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Re: Power versus Spark Length




From: 	John H. Couture[SMTP:couturejh-at-worldnet.att-dot-net]
Sent: 	Monday, July 21, 1997 2:07 PM
To: 	Tesla List
Subject: 	Re: Power versus Spark Length

At 08:16 AM 7/21/97 +0000, you wrote:
>
>From: 	Greg Leyh[SMTP:lod-at-pacbell-dot-net]
>Sent: 	Sunday, July 20, 1997 2:49 PM
>To: 	Tesla List
>Subject: 	Re: Power versus Spark Length
>
>Tesla List wrote:
> 
>> From:   John H. Couture[SMTP:couturejh-at-worldnet.att-dot-net]
>>
>> >From:  Malcolm Watts[SMTP:MALCOLM-at-directorate.wnp.ac.nz]
>> >
>> >> From:   John H. Couture[SMTP:couturejh-at-worldnet.att-dot-net]
>> >>
>> >> 2. Increasing/decreasing the secondary coil inductance would
>> >> increase/decrease the spark length.
>> >
>> >Why? 
>>        
>> Because of  Vs = Ls di/dt
>
>
>If you believe that di/dt remains constant while changing Ls, then 
>why not make Ls as large as possible?
>-------------------------------------

I do not believe that di/dt remains constant. This is involved with #3 of my
post. 

-------------------------------------
>Regarding Vs,  I believe that if one applies Occam's Razor to the
>problem, a simple equation ultimately determines the output voltage:
>
>Energy in Csec = (energy in Cpri) X (coil efficiency)
>
>The _only_ assumption that this equation relies upon is that energy
>is always conserved.  Given that E = 1/2 CV^2, the output voltage
>immediately follows from this equation.
>
>Comments?
------------------------------------------
 
  There is no way to measure the energy in the TC system that produced a
single special long spark. How would  you measure the actual voltage that
the Cp is charged to for that certain spark? Also, how would you determine
how many breaks were required before the Cp had enough voltage to fire the
operating spark gap? An osilloscope could not do the job. 

  However, if you use averaging methods rather than one shot methods, you
can measure the watts input for a number of sparks over time (energy) and
use the following equation. In this setup the Cp voltage is averaged over a
time period.

  Input W = .5 Cp Vp^2 BKS / Eff       (Per second)

 The energy output would be represented by the length of horizontal
continuous sparks (controlled sparks) from the secondary terminal to a
ground point. 
 
I admit this still leaves alot to be desired but is better than what we are
now doing.

--------------------------------------- 

>-GL
>
 John C.
>
>