Re: Spheres vs Toroids

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Original poster: "Dr. Resonance" <resonance-at-jvlnet-dot-com> 


You will need to deduct approx 10% of this value when the toroid is placed
atop a secondary coil.

Dr. Resonance

Resonance Research Corporation
E11870 Shadylane Rd.
Baraboo   WI   53913
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Sunday, November 02, 2003 1:40 PM
Subject: Re: Spheres vs Toroids


 > Original poster: "Antonio Carlos M. de Queiroz" <acmq-at-compuland-dot-com.br>
 >
 > Hi:
 >
 > I have just finished a routine that calculates exact capacitances
 > of toroids in free space. The routine uses that series with
 > Legendre functions, that is not after all so difficult to evaluate
 > with precision. The values that I am obtaining, however, are a bit
 > different from the ones that I see in the document prepared by
 > Gary L. Johnson.
 > The formula looks the same, but I am evaluating the functions in a
 > different way, using elliptic integrals, that should be almost
 > exact.
 >
 >  >From the paper:
 > Major diameter  Minor diameter  C         My C
 > 90 cm           30 cm          40.46 pF   40.5648 pF
 > 60 cm           20 cm          26.97 pF   27.0432 pF
 > 30 cm           10 cm          13.49 pF   13.5216 pF
 > 56 cm           16 cm          24.55 pF   24.6005 pF
 > 52 cm           12 cm          22.02 pF   22.0615 pF
 > 48 cm            8 cm          19.28 pF   19.3223 pF
 > 44 cm            4 cm          16.00 pF   16.0522 pF
 > 42 cm            2 cm          13.72 pF   13.7969 pF
 > 41 cm            1 cm          12.00 pF   12.1214 pF
 > 40.5 cm          0.5 cm        10.62 pF   10.8164 pF
 > 40.2 cm          0.2 cm         9.09 pF    9.47161 pF
 >
 > There is also a table in the documentation of the program Mandk,
 > but that table appears to use an approximate formula, the same
 > listed in Gary's paper.
 >
 >  >From the example in the Fantc program:
 > Major diameter  Minor diameter    C            My C
 > 50 cm           10 cm             20.73804 pF  20.7282 pF
 >
 > Of course, most of the difference is insignificant for practical
 > purposes, but I want the calculations correct. Maybe the difference
 > is just e0, that I used as 8.85e-12. Only 3 digits are significant
 > in the calculations.
 >
 > The calculation was implemented in the Inca program:
 > http://www.coe.ufrj.br/~acmq/programs
 >
 > Antonio Carlos M. de Queiroz
 >
 >
 >