Rossi Lugano/early demo's revisited. (technical)

  • Always astounding this thread !!

    So many anti rossi cross here those who believe in it anyway.

    I will remain neutral for myself therefore how much do experts estimate internal temperature inside Lugano's reactor finally ?

    DF

  • Always astounding this thread !!

    So many anti rossi cross here those who believe in it anyway.

    I will remain neutral for myself therefore how much do experts estimate internal temperature inside Lugano's reactor finally ?

    DF

    With an external temperature of 800 C, the internal (central) temperature would be about 980 C.

    That is based on direct experimentation using a Durapot 810 cylinder with internal and external thermocouples.

    At 895 C, the internal temperature would be (is) 1110 C.

    At 700 C, the internal temperature would be (is) 833 C.

    You may extrapolate to 1410 C external if you like.

  • With an external temperature of 800 C, the internal (central) temperature would be about 980 C.

    That is based on direct experimentation using a Durapot 810 cylinder with internal and external thermocouples.

    At 895 C, the internal temperature would be (is) 1110 C.

    At 700 C, the internal temperature would be (is) 833 C.

    You may extrapolate to 1410 C external if you like.

    Thanks Paradigmnoia for your reply,

    if i well understand you suggest no more than 200° difference between Inside/ouside.

    Around 1000°, this is the limit explained by J.Ruer At Airbus WS to avoid runaway. This is also in relation with our understanding of cat/mouse concept requested by Focardi.

  • Thanks Paradigmnoia for your reply,

    if i well understand you suggest no more than 200° difference between Inside/ouside.

    Around 1000°, this is the limit explained by J.Ruer At Airbus WS to avoid runaway. This is also in relation with our understanding of cat/mouse concept requested by Focardi

    The difference between inside and outside temperature increases with increasing temperature. The hotter alumina gets, the more the alumina heat conductivity drops.

    I would estimate that the internal temperature of the tube at 1400 C outside to be about 1750 C.

    At 895 C external the internal temperature is already 215 C hotter.

  • External 18.4 ...... Internal 18.4

    External 254.4 .... Internal 271.2

    External 475.1 .... Internal 534.8

    External 635.7 .... Internal 744.7

    External 700.2 .... Internal 832.7

    External 735.5 .... Internal 907.0

    External 805.1 .... Internal 985.9

    External 835.8 .... Internal 1033

    External 894.5 .... Internal 1111

  • Thanks for reply, therefore i can not imagine that inside temperature could go beyond powders melting point ?


    DF

    It cannot go beyond the Kanthal melting point. The Kanthal coil would be hotter than the outside, and nearly as hot (if not as hot) as the inside. In practice, one can rarely even go as high as the theoretical Kanthal melting point. The Kanthal wire usually fails before the melting point.

  • Around 1350 C is the practical (and short term) limit of 23 ga Kanthal A1 (the size I prefer to use). It can go a little higher, but only briefly.

    Alan S might have some experience with the practical limit of 18 ga Kanthal (I think that is what he uses if I recall correctly)

  • You should also take in account that XH go out by bursts and must punctually exceed kanthal melting point.

    Something like 99% of recent, sensational, and high power XH reports show the the output power totally in step with the input power.

    I find that suspicious, quite frankly. I would expect bursts, or out-of-step heat-input relationships.

    But no matter how the Kanthal gets overheated, once it melts, that's pretty much the end of the experiment. One might also consider that the thermal resistance of alumina means that bursts of internal heat may melt the internal alumina (and/or anything else inside) before the heat can be effectively conducted to the surface. Once beyond the Critical Radius, the alumina is insulation.

  • Something like 99% of recent, sensational, and high power XH reports show the the output power totally in step with the input power.

    I find that suspicious, quite frankly. I would expect bursts, or out-of-step heat-input relationships.

    But no matter how the Kanthal gets overheated, once it melts, that's pretty much the end of the experiment. One might also consider that the thermal resistance of alumina means that bursts of internal heat may melt the internal alumina (and/or anything else inside) before the heat can be effectively conducted to the surface. Once beyond the Critical Radius, the alumina is insulation.

    yes, I agree, it remains speculative however what incredible results do you refer to?

    Apart incredible little oversold XH from last ICCF, i don't know any ?

    Also, I agree with your mistrust about XH signal found too perfect.

    DF

  • A couple of observations/ I use 0.9mm Kanthal, thinner than the stuff Rossi uses. It is very rare I push a reactor over 1000C, I think 1250 is as hot as I have ever gone (internal temperature) but I have never experiences a coil failure even after 100+ hours at that temperature.


    On the correlation of XSH with input power, yes it might look fishy - can even be fishy - but there is a clear correlation between system temperature and XSH in many cases, which rather clouds the issue. So take care not to throw out any babies with that bathwater.

  • I agree with Alan


    We had one customer which produced epitaxial high voltage transistors used in the line output stage of TV's.

    That epitaxial process was running at just over 1300 degree C

    While our Kantal heating elements had much larger diameters the those used in LENR reators, we never saw that element fail while it was running 24 hours a day.

    So it seems that Kantal wire is quite resistant to failure, even at high temperatures.

  • Yes Alan, you are right Kanthal label remains really reliable. For example, from our side we use Nichrotal 0,2 mm AC power up to 1000° without problem.

    We don't lie to ourself if XSH looks too fishy probably because nothing was released !

    Therefore what could you tell us about Shongsheng charts ? About its TC i'm agree when broken you should read less power reading than more, of course.


    Now, I either didn't understand last sentence/English humor sorry, you help me ?

    DF

  • Lugano stacked tubes correction factor


    I was finally able to extract the convective heat flux values from my CFD simulation software.

    Both the convective heat flux values of the simulation of a single tube and the stacked tubes where calulated. This was done for rod temperatures of 50, 75, 100, 125 and 150 degree C.

    These temperature values cover a large range of the measured stacked tube temperatures in the Lugano report.

    All simulations used a fluid (air) temperature of 21 degree C.

    The properties of the fluid (air) where for the simulated rod temperatures determined based on the film temperature ( (air temperature + rod temperature)/2 )

    From the calculated heat fluxes at each simulation temperature the correction factor was calculated in the following way :


    Correction factor = Total heatflux of three stacked tubes / ( 3 x heat flux of single tube)


    The calculated correction factors for each simulated temperature can be found in the following table :


    -----------------Temperature (C)---------Correction factor

    ------------------------50-------------------------0.555

    ------------------------75-------------------------0.563

    -----------------------100-------------------------0.573

    -----------------------125-------------------------0.553

    -----------------------150-------------------------0.559


    The values are relative constant over all temperatures, the average value being 0.561

    This value is as was expected indeed lower then the factor of .667 (2/3) which the Lugano testers used for correcting the convective heat of the stacked tubes.

  • What is the conclusion LDM, instead of your rebus (humor), what temperature max in the heart of lugano's reactor? Following your understanding ?....

  • What is the conclusion LDM, instead of your rebus (humor), what temperature max in the heart of lugano's reactor? Following your understanding ?....


    I have to admit that I have currently no idea what the maximum temperature inside the Lugano reactor would have been.

    It depends on the temperatures and we don't know if the reported ones are correct.

    An option is to use the data Para supplied to you and make up your own estimate