To: vortex-l@eskimo.com Subject: Re: [Vo]:DGT or ECAT? Same Process? From: dlrober...@aol.com Date: Tue, 9 Jul 2013 22:38:55 -0400
That is very interesting Dennis. If I understand you correctly, you solve the thermal run away problem by extracting heat fast enough to keep the thermal positive feedback loop gain below unity. That should work provided there is enough energy released per pulse of drive to achieve a high enough COP. Yes, that is the way I look at it. You can get large COP at lower outputs and lower temps. For example I have a small unit with no sparking that has infinite COP but only fractional watts of excess. The behavior that you describe would not depend upon very much gain being augmented by thermal feedback as I suspect that Rossi is relying upon. Do you understand why a spark would be so efficient at producing LENR? You mention local heating as a possible factor, which certainly could cause small hot regions to develop. Is this the key to high gain without meltdown? There must be a thermal path out of the region to take away the heat at the right "speed". I assume that that could be done by adjusting the particle size and "packing", but in my case, the metal host occupies pores within carbon. Once a hot spot is initiated, what prevents the heat from spreading rapidly into the adjacent material and causing a sudden extreme burst of energy? Perhaps the distribution of active hydrogen in the NAE is such that areas capable of spreading the heat only exist in small patches and are easy to extinguish. If this is true, new active regions would need to form in time to take over the process as others die out. Again, I believe the rates have an exponential them. coef. Notice in my case the active regions are isolated via the carbon. So as the heat spreads other regions would not be at as high a temp. and have a much lower heat production rate. The slowly extinguish as the spark moves to other regions. So what functions does the spark perform in a system of this type? Heating of a small region makes a great deal of sense as each spark strikes the surface. Also, do you expect that the spark breaks apart the hydrogen molecules as a second function? I can imagine a rain of protons falling upon the metal due to ionization as another possible piece of the puzzle. The spark just causes very high local temps. I don't really see the spark functioning to ionize the H (my case D and H). I think it is the H already in the lattice that reacts. Has there been evidence of enhanced reaction caused be the magnetic field associated with the currents entering or leaving the metal surfaces? If I recall, DGT speaks of dipole behavior of Ryndberg hydrogen helping out. Can you describe any evidence of this? Yes, it seems that the reaction is almost linear in respect to the B field. (also linear with mass, and expon. in terms of Energy of vacancy formation. (that is why Ag helps Pd system and Cu and Pd ..... helps Ni systems.) I believe that the H occupies or must move through the vacancies. The occupation of H in a vacancy is likely in a controlling pathway. Your bowl shaped targets are quite interesting to consider. Does the bowl tend to spread out the spark contact region? Yes, think of the plasma globe type lights. I have a central electrode (actually W rod held by a Cu tube). It is within a brass sphere holding my material. But the material is only "stuck" to the lower half on the wall. >From what you describe it appears that your reaction is almost entirely a >surface effect. Would you expect a very thin layer of active metal to work in >the same manner? A thin coating layered upon another passive metal might be >helpful in preventing a large scale thermal event. Maybe one of Axils heat >pipes underneath could extract the heat quickly enough to enhance the net >energy density. Yes, one configuration (I have 4) has variable heat conductive >heat pipes. I have to juggle the heat extraction and production. (changes >contact areas) Do you have to worry about the destruction of your active material as the process operates? If I "turn it up" to much my material is destroyed. In one device, I use internal B fields (added Sm 2 Co 17 powder) and it will demagnetize. Are you planning to demonstrate one of your devices at the conference? At NI Week (Booth 922). It will be just a "golly gee" type of demo not a science "prove it" demo. Small in the few watt range. I hope to be upstaged by Defkalion. Dave -----Original Message----- From: DJ Cravens <djcrav...@hotmail.com> To: vortex-l <vortex-l@eskimo.com> Sent: Tue, Jul 9, 2013 9:29 pm Subject: RE: [Vo]:DGT or ECAT? Same Process? My take on their process is that the control and the sparks are related to the positive heat coef. of the reaction and the rate at which the heat is extracted. My best empirical model shows an almost exponential increase in max power output with temperature (due to vacancy production). A few very hot regions can produce a large fraction of the output. My reoccurring problem is to balance the temperature of the reaction species with the rate at which I remove the heat. You remove too much heat and the reaction sites cool down and the reaction slows. Most people seem to be looking at the global average temperature of the bulk and not the temperatures of local areas. By sparking to your sample you can have very high local temperatures and thus higher local reaction rates, IF your material is such that its resistivity increases with temperature. Notice this is the case for most metals. Since the sparks target the paths with greatest conductivity, the sparks are to new regions with lower temperatures and lower resistance. i.e. you hit new regions. I believe that they are basically sparking to a flat area within a cylinder. I prefer to use a spark into a bowl shaped target. You just simply make sure that your heat flow out of the system is large enough to stop any runaway reactions. (you are also saved by the 4th power law) For my system, it is a balancing act between heat production and heat transfer out of the system. I do that by both having a variable heat conductive path (variable contact areas by turning- think variable air caps) for rough tuning and then changing the spark rate (I use a strobe circuit). Dennis To: vortex-l@eskimo.com From: dlrober...@aol.com Date: Tue, 9 Jul 2013 18:39:06 -0400 Subject: [Vo]:DGT or ECAT? Same Process? Whenever I read about the DGT device I get the impression that it behaves much differently than the ECAT. The main difference I focus upon so far is the method of control. We have discussed the ECAT thermal positive feedback control on many occasions and have developed models that appear to explain its operation. The same is not yet true for the DGT beast. Thermal control such as that used by Rossi seems to have difficulty achieving a stable COP of 6 for the basic device excluding electrical power generation and feedback. Of course it is expected that one will be able to use the fed back electrical power to drive the device one day and achieve a net COP of infinity. This should become possible fairly soon and Rossi appears to be working hard to arrive at a reasonable design. DGT suggests that they potentially can already obtain a large COP, but I have questions about the design since little has been demonstrated in public. My reservations can easily be disposed of by additional information and I anxiously await that time. The spark plug like ignition system of the DGT animal bears little resemblance to the thermal operation of Rossi's ECAT. I have the suspicion that there is something important to be learned by the fact that these various devices both function. How can that be? What is it about the DGT design that appears to efficiently use the spark induced reactions while maintaining excellent control? We certainly are not interested in hot fusion products which tend to be associated with high voltages such as spark discharges. If acceleration due to high voltage is present then why does this not occur? Does DGT balance the spark magnitude carefully enough to avoid this fate while achieving adequate LENR activity? I want to learn from the DGT device as well as the ECAT. There appears to be an understanding among most of us that some form of NAE is present which allows LENR to proceed, but what form does it take? Is it the same for both designs? What does the spark of DGT offer that heat alone seems to neglect in the ECAT? It seems as if the ECAT would love to thermally run away without much provocation while the DGT device does not seem to exhibit that behavior. Perhaps DGT has done a good job of hiding this problem, but they offer information that suggests that this is not happening with their design. I find the description that the DGT design can be turned on and off rapidly to potentially find applications that are diverse such as transportation, the gold standard of mine as evidence. If thermal run away were a major issue, then the rapid control might not be so easy to demonstrate. >From the information that I have gleaned, both systems appear to offer >excellent energy density and good power output. This is extremely important >for future applications. It will be interesting to witness the race between >these two horses in the near future. Of course, others might enter the fray >soon and we all will benefit it that occurs. I realize that I have touched upon a multitude of interesting issues in this post and I hope that some of our esteemed members can add important information to the discussion. And if the answers to some of my questions appear, then that would be fantastic. Dave