Andrew,
Remember that this is the behavior of a model. Also, if operation is allowed
at a very elevated temperature, the core might fail in a short time frame which
appears to be what happened in the first of the three tests that were conducted.
I suspect that fluid flow might be able to rescue the over heating core, but it
is not clear that this will be fast enough to prevent damage to it. Internal
hot spots might make operation in this region fleeting.
I do believe that initial heating can start the device on its way to the
condition you are considering but it will eventually reach a point where it can
no longer be controlled by drive waveform modification. Hit it with serious
cooling and if lucky, you may be able to keep it from self destructing long
enough to demonstrate the SSM mode to your satisfaction.
Dave
-----Original Message-----
From: Andrew <andrew...@att.net>
To: vortex-l <vortex-l@eskimo.com>
Sent: Sat, May 25, 2013 1:43 pm
Subject: Re: [Vo]: ECAT Drive PWM Issues
Dave,
You therefore answer in the affirmative - i.e. it looks possible in principle
to operate with sporadic negative power input (cooling) and at zero input
power, once the reaction set point has been established.
This is exactly what is required to nail down the existence of the effect. No
shenanigans with input power are then possible, and there's only one conclusion
possible - that, at steady-state, energy is being generated when no energy is
being input. This is crucial in my view for universal acceptance of the
vailidity of the effect - whatever the details of that effect might be.
Andrew
----- Original Message -----
From: David Roberson
To: vortex-l@eskimo.com
Sent: Saturday, May 25, 2013 10:30 AM
Subject: Re: [Vo]: ECAT Drive PWM Issues
Andrew,
My model demonstrates that a periodic waveform is required in order to keep
the ECAT within stable bounds and at a good COP. If the drive is totally
eliminated then there are two states that can exist. One is for the device
to cool off and reach room temperature and the other is for it to continue
rising in temperature until it can no longer be controlled by the drive
waveform. You can use the final drive state to determine which direction the
ECAT ultimately heads. That is, you can give the ECAT a push toward one of
those two conditions. The positive feedback mechanism takes over after that
final push and carries the order to completion.
Of course, if someone applies super cooling tubes to extract the excess heat
then the thermal resistance will be reduced. Enough of this type of cooling
could reverse the process. If sufficient reduction in thermal resistance is
achieved, the positive feedback instability can be defeated. If the loop
gain becomes less than unity the device would begin to cool toward room
temperature. It is a complicated system with many subtle points to consider.
There may exist some situations where negative feedback occurs, but this is
speculative. I am fairly confident that a limiting mechanism must exist
where the temperature can become no higher. As this temperature is
approached the positive feedback loop gain must become less than unity. When
the gain is reduced below unity stable operation begins and a real SSM
occurs. I suspect that any attempt to gain control by drive alone is
hopeless at these temperatures and the only way possible to cool the device
would be to flush it with coolant.
Dave
-----Original Message-----
From: Andrew <andrew...@att.net>
To: vortex-l <vortex-l@eskimo.com>
Sent: Sat, May 25, 2013 12:47 pm
Subject: Re: [Vo]: ECAT Drive PWM Issues
Dave,
Does this model allow a stable energy production regime to exist when, after
initiation via initial heating has begun, the device can be run at zero input
power, and regulation to prevent runaway is achieved by the application of
sporadic cooling via (say) cooling tubes?
For if the device can indeed be continuously operated at zero (or indeed
negative) input power, then one has unambiguously demonstrated the production
of "something from nothing", and there's no getting away from that.
Andrew
----- Original Message -----
From: David Roberson
To: vortex-l@eskimo.com
Sent: Saturday, May 25, 2013 9:36 AM
Subject: Re: [Vo]: ECAT Drive PWM Issues
Fran, my model takes into account the rate of heat transfer out of the
device by using a parameter that simulates a thermal positive feedback
loop. And, as you suggest this depends greatly upon the rate of heat
generation with temperature and the thermal resistance that it delivers
that heat into. Another way to think of this effect is to consider what
would happen to a block of active material which is surrounded by a perfect
heat conductor. In this special case, any additional heat that is
generated is immediately absorbed by the conductor and can not raise the
temperature of the block. This would be a stable condition and the COP
would be low. Now, if you modify the surrounding heat conductor by
increasing its thermal resistance then any newly generated heat from within
the block would result in an increase in its internal temperature in a
positive feedback manner. The resistance can be increased until it reaches
a point such that a tiny incremental input of heat to the block results in
a temperature increase of the block that causes additional heat generation
slightly larger than the initial increment. Rossi appears to operate above
this resistance point when his device has the desired performance.
