David Roberson December 30th, 2013 at 11:54 AM Dear Andrea,
I have been following your progress for a long time and wish to congratulate you for the hard work and amazing accompolishments. I wish that there were some way that your ECAT could be introduced to the world quickly since it will open many doors that are currently nearly shut by the high cost of energy. As you may know, I have constructed a computer model of the ECAT type system which offers insight into the operation of your device and demonstrates many of the difficult problems which you must overcome in order to make your design practical. You continue to state that the COP will be at a minimum of 6 which is consistent with my model. To achieve a significantly higher COP and maintain stability, it will be necessary to push the internal temperature closer to the point at which the device undergoes thermal run away and that of course would offer difficult challenges. The model strongly supports your operation statements where input power is applied for 1/4 of the time while the device runs in self sustaining mode for the other 3/4 of the time. This duty cycle should be adequate for operation within the region of thermal positve feedback, with a loop gain of greater than unity, provided the internal temperature is allowed to approach the run away point. The closer you operate to this temperature, the higher the net COP will be. The control system must be able to enact a turn around to the direction that the internal temperature is moving at the correct times. The positive feedback takes over once the direction is changed and the ECAT internal temperature continues along that path until the next input power change is enacted. Operation of this type is not easy to visualize and I am confident that that is why so many can not grasp how heat can be used to control a greater amount of internally generated heat. There have been many posts on Vortex-l where I have attempted to explain this behavior and it still remains a mystery to most. Several readers have asked what happens if you cut off the controlling heat source. They fear that thermal run away must begin at that point, but this is not the case. The model suggests that the device will immediately begin to cycle downwards in temperature until it cools down completely. The positive feedback will ensure that this occurs. Although it may seem strange, the fact that the drive power is applied at its full level is an important component to this behavior. Your mention that the internal temperature must be in the vicinity of 1000 C in order to deliver heat into a coolant at 500 C or so makes perfect sense. That is one of the variables that you must control in order to set the internal thermal run away trip point at the ideal location. The input temperature and the flow rate of the coolant are other handles at your disposal. So, I find it particularly interesting to follow your recent statements on this journal as you slowly reveal how the ECAT funcions. All of them have been supported by my computer model and I hope that you will continue to offer more insight to us. The wait for your product to be perfected may not be long now. Thank you for your fine efforts, David Roberson - - - Andrea Rossi December 30th, 2013 at 1:54 PM David Robertson: Thank you for your insight. Warm Regards, A.R.
