Approximate mantle burn temperature?

Discussion in 'Fettling Forum' started by ColinG, Dec 7, 2019.

  1. ColinG

    ColinG United Kingdom Subscriber

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    Does anyone know the approximate temperature that a mantle burning kero reaches?
     
  2. Thomas

    Thomas Subscriber

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    I have a type k thermocouple somewhere in the shop, sounds like an great beer fueled experiment for the weekend.
     
  3. Anthony

    Anthony Australia Subscriber

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    I remember reading a while ago that the temperature inside an Aladdin mantle is about 2000F.
    About the temperature of lava.
     
  4. ColinG

    ColinG United Kingdom Subscriber

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    I wondered because I used aluminium for a support rod that is close to the mantle on my Superb and I'd rather it didn't melt!!! I might replace it with steel if I can find some.
     
  5. Thomas

    Thomas Subscriber

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    Aluminum melts at around 1250F and loses strength rapidly over 600F, I'm quite sure that in close proximity to the mantle it would melt.

    Perhaps head to a hardware store and check their supply of bolts.
     
  6. MYN

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    There is something called the 'adiabatic' flame temperatures of different fuels in air. They are theoretical calculated max. values, not the actual temperatures. That puts kerosene-air mix at a temperature slightly in excess of 2000 deg C!
    But in actual, the flames are never adiabatic. Therefore, they'll be considerably lower in temperature.
    I'd say, the actual temperature within the mantle in a kero lantern would fall somewhere between 900-1100 deg C. But as the combustion gases leave the mantle or the flame front, they'll expand and the temperature would drastically fall below anything that would melt brass.
    If you replace the Thorium mantle with an asbestos or metal mesh, the colour of the glow should roughly indicate the temperature as would be radiated from a "blackbody'. You could refer to a colour temperature chart for that.
    Note: the 'colour temperature' of a typical Thorium mantle is well above 2000K, say 2300-2500K, which is approximately indicative of a glowing tungsten filament in an incandescent electric light bulb. But Thorium oxide behaves rather differently from most solid materials when heated. They glow with higher colour temperatures than the actual temperature they're at.
     
  7. AussiePete

    AussiePete Australia Subscriber

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    @ColinG
    Just a thought .... the MilSpec lamp, and including the Colman 252A lantern version has an aluminium tube generator. Mine runs very well with no sign of any aluminium heat degradation to the aluminium generator.

    A4F806C8-87E7-4476-8FD8-DB6E4FC8D890.jpeg

    Cheers
    Pete
     
  8. ColinG

    ColinG United Kingdom Subscriber

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    Ahhh, interesting! I decided to make a steel support anyway as I found a length of rod more or less the right diameter. I have never heard of an aluminium generator before. The heat transfer would be excellent being aluminium and it must be able to withstand the temperatures because... well, it does!
     
  9. Thomas

    Thomas Subscriber

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    The aluminum generator would be cooled by the fuel evaporating in it, same as the water in a boiler tube prevents it from melting down.
     
  10. AussiePete

    AussiePete Australia Subscriber

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    @Thomas
    Good point, that would indeed be the case ...... still it was just a thought. :-k
    Cheers
    Pete
     
  11. JEFF JOHNSON

    JEFF JOHNSON United Kingdom Subscriber

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    Those aluminium vapourisers have been known to crack.
     
  12. Thomas

    Thomas Subscriber

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    Finally got around to measuring the mantle temp. Used a Petromax 829 that was warmed up for 20 minutes and the temp according to the thermocouple was 1988F. 20200124_101750.jpg 20200124_101832.jpg 20200124_101915.jpg
     
  13. podbros

    podbros United Kingdom Subscriber

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    So Thomas, exactly how much beer was used in this alchemic experiment, exactly??? ;)

    Great result! ..and great pics! :thumbup:... and considerably higher than the melting point of Mild Steel :shock:

    Well done!

    regards,
    pb
     
  14. Blueflame Canada

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    What is the function of the copper tube in the preheat cup?
     
  15. Wim

    Wim Subscriber

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    How many °C would that be?
     
  16. steerpike451

    steerpike451 United Kingdom Subscriber

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    About 1085 C according to an online converter
     

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