Re: Delta Fo (was How to raise secondary) Ion clouds (fwd)
---------- Forwarded message ----------
Date: Sun, 19 Jul 1998 18:25:42 -0400
From: Richard Hull <rhull-at-richmond.infi-dot-net>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: Delta Fo (was How to raise secondary) Ion clouds (fwd)
Tesla List wrote:
> ---------- Forwarded message ----------
> Date: Sat, 18 Jul 1998 13:44:54 -0700
> From: Jim Lux <jimlux-at-earthlink-dot-net>
> To: Tesla List <tesla-at-pupman-dot-com>
> Subject: Re: Delta Fo (was How to raise secondary) Ion clouds
> > ---------- Forwarded message ----------
> > Date: Sat, 18 Jul 98 12:13:38 EDT
> > From: Gary Lau 18-Jul-1998 1152 <lau-at-hdecad.ENET.dec-dot-com>
> > To: tesla-at-pupman-dot-com
> > Subject: Delta Fo (was How to raise secondary)
> > While I was ready to embrace the theory that the attached streamers were
> > responsible for adding to Ctop, the point raised that the streamers only
> > occur _after_ ringup pretty much discredited that in my mind.
> > Instead, what ever became of the theory that, in operation, an ion cloud
> > with a persistence greater than the bang interval, exists about the top
> > terminal, effectively increasing it's size and capacitance? Seems to
> > Gary Lau
> > Waltham, MA USA
> To get the ion density up to where it starts to make any real contribution
> to the conductivity of the air (and hence can make the effective size
> bigger) requires an air temperature on the order of 5000K, at which point
> the ionization will be obvious, because it will be glowing literally white
> hot. The ion density (and hence the conductivity) of air at 1 atmosphere
> pressure is a real step function of temperature. below a few thousand K,
> there is nothing to speak of, above 7000K, it is almost all ionized, and
> the transition is pretty fast. This is why sparks appear to have sharp
> edges. The current really only flows in the part that is hot and glowing,
> which heats the hot and glowing part even more.
> If you reduce the pressure, you can start to get an appreciable ionization
> from the E field, without resorting to the high temperatures.
We do not need real high current conduction to grossly affect the Ctop issue.
We don't even need small milliamp conduction! Both would just shunt the coil
out! We only need the alteration of the gas about the system to effect big
relative changes during ringup up of the next pulse. The 33 millisecond old
prior arc channel is still quite hot ionically and this is why the arc
persisits for a while. (multiple fire throughs of the same arc channel.).
When one consideres a plasma, regardless of pressure, the internal plasma /
ion temperature is a function of the potential gradient developed across the
plasma. If we assume only a lowly10 volt gradient through the entire arc
between, say, the terminal at one polarity and the target of the opposite
polarity during max current flow, then we are looking at 10 x ~11,000 (number
of degrees kelvin in a plasma per electron volt) or 110,000 degrees kelvin
for the ions at the very core of the arc channel!! It is probably much much
hotter. The real weird thing is that that is indeed at the real world honest
to god "hot" heat due to being near atmospheric pressure.
My deuterium loaded fusor easily hits 20,000 volts x ~11,000 or 220 million
degrees kelvin in the little 1/2" diameter poissor, but that is a cold heat
due to the 1 micron pressure.
Richard Hull, TCBOR