Some Comparison Results - Updated

We are trying to figure out if this previously damaged wire is giving us any real excess heat, or if we are seeing an artifact of pressure changes and other characteristics of the cell.  Towards that end, we have executed a few tests over the last few days to try to compare the effect of cell temperature, pressure, and cooling and reheating.

First, on the evening of the 26th of Nov, we turned on the Celani wire to 48 W to give us an immediate reference.  It settled to about 0.5 W

Then we turned on the NiCr wire to heat the cell while keeping the voltage and current through the Celani wire constant.  This resulted in a P_xs that started at 0.75 to 1 avg and ended up bouncing around 0.25 in the morning.  A slight increase over the roughly 0 to .25 we saw with just the Celani wire heating immediately previously.

Then we briefly turned off the Celani Wire and let it cool before turning it back on in order to try to estimate the working temperature of the wire at his higher cell temperature range.  Results on that to be shared later.  I am a little bit behind in my analysis.

Next, we turned off the Celani wire and adjusted the power on the NiCr wire to be exactly the same as what the Celani wire had been.  This passive heating of the active wire actually seemed to show a slightly higher P_xs in the 1 watt range.  This could be attributable to the variation in surface temperatures.

Finally, we decided to re-pressurize and replicate the exact conditions that we saw a week ago when we started the long rise run.  On the evening of Nov 20th, that run started out at 4.5 Bar and 43 Watts and a curiously low P_xs of -2.5 or so.  To explore the range just a bit more we pressurized the cell up to 6 bar when at temp and we are allowing it to slowly decline because of the known leak.

After we powered it up to 43 watts we saw the P_xs approach -6 at 6 bar.  As the pressure dropped, we saw the P_xs rise.  Once it hits 4.5 Bar we will see if it matches the previous data.  If it does, then we have pretty good evidence that we are not generating any more energy int he wire than we were a week ago, which is presumably nothing.

We do think we have a handle on why we are reading values that are so far below our calibration curve.

When we look at the T_mica and T_GlassOut vs Pressure at 110W and just today at 48 W, we see some very explanatory curves.

This first graph we have published before.  We took points from each calibration right around 110 watts and plotted the temperature achieved versus the cell pressure at that time.  It is interesting to note that the H/Ar line crosses the He line at about 4.7 Bar.  This lead us to do the next 3 graphs.

First we asked what it would look like at points near 48 Watts.  Same basic shape, but the line for H/Ar crosses the He line at 3.7 Bar. That is close to the range of pressure where our P_xs crossed zero last week. 

But we are measuring based on the T_GlassOut, so we plotted those, too.  First at 110W range and next at the 48W range.

In the 48 W range that we were at during the slow rise last week, we see some enlightening relationships.  First, we see the cross between the Helium line and the H/Ar line crosses, again, at 3.7 bar - where our long rise last week reached zero.  That makes sense because we are using data from the Helium run with this wire as our calibration data.  If we imagine our pressure starting out at 4.5 bar for this run and moving slowly to the left on the red line, we can see that we would measure a temperature below the blue line, then approach unity, and keep rising up to a max and then hold steady above the blue line from that point on.  That is almost exactly what we saw during our run.  (Time to go plot that T_glass_out vs Pressure over this graph, I guess, since most of it was at 43 or 48 watts.)

What this makes me wonder is how this curve looks up to 8 Bar where Celani was working?  And then, how would that pressure related curve reflect in the Stephen Boltzman calculations that Celani was using?  Should be easy enough to estimate.  Anybody up for it?  

Update:

Malachi and I made a couple more graphs, but I though they fit best in this blog article rather than in an entirely new one. 

Here is one of the graphs we made above with the data from various runs we have done in the last week.  I gotta admit, it was not as easy to understand as I thought it would be.  There are a number of variables, still, since these were just sections of data that we happened to have near these conditions.  I think this calls for a controlled run aimed at comparing to these curves.  

Notice, though, the blue squiggly line from the long, slow rise we saw last week ends with a couple jumps up?  That is quite intriguing.  I didn't expect that.  All the data was in the 75%H2/24%Ar blend.

And this is the above graph normalized somewhat by dividing the T_GlassOut rise by the input power.  This does favor the lower power levels somewhat, but does help make things more comparable, overall.

If you can't really come to any insights fro the above 2 graphs, I don't blame you.  If you can, please share.

Below is a graph Celani made of one of his successful runs including a loading phase and a running phase.

Can the phenomenon we are seeing with the pressure effect explain some of the excess power in the above graph?  If so, how much?  It is interesting that his leak is roughly the same rate as ours, too.  

Wouldn't this whole thing be easier with a calorimeter?