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Ignition temperature

  1. May 15, 2005 #1
    Does gasoline have a higher ignition temperature then ethanol? (all other things being equal like pressure) Also does a higher ignition temperature mean that it will produce more energy upon combustion? Thanks in advance.
  2. jcsd
  3. May 15, 2005 #2
    I think that the ignition temperature of ethanol is roughly 30 degrees higher than gasoline

    But I do know that if one looks at the energy content in Nett MJ/kg on sees than ethanol has a value of 26.68, whereas gasoline has a value of 42 - 44. So gasoline has a higher energy content.


  4. May 16, 2005 #3


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    To be sincere I don't know. Maybe you could find in a table the maximum adiabatic flame temperature of each substance. Also I think there is none general correlation between maximum adiabatic flame temperature and heat power released.

    Another possibility is to ask to F.A. Williams, the combustion expert of your University.You know, in some class, hand up and ask, and then you tell me what he says to you. :biggrin: Do you know him?
    Last edited: May 16, 2005
  5. May 16, 2005 #4


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    For properties of fuels, see -

    http://www.eere.energy.gov/afdc/altfuel/fuel_properties.html [Broken]

    Look for - General Table of Fuel Properties - and download pdf file.

    For heat of combustion of octane and ethanol, look at


    Gasoline has more C-C and C-H bonds. IIRC, the C-OH is a disadvantage energy-wise.
    Last edited by a moderator: May 2, 2017
  6. May 16, 2005 #5
    Last edited: May 16, 2005
  7. May 16, 2005 #6
    I don't believe I know him. I am in the bioengineering dept. (undergrad). What department is he in?
  8. May 17, 2005 #7


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    He's in MAE and he is the director of the Center for Combustion Research.

    At least, don't you know Prof. Lasheras?, the MAE chairman? He's an spanish aeronautical engineer.
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