Having a switching control of the heater bias is not at all going to fix a reactor that is unstable once it reaches a critical temperature. Such a reactor will continue to rise in temperature with NO input at all (pulse width =0). Such devices as have been shown today have essentially a fixed thermal resistance to some temperature sink near ambient. The only thermal change that will quench such an out of control reaction is to lower the thermal resistance to the low temperature sink. One good way to do this is with having convection cooling and having a fan blow a variable amount of cool air over the reactor. There is no need for water because it is difficult to control the amount of cooling you get to such a high temperature device. Air can be really linear in thermal cooling. In fact, you could use the air flow as a temperature regulator in combination with the heater control.
Also, note that Rossi does use a thermocouple control for his hotCats - it is seen in his lab photographs. He monitors the core temperature and puts that into a PID controller. Such a controller can behave in ON/OFF mode to completely turn OFF the bias heat when the temperature rises above a preset limit. There can also be alarms put in that controller that would turn on a fan to lower the thermal resistance to ambient. All with his hotCat hardware today. And Rossi does use pulse width control of the AC power he is supplying. On Tue, Feb 10, 2015 at 1:40 PM, David Roberson <dlrober...@aol.com> wrote: > Jones, > > When I first began modeling the ECAT several years ago I used exactly the > concept that you are suggesting. It did in fact appear to yield a COP of 6 > or in that vicinity with careful adjustment of the PWM drive waveform. I > used the duty cycle that Rossi had revealed within his blog entries before > the recent shut down of important data. I even applied the amount of power > that he spelled out. > > That was how it was left to await further proof until the Swiss > experiment. During that experiment I saw a behavior that did not match > the negative resistance region requirements from my earlier models. I > could never arrive at a COP of 6 without having one of those to boost the > output power. At the time I was a bit puzzled by the device and the > apparent lack of that important condition. I soon realized that either > Rossi intentionally gave them a low fuel charge that guaranteed stability > for their test or that he had produced a new design of the type 2 category. > > Had the scientists carefully increased the input drive power is small > steps I could have easily determined whether or not a type 2 system was now > in existence. Unfortunately this was not done so I must conclude with > caution that a type 1 is what was tested. In that case the thermal > feedback is limited so that a negative resistance region is not present at > any operating temperature. The COP will then be limited to less than 4 > under ideal conditions which is lower than most of us would like to see in > the long term. > > Perhaps Rossi realized that even a COP of 3 would prove to the world that > he had some magic. The latest replications are not limited in the same way > as Rossi did and the extra insulation as well as amount of fuel can be set > as desired. This is just what we needed. It appears that we are now > observing the negative resistance region of operation and the thermal run > away that can easily tag along. I have my fingers crossed that someone > will find the magic solution that leads to a type 2 system which will be > highly desired since the COP can be very large and stable in that mode of > operation. > > This is an exciting time for all of us and what we have been waiting for. > It does mean that many devices are going to melt down before the process is > tamed. I hope that proper precautions are taken to ensure that no one is > injured by the multitude of explosions that might well be seen in the near > future. How much energy can be released during the worst case melt down > event is not obvious so there may be substantial risk to the brave guys > working within the labs. So far Rossi is still among us so the danger may > not be too much greater than already witnessed by the MFMP crew. > > Dave > > > > -----Original Message----- > From: Jones Beene <jone...@pacbell.net> > To: vortex-l <vortex-l@eskimo.com> > Sent: Tue, Feb 10, 2015 1:11 pm > Subject: RE: [Vo]:Explosion May Be Out of Control LENR > > *From:* David Roberson > Actually the characteristic curves suggest that the input power acts > like a bias that stands behind the incremental behavior. If that bias is > quickly removed then there should exist a point of operation that is > located ahead of the dangerous region. Unless some strong memory exists, I > can imagine that the process would reverse as we all hope. > > Dave, > Given what you say above – what about the possibility of a higher level > of control simply by use of pulsed power (at very low duty)? > For instance, if we know from prior experiment that 100 watts of DC will > eventually lead to large gain but at the risk of thermal runaway, and we > also know that quenching begins almost immediately with removal of power > (unless > the system has already progressed to instability) – then it would seem > that low duty pulsing with the same net power will provide better control > against a runaway. (that is the premise but I have not data to back it). > In effect, as an alternative to 100 watts DC, it would be possible to > design and construct a pulsed power supply that will provide something > like 2000 watt pulses at 5% duty. The net power in is the same, but 95% > of the time there is no power. The frequency can be long but the idea is > to alternate short sharp pulses with long delays. > Is there any reason in your model to suggest that this approach is valid? > Jones > >
