EU V1.3 dual cells LIVE RUNs thread [UPDATE#2 - What a difference a day makes]
Mathieu is absolutely foaming at the mouth to hit the script for the first part of the live run ... should we let him?
Here was his worrisome state a few moments ago...
UPDATE#1 - Cells turned on
Cells are go in France.
UPDATE#2 - What a difference a day makes
Well, pretty much 24 hours after we loaded the wires passively, the wire is de-loaded with just the application of passive heat and a vacuum.
The plan therefore is to re-load, taking onboard the experience of the first loading where we saw it was not really vital to cycle it. Also we will use the US teams experience and go strait for 35-40W in the passive wire. After loading, we will complete the next segment of what was going to be the first run, that of powering the active wire. We will not do it is two hour steps like before (which was to allow the US team to catch up) but 1 hour steps and start from 10W.
Interestingly, Mathieu noticed just before he turned the power off, the wires had become darker. See here:
Also, Nicolas pointed out something that is interesting to note. the resistance plots of the wires in both cells. First the A and B NiCr passive heating wires.
Pretty much the same...
... the Celani wires however acted very differently.
Comments
An alternative approach to using high hydrogen pressure or powerful external heating appears to be making the gas (pre-heated?) actively and continuously come in contact with the heated active element(s).
This could be achieved by a constant gas flow directed toward the active element as described in Piantelli's patent (and as Rossi appeared to do in his earlier experiments, according to expert analysis of the available photographic evidence), through gas pressure pulses, or with well controlled gas ionization through electrical sparks as Defkalion does (the process was broadly described in their ICCF17/NIWeek presentations).
It looks that H2 has to "move around" and heating it directly promotes this process but might not be enough depending on how the cell and the active elements are made.
This is of course in the speculation realm, but I'm relatively confident it might be one of the keys for excess heat generation.
After some thinking and daydreaming, I feel your speculation that the temperature of H2 is more important than that of wire makes sense.
If you check Rossi's rig of the Ecat-HT, the heating wires are placed around the core, so they heat the gas more than the powder. Same (I guess) for DGT plus they ionize the gas with a spark plug making it even more potent.
Intuitively also, it appears that heating the gas (or make a plasma out of it) would diffuse it better and deeper into the wire, while heating the wire would expel the gas out. Indirect heating works well, so another experiment would be to move the heater element out to the surface instead on the mica and fill the gas at very high pressure. This will need another rig (and we can throw away the glass finally).
The active wire in US Cell A (under 45W of passive heating vs 40W of the EU cell) is nearing 13 Ohm in a heated state. This means that once power will be removed, it will end up having a lower resistance (or in other words, better loading) than the active wire in EU Cell A. So what initially looked like a defective wire, is probably going to be best one tested so far, and mainly because of the higher temperatures attempted there.
The active wire in US Cell A has a 250 mW power applied to obtain stable resistance measurements, and this further increases its resistance compared to the active wire EU Cell A, which has currently ~75 mW applied. However I wonder if it's also having a role in long term hydrogen loading.
I agree with you fully. The reversible drop/increase in R is a very important result indeed. It also shows, in addition to the conclusion you stated, that the R drop is not due to a chemical reaction changing the Celani wire. At least, the difference in speed during re-loading puts a big question mark on it being a chemical reaction. (Few days vs few minutes)
R/R0 is now back at its previous value. Good news is that the US wire is also getting close to 13 ohm.
I thinks its wise to not to attempt higher temperatures or powering the wire directly at this stage and try the run with H2 and see what happens. Later on there will be ample time to mess with higher and higher powers.
Probably high power passive heating, with some way to keep hydrogen moving around inside the cell is the way to go. However I wonder if too much direct IR from a highly heated passive wire might damage the active wire.
Borosilicate glass however has about a 300°C safe temperature limit, although we're still far from it.
a 1994 video of Focardi speaking about Nickel - Hidrogen studies he was conducting with other experimenters. Interesting part begin at 8:00. After a while, it says that they found that Nickel will adsorb an important amount of H after 400C. This behaviour was not found in literature.
So yes, temperature is definetely a good point to investigate.
(maybe in steel glass cell? )
So H2 loading/deloadi ng is almost totally reversible in both ways. I think this is a very important confirmation for Celani's work (some skeptics speculated that the resistance drop was due to surface microstructure sintering).
I wonder if making the wire absorb more by increasing temperature would increase its H2 storage capacity permanently like it seemingly did with the first loading.
I don't think the outer layers are conductive. The exact composition is proprietary to Celani but probably oxides of various other metals. They're applied as a coating, looks like about 20 um thick in the micrograph. There's probably some reaction with the CuNi at the interface that creates nano structures of some kind. Or maybe the coating itself provides the NAE. Do we know? SEM images recently posted show some craters in the coating of the wire after treating with acetone. But these could be chemical in origin and the text doesn't say whether the treated wire was heated in the presence of hydrogen.
quantumheat.org/.../360-02.jpg
From quantumheat.org/.../...
Yeah, I saw that. THe figure I used is toward the high range of their data ( 74 ppm vs 80 ppm). So the change is still off by about an order of magnitude.
Getting back to the surface defects, the wire in cell B isn't hydrogen-reduce d but if there's no free oxygen or other contaminants from outgassing, could the walls of micro-cracks stay clean enough to close up and conduct on heating?
isabellenhuette.de/.../...
(see page 3)
It appears that resistance (under standard conditions ie unloaded) decreases slightly in the temperature range used by this experiment, so maybe it's not an anomalous effect after all.
Yes, got that.
The actual delta R was -0.141 ohm
Constantan is apparently available in a range including negative thermal resistance coefficients. Surprisingly, the Wagner data sheet for ISOTAN44 tinyurl.com/pnzcom4 doesn't give this info. One other reference shows a nominal alpha for Constantan of -0.000074 and calculating back from the delta T of 173C it predicts only -.0127 ohm resistance change. So yes, something else has probably happened.
Regarding surface microstructures , are you thinking of cracks (per Ed Storms) that close up on heating and become conductive again? The annealing temp of Constantan is around 800 C I think.
You wrote:
Resistance changed by less than 1%, but that was a negative change. If it wasn't for the microstructures on the wire surface likely closing with temperature, this would be the behavior of a negative temperature coefficient material.
@MFMP: I don't think there's much benefit in keeping the cell loading at this temperature for 36 more hours. The loading rate after being extremely fast during the first minutes of loading, has noticeably slowed down and is not likely to bring wire resistance significantly below 14 Ohm. I would either try increasing heater power to the level of US Cell A or begin now the second part of step 7 which was supposed to be peformed immediately after testing the cell under vacuum with the passive wire.
Germanium is a metalloid that does and not many others do. I think some oxides might as well.
The non linear response in resistance as it's increasing is of interest too.
It looks like it also very quickly hit a plateau at about 14.08 Ohm. I wonder if increasing passive heating further (45W like with US Cell A for example) will help it decreasing or if resistance will start increasing as if a loading limit has been reached.
Check the experiment blog.
We took out the check valve as it was causing a wobble on the temps and reducing the vacuum capability.
We pumped down cell, recharged with H2.
We then set about putting power directly to 35W - but a limit on the script was causing wild fluctuations... A little bit of tweaking to the control software and the power in to the passive wire is now fixed at 35W...
Did you see how fast the resistance changed???
@MFMP-EU: it appears there are problems with both the live feed and data.
I think it is a combination of the Constantan properties combined with the nano-structures /grain boundaries in the Celani wire closing up as they heat.
The resistance change is small over this wide temperature range.
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