100KVDC, oil is a resistor

Without checking the video, that doesn't sound surprising. Lots of common oils contain detergents that absorb water (and keep it dispersed rather than settling out).

Good dielectric oil is probably treated with heat and vacuum, or something like that.

Tim

-- Seven Transistor Labs, LLC Electrical Engineering Consultation and Contract Design Website:

That aerial oil transfer is kind of cool.

Huh, I don't understand the Russian, But it looks like he's mostly just playing with a dielectric (oil) in a non-uniform E-field.

Any conduction looks like break down, or maybe a surface thing.

George H.

On a sunny day (Wed, 17 May 2017 22:38:15 -0700 (PDT)) it happened Bill Beaty wrote in :

:-)

We certainly ran ours through a vacuum filter on its way back from the outside tank (assumed, probably correctly, to be filthy and damp) to the guts of the machine (big honking Marx, it made one heck of a bang.) How I do not miss working on its oily guts (it never really dripped dry - fortunately, there was only one major overhaul inside the tank while I worked there.) We'd also run the filter in circulation sometimes.

We had a lot of super-spiffy water, too. Mostly used as the dielectric in huge stainless-steel coaxial lines. But as far as I recall that was all in the other lab that had a nice warm inside tank for the oil (but we still went through a bunch of drierite keeping moisture from getting in via the tank vent.)

electro static? Looks like the Oil sticks to (-) electrons?

Cheers

Sure (maybe) a dielectric in a E-field gradient feels a force. The filaments of oil 'shooting' out of the glass is weird. But maybe the oil is forming around an already existing air breakdown channel. (?)

George H.

Need to try it in hard vacuum. But first need 300KVDC supply!

Probably it's just caused by oil conductivity. Field gradients only produce fluid humps, while actual fluid pumping requires some milliwatts and some electric current. He could collect those oil streams in a Faraday Cup, to measure their average current.

Gigohms at kilovolts gives microamps of leakage: a current which easily could be transporting charged droplets (moving a microcoulomb of charged oil per second.) To prevent the droplet-jets, the little streams would have to block the microamps by presenting a far higher resistance than mere gigohms.

That's only 25,000 DieHards, how many hundred amps did you need? :-)

it's some crazy russian dude with hundereds(?) of kilovolts making the oil move with electrostatic forces (and the stream carries the charge on its surface)

It looked like a bottle of cooking oil.

Yeah I don't know. As Jason says there will be charge on the surface. (Those E-field lines have to terminate somewhere.) So I assume the little oil streams are conducting current also. I'm not sure how you'd tell if it's bulk vs a surface effect.

George H.

If there's a single semiconductor device still operating in this guy's house, I'm quite surprised! Geez, how many times has he "tazed" himself!

(Yeah, I know, somebody managed to video him.)

Jon

As the oil temperature increases it's insulating properties decrease. You get small currents flowing, ua maybe depending upon the surface area and distance. I don't know what oil that is, but diala AX will do this. I've seen strange solutions used to solve this problem. ( Creapage is still a problem in oil too)

Cheers

Is he still alive?

Cheers

OK, I have a friend of a friend who got the high voltage bug. He was doing all sorts of Tesla coil experiments. He used the glass top of his parent's dining room table as the capacitor, and that was great until he broke the glass (high voltage punch-through). Then, he got a dental X-ray machine out of a neighbor's basement. He bought a string of 10 KV rectifiers and made a whole table full of Leyden jars out of gallon jugs. Those, of course, were even thinner than the tabletop glass, so they were exploding from time to time. He was creating arcs that would jump over a foot down in the basement. One time, the arc jumped to the furnace ducts. A light bulb exploded all over his mom, reading in bed upstairs, blew out wiring in the kitchen ceiling, and did "something" at a neighbor's house that had the electric company there all night. Never had the courage to ask the neighbor what caused them to call the electric company.

Jon

On a sunny day (Fri, 19 May 2017 20:16:20 -0400) it happened Martin Riddle wrote in :

Ask Schroeder ?

Measure the nanosieverts with your Fluke 189? Then move some L-shape probes around under the surface?

Or, perhaps drip some aquadag or some fat-soluable dye into a big warm mug of oil, then see if sharp wires from 30KV supply, immersed in the oil, will produce fluid jets and push the dye-plumes around.

Oil isn't that great an insulator when compared to solid dielectrics. The tiniest bit of ion contaminants will start flowing as electrolytic current. I imagine that's why oil-filled HV capacitors have such large "soakage" ef fect, and they self-recharge if not stored with a shorting bar. The charg e that flowed from plates into the oil, flows back to the plates again.

I had a giant box of 9V alkalines, all drawn down to 8V or so. Years later I discovered that an hour on a bench supply at 50mA constant current will charge up a half-dead 9V battery to 10V. Instead of 1800VDC worth, I coulda had 2.3KV

es around under the surface?

g of oil, then see if sharp wires from 30KV supply, immersed in the oil, wi ll produce fluid jets and push the dye-plumes around.

e tiniest bit of ion contaminants will start flowing as electrolytic curren t. I imagine that's why oil-filled HV capacitors have such large "soakage" effect, and they self-recharge if not stored with a shorting bar. The cha rge that flowed from plates into the oil, flows back to the plates again.

Hmm, I guess I just don't see how some small number of ions in the oil can lead to the bulk streaming.

If we knew the current and had some guess at the electric field, we could estimate the surface charge. (From curvature of surface) And compare that to the current.

George H.