Experiment Steps (updated-again)
We have chenged the conditions to attempt to load the wire with Hydrogen once again. We loaded the cell with Hydrogen and set the power to achieve T_Mica of 170C. We are heating the cell with the nichrome wire. We watched for a couple hours and the resistance of the wire did not change much compared to the first loading cycle. So, we upped the power to try to go to 200C.
We do not have a good baseline for this point of operation. The closest is calibration run 7, which was H2@ 3.5 bar, but heating with the Isotan wire instead of the Celani Wire. The next best data we have is Run 1 in Helium, but that was heating with the Celani wire.
This is where we sit on the graph of the Calibration 7 compared to the readings as of 4pm US Central Time. 
The Ambient is trending downward, but relatively slightly. The Pressure in the cell is currently 4.7 bar as compared to 4.5 bar during this point in the calibration. That should, according to out experience, result in a lower T_mica than the baseline.
Here is another setting from a calibration run we did before Cal1 where the cell had Nichrome on both power channels.
Opinions?
Comments
Or maybe letting the reactor "rest" in current conditions for some time *is* the plan?
Don't get me wrong: it's not that I'm impatient to see results, I'm just asking because watching events unfold in real time is quite intriguing - and personally I wouldn't want to miss them or needlessly wait for them (a concentration/p roductivity killer, by the way :) ). I think other followers would agree with this too.
I really hope that running the wire quite alot above the 160 -170 deg C triggering point hasnt heated the middle of the wire to cause it to sinter. I suppose if there is not much indication of excess heat then you can always pull it out and run it under that nice SEM you have to see whats going on.
Two reasons, Safety, with the main valve off if the regulator fails – no problem. This setup also keeps a positive gas pressure in the lines - this reduces the likelihood of gas contamination and gives a running indication of any leaks in the hydrogen gas line up to the isolation valve.
Point noted
More importantly. Vertical orientation significantly reduces convective losses to the bottom flange.
You have more or less described our Generation 2 reactor - I like the vertical bit though, can drop on insulators and flow calorimetry modules and they would sit there under gravity!
This is important when you are trying to show the source of the anomalous heating.
@Ecco – thank you – I stand corrected
A better (future) solution would be to use a single ended glass tube with a glass to metal flange seal at the other end. Mount the unit vertically with all connections through the base flange. This setup enables remounting without disturbing any connections. Mount the Celani wire tightly wound (minimum gap between turns) at the top of the tube with thermal baffles below. Wind the heater wire around the outside of the quartz tube and thermally insulate the complete length of tube.
1) Have you tried to calibrate the IR thermometer to correct for the quarts tube? I could imagine a simple IR calibration setup with a few turns of wire on mika + thermocouple and an identical quarts tube sliding in/our, could be in the air at normal pressure (no sealed flanges).
2) Is there any difference in measuring IR from the regular (smooth) wire and Celani's (due to different emissivity)?
3) Do you plan to use an IR camera to continuosly monitor/record video of the wire during active runs? It is possible that if you have any excess-heat, the reaction will be in localized bursts clearly visible on IR video.
What would happen if all of the IR were absorbed between the source and the monitor? Can we believe this type of measurement?
However, the R/R0 after cool down was still way under 0.9 so the wire is still partially loaded.
Celani did report that he got good Excess with passive heating.
Whilst Celani wires have triggered between 250 and 350, we are being told that recent ones are triggering at above 350.
From the video - you can see that a hunch about localised heat variation is panning out - there are areas that are starting to be above the expected lower triggering temperatures, but we are still wary of this.
The problem with so much variation in the cell would be mitigated by a tube that thermalised all IR and then effectively averaged the temperature through the mass of the glass.
We will let the thing run to gather data and then crank up the power in the NiChrome and see if we can push more of the Celani wire into potentially revealing the effect.
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