Re: Alternate toroid shapes

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

Original poster: Bert Pool <bert.tx-at-prodigy-dot-net> 

If you examine the drawings and photos of the Wardenclyff tower, this is 
exactly the design Tesla used.  The bottom of the sphere curves inward and 
up, forming the bottom half of a toroid.  This is best illustrated in his 
patent drawing of the Wardenclyff magnifier.  What is really interesting is 
that the curve of the toroidal part is not spherical, but forms the 
beginning of a spiral, the curve appears to match phi, the same curve ratio 
of the nautilus shell and other similar designs found throughout nature.
Bert


At 06:32 PM 12/14/03 -0700, you wrote:
>Original poster: Dave Leddon <dave-at-leddon-dot-com>
>Back in the sixties I purchased a three foot diameter spun aluminum oblate 
>from F. B. Lee (anybody remember his contributions to the Amateur 
>Scientist) who claimed that this shape, which resembles a hemisphere on 
>top of a toroid, was the best shape for a Van de Graff generator because 
>it would accumulate maximum charge while minimizing break down on the 
>supporting column.  I often wondered if this shape would represent any 
>sort of improvement over the classical toroid.
>
>Dave
>
>
>At 10:53 AM 12/14/03 -0700, you wrote:
>>Original poster: Paul Nicholson <paul-at-abelian.demon.co.uk>
>>John Richardson wrote:
>>
>> > Has anyone done any experimentation into toroid topload shapes
>> > other than the typical round designs that all use?
>>
>>AFAIK little has been done.
>>
>>Toploads have two important parameters:
>>
>>a) the amount of charge they hold per unit volt, a.k.a the
>>    capacitance.
>>b) the voltage at which they begin to issue streamers.
>>
>>Toroids tend to have a larger capacitance for a given breakout
>>voltage, compared with sphere terminals.  And they seem to be
>>preferred for streamer formation, perhaps because of this.
>>
>>But who is to say there isn't a better shape?   It could be
>>that the best streamer formation comes from toploads with modest
>>breakout threshold plus large charge storage.
>>
>>You could approximate your proposed tear drop cross section with
>>a sphere or toroid with a disc shaped skirt, so that from a
>>distance it looks a bit like Saturn.   You would have to tell
>>us whether it behaves any differently to a toroid plus breakout
>>point.
>>
>>Plenty to do here for theorist and experimenter.  See recent posts
>>by Antonio for the relevant modelling programs.
>>--
>>Paul Nicholson,
>>Manchester, UK
>>--