Re: desirability of high coupling...Re: primary INSIDE of secondary?

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

Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz <teslalist-at-qwest-dot-net>" <acmq-at-compuland-dot-com.br>

Tesla list wrote:
 >
 > Original poster: "Jim Lux by way of Terry Fritz <teslalist-at-qwest-dot-net>" 
<jimlux-at-earthlink-dot-net>

 > Bazelyan and Raizer mention streamers forming from very high voltage DC
 > sources (>1MV) and being a enduring phenomena:
 > " Quite different is the corona behavior in a gap with large electrodes. As
 > the voltage rises, the continuously glowing envelope breaks up into
 > separate patches, in which longer filaments, fancifully shaped channels of
 > cold light, appear and disappear again within a few microseconds.....  A
 > streamer corona produced in a large air gap at voltages above 1 MV looks
 > like fireworks. A streamer may be as long as several meters; numerous
 > bright streamer channels cross the dark space of the laboratory room with
 > such a noise that the experimenter can not hear his own voice.  The pulse
 > current of a propagating stremer only lasts for a few fractions of a
 > microsecond and is measured in amperes, even in tens of amperes. ... If the
 > laboratory voltage source permits, a streamer corona an be observed lasting
 > for many hours.  It does not lead to short circuiting, because, for this,
 > it is necessary that the streamer channels cross the whole gap space, which
 > normally occurs in atmospheric air at an average field of about 5 kv/cm."

This description appears to be related to a kind of streamer that I call
"failed spark", that can be generated by an electrostatic machine when
the
spark terminals are a bit beyond the maximum sparking distance. It is
a weak spark with a "puff" sound, that doesn't discharge the terminals
completely. Apparently a "charge packet" that travels from one terminal
to the other without the formation of a spark channel. When strong
enough
to be visible, they are strongly ramified in the direction of the
negative
terminal. If the power supply can keep the terminals charged, I believe
that these "failed sparks" can generate something that resembles a
Tesla coil streamer, but this would require very high power.

 > One of B&R's more poetic passages.. clearly they are impressed by the
 > appearance, and these are guys who make 100m+ discharges at many MV
 > and many MJ

High power...

 > >The effects of the envelope on streamer development are still
 > >mysterious,
 > >I think. The detuning when the streamers develop may be not a so serious
 > >problem if the coupling is high. And even with low coupling, the system
 > >may "tune itself" to a certain average streamer length.
 >
 > The more this gets discussed, the more I think about figuring out how to
 > make a numerical model of the entire system, including the spark channel..

Complicated, but not impossible. Probably someone already have the
right models developed.

Antonio Carlos M. de Queiroz