RE: Statistics & spark length and Air Pressure

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

Original poster: "Lau, Gary by way of Terry Fritz <teslalist-at-qwest-dot-net>" <Gary.Lau-at-hp-dot-com>

While the dielectric constant of air does vary somewhat with pressure, I 
don't think this is pertinent to breakdown voltage vs. length.

Terry posted a graph of static gap breakdown voltage with correction 
factors for air temperature and pressure.  Temperature had only a minor 
effect, but pressure was significant.
See http://hot-streamer-dot-com/TeslaCoils/Misc/SGapVolt.jpg

Consider how important low pressure is in plasma globes.

Gary Lau
MA, USA


 >Original poster: "by way of Terry Fritz 
<teslalist-at-qwest-dot-net>" ><dhmccauley-at-spacecatlighting-dot-com>
 >
 >The dielectric of air varies (increases) with increased air pressure.
 >However, I am thinking this characteristic would mostly apply only to
 >pre-breakout conditions.
 >I think once that the air is sufficently ionized by previous streamers, that
 >spark length vs. altitude would somewhat normalize and that air pressure
 >would be less of a factor.
 >
 >Any thoughts?
 >
 >The Captain