Tesla Coil Optimun Parameters (was Wire length,resonance, Q)

From:  John H. Couture [SMTP:couturejh-at-worldnet.att-dot-net]
Sent:  Wednesday, May 27, 1998 1:15 AM
To:  Tesla List
Subject:  Tesla Coil Optimun Parameters (was Wire length,resonance, Q)

  Jim, All -

  Determining the optimun parameters for a Tesla coil is certainly a
challenge. But why do it the hard (or impossible) way? The Corum's in their
writings have shown the fourth order differential equations for Tesla coils.
But this is a long way from ending up with a spark length output.

  Tesla coil design is empirical meaning both theory and test results are
required. We have the theoretical equations and can find the empirical
equations based on tests. Why not set up some typical TC input parameters
and do the calcs that will end up with a spark length. When the coils are
built and tested if the spark length is different then change the empirical
equations and calcs.

  All complex engineering projects are done this way, including the design
of locomotives, steamships, aircraft, space shuttles, etc. If enough coilers
work on this type of empirical design program (manual or computer) and build
and test enough coils we would soon have an acceptible method of determining
the TC optimun parameters. Computer programs like the JHCTES are a start in
this direction.

  John Couture


At 10:00 PM 5/25/98 -0500, you wrote:
>From:  Jim Lux [SMTP:jimlux-at-earthlink-dot-net]
>Sent:  Monday, May 25, 1998 10:39 AM
>To:  Tesla List
>Subject:  Re: Wire length,resonance, and Q (fwd)
>>  > Going forward;
>> > This thread is always interesting when it comes up from time to time.
>The big
>> > question which I keep asking myself is, "What are the optimum
>parameters?" as
>> > John hinted towards. I wonder if there is really is an optimum. It
>appears that
>> > each coils optimum setting is unique to the geometry, size, power
>levels, ground
>> > plane, and a host of other variables.
>> > 
>> They are pretty conflicting: A high secondary reactance to yield a 
>> high voltage, a low secondary reactance to yield a high current. 
>> Using a large top C removes the burden of the low reactance 
>> requirement from the resonator itself. However, Vout can only reach 
>> what Es and top C will allow.
>Of course, "optimum" implies that there is some attribute (or combination
>of attributes) that one wants to maximize (or minimize). Just what might
>that be? Given most comments, I suspect that what people want out of their
>coils is long sparks.  
-----------------------------  Big snip

>My gut feel is that the dimensions of a typical coil are so tiny compared
>to a wavelength, that the lumped approximation should be more accurate.
>This is good, because it means we can do the calculations of leader growth,
>etc, using a fairly straightforward set of differential equations, which
>can be numerically integrated.