Re: Optimal Quenching Tests

To: tesla-at-pupman-dot-com
Subject: Re: Optimal Quenching Tests
From: Jim Fosse <jim.fosse-at-bdt-dot-com>
Date: Sat, 25 Jan 1997 17:49:19 GMT
Subscriber: jim.fosse-at-bdt-dot-com Sun Jan 26 13:24:38 1997
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>Date: Thu, 23 Jan 1997 22:07:12 -0800
>From: Bert Hickman <bert.hickman-at-aquila-dot-com>
>To: tesla-at-pupman-dot-com
>Subject: Re: Optimal Quenching Tests

>> Well, if I can get pspice for almost free that sounds pretty good. One
>> question though: is it reasonable to put in one's own models for
>> things? You know, how do you build a model which works in pspice
>> for some arbitary device? And how does pspice actually do its compution
>> anyway?
>
>Sorry Ed, I just began playing around with this program recently, so I'm
>not familiar with its power. It does seem to have math functions and
>various voltage/current controlled sources that could be used to
>generate some models. 
>
>Is there anyone else on the list with significant PSPICE experience??
>
Not Moi,
>PSPICE solves network equations for node voltages, and can handle linear
>and non-linear devices and circuits. If you can generate a circuit model
>for the device (like a spark-gap) out of passsive and controlled-source
>devices, then PSPICE should be able to solve for the circuit behavior.
>DC, AC, and transient anaysis are all supported.
>

	But I'll throw this into the wind;)


----begin include from sci.plasma-----------------------------------

> The conductivity in ohm-m of a fully ionized plasma (which a flame is
> not) is
> 
>    5.2e-5 * Z * ln lambda / T_e^(3/2)
> 
> where Z is the charge of the ions, ln lambda, known as the Coulomb
> logarithm, is a weak function of density and temperature usually equal
> to 10 or 15, and T_e is the electron temperature expressed in electron
> volts (eV).  Thus a plasma is a poorer conductor than copper unless it
>X is hotter than about 1 keV (10 000 000 deg).  

>Another rule of thumb for radiating plasmas, is that its conductivity
>varies with the current  to the 3/2 power  I^(3/2a).   
>However, if really, really high voltage impulse is applied about a torus
>of plasma, the current electrons can be accelerated (run-away) to
>essentially light speed, and the conductivity of such plasma circuits
>may become several orders higher than ordinary copper conductivity.  

-------------end include--------------------------------------------

Notice the inverse T_e^(3/2) section: I think that this matches with
Malcolm et al's measured results.


	Welcome back Malcolm!

	A month of vacation (2 months) you luck dog;)

	cheers,

	jim