For the EU cell, I slightly changed the way the calibrations are being done, taking into account what we have learnt from Ryan's team during their first few weeks.
First, I am using a constantan wire kindly provided by Nicolas, it has the same metallic composition as the active ones, it is the same size (0.2mm diam. 1m long), but it is coated with an (unknown yet) oxide layer, insulating and preventing hydrogen uptake. This is very important, Francesco Celani told us, even bare constantan wire absorbs small quantities of hydrogen.
After a few tests, the drop in resistivity in this specific constantan wire was only 2.4% compared to the 18%+ we had with the active wire ran by the US lab. Moreover, this drop occurred at very low temperature, where the active wire dropped at 170°C. To me, it looks pretty convincing that no hydrogen was loaded into the wire. Maybe I am wrong. Let me know your thoughts.
So the cell calibrations will be performed in the same conditions as with the active wire (75%H2 + 25%Ar @3.5, 2 and 1 bar because it will leak through overtime) with a range of power that is close to the operating powers (28W, 38, 43, 47, 52, 58, 63, 69, 73, 78, 83, 88, 92 and 100W, the last one is not necessary...). After one hour of temperature stabilisation we sample one point that will be used to plot the polynomial cuve used as a baseline for calculation of excess energy. The choice of which Tc to use is boggling since T_in is influenced by the gas mixture. We tend to use T_out but it is highly influenced by ambient temperature...
T_well is the last option, but it is broken on Cell#2.
I did another one this afternoon using the same gas mixture at 1 bar pressure for each power step.
This gives a set of 3 curves for a gas mixture. 1 for constant pressure. It is also worthwhile to use 50-50 mixture because the hydrogen is the most inclined to leak through the cell. All this curves will help to interpolate and anticipate experimentally the future behaviour of the cell.
Then we have to consider low pressure case. So I use 0.5b of pure H2, I also do 1b of pure H2 because I might try this way at the end. However the cell will leak...air inside, hence it is also necessary to do a 50-50:This email address is being protected from spambots. You need JavaScript enabled to view it. ; and acquiring data during that time too to detect endothermic/exothermic reactions.
The question of the leakage is related to the fact that we are doing replication as much close to what Francesco was doing in NI week and ICCF. We also want to run the cell "until it dies".
But that is not sufficient for the calibrations, as we have to do calibrations for third parties with activated wire (as a reminder, we plan on shipping the cell to universities). Calibrations runs with He under 3.5b, 2, 1b and 0.5b will be helpful for future users.
When this will be the necessary, she can uses Francesco's technique of heating the wire under vacuum that can help releasing H for the wire's lattice. It can also be lethal for the wire too if too much power is injected in (especially in vacuum because of the absence of convection). 1.9A is the maximum current that Francesco recommends.
The use of oil-free vacuum pump is mandatory because of possible back-streaming of oil inside the cell reaching the wire.
Finally, we have the loading phase that require to use of 3b of pure H2 then rise temperature of absorption: ~170°C.
Then the gaz mixture is introduced and the power is immediately turned on to reach 48W operating power.
I have already done the first batch of calibrations with the mixture, taking advantage of the programmed calibration script, I did ran the cell 24/7. I will make my best to reach operational run as soon as I am done with all these.
Comments
I believe this approach would easier and cheaper than flow calorimetry...
By using two active and two inactive cells, one could rule out other factors if the inactive cells show the same internal and external temperatures and the active cells, at the same time, show significantly higher temperatures in accordance with Celani's colorimetric formulation.
So I guess the result is normal. Now the question comes , whether the R/Ro of 0.8 for Celani wire has anything to do with H2 adsorption and how to show it conclusively.
That was my idea and while it might help sort out anomalies it's not without possible side effects itself. Since putting gas under pressure into the cell is going to have a delta effect on the temperature. I still think it's worth a try though.
I didn't get much feedback about the question of the location of the thermocouple on the glass (is it on the top of the glass? How's it attached to the glass? Is it possible to move it to the bottom of the glass or to turn the entire cell upside down just to get some more information?
And while I recognize that the supply of wire is limited, the more of it you can get and use at one time, the better your signal to noise ratio will be.
You have done an excellent demonstration of why spot temperature measurements are rarely a good substitute for formal calorimetry in LENR/CF experiments.
I respectfully suggest that these two ideas (doing calorimetry and increasing the quantity of active elements in the system) should be the thrust of future efforts.
The idea of having a much larger same pressure reservoir was noted and may be tried at some point.
@Pekka
This has been identified as being annoying internally and a fix is proposed that would mean that there would be a toggle to switch between UT and local time.
(By the way: it would be more convenient if hugnetview would operate on UT time instead of local time.)
Is the thickness of "nanostructured " skin of Celani's wire known (and accordingly, its % in the cross-section of the wire)? If the "skin" is very thin, it should not be able to affect wire resistance in any significant manner, unless something very unusual is happening in this layer.
A while ago some other reader suggested in the comments a simple way to stabilize the pressure. I haven't seen any follow-up on that idea, so assumed it was overlooked by the MFMP team. Might be a good idea to have a second look at it now.
The idea was to stabilize the gaz pressure in the cell by keeping the cell permanently connected to a large-volume "buffer" gas tank (both kept at the same pressure, obviously). That would drastically increase the total pressurized volume, so any leak you might have in the cell would affect the pressure much less.
An extremely good fit was obtained with my time parameter beginning at the power transistion for t=0 seconds. The fit envolved using three exponentials. The first and second are related by a factor of 2. I assumed distortion due to quadratic nonlinearity for this choice. The third exponential is most likely due to a delay of some kind and is of short duration. The curve fit equation is as follows:
T_GlassOut=114.7+52.01*(1-e^-.003532*t)+4.91*e^-.0071*t+3.39*e^-.034*t.
Values rounded to save space.
50% - 50% mix is an explosive composition.
The temperature ignition of H2 and Air mixed is around 500°C. (See wikipedia) The heating wire might come easily above 500°C. If iginition occurs then a lot of chemical energy released in a short time (explosion).
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