Phenomenon observed by Tesla

[TinselKoala]

I think HeairBear has something there. At these extreme pressures and flows, the conduction electrons in the copper are indeed somewhat like an incompressible fluid, and we know what happens when you give a sudden blow to an incompressible fluid. You get, among other things, "shock" waves (pun intended!!) that can be very physically disruptive.

Also, it is my impression that the event is a combination of EX plosion and IM plosion. The metal implodes from Lorenz pinch forces at the same time becoming superheated thru Joule heating, which vaporizes the insulation (sometimes) and the metal, which turns to plasma if the current is high enough...which explodes from overpressures and shock waves...
It's a much more complex system than it appears at first glance.

(I don't like to get into my own pet weird theories in public, but the doubled inductors in my system have to do with my ideas that, at these tensions, there does seem to me to be a positive analog to the negative electron current. That is, like Franklin, I believe there might be two electrical fluids somehow involved in an opposing circulation. Hence the inductor on each line.)

In public I will say that I am going for a somewhat underdamped ring down of the capacitor during the arc discharge and while the wire is experiencing whatever it feels. So I want the electron flux to experience an inductor between the cap and the wire sample no matter which way it's sloshing.

By far the most interesting phenomenon, to me, is when the tiny, extremely fragile tube made up of the enamel insulation coating a #36 or #40 bit of magnet wire, would REMAIN BEHIND apparently intact, or in several longish bits, even though the copper had completely vaporized or was ejected in globules like in the trace I posted above.
Explain that one, if you can!! It is much easier to replicate this effect than to get the wire segmentation effect of Graneau et al. I was able to do it a handful of times, out of the couple hundred shots I did.

[Grumpy]

Maybe the copper was in a vapor state when it went through the insulation - sort of like high pressure steam.  The exit hole would be very small - possibly to small to see with your eye.

Have ever seen the "buckling" effect? - this is where the wire is bunched up by the discharge.

You can also get the wire to creep along in the direction of the discharge - it take about 1000 discharges to become noticeable and the energy must be low enough to not explode the wire.

[TinselKoala]

"vapor"
You mean you don't think the copper was blasted into the Seventh Dimension, bypassing the enamel altogether?


Yes, that's pretty much the conclusion I came to, as well. At the time I didn't have access to a proper microscope to examine the tubular shells up close for pinholes or other penetrations. I figured the tubes might also be split lengthwise and re-curled so the split was invisible or even resealed. Of course the samples are long gone, but now I do have access to the appropriate microscopes.

"buckling"
No, never, and this was one of the things I was specifically looking for. You will note that I used (and pictured in the diagram) long loops of wire rather than a straight line between clips (although I did many straightline shots too). This would have supported the Graneau hypothesis of Ampere tension in the wire, I thought. But I wasn't able to see that effect. The only shot I made that supported Graneau's hypothesis was the single one where the wire segmented. I have heard of the effect in railguns and other high-energy pulse systems.

"creep"
No, not in my experience with this apparatus. But I wouldn't have, because most of the conductors were flexible multi-stranded cables, and I was specifically trying to explode the sample wires. But I do know, as above, that it occurs in high-energy pulse power applications, for sure.

[Raui]

TK, your contribution to this discussion is priceless. I am going to experiment with that circuit however instead of using a bonetti machine I will use the high voltage supply I have created using a fully rectified flyback transformer. When the circuit is operating I am not even going to be in the same room as it, I will be behind a brick wall outside only observing via a window which I am going to remove the glass from. One question though, how displeasant are the 'shockwaves' and from how far back can you feel them? Also does the amount of clothing you are wearing effect the strength?

[forest]

TK, your contribution to this discussion is priceless. I am going to experiment with that circuit however instead of using a bonetti machine I will use the high voltage supply I have created using a fully rectified flyback transformer. When the circuit is operating I am not even going to be in the same room as it, I will be behind a brick wall outside only observing via a window which I am going to remove the glass from. One question though, how displeasant are the 'shockwaves' and from how far back can you feel them? Also does the amount of clothing you are wearing effect the strength?

If you perform that experiment, get also a photographic paper enclosed in black envelope and place near the exploding wire. That way you will know if there is any radiation similar to X-Rays.