The attached graph (with my annotations) is from the paper
http://lenr-canr.org/acrobat/EssenHexperiment.pdf It has several interesting points.First, as I've said in previous email, the total power dissipated in the device can be estimated from the slope of the curve and the temperature of the effluent. The power needed to heat the output water goes up linearly with the temperature of the output water, and the power needed to heat the device goes up linearly with the slope of the curve.
There was a claim of "ignition" at about 60C, at which point the device started generating power. In fact, the graph says that can't be right. If the device generated no power before it hit 60 degrees, the temperature would not have gotten to 60 degrees so quickly, because (as stated in the paper) the heater temperature was only adequate to maintain it at 60 degrees with the flow rate used in the experiment. So, the heating curve, instead of looking like a straight line, would look like a capacitor charging curve, and it would have taken much, much longer to reach "ignition".
The steam was claimed to be dry in this experiment. In that case, the output power was something on the order of 10 kW once it started producing steam. But the output power before that point, which we can read from the graph, was about a factor of eight less than that. So, once it hit boiling, the output power must have increased eight fold, very rapidly -- certainly more rapidly than the power had been increasing up to that point. But then, since the effluent temperature did not rise above 101C, the power generation must have stopped its meteoric rise at exactly the core temperature needed to keep the effluent at 101C, no more, no less.
If the device were running open loop, that would be absurd. There *MUST* be a feedback mechanism to keep the temperature almost exactly at boiling.
Complex scenarios regarding the contents of the blue box have been posted to the list, explaining how the feedback must have been done. However, as far as I can tell, these are pure speculation, with no statements from Rossi to back them up. Furthermore, there's no evidence of any feedback wire leading from the effluent temperature sensor, and no statement from Rossi to indicate that such feedback might exist. On the other hand, it seems unlikely that feedback from a sensor in the core would be able to hold the effluent temperature exactly at boiling; feedback must have been derived from the actual effluent temperature.
But there's a much simpler explanation: "Internal feedback", in the form of entrained water droplets, would nail the output temperature of the steam at, or just above, boiling. There's no need to imagine complex feedback circuits, sensitive control electronics, nor any need to postulate a reason why the optimal temperature at which the circuitry held the temperature must be EXACTLY BOILING, rather than, say, 7.5 degrees above boiling. (BTW, if I recall correctly, someone looked up the boiling point that day at Rossi's location and ambient barometric pressure, and it was actually about 101C, not 100C -- so this really was nailed *at* *boiling*.) Furthermore, this avoids the need to believe in the "inflationary" phase during which power generation increases dramatically for a brief period just after the output temperature hits boiling.
I realize I've waved my hands a bit here; it's been a while since I worked this out and I don't have all the data and equations in front of me. If anyone cares, I can go back and get some numbers out of the above cited paper and tighten up the argument a little. I could also plot the temperature rise we'd expect to see if generated power didn't start until 60C (it really does look like a capacitor charging curve). But I think what I've said here should make my reasoning pretty clear.
Finally, there's a much more disturbing issue with the attached graph. The temperature rise in much of the graph is not just above what we'd expect to see if the power generation were fixed -- it's actually LINEAR. From initiation to about 45 degrees it's dead linear; from 60 to 80 degrees it's dead linear. Other segments are look nearly linear.
Now, those linear rise segments could be the result of a coincidence: The generated power just happens to be rising exactly fast enough to keep the effluent temperature rising linearly. That might be a bit surprising, but it's certainly possible. But it could be the result of something else: If the effluent flow rate were zero at the site of the temperature probe, we would see a linear temperature rise. The reason is that the expected non-linearity results from the fact that the power needed to sustain the effluent temperature increases as the effluent temperature increases, because the temperature gradient from input to output increases. If the effluent isn't flowing, however, the temperature rise is limited only by the need to heat the thermal mass of the device, which is fixed.
The "linearity" argument is very far from conclusive, of course, but it's one more thing that bothers me.
Finally, I have just one more comment on the "dry steam" issue. It seems obvious to me, as I've said repeatedly, that the steam wasn't dry. Rossi says it was, and the folks he was working with say it was. You may conclude that they're the authorities, and therefore I'm all wet; that's a fine Appeal to Authority argument (since they won't publish the data on which they base their "dry steam" conclusion it's all you've got). But I, on the other hand, must necessarily accept my own opinion <g>, and must therefore conclude something different: None of these people can be trusted, either because they're not honest, or because they do not know what they're doing. Consequently, as far as I'm concerned, the results of all "private" tests for which we don't have clear, conclusive reports and data, and at which we didn't have competent observers, probably should be ignored. And that includes the subsequent "sub-boiling" run, of course.
********************BTW somewhat similar reasoning applies to the "natural ratios" problem. Rossi said (somewhere) that the isotope ratios which he's seen in the ash and generated copper are not natural. Rossi has sent out one (1) sample to be tested by an independent lab. The ratios found were natural.
Complex explanations have been proposed, ranging from insensitive equipment to bizarre multibody fusion theories. Yet, a very simple explanation covers the result very well: Rossi lies.
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