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Re: pure water capacitor?



Tesla List wrote:

> Original Poster: "Jan Florian Wagner" <jwagner-at-cc.hut.fi>
>
> Hi,
>
> >I've been trying to do some research regarding design issues, when I came
> >across a list of dielectrics for some materials for use in capacitors.  The
> >dielectric constant for pure water is around 85 with an infinite breakdown
> >voltage!
>
> It sounds wonderful... but...
>
> Bad thing is you'll never get even close to "pure" dielectric water -
> first of all the autoprotolysis (OH- and H3O+ from 2*H20) will make the
> water always slightly conductive no matter what, then also the two
> (insulated or not) electrodes placed in the water will make the cap a
> lovely electrolysis and/or O2 and H2 generation chamber that will explode
> right in your hands if there's any chance of corona forming around one
> electrode and igniting the highly explosive H2+O2 gas mixture. :o(
>
> If current is low, 30mA or so, then maybe you could use some method of
> pumping out the gases and feed in new water...
>
> But, the water cap won't work, because the polarized molecules are free to
> flow from one electrode to the other along the electric field. They don't
> remain in place like they should.
>
> Not to mention impurities that come either from the electrodes themselves,
> or the container material, or the surrounding air leaking in. The
> impurities alter the dielectric and conducting properties of the water.
>
> Only thing that you could try to do is a ice capacitor - distill water and
> freeze it in a vacuum, then use the ice as dielectric. Moving molecules
> shouldn't be a problem then, neither water conduction, nor gas generation.
> But you'd have to keep the thing cooled down somehow, and try to ban all
> corona around the electrodes. :(
> Just a thought.
>
> --
> *************************************************
>  Jan Florian Wagner

I just want to clarify one thing i read a lot of archives from tesla list and
time to
time i see reference to electrolysis but electrolysis is possible only with DC
with
AC as low as 60 cycles the molecules of gas have no time to migrate and
recombine as soon as they are produce.

Luc Benard