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Diesel combustion and gas laws

  1. Aug 15, 2008 #1
    Hi all, new guy here. I am trying to understand the laws that govern a diesel motor. I know it compresses air at about 17 to 1 to ignite the fuel and I think that fuel will expand the air in the chamber at about 5 times the volume consistently (from tdc to end of stroke). I am trying to figure how many BTUs is used to heat the combustion stroke. Also, is the volume of liquid diesel added to the air important to the volume of the chamber (apart from igniting and expanding the air). I have tried to understand this with V1*P1/T1=V2*P2/T2, including using Kelvin and Pa, but could not make the numbers work.

    I hope I have phrased this properly.

    This is the first of a few questions to come

    Thanks in advance
    Denis D.
  2. jcsd
  3. Aug 15, 2008 #2


    Staff: Mentor

    Hi Denis,

    Welcome to PF. The amount of BTU's released would be equal to the specific heat of combustion of the diesel fuel times the amount of fuel, but I don't know what either of those two numbers are.
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