Axil-- Reactivity is the instantaneous ratio of neutron production to neutron loses (reactions with any isotope in the reactor plus loss from the reactor boundary). A critical reactor is balanced and does not change power. In a water reactor, if you change the water temperature of the coolant, the average neutron energy and the thermal neutron Uup-235 fission cross section increases, increasing fissions, heat and coolant water temperature. As the coolant heats up the reactivity goes down and the power is reduced. The negative temperature coefficient of reactivity is the parameter that accounts for this effect. Reactor design requires good dynamics and control design to reflect time constants etc in the changes of reactivity associated with anything that can change the reactivity. The key in a reactor is to maintain the conditions so that the reactor cannot remain critical considering fast neutrons alone. That is call super criticality and leads to the rapid release of energy and destruction of the reactor as in a nuclear criticality accident.
Bob ----- Original Message ----- From: Axil Axil To: vortex-l Sent: Monday, March 03, 2014 7:54 AM Subject: Re: [Vo]:"Christopher H. Cooper" Positive coefficient of reactivity can never be positive...should read... The coefficient of reactivity can never be positive. On Mon, Mar 3, 2014 at 10:52 AM, Axil Axil <[email protected]> wrote: On Mon, Mar 3, 2014 at 10:06 AM, Bob Cook <[email protected]> wrote: Axil-- Fission reactors with water cooling generally have a negative temperature feedback and are much safer than metal coolant reactors with positive temperature feedback. However, metal cooled reactors have been designed and worked ok. With good design even a positive temperature feedback may work. In a uranium reactor, U238 provides the negative temperature control through Doppler broadening. http://www.safetyinengineering.com/FileUploads/Nuclear%20reactor%20stability%20and%20controllability_1314016641_2.pdf Light water absorbs more neutrons then heavy water and sodium hardly absorbs any neutrons (fast ones) at all. Designing a fission reactor requires a lot of experience and education. Positive coefficient of reactivity can never be positive. That is inviting a possibility of super criticality. A reactor that can go super critical cannot be licensed. In a QM system things happen so fast it would be harder to control than in a fission reactor. The key for control may be to limit the size of the QM system that reacts at any time, or increase the response time of the initiator--may the on-off pulse of the magnetic field in the case of the Pd and Ni systems. The DGT LENR reactor is only supercritical when the spark is arcing. But when the spark is off, that reactor returns to sub criticality. DGT tossed Rossi out of their deal because his reactor can go super critical. DGT designed their home grown reactor to be inherently safe through sub criticality just like all fission reactors. Bob ----- Original Message ----- From: Axil Axil To: vortex-l Sent: Sunday, March 02, 2014 12:04 PM Subject: Re: [Vo]:"Christopher H. Cooper" What is the course of an open ender positive feedback loop without limit. An eventual explosion. Nothing lasts forever in a positive feedback loop. There is always a limit to everything. On Sun, Mar 2, 2014 at 3:00 PM, David Roberson <[email protected]> wrote: Interesting. But how does the net field become large unless some mechanism coordinates the destruction of the balls? Many random direction vectors yields near zero sums. Dave -----Original Message----- From: Axil Axil <[email protected]> To: vortex-l <[email protected]> Sent: Sun, Mar 2, 2014 2:55 pm Subject: Re: [Vo]:"Christopher H. Cooper" Yes, there is a load of fun in this sort of speculation. One possibility is that micro sized magnetic balls as described by DGT that start small and grow to huge power until they explode could produce a varying magnetic field that would induce a current through changing magnetic flux.. On Sun, Mar 2, 2014 at 2:46 PM, David Roberson <[email protected]> wrote: That brings back fond memories. He does say e.m.f. which makes me wonder how he performed that measurement. I would anticipate that he must use at least two probes to come to that conclusion and his active material hopefully does not short out the voltage. Another possibility is that he measured a large magnetic field which he assumes must be as a result of DC current flowing. Since DC current or AC for that matter requires a loop voltage in order to flow, it makes sense to believe that an e.m.f. is present. Actually, an e.m.f. should be present in that case and what Rossi states below about an expert observing it falls into line. I find myself wondering if there are other good ways to achieve very high strength magnetic fields without currents flowing. Permanent magnets offer a clue. I am guessing here and attempting to decode Rossi speak at the same time. That has its hazards! :-) Dave -----Original Message----- From: Axil Axil <[email protected]> To: vortex-l <[email protected]> Sent: Sun, Mar 2, 2014 2:25 pm Subject: Re: [Vo]:"Christopher H. Cooper" Andrea Rossi > December 30th, 2012 at 3:01 PM > http://www.journal-of-nuclear-physics.com/?p=771&cpage=4#comment-514345 Dear Bernie Koppenhofer: You are touching a very important point: during these very days, and also during the more recent tests, we are working on this issue. I think we will be able to produce directly e.m.f. , but much work has to be done. Actually, we already produced direct e.m.f. with the reactors at high temperature, and we measured it with the very precise measurement instrumentation introduced by the third party expert, but we are not ready for an industrial production, while we are at a high level of industrialization for the production of heat and, at this point , also of high temperature steam, which is the gate to the Carnot Cycle. Thank you for your good comment. Warm Regards, A.R. On Sun, Mar 2, 2014 at 2:04 PM, Axil Axil <[email protected]> wrote: I believe that heat is not the only product of the LENR reaction. It may not even the most important sink for LENR power generation. I believe that electron production is a major magnification of over unity power generation. Rossi indicated that there was an unknown source of current production in his reactor and he was looking into how this could happen. I know that the PAPP engine produced current out of whole cloth. The design of the engine depended on it. Here is my take on where these electrons are coming from. When the magnetic field strength gets strong enough, mesons are condensed out of the vacuum. The final decay products of mesons are electrons. On Sun, Mar 2, 2014 at 1:34 PM, David Roberson <[email protected]> wrote: I also find it amazing that DGT seems to overlook the implications of their discovery. It reminds me of not seeing the forest through the trees. Since Rossi made an earlier claim that he might be able to generate electricity directly by some obscure discovery, I suspect that he realized the importance of the large magnetic fields residing within his device. So far he has kept this type of information private, carefully leaking out the news of some non specific discovery. Rossi knows when to release findings that might assist competitors. Dave -----Original Message----- From: Axil Axil <[email protected]> To: vortex-l <[email protected]> Sent: Sun, Mar 2, 2014 1:23 pm Subject: Re: [Vo]:"Christopher H. Cooper" Like you, any one of us can only do so much of what is required. To come up with an all inclusive theory, we must trust the word and the work done by others. I must admit that I trust DGT. So far, their experimental observation about magnetic field strength has no impact on the theory (HEMI) that they put forward. They have no theroritical based interest in misleading us to advance their theory base on Dr. Kims work. Like us, DGT is simply amazed at the magnetic nature of their experimental find but have not connected it to HEMI in any way. This is hard to understand. On the part of DGT, there is no self interest in tossing an almost unbelievable finding into their finding and in fact this finding undercuts HEMI. In fact such a finding is a major distraction. They really need to do a major rethink of their experimental position on HEMI and BEC as per Dr. Kim. On Sun, Mar 2, 2014 at 1:03 PM, Edmund Storms <[email protected]> wrote: On Mar 2, 2014, at 10:47 AM, Axil Axil wrote: > These Nanoplasmonic experiments with uranium can be done inexpensively, why can't Ed replicate these experiments? Because I have only two hands and no financial support. If you want this replicated, I suggest you hire someone to do this. Ed Storms
