Bob, You are bringing up good points. Perhaps Jed or Mizuno will have an opportunity to pursue a cleanup effort to eliminate these noise items. Do you have time to follow up on this idea to see if the numbers we are getting make sense? I have never had an opportunity to go into the details like is happening now with regard to thermal measurements. I have chased down plenty of other forms of analog noise, but not this particular type.
Could it be that we are expecting better input than is normally possible? I am amazed to see how low the total temperature errors appear to be according to my simulation output. I had no idea that .02 degrees of temperature change could even be measured with normal lab equipment. The calculations can be done to many decimal places, but if the input is not accurate enough then the final results must be limited. When I started this project I figured that .1 degree accuracy would be about as good as I could hope to determine. I have been pleasantly surprised so far. Something might come up that bites me in the rear, but so far so good. :-) Keep asking those important questions and sharing your impressive systems knowledge. Dave -----Original Message----- From: Bob Cook <[email protected]> To: vortex-l <[email protected]> Sent: Sat, Jan 31, 2015 6:32 pm Subject: Re: [Vo]:Alternate Calculation and Calibration Method for Mizuno Report Dave- My experience with older thermocouples is that reference t/c voltages must be well controlled to get accurate temperature readings based on calibrations. It looks to me like the reference voltages that the t/c instrumentation uses may have a cyclic variation that is responsible for the cyclic variation your model predicts. I wonder what the instrumentation specs say about this issue. It would be useful to review those specifications and what the vendor says about stability of the readings. Frequently T/C leads need to be electrically shielded to prevent small voltage pickup and disruption of the voltage determination. With the small temperature changes only very voltage changes are produced by the t/c's--millivolts and less. Bob Cook ----- Original Message ----- From: David Roberson To: [email protected] Sent: Friday, January 30, 2015 6:07 PM Subject: Re: [Vo]:Alternate Calculation and Calibration Method for Mizuno Report This is an ongoing project I suppose. I will check the Oct 20 data again, but I believe I got roughly the same amount of excess. That seems too good to be true. What do you mean by considering that the reactor vessel is capturing 60% of the heat? Are you referring to the idea that the water and reactor have a combined capture of 100%? That would seem logical if the thermal capacity of each is considered. It is good to continue with the calibrations and I hope that the ambient is better controlled at this phase. We can make the calorimeter work well once it is properly compensated to take out the signal droop. The main issue is to keep the ambient variations to a minimum. One thought to consider. If something happens to disrupt the system, you can wait a few time constants until the ambient average changes work their way out of the calorimeter system. A good test of that condition is to measure the difference between the ambient and the coolant. Once that difference is equal to the nominal value set by the product of the thermal resistance and the leakage powers, you are good to go. Of course, you must ensure that the ambient is not varying too far since that immediately impacts the heat flowing into and out of the thermal capacity. It is assumed that the average ambient is constant which will prevent any major transients. This system should work well with the right precautions and compensations. Dave -----Original Message----- From: Jed Rothwell <[email protected]> To: vortex-l <[email protected]> Sent: Fri, Jan 30, 2015 8:48 pm Subject: Re: [Vo]:Alternate Calculation and Calibration Method for Mizuno Report David Roberson <[email protected]> wrote: I do not get anywhere near to the 3 to 1 excess power out over input power that is reported. I am seeing a 1.25 ratio instead of 3.0 or so. Oh, I think you did see the 3 to 1 excess, and the 6:1 as well. Keep looking! Look at Table 1. You got 1:1.25 for the water on Oct. 21. Right? I estimate 1:1.35, which is close enough. Now look at Oct. 20, which got a much better ratio with the water, 1:2.29. NOW add in the heat captured by the stainless steel reactor vessel. The thermal mass of the reactor is larger than that of the water, so I estimated that the vessel captures 60% of the heat, and the water 40%. So, the combined ratio for Oct. 20, for the water and stainless steel, is 1:5.69 Try applying your method to the Oct. 20 data and see if you get an answer in the same ballpark. Additional calibrations are underway. I believe I will soon be able to confirm that the reactor vessel is, in fact, capturing 60% of the heat. - Jed
