Re: E-Tesla 6.11 strange prediction

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

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Matt,

E-Tesla6 does a lot of rounding and scale fitting to improve accuracy with
lower grid sizes.  In other words, it "jiggles" the data a bit to give the
best results.  However, that causes some little discontinuities in tests
like you are doing here.  If the program did not do this, there would be
far greater error.  I ran a diagnostic plot just to check for basic
dimensions and such and all seemed fine:

http://hot-streamer-dot-com/temp/MattD1.gif

The only way around this is to uses a higher grid size (longer time...) or
take the data you have and draw a smoother curve through it.  The rough
error here is about 4% which is a bit higher than I would expect.  It
really is also possible that there is some "real" discontinuity too, but I
sort of doubt it here since the data seems so well behaved otherwise.  I
ran your data that you gave with a 200 grid size and got the following:

C=22.23451 F=287737.94

With a 400 grid size (it is raining here too :-)):

C=22.30953  F=287253.72

It would be especially interesting to compare this data to your actual
measurements!

Cheers,

	Terry


At 04:26 PM 5/19/2001 -0400, you wrote: 
>Hi Terry, All! 
>While waiting for the rain to stop (4 days now) I tried doing some "what-ifs" 
>with the E-Tesla 6.11 program in which I raised and lowered the primary coil, 
>keeping all else the same. There is a discontinuity at 19.75" that I cannot 
>explain. Is this a critical point in reality, or is it a computational 
>anomaly caused by the finite math of the CPU? 
>        It will take a few days after the rain stops for the Lab (garage) 
>floor to dry out before I can take measurements. 
>Primary Cap.Calc Fres Calc 
>in.         pF                     kHz 
>16.50 22.23451 287.737 
>17.50 22.32667 287.143 
>18.50 22.43735 286.434 
>19.50 22.55733 285.669 
>19.70 22.55771 285.669 
>19.75 22.55710 285.669 
>19.80 24.25782 275.477 
>19.90 24.25782 275.477 
>20.00 24.25782 275.477 
>20.50 24.29766 275.251 
>21.50 24.66628 273.186 
>22.50 24.79134 272.496 
>23.50 24.96715 271.535 
>24.50 25.26754 269.916 
>25.50 25.60428 268.136 
>26.50 25.96334 266.275 
>Here is the other data from one run: 
>E-TESLA  V6.11C  November 21, 2000 
>  
>Grid Size = 200.000000 
>Scale Multiplier = 1.000000 
>Terminated Coil 
>Ceiling Distance = 96.000000 
>Wall Distance = 48.000000 
>Primary Height (Inner Turn) = 16.500000 
>Primary Inner Diameter = 6.375000 
>Primary Outer Diameter = 24.375000 
>Primary Height (Outer Turn) = 16.500000 
>Strike Rail Height = 25.000000 
>Strike Rail Diameter = 30.000000 
>Secondary Base Height = 25.000000 
>Secondary Diameter = 4.280000 
>Secondary Length = 21.160000 
>Secondary Inductance (mH) = 13.760000 
>Terminal-1 Height (center) = 51.799999 
>Terminal-1 Cord Diameter = 3.250000 
>Terminal-1 C-C Diameter (toroid only)= 8.000000 
>Terminal-2 Height (center) = 55.400002 
>Terminal-2 Cord Diameter = 4.250000 
>Terminal-2 C-C Diameter (toroid only)= 13.750000 
>Top Voltage = 360.000000 
>
>Thanks, 
>Matt D.
>