Thanks Ed, I have concentrated upon the overall picture with my model instead of the microscopic improvements that are no doubt available. You are certainly correct that the thermal contacts could be improved which will interact in different ways with the system. A balance has to be achieved where the thermal run away temperatures, which greatly depend upon what you say, are practical for best ECAT operation. Rossi needs to have solid positive feedback to get high COP, and he needs this to occur at a convenient temperature which performs well with the core materials.
The issue of hot spots is certain to come up during his design meetings and much of that depends upon how the material is bound to the heat sinking and how uniform it is deposited, etc. I suspect the solutions to this type of problem are keeping him busy. There are a number of challenging engineering questions that will arise as he handles the temperature effects associated with the heat exchange process. That team is going to have a busy schedule. Dave -----Original Message----- From: Edmund Storms <stor...@ix.netcom.com> To: vortex-l <vortex-l@eskimo.com> Cc: Edmund Storms <stor...@ix.netcom.com> Sent: Sun, Jun 2, 2013 5:20 pm Subject: Re: [Vo]:Ethics of the E-Cat investigation put into question Dave, I agree. You have described the process very well. The only thing missing from your model is the thermal contact between the source, (Ni) and the sink (the mass of the E-cat). The better the thermal contact, the longer the temperature can remain high while control is maintained and the less external power is required to keep control. In fact, a better design would be to have the heaters inside the container while the Ni was against the outside wall of the apparatus. This way, energy from the Ni could flow directly out and be radiated into space, which would allow for a fast cooling rate of the Ni once the internal power was turned off. Ed Storms On Jun 2, 2013, at 3:10 PM, David Roberson wrote: Eric, Model 1 appears to be more in line with what I suspect is happening except for the explanation of the lack of external heat for control issue. You need to consider that the peak heat power being generated inside the core is only about 2 times greater than the resistor heating required to control it at the turn around point. Rossi has stated this on several occasions and it matches my model. When such a large percentage of the net power at that node is taken away abruptly, a turn around in temperature direction occurs. This is a complicated positive feedback system where a large fraction of the internally generated heat is being absorbed by the thermal mass of the device. Enough external heat is removed to force the core to be "starved". That reverses the temperature path. Once reversed, the positive feedback works in a manner that accelerates the falling core temperature toward room. If you are very good, or lucky, you can reverse the core at just below an optimum point which will allow the temperature to languish there for an extended time before it begins it rapid decent. This is how you achieve a high value of COP. The core has a lot of time during which it puts out large values of heat energy before requiring a refresh drive pulse. The drive remains off for a longer time while the high temperature lingers. Does this help to explain the operation according to my model? Dave -----Original Message----- From: Eric Walker <eric.wal...@gmail.com> To: vortex-l <vortex-l@eskimo.com> Sent: Sun, Jun 2, 2013 4:39 pm Subject: Re: [Vo]:Ethics of the E-Cat investigation put into question On Sun, Jun 2, 2013 at 1:22 PM, David Roberson <dlrober...@aol.com> wrote: The resistive heating requirement is to be able to reverse the temperature excursion at the proper time by removing the extra input. Constant heat input will result in the destruction of the device when useful output power is generated. Dave, I don't disagree with this assessment. But there's a subtlety that the original question is getting at. I don't know how to express the idea with much accuracy, but consider two different models: There is near-uniform heating in the charge. Temperature above a certain point kicks off the reaction. Once going, the reaction itself feeds energy back the into bulk of the charge, where it has been generated, and the reaction becomes self-sustaining. There is non-uniform heating in the charge. Heat flows from hot spots to surrounding areas. The heat that dissipates from hot spots can either be (a) sufficient to kick off the reaction elsewhere or (b) insufficient, in which case it is just dissipated. There is a threshold temperature below which you get (b) and above which you get (a). It seems like a mixture of gasoline or a load of coal that has been ignited is generates heat somewhat uniformly and follows model (1). It seems that model (1), if applied to the E-Cat, would make the resistance heaters superfluous, however. So I take it that we are forced into model (2). To someone approaching things without further context, it's not clear why model (1) would not apply, and that would raise questions about the resistance heaters. Further, I think we have to assume that the heating transients in model (2) are quite high, since there is the possibility of runaway. These are the subtleties I'm getting at. It seems that the requirement for resistance heaters places constraints that can be used to infer useful information about what is going on. Eric
