LDM Member

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  • LDM

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    Rod temperatures Lugano active run period 16 if factor 2/3 was not applied




    When the factor 2/3 was not applied to the rod power, we have the following data

    Convective power--------87.94 Watt
    Radiated power-----------88.47 Watt
    Total power
  • LDM

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    This is intended to work with Rods, but I haven’t made immediate plans for them yet.

    I am currently working out the best casting method to get all the wires in place and a tiny hole down the center for a moveable thermocouple. I probably need to get…
  • LDM

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    Paradigmnoia

    Are you also in some way going to simulate the interaction with the rods.
    This since the interaction with the rods is limiting the heat transfer of the outer side of the end caps.
  • LDM

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    (Quote from Paradigmnoia)


    It is indeed correct that this is not explicitly shown in the report and your further remarks are to the point.

    So i propose based on my previous post to base the calculation of Lugano run period 6 for the case the…
  • LDM

    Post

    Rod temperatures of Lugano active run period 16 if broadband insted of in-band emissivities on the Optris where used

    In order to be able to calculate the lower rod power of the Lugano active run period 16 in the case that the measured temperatues…
  • LDM

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    (Quote from Paradigmnoia)


    In my opinion there is another effect in play
    The ribs closest to the caps and the inner side of the heated caps are viewing each other for a significant part.
    Since both are at elevated temperature, the heat exchange of the…
  • LDM

    Post
    (Quote from Paradigmnoia)


    What I learned from interpreting some simuations is that the following might be the case

    1. To get to the reported cap temperatures, the heater coil might have been running for some length also under the end caps

    2. You can…
  • LDM

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    (Quote from LDM)


    Possible that the wire had been 'notched' a little during the winding process. Generally it is necessary to grip the end few feet of a wire very firmly while the last turns are laid down Excessive force or the wrong pair of grips…
  • LDM

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    (Quote from Paradigmnoia)






    I have been going over the construction of the MFMP Dogbone replica of the Lugano device.


    An important aspect is the lead passing through the Cap. The '3 phase' version (3 windings, but wired in series outside of the caps due
  • LDM

    Post
    (Quote from Paradigmnoia)



    I completed as per your request the spreadsheet for the COP 5 version.
    See attachment.

    I still need to make a start on the one for the recalculated lower temperatures.
    (Working now on how to get the temperatures of the rods,…
  • LDM

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    Length of heater wire in the rods

    A few weeks ago I did some analysis using data from the MFMP thermal dogbone test based upon the adapted emissivities which I found to limit the errors between thermal and applied powers.
    I assumed two different…
  • LDM

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    (Quote from Paradigmnoia)


    What about using as a first approach a 30 mm stainles steel tube coated with a Durapot layer to get the emissivity in line ?
    Much cheaper.
  • LDM

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    Suggestion for the rods:

    Take a 3 cm diameter, 50 cm long ceramic pipe (or from another material which can stand the temperature).
    Stick the halve of a heating element (coil, power resister) in at one side.
    The part sticking out simulating the heated…
  • LDM

    Post
    Paradigmnoia


    Your modified e in your Dummy spreadsheet due to IRM and View Factor seems OK to me in general.


    When viewing the output power distribution Rods%/Caps%/Ribs% the Rods seem (to me) to have a larger than expected proportion of the output
  • LDM

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    Paradigmnoia  


    Actually, does the View Factor adjustment take into account the normal-viewed area of the tips of the ribs versus the V-cavity area?

    The view factor is the value which indeed takes into acount the change in view from the valey to the…
  • LDM

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    Paradigmnoia



    Perhaps the apparent low power, after reducing the T from near 1400 C to near 800 C, is due to not correcting the emissivity for the ribs in the output power calculation?

    It is not clear for me what you are meaning by the above text.
  • LDM

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    (Quote from Paradigmnoia)


    The inner temperature is indeed lower.
    But I explained already that this was because I was reporting average temperatures.
    And since the reactor core is longer then the ribbed area, the average of the reactor core includes much…
  • LDM

    Post

    Good to hear you have a source that may help shed a little light on it.

    The information above was told to me without me asking for it
    I am not asking my source for further information, but can confirm from what was told to me that the E analysis of…
  • LDM

    Post
    They explicitly explain the flawed method, and include examples.




    If they used wrong emssivities, in my opinion they would afterwards have considered this to be the most importantant shortcomming in their measurements.
    However I was told by somebody…
  • LDM

    Post
    Paradigmnoia


    1. At the Dummy temperatures the emissivity changes have a minor effect. This was clear on my graph. There is enough wiggle room that the temperature-power error can be fudged away. Regardless, the Professors wrote numerous comments