Re: Coupling vs secondary voltage chart

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Malcolm Watts" <m.j.watts@xxxxxxxxxxxx>

Hi Terry,
          Nice work on your program. I might be able to explain one
or two anomalies Steve noticed with primary current.

     I decided to plug my large SG coil figures into the program and
varied only the coupling from 0.05 to 0.25. "New Highs" were reached
as the coupling increased right up to k = 0.25 (the limit I set).

 _However_, it is clear from several runs that the outputs are
*heavily* dependent on the figure given for Rp. Intially I tried 2
Ohms which got barely 1J out of 3.2J to the secondary. I then tried
0.5 Ohms which did somewhat better which ended up with 1.95J (which I
think is still much too low) and Vc about 318kV which again I think
is on the low side (based on singleshot sparklength - I estimated
about 340kV).

      The moral of the story is that the primary resistance specified
is crucial to ouput accuracy. Finally, I did a run with Rp = 0.1
Ohms. Now Vc looks more in the ballpark (about 350kV) and load energy
got to 2.755J (certainly believable).

      Finally, I did another run, this time allowing k to climb to
0.5. Still the program kept finding New Highs, the last occurring at
k = 0.499. By this time though, load energy had dropped to about
2.74J despite Vc reaching about 387kV.

Some comments on the program:
      It would be nice if instead of reporting a bunch of new highs,
the program simply gave an output of best results (there might be
more than one) at the end of its run.
      I cannot understand how the coil gets to a higher output
voltage with a lower secondary energy.
      I didn't see any mention of sparklength in the output. This
would depend on breakrate and I didn't see any room for entering this
in the input file.
      For disruptive coils it would be nice if the program could
calculate a figure for Rp based on some function of primary current
(averaged if that is what is called for). That way there would be no
guessing.

     I would greatly appreciate you comments on any or all of these
points. I applaud the efforts of yourself and all those who have
contributed to the making of this program.

My regards to all of you,
Malcolm