Posted on 04/29/2013 2:51:25 PM PDT by Kevmo
Steel & Glass Cells : Preliminary Test Findings [UPDATE #1 - Wire capability?]
on 28 April 2013.
First, can we say a HUGE thankyou to you guys for making this cell construction possible. Your donations have made a big contribution to the costs of developing this flexible cell that has great potential. Nicolas Chauvin has worked extremely hard to put this together with input from other members of the team particularly Mathieu and Ryan. Also the instrumentation and control package was put together by the US team and will also be funded by your donations. THANKS - FOR MAKING THIS POSSIBLE!
The purpose of the stainless steel and glass dual envelope cell design is to improve the output heat measurement of Celani’s cell design by capturing as close to all the heat coming from the cell.
The internals of the cell is similar to Celani design with two wires winded around mica support. The glass tube is also made of borosilicate and can support up to 8 bars at 350°C.
The main difference is the use of a single ended tube to reduce the leakage of hydrogen or other choices of inner cell atmospheric composition.
The tube is sealed onto a stainless steel flange with special Teflon gasket with a silicon core.
Between the glass tube and the stainless steel envelope, it is also possible to choose the gas composition and pressure. This allows fine tuning the heat flux conductivity between the cell and the outside environment. With 0.15 bar of helium in this middle chamber and 80 Watts input, the cell temperature can go up to 350°C when the cell is immersed into ambient temperature water. So far, in preliminary tests, the pressure inside the glass tube and in the middle chamber have been very stable with very limited leakage even when using hydrogen and helium.
With this configuration most of the heat flux going outside the cell is from radiation through the glass onto the stainless steel outer envelope. Since the cell is almost completely immersed in water, the heat is accumulated into the water.
To get a good feedback of radiated heat, 3 thermocouples have been placed on copper rings around the glass tubes. These rings act as heat integrator to avoid measuring temperature at a very specific point on the glass surface.
Finally, we measure the evolution of water temperature in large volume baths (big water buts) to get a good idea of the output heat.
To get a precise measurement of the excess power, we have built two cells that have the exact same construction. Our preliminary test has been configured with one passive cell which is used as a control cell. It is loaded with 2 Nichrome (NiCr 80:20) wires. The second cell is active and is loaded with 2 Celani Constantan wires (low number of layers). In order to avoid the need for cell calibration and modelling of temperature to output power, we have chosen to manually fine tune of the input power of the passive cell in order to match the water temperature in the 2 setups (active & passive).
In our preliminary experiment, after successfully loading the Celani wires with Hydrogen, we have been applying 84.8 Watts input power in the passive cell and 80.0 Watts in the active cell to maintain very similar water temperatures (± 0.1 °C) in the same large volume of water.
This early test suggests that it takes 6% more power to maintain the same volume of water at the same temperature in the control cell when compared to the active cell. This is also the first experiment where we have two lengths of Celani wire ( one 14L one 16L and around 550mg of wire) in the same active cell.
When applying the same 80 Watts in both cells, we could measure about 1.5°C temperature difference in favor of the active cell. That is to say, 80W raised the water temperature from 20 to 30 degrees, but in the active cell, it was 1.5°C higher so the gain is of the same order as the preliminary findings where the same temperature is maintained by a lower power in the active cell's bath.
The evaporation has shown to be practically identical for both cells from. As we move forward we want to ensure high accuracy on the amount of water in each of the baths and to ensure they are carefully mixed. A first check will be to swap the cells into the opposite water bath.
We hope to get the live Feed up and look out for up and coming video!
As ever - add your comments and suggestions below.
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UPDATE #1 - Wire capability
Celani called today to say how positive he was about these preliminary results, it was suggested that we have some things to tidy up with the design of the experiment but that it was encouraging. He then went onto say that the reason was that we are using the least capable wires, so we asked for an explanation.
Basically, the 2L wires are better than the 14/16L wires because of the positive effect of the nano-diamanoids. The process used to add the extra layers destroys these diamondoids and the extra layers do not benefit sufficiently until the number of layers are far higher. In terms of Mechanical stability, the 2L is the best and the 700L is extremely fragile. However, the order of claimed excess power potential superiority of wires is like this, from the top down:-
Class 700L 400L 250L 2L 14/16L
So.... in theory, the only way is up!
Good careful experimental work going on here. Shows that good science can be done w.o. billion dollar budgets (not the CF has ever “had” any such budget).
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