[danago]

Hey.
I am in the middle of completing a chemical thermodynamics assignment, and just as i completed one of the questions, i thought of something that i should confirm. My question is more about semantics rather than the actual thermodynamics, so i will start with a brief outline of the problem statement.

The assignment involves the combustion of methane with pure oxygen, carried out adiabatically and at constant pressure. The main twist in the question is that the reaction does not proceed to completion, with the assumption that the only products are CO₂ and H₂O.

One of the questions i need to answer involves the calculation of the adiabatic flame temperature for methane in this context. What i am not sure about relates to the definition of the flame temperature -- Does the adiabatic flame temperature of a fuel assume a complete combustion, or will it depend on the extent of reaction? Is there a standard definition that engineers use in practice?

Thanks in advance,
Daniel.

[mbeychok]

Almost all calculations of adiabatic flame temperatures (usually for process furnaces and steam generator furnaces by chemical engineers doing process designs) assume complete reaction of fossil fuels (natural gas, petroleum fuel oil, coal) to CO₂ and H₂0 ... at least that has been my experience. If the fuel contains significant amount of sulfur or sulfur compounds, complete combustion to SO₂ is also assumed.

Perhaps some researchers might consider incomplete complete combustion when calculating adiabatic flame temperatures.