Hi Horace, Thanks for the information concerning your model. It helps to visualize the time delay effects that have been difficult to get a handle upon. I notice that the model has only one dimensional variable which is this case is X, but we probably get a fairly good idea about the temperature distribution since the latest ECAT cores are planar instead of cylindrical in form factor.
With this new input, I think most of us can see that the gradient varies greatly from the water entry region(X=12) toward the heat generation point which is X=0 in the model. The time domain effects must be taken into consideration as we attempt to analyze the heat transfer phenomenon. This observation should explain why the power can appear to rapidly increase without implying that the core has to become intensely hot. Anyone interested in understanding why the core does not have to heat up directly in proportion to the instantaneous output power should review the graphs that Horace has constructed. Dave -----Original Message----- From: Horace Heffner <hheff...@mtaonline.net> To: vortex-l <vortex-l@eskimo.com> Sent: Sat, Nov 26, 2011 10:19 pm Subject: Re: [Vo]:Large Temperature Increase of Core Not Required for 6 to 1 Output Delta On Nov 26, 2011, at 7:11 AM, David Roberson wrote: It has been suggested that it is not possible to obtain the rapid increase in output power measured for the Rossi ECATs. The reason stated is that the core would have to have its temperature multiplied by a factor of 6 or so to deliver the needed power. This belief is based upon a misunderstanding of the heat equation and its solutions. You can find a reference to this information in Wikipedia at http://en.wikipedia.org/wiki/Heat_equation. This is a partial differential equation that is not very easy to understand but ties the distribution of heat within a system to time. One look at this complexity and you can see why it is confusing. It is correct to assume that the temperature gradient immediately feeding the ECAT water storage must be increased by the 6 to 1(or whatever you need) ratio. I doubt that anyone would argue that point, but that does not imply that this gradient must exist all the way to the ECAT core modules. Maybe some of the Vortex members are thinking about the stead state temperature distribution. In that case, the temperature gradient would become smoother and follow a curve based upon the heat flow through the area encountered along its flow path. In the steady state solution we would expect the core temperature to in fact rise by the ratio of the output powers as has been argued since it is the source of all of the heat energy. The ECAT core temperature is not required to operate under steady state conditions until a very long period of time has elapsed. This long period is not being allowed by definition due to the rapid power change observations argued against. Consider this thought experiment. The cores of one ECAT are heated within 5 minutes to a high temperature by the electrical heating element leading to the generation of LENR heat. The cores are now at a temperature that allows the total output to be 9 kW where they continue to supply energy into the heat sink. The water initially knows nothing of this power since a significant delay exists as the heat makes it way toward the water. The gradient of temperature facing the water is zero until the leading edge of the heat wave reaches that position in space. Since the gradient is zero, no power is being delivered to the water. Next, time elapses and the heat begins to flow into the water and increase its temperature. A gradient is now established to allow the heat flow and this gradient rapidly increases as the power delivered to the water increases. The gradient began at zero and will increase as needed to allow the heat flow required. There is no reason why this gradient change is restricted to a value as low as 6 to 1, and I would expect it to be far larger until the system stabilizes. Horace Heffner has been generating a finite element model of the heat flow within his assumed ECAT scam device and will be able to demonstrate this effect to anyone who does not understand the mechanisms involved. I recall a time domain chart he published to vortex that shows his expected gradient of temperatures along the heat sink. This graph should be used as reference. Horace, please take a small amount of your time to explain the effect that I refer to since you have the finite element model that reveals the solution to the partial differential equation. A demonstration is worth a million words in this case. Dave Hi Dave, I am unable to contribute much to discussion at this time. I haven't been reading vortex, so my remarks may not be relevant. I found this post by scanning for my name. I'll comment briefly. Yes, finite element analysis (FEA) in general typically consists of solving partial differential equations with boundary conditions, by discrete approximation means In the case of dynamic thermal FEA, the equation being solved, in some form, is the heat equation you reference. In the case of the E-cat, the heat equation applies to any heat conducting layers between the reactor and resistance heaters and the water. The boundary conditions essentially amount to the thermal (electrical) power input on the hot side, and the temperature gradient near the solid/water surface. The higher the near-water-surface gradient, the greater the heat transfer power to the water, ignoring the effects of steam bubbles etc. The following graph demonstrates these principles: http://www.mtaonline.net/%7Ehheffner/Graph6S.png The power in on the left side (X=0) matches the Pin for the 6 Oct Rossie experiment. The thermal gradient at the water end (X=15) is represented by the slope of the temperature curves at for the various times, which is shown with magnification. You can see the effect of the water side gradient in the Pout curve (blue) in this graph: http://www.mtaonline.net/%7Ehheffner/Graph2S.png The power out corresponds in time to the changing of the thermal gradient through time. The following graph shows the temperature curve family in the case where there is perfect insulation inserted at X=15, between the thermal conducting slab and the water: http://www.mtaonline.net/~hheffner/Graph7Sx.png Thermal output power at any given time can be highly variable, and delayed in time from the generation of the heat in the reactor. Except that dynamic FEA is likely necessary to determine maximum operating temperature of the reactor, given the dynamics of the power input, the thermal gradient is of limited interest concerning total energy production. For this reason I have consistently advocated well calibrated dual method calorimetry that determines a complete energy balance for each test, and have suggested various inexpensive methods of achieving that, such as ice calorimetry, one barrel and two barrel steam condensation, combined flow condensation, etc. http://www.mail-archive.com/vortex-l@eskimo.com/msg50611.html http://www.mail-archive.com/vortex-l@eskimo.com/msg48555.html http://www.mail-archive.com/vortex-l@eskimo.com/msg51875.html I think the format of spread sheet I used for the Rossi data, e.g.: http://www.mtaonline.net/%7Ehheffner/Rossi6Oct2011noBias.pdf is useful for both calibration runs and controls, as well as live runs. Its focus is on consistent power, energy and COP data. To see what professional level dual calorimetry actually looks like check out: http://www.earthtech.org/experiments/ICCF14_MOAC.pdf Curiously, Rossi had everything needed for fairly good calorimetry at the 1 MW test. He had two large plastic water reservoirs. Little extra was needed to sparge/condense the primary steam/water into the reservoirs, and then to use the air-water condensers in a secondary circuit to cool the reservoirs and measure the thermal output. Just some extra copper pipe and fittings, and perhaps an extra water meter, were all that was required. Best regards, Horace Heffner http://www.mtaonline.net/~hheffner/
