Re: Streamer formation on the scope...

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

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


>
>Nice.  A probe artifact, or a genuine component of the discharge
>current?  You'll have to rig something up to generate an artificial
>current spike of similar duration to see if that excites ringing in
>the probe.  I'm happy to bet that this is a streamer resonance, and
>the frequency of it relates to the electrical length of the streamer
>in a transmission line fashion.
>
>Yes.  If the distributed reactance of the streamer dominates over its
>loss resistance, we should expect to see a spectrum of modes.  That
>would be very nice if so, because we could apply a transmission line
>model to the streamers.  The streamer becomes a lossy line to nowhere
>whose input impedance is seen by the topload.

I've always thought that dynamically varying transmission lines make a good 
analog for the fine structure behavior of streamers (yeah, yeah, I'm an RF 
kind of guy, and TLs are my life). I think that quasistatic approximations 
(the 220K+1pF/ft) kind of approximation works nicely for large scale 
modeling (i.e. fRes calculations).  But, for dynamic effects such as 
streamer growth, we need some sort of model for the actual streamer.

Bazelyan and Raizer (Spark Discharge) talk about various differential 
equation type models, some of which bear a striking resemblance to 
transmission line equations.