Dr. Case's Experiment: Run 2 5MAY98
Scott R. Little, EarthTech International, Inc.
*** This test was conducted with a substitute catalyst *** (This experiment employed apparatus described here. )
In Run 2. I made modifications to our setup so that it would more closely approximate the setup used by Dr. Case.
I filled the chamber only about 1/3 full of catalyst so that only the bottom thermocouple was covered. The middle and top thermocouples were thus exposed directly to the hydrogen gas in the upper part of the chamber. I also moved the heaters down to the very bottom of the chamber, putting two of them around the lower flange and packing the other two down as close to the bottom as possible.
At the start of the run, I pumped on the chamber for about 40 minutes and then filled it with 50 psi of H2 (as indicated).
About 55 minutes into the run I applied 40 watts of power to the heaters and, during the next hour, gradually stepped that down to 20 watts. At this input power level the catalyst temp, Tbtm, stabilized at about 180° C.
About 3.2 hours into the run, I vented, evacuated, and refilled the chamber with H2 gas at 50 psi (as indicated).
About 4.75 hours into the run I vented, evacuated, and filled the chamber with D2 gas at 50 psi (as indicated). Surprisingly, there was no significant change in the temperature of the catalyst.
About 6.2 hours into the run, I vented, evacuated, and filled the chamber with H2 gas again (as indicated).
Note the peculiar behavior of the Ttop and Tmid probes after this last filling. Previously they had been running very close to each other. However, they are now widely separated with Tmid about 30° hotter than Ttop...and Ttop noticeably cooler than before!!! I am at a loss to explain this behavior...especially the spontaneous recovery than occurred about 25 minutes later (marked by a "?"). One thing that might be involved is the fluffy-lumpy behavior of this catalyst powder. During the venting, evacuation, and refilling procedure it is likely that the catalyst is blown around in the chamber by the flowing gas. Maybe the catalyst was so arranged after the 4th filling that the middle thermocouple was covered with it...but that doesn't explain the drop in the Ttop trace. I doubt if this peculiarity was due to an electrical signal problem but that possibility cannot be eliminated.
Note that the Tbtm trace showed no significant disturbance during this anomaly. Also note that the Pout and Pin traces show a near-perfect power balance throughout the ~5.5 hour period when the heater power was maintained at 20 watts. There is clearly no sign of excess heat from this experiment.
About 6.7 hours into the run, someone turned on the A/C in the lab where this experiment is housed (who could blame him at 32° C). I turned it off within 10 minutes but not before the Pout trace was significantly affected (note the little bipolar excursion). This calorimeter system handles slowly varying ambient temperatures well but it cannot react fast enough to handle the rapid excursions created by the air conditioner.
The minor dips in room temperature that coincide with the refilling operations are a result of cool air admitted to the lab when I come in from the front office to perform the refilling procedure.
This run also showed no sign of the effects we are seeking. Hopefully the proper catalyst will arrive tomorrow. Stay tuned for further developments.
Comments are most welcome.