Re: Corona and Sphere - Puzzle -addition

Boris, and all,

Some other thoughts...
Once a streamer has formed, the peak terminal voltage on sucessive
"bangs" will not reach the levels prior to breakout due to the fact that
more energy/bang is being transfered into the streamer earlier in
resonator ring-up. I also find that, prior to breakout, a blue "haze" of
corona surrounds the outer region around my top terminal. However, once
breakout occurs, this seems to go away. But this may simply be an
optical illusion due to the brighter streamers swamping out the much
fainter corona.

-- Bert --

Tesla List wrote:
> Original Poster: boris petkovic <petkovic7-at-yahoo-dot-com>
> Let us consider behavior of smooth sphere excited by
> TC h.f wave form.Let sharp point be added at one side
> of sphere to allow issuing of spark.Let be considered
> only single pulse mode.Let diameter of  sphere be
> 10".When voltage on sphere reaches 300-350 KV sphere
> should discharge in all directions in air,not only
> through already formed sharp point path judging by
> experiments of the same sphere without sharp point
> added.However,it proceeds to discharge through sharp
> point path despite voltages of 400 KV or more.At last
> when voltage in the order of 500 KV is reached ,sphere
> would start to form another streamer paths from its
> surface but even then those new streamers are not
> reaching so far distances as very first one ..In all
> the books can be found data the most responsible
> factor for breaking down of air is strenght of local
> electrical field (which is ~30 KV/cm for DC ,low
> frequency range or even somewhat lower for TC h.f
> range).But before forming new streamers el.field
> reaches 40 KV/cm in described case!
> I got as the same explanations like some of yours  as
> I got from some physicist and HV engineers:Well ,you
> see the sphere electrode already discharges through
> adjanced sharp point path..or formed streamer offers
> less impedance than rest of surrounding air.."But when
> I formulated the problem like follows:
> Half of sphere with adjanced wire point is situated in
> black box (so you cannot seen if discharging occurs
> there or not),another half of smooth sphere is exposed
> and can be seen .When powered by TC you can measure
> strenght of el.field >40 KV/cm and nothing
> (caracheristic visible corona doesn't appear).The
> question :How do charges at exposed side "know" that
> discharging already occurs in the black box and follow
> that path instead of forming new streamers despite
> more than sufficient el.fields reached?What mechanism
> determines and allow such behavior (I know it is
> powerful streamer in the black box but what
> exactly?).After that some of them start scraping their
> heads...The problem is not as simply as someone may
> think.Anyway thanks for thoughts/tries.
> Regards,
> Boris