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Heat given by a flame

  1. Jun 2, 2005 #1

    First of all, I'm french, as a consequence my scientific language might be difficult to understand. I'm sorry for this.

    So, I'm studying a little Stirling motor.
    I evaluated the Work given by its cycle. It functions with an external combustion, produced by the burning of Ethanol (C2H5O).

    I want to calculate the Heat given by the flame provided by this combustion in order to calculate the output of my motor.

    Does anyone have an idea ? I thought about the use of the Free Enthalpy of Combustion, but I don't understand how to use it.

    Maybe I could use the expression :
    Variation of enthalpy = C*variation of temperature ?

    Thanks for your help =)
  2. jcsd
  3. Jun 2, 2005 #2


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    Are you referring to free energy? You might want to find the standard enthalpy of reaction instead. The data is quite easy to find.
  4. Jun 2, 2005 #3
    That must be that (attached with the post).

    But with that, how could I calculate the heat given by my flame ?

    Attached Files:

    • img1.png
      File size:
      324 bytes
  5. Jun 2, 2005 #4


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    I think that enthalpy is a good approximation of the heat [itex] q [/itex] in most cases,
    to be sure and perhaps obtain more professional advice you'll need to post this question in the engineering forum and be sure to mention "Sterling Motor."
  6. Jun 2, 2005 #5
    Ok, thanks a lot for your help =)

    I'll first try to get the plans of my motor to be more precise.
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