On Sat, 28 Nov 2015 07:39:56 -0800, Larry Jaques
wrote:

On Sat, 28 Nov 2015 05:45:09 -0800 (PST), Christopher Tidy
wrote:

Hi Larry,

Are you thinking Jacob's Ladder/spark gap? If so, I'd think the
discharges would melt the acrylic tubing in short order.

No. I'm thinking of machine which resembles a Van de Graaff generator. There would be a rounded aluminium terminal on the top. Like this:
https://sharepoint.umich.edu/lsa/phy...or_5A50.30.JPG

Not a clue. But how would you insulate the motor from the charge in
the first place?

The parts of the pump which contact the liquid are entirely plastic (PVDF).

Are you sure? I'll bet the seal is against the metal motor shaft.
Plastic wears too quickly. Still, that would give you half an inch of
plastic to insulate _how_ many kV? Seems iffy at best.


This is what set me thinking about the idea of a Van de Graaff with pumped oil again (I first thought of the concept with bubbles around 2001).

Wild concept.

I've tried to follow the answers you've received regarding oil and
charge, and I'm not certain you're getting correct information.

Dielectrics, permittivity and so on is an aspect of electricity about
which I'm pretty vague, but my recollection is that a
high-permittivity material, like the mineral oil used in oil-filled
capacitors, polarizes easily with a low charge on the opposing plates,
and I would think that equates to a high potential to store an
electrical charge. (or maybe it's irrelevant, because polarization is
not the same thing as storing a charge)

But, as I said, I've always been a little vague about this, being more
interested in the results in a capacitor than in the electric charge
within the dielectric. For example, although there is a high degree of
electrical polarization within the oil, I believe that the net charge
is zero. What that implies for the ability of oil to*store* a charge
is where I'm vague about it.

Sorry if this just confuses the picture. But I think you need to dig
deeper to get the answer you're looking for.

--
Ed Huntress