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Re: Racing Spark Prediction

Original poster: "Gerry  Reynolds" <gerryreynolds@xxxxxxxxxxxxx>

Thankyou Paul and Bob.  This helps some.

Gerry R.

Original poster: Paul Nicholson <paul@xxxxxxxxxxxxxxxxxxx>
Gerry wrote:
> Im wondering if there is a third component to the voltage
> profile...
> For a 1000 turn coil probably 1000 little traveling waves each
> starting from a different turn of the coil if you get my meaning
> here.
That's fine.  These are all contained within the calculated self-
resonance of the coil, and your description in term of travelling
waves initiated on a turn by turn basis is a valid way to look
at the thing.   After all, our models start by setting up the
equations for a single turn or section, whatever, of the coil
using a general label say 'x' to indicate some arbitrary place
on the coil, and then we say - right, apply those equations to
every section of the coil, simultaneously, so we end up with a
whole stack of equations, identical but for a different value
of 'x' in each.  That's how we build up, row by row, the matrix
system mentioned above.
> The current flowing by the traveling waves creates a magnetic
> field that propagates at the speed of light to all other turns
> in a direct path instead of following the wire path.
Yes, and ditto the voltage and electric field.  We can forget
the speed of light, seeing as the coils are so small compared
with a wavelength, you can just say that the coupling is
instantaneous which makes the arithmetic a lot easier and only
loses a miniscule bit of accuracy.
> Does this paradigm seem reasonable???
Yes, although it doesn't add "a third component to the voltage
profile".  Superposition works here - model the response as if
each turn is excited (somehow) in isolation and add it all up
to get the familiar 'total' voltage.
Each section of the coil can be thought of as being a simple
harmonic oscillator in its own right, each coupled to every
other by the E and H mechanisms.  The combined motion of the
them all is what we see as the V/I distributions.  This is
much like a vibrating beam or string, but those are simpler
because each 'oscillator' is coupled only to its immediate
neighbours.  In the resonating coil, you have long range
coupling between oscillators which makes the behaviour much
richer - dispersive propagation, complex characteristic
impedance, etc.
Paul Nicholson
Manchester, UK.