Can't help thinking optical thermometry would be preferable since it's impervious to heat damage... assuming the steel currently used for chambers is entirely incidental to the reaction, a transparent ceramic would would allow direct observation - if not for the whole chamber, then at least a via a small window...
For example Perlucor is stable up to 1,600 c and 3-4x stronger than glass: https://www.ceramtec.com/perlucor/ You'd think it'd be practical to fabricate a whole test chamber from this stuff.. On Mon, Feb 29, 2016 at 10:12 PM, Jed Rothwell <[email protected]> wrote: > H LV <[email protected]> wrote: > > Notice the delayed rise in T4 at the beginning of the experiment. The > > rise in T4 after power is turned off might just be the delayed >> dissipation of heat from inside to the outside. >> > > I do not think so. Look closely as the power is being reduced, at around > time 14:00, shortly before "Power off." (About 7 minutes before.) T4 > suddenly pops up, from 110°C up to around 120°C. > > Maybe that is just noise, but if it is real, it does not look like delayed > dissipation to me. > > Unless the configuration of the cell is changed, I do not see how the > dissipation could increase suddenly like that. By "changed" I mean for > example, suppose the MgO insulation is wrapped around and attached with > adhesive tape. Suppose you loosen the tape. The outside temperature might > change suddenly. I doubt anyone would make such changes to the cell during > a test. > > If there were heat left in the cell that had to be dissipated after the > power is turned off, I suppose the T4 curve would continue rising at a > steady pace for a while, then it would drop off. It would not have leveled > off after 13:20. It seems the temperature inside the cell continued in a > stable condition if we can believe that either T1 or T2 was working > correctly. So there was no large increase in the internal temperature. > > Granted there was a sudden increase in temperature in T1 and T2. It > happens at time 14:20. I just drew some lines on the graph, and I think > that T1 and T2 go up and reach a peak about 6 minutes before T4 suddenly > increased. T1 continues for 26 minutes at the higher temperature. > > I would not expect T4 to pop up like that in response to the increase > shown by T1 and T2. I would expect T4 to gradually rise in response to that > increase. Perhaps it might continue after T1 peaks, but it would be a > continual, gradual rise. That kind of slow rise is what T4 does after the > initial jump, followed by a gradual decay. > > - Jed > >
