted it (350kHz).  Then by spreading out or adding turns to the primary I
could get the input impedance right near 50 ohms for the generator by
working with the coupling.  So I ended up getting a good feel for matching
the coil's impedance to that of the generator.  A top load tends to reduce
streamer capacitive loading effects from lowering Fo excessively.

So I fired it up and got lots of nice flaming arcs:

http://hot-streamer-dot-com/temp/P1010015a.jpg

When the electrodes are close, they have the appearance of a big candle
flame.  Bright yellow with cooler orange borders.

http://hot-streamer-dot-com/temp/P1010023a.jpg

It is easy to get like a true flame going in the center of the arc as shown
above.  This is almost exactly like a candle flame in appearance as just
being a smooth steady flame.

As I spread the electrodes apart and used a flash to catch more detail,
One can see that the arc is actually a ribbon.

http://hot-streamer-dot-com/temp/P1010017a.jpg

When the arc stays in the same place, it seems to get much hotter.  With
the electrodes further apart, the flame gets far more distressed and you
see popping and such going on.

http://hot-streamer-dot-com/temp/P1010018a.jpg

I was not able to get fire balls like Ritchi but I have seen such balls on
a high power (8kW) power supply of the same basic type as my 900 watt unit
during arc testing.  The flame just seems to explode into a ball (there may
have been hot metal there).  I seem to almost be getting them but I just
need more power ;-))

The fire balls I have seen do seem to rise quickly from the heat and last
only a second.  They did not drift around as described for natural ball
lightning.  I would guess that the fire balls Tesla describes in passages
like Pages 379 to 381 of his Colorado Spring's notes ("Nolit 1978" version
opposite photo LIV) are the same as Ritchi and I describe.

I would guess that the "fire" is caused by super heated oxygen and nitrogen
decomposing into NOx compounds.  Oddly "my" coil never produces ozone or
NOx odors.  I don't know why not but I wonder if it's very harmonically
pure output tends to make odorless chemicals...  There is no doubt that the
temperature is "high"!  If you have enough energy concentrated, a ball of
flame my break away and burn on it's own feed by air currents briefly.  It
has been suggested that such a flame could feed itself for an extended
length of time but past a second seems to be unlikely IMHO.  A paper
dealing with this is at:

http://hot-streamer-dot-com/TeslaCoils/OtherPapers/Gladyshev/A%20Physico-Chemica
l%20Model%20of%20Ball%20lightning.htm  

That is supposed to be one line for the URL.  Or:

http://hot-streamer-dot-com/TeslaCoils/OtherPapers/Gladyshev/

Gladyshev's paper is the *.htm file.

If one were to add rain (and the chemicals in it), ozone, dust, dirt, etc.
of a rain storm into the mix.  Perhaps one could get a fire ball more like
those in nature.  I would guess they are the burning of available chemicals
at very high temperature in such a way that the burning is sustained by
convection currents.  This seems to be the direction those studying ball
lightning are headed.  Of course, some electrical arcs with hot metal added
can shoot such flaming balls too fed by the burning metal.  There are
probably a wide variety of fire balls fed by a wide variety of chemicals...

These tests should be reproducible by anyone with a 1500 watt or above
(preferably WAY above :-)) CW Tesla coil that can pump a LOT of power into
an arc to ground.  Space the electrodes as far apart as possible
(horizontal seems to work best).  The electrodes will get melting hot so
beware of fire!  Shorting the coil's output drops the impedance some but
not too much (I should have measured that 0:-p  All I had to do was push
the store to floppy disk button...) so it "should not" hurt anything.

Cheers,

	Terry


old
===========

Hi All,

I tried power arcing my CW coil as Richie describes.  I was only able to
pump about 200 watts delivered power into the arc since the generator was
not matching well.  I did not see anything like Richie's sparks but I think
I just did not have enough power.  I certainly do think it works, I just
need more power.  I made a movie of the arc.  It is 5Meg in size (sorry
about that).  Hot-streamer has 256kBPS upload speed.  You can see a lot in
the arc but just not enough power...

http://hot-streamer-dot-com/temp/capa1465.avi

This is using the DivX Codec 4.11

http://www.divx-dot-com/divx/index.php

It's the best most compressed video thing I know off.  The "codec" is some
sub program that allows video players to record and read it.

Even though I did not have enough power, I was pleased the technical video
stuff worked so well...  

Cheers,

	Terry


>Hi,
>
>The ball lightning folks might want to check out the "An unusual phenomena 
>frequently observed above power arcs." about two thrids down this page at 
>Richie's site:
>
>http://www.richieburnett.co.uk/sstate.html
>
>I have heard a lot of stuff about ball lightning over the years and this 
>looks like a very promising clue.  I'll set the "stuff" up tonight to see if 
>I can get it to work...
>
>Cheers,
>
>	Terry
>
>