Re: Explanation of K

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

Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz <twftesla-at-qwest-dot-net>" <acmq-at-compuland-dot-com.br>

Tesla list wrote:
> 
> Original poster: "Paul Nicholson by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <paul-at-abelian.demon.co.uk>

> Antonio, don't forget, real coils don't follow the lumped model,
> and it is dv/dx not dv/dt that you have to worry about.

Well, they follow as well as the limited model can predict.
I see that high-order resonances in the distributed system of the
secondary coil can be excited by the sudden application of the
primary voltage, and agree that dv/dx irregularities (waves)
can appear. But I would like to see a study about how are these 
waves in function of the coupling coefficient, to verify if they
really are significantly larger when the coupling coefficient
is high. An experimental verification could then solve the
"racing sparks" puzzle.
 
> Consider the consequences of, say, the 5/4 wave mode having 10%
> the amplitude of the fundamental modes.  This puts 10% of the
> top volts across 20% of the coil, thus adding up to 50% to the
> existing dv/dx of the fundamentals.

This makes sense, but would the relative amplitudes of the
modes be much different for different coupling coefficients?
The lumped model predicts that with higher coupling what happens
is essentially that the secondary voltage rises to the maximum
in less cycles. dv/dt and di/dt peaks are not much affected
(they are proportional to the secondary current and voltage,
and these are limited by energy conservation). The maximum 
dv/dt really increases with k (due to the different relation
to di/dt and due to smaller losses), but not much. Would the 
peak of dv/dx increase significantly with k?

> Similar occurs when a Tesla secondary is 'struck' into resonance
> by an impulsed primary.  For a typical TC, the higher modes are
> less than 5% of the fundamental amplitude.  Increasing the
> coupling raises this fraction. 

Where is this result shown in your investigation (excellent,
by the way)?

Antonio Carlos M. de Queiroz