From: "Terrell W. Fritz"
Date: Sun, 13 Oct 2002 12:32:46 -0600
Subject: Re: [TSSP] Top Voltage
Hi Paul,
The ceiling is pretty close. Should I put grounded foil on it?? But I think
that raises the fields even more to further go in the wrong direction... See
the Tesla list posts today from Jim and Antonio about corona breakout voltages
too.
Cheers,
Terry
At 06:53 PM 10/13/2002 +0100, you wrote:
>Terry,
>
>> I raised the medium sphere to 7.25 inches from the top edge
>> of the toroid to the center of the medum sphere.
>
>> http://hot-streamer.com/temp/OLTC10-12-12.gif
>> http://hot-streamer.com/temp/OLTC10-12-12.CSV
>
>We get a nice clean set of data from the coil in this position,
>perhaps we can leave the other positions and spheres alone for
>now and focus on just this one setup. It seems to demonstrate
>around a factor of 2 discrepancy, so it's a good one to study.
>
>I took away the ceiling and walls altogether to get a prediction
>of 120kV for breakout. That compares with 101kV predicted with
>walls and ceiling present, and a measured value of 204 kV.
>
>So the ceiling makes a difference, but much more is needed.
>
>When modeling this setup at Vfire=270, I get a base current
>peaking at just under 2 amps. When looking at OLTC10-12-12.CSV
>it appears the base current peaks at 2.32, so something is
>a good 15% out here. Perhaps I need to revise my Q factors
>because I'm still modeling with the lossy coil, Q=40 or
>thereabouts. Unfortunately, correcting that will push down the
>predicted Vfire values even further - another 15% in the
>wrong direction (:
>
>Not only that, but I haven't factored in your altitude yet,
>which would further reduce the predicted thresholds, so that's
>another step in the wrong direction.
>
>I think we'll have to wait until we get some toroid breakout
>measurements to see if they are way high too.
>
>Meanwhile I'm going to have a close look at the model for
>the above case and compare it with those nice tcma outputs
>that you sent.
>--
>Paul Nicholson,
>--
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.