Tesla simulation software project

["Paul" <paul-at-abelian.demon.co.uk> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

In view of the current interest in estimating resonant frequencies,
members of the list may be interested in an ongoing software project
concerned with modeling of tesla resonators.

There are two programs involved,

1/ tlap.c

This program computes the various external capacitances of the
tesla resonator by computing the E field in a spacial resolution of
1mm out to a radius of 3m from the coil, and to progressively lower
resolution out to a distance of 24m using multigrid methods and
a varying cell size across the field. Techniques are employed which
simulate boundaries at infinity (ie the sky) where required.
A continuous graphic display is maintained by the program which shows
the field as it evolves during the computation.
The toploading capacitance and coil capacitance profile
are computed and used as input to the second program.

2/ tsim.c

This program models the operation of the tesla resonator using
a cascade of several hundred discrete transmission line sections
leading to a large set of simultaneous equations for V and I
which are then solved by Gaussian elimination.
The transmission line model employed takes into account the capacitance
profile, mutual inductance, end-effects, and inter-turn capacitance.
The program outputs the base input impedance as a function of frequency,
together with the V/I profile of the coil.

The aim of these two programs is to be able to compute the resonant
frequencies and input impedance to better than 5 percent starting
from the gross physical characteristics of the resonator. While there
are other programs better suited to assisting with practical coil
design issues, the intention here is to clarify understanding of
the resonant mechanism, thus the programs are written for clarity
and precision rather than efficiency.

It would be nice to see this software released to the public domain, but
some further work would be needed first. For example, tlap.c requires
some
attention to the method of simulating boundaries at infinity, and tsim.c
suffers from the lack of a model of ground plane I^2R losses. These and
other defects mean that the above aim has not yet been achieved.

This software would benefit from peer review, and requires validation
against a range of actual coils.  Therefore I would be pleased to hear
from anyone who would like to contribute to a collaborative effort to
finish, validate, and package these two programs.

The software is compiled under gcc and runs on unix workstations.
tlap.c expects an X11 display terminal.
Documentation is latex/dvi/postscript.

Regards,
--
Paul Nicholson,
Manchester, UK.
paul-at-abelian.demon.co.uk
--