Re: Calculating Capacitance of solid disk

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

Original poster: "Barton B. Anderson by way of Terry Fritz <teslalist-at-qwest-dot-net>" <classictesla-at-netzero-dot-com>

Hi Dan,

This is a nice function of Fantc. It can perform analysis of object 
capacitance for toroids, spheres, spheroids, discs, and cylinders (up to 10 
each of wanted). In this case, I simply computed the 4" disk capacitance. 
Here's the output at a detail 3 setting.

Computing ..... please wait
System or Object Capacitance: 140.08 pF
Run CompleteTime elapsed: 2.1 secs

To run an objects capacitance, input the dimensions. For your inquiry, my 
inputs were:
disc inside diam. = 0
disc outside diam. = 4
disc height = 0

Then, check the "Disc" checkbox as the system component (only one needed), 
and press the "Run Capacitance Analysis" button.
http://www.classictesla-dot-com/fantc/fantc.html

Take care,
Bart

Tesla list wrote:

>Original poster: "Mccauley, Daniel H by way of Terry Fritz 
><teslalist-at-qwest-dot-net>" <daniel.h.mccauley-at-lmco-dot-com>
>
>
>Instead of a toroid, I'm going to use an aluminum disk top plate which I'll
>lathe to have nice radius outside edge.
>
>Anyone know how to calculate the capacitance of a disk like this?  I would
>think it would be approximately close to
>the standard toroid capacitance formula.
>
>I know I could measure it directly using another coil, but I'll be designing
>and winding my secondary before I machine this
>disk so I want to get a good approximation of the disk.  The dimensions will
>roughly be about 4" diameter and 0.5" in height.
>
>Thanks
>
>The Captain
>
>
>
>