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Measuring the temperature of a combustion

  1. Aug 17, 2011 #1
    I am not 100% certain this is the best place for this. Moderators, if you think a different board would be better, please relocate this. Anyway...

    I am wanting to measure the peak temperatures of my combustions of hydrogen. I got to thinking, "If I am using air as the source of oxygen, then nitrogen is also present. Ergo, nitrogen oxides could be forming."

    Problem is, I have no idea how to even go about measuring the peak temperatures achieved. It is such a brief thing. I cannot really even measure just how short the instantaneous little bangs are.

    Do you guys have any thoughts or ideas? I can assume a certain number of Joules based on the amount of hydrogen. But I cannot measure the duration of a combustion, nor do I know of a way to measure the peak air temperature during it.

    From what I have read, I need to keep it below 1540 degrees Celsius to avoid the production of oxides of nitrogen. I am guessing that using no more than a certain amount of hydrogen in a given time period will allow me to achieve such. Again, I do not know how to go about measuring just how high the temperature of the air is getting, so as to confirm such and set a limit.
     
  2. jcsd
  3. Aug 18, 2011 #2

    Borek

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    Staff: Mentor

    Just to clarify: seems like you are dealing with explosions, not continuous combustion (like in a burner)?
     
  4. Aug 18, 2011 #3
    Yes. Quick explosions, not a continuous combustion.

    I am ultimately looking to produce a succession of little pops.

    Currently, I am thinking about 50 mL (at atmospheric pressure) per second. Should that result in peak temperatures in excess of about 1500° C, I will want to reduce it to whatever lesser amount is necessary.
     
  5. Aug 18, 2011 #4

    Fra

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    The first idea that comes to my mind is real time thermal imaging camera, the same that's used for flame detection and similar? And then find a calibration to peak temp. However one would have to look at the spec to see what equilibration time is needed, I have no clue.

    But there are some heat cameras that surely go up to 2000C and that at least give a framerate of 50Hz. But still 20ms is a large timeframe for an explosion :frown:

    One company I know of is http://www.flir.com/thermography/eurasia/en/content/?id=32092

    If this fails then maybe more subtle ideas are needed.

    /Fredrik
     
  6. Aug 18, 2011 #5
    Is it possible to calculate the peak temperature? And, if so, for calculating whether the N2 is getting hot enough to deprotonate, should I use the heat capacity of nitrogen, or that of air?
     
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