That was a lot of words and I suspect is not clearly written. The meat of
the description is that there will be a temperature that depends upon the
heat sinking where the device becomes unstable and begins to proceed toward
melting. My model suggests that this is the temperature above which Rossi
should operate his device to achieve good COP. The model further
indicates that you can maintain control of the device while operating above
this point as long as you reverse the process before a second temperature
trip point is reached that leads to run away. It is important to realize
that operation within this region is unstable unless a drive waveform is
applied with the proper characteristics.
In the radio world this type of device would be referred to as a negative
resistance component. Rossi must be relying upon the energy generated in
this mode for his large gain. The hard part is to keep the ECAT from
getting out of control since he is operating on a sharp balance to obtain
good COP.
I am not modeling any process that occurs beyond the two temperature trips
that I described since operation above the second one is destructive.
Operation below the first temperature point results in a COP that is too
low to be useful. I have included energy loss due to a 4th order radiation
process in some of my runs, but so far I find that control issues occur
before this has significant effect.
I believe as you do that operation with a heat exchange fluid will be
easier to control. This also allows Rossi to adjust the flow rate which
could be used to modify the thermal resistance factor and thus total loop
dynamics. For example, he could raise the temperature at which the core
become unstable thereby compensating for different core activities.
My model operates upon the average behavior of an ECAT type device. It
assumes that the design has been developed by good engineering processes.
If the design team allows the system to harbor inconsistent heat transfer
such as would occur with too many and too large in size hot spots, then
there is no control technique that will work effectively. I suspect that
much effort will center around making sure this issue is handled.
Dave
-----Original Message-----
From: francis <froarty...@comcast.net>
To: vortex-l <vortex-l@eskimo.com>
Sent: Sat, May 25, 2013 7:16 am
Subject: re: [Vo]: ECAT Drive PWM Issues
Dave, I think you we are both in agreement with the initial post of Ed’s
thermal analysis,
http://www.mail-archive.com/vortex-l%40eskimo.com/msg80803.html but it
does not mention the difference between the destructive test in open air
and the unit in normal operation which is constantly bathed in a heat
extracting fluid.. are you modeling this in your SPICE calculation? The
thermal circuit in the destructive test only has air cooling to keep the
runaway at bay and represents a softer – more fragile target for the
waveforms to temporarily exceed while I think the reactor in heavy heat
sinking mode would have much higher tolerance for controlled PWM
excursions into areas that would be considered runaway if not for the steady
drain.
Fran
[Vo]: ECAT Drive PWM Issues
David Roberson Fri, 24 May 2013 23:30:52 -0700
I was adjusting my spice model of the ECAT when I decided to determine how
important it is to keep the device operating within the normally unstable
region at all times. Here I refer to the unstable region as that operation
range where the ECAT would tend toward over heating unless under control.
There is no end to the questions which keep arising as to how heat can be
applied in the proper format to keep an unstable device operating under control
when it is capable of putting out more heat than required to drive it. And,
the ECAT tends to operate best when the COP is equal to 6 which clearly is
within this mode.
One day this will be accepted. For now, I want to mention that it is important
to keep the ECAT operating near the ultimate thermal run away region. If the
device temperature is allowed to drop too far before the drive returns then the
COP degrades significantly. And, as is somewhat demonstrated by the waveforms
shown in the recent report, the length of time that the temperature hesitates
at its greatest level is determined by how by Coupon Companion"
id="_GPLITA_0"close to that ultimate run away
temperature the device operates.
My test runs demonstrate that the ECAT needs to be operating at a maximum
temperature near to its ultimate thermal run away point and that the variation
in output temperature needs to be maintained low by timing of the PWM drive.
Both of these requirements should be met if the ECAT is to deliver the desired
COP of 6 and remain stable. My spice model offers good guidance even though it
can only approximate a real device.
Dave
