🔥 Combustion & Adiabatic Flame Temperature
Analyze combustion of hydrocarbon fuels. Compute stoichiometric and actual air-fuel ratios, flue gas composition, adiabatic flame temperature, and dew point of combustion products.
📝 Configuration
CₓHᵧOᵤ + a(O₂ + 3.76N₂) → xCO₂ + y/2 H₂O + 3.76a N₂
a = x + y/4 − z/2
AFR = (a/0.21) × 28.97 / M_fuel
T_ad from ΣH_react = ΣH_prod(T_ad)
φ (equivalence ratio) = AFR_stoich / AFR_actual
📊 Results
Configure inputs and click Analyze to view results.
📘 Methodology
Stoichiometry
Complete combustion of a hydrocarbon fuel CₓHᵧOᵤ with air yields CO₂, H₂O, and N₂. The stoichiometric O₂ requirement is a = x + y/4 − z/2 moles per mole of fuel. Excess air ensures complete combustion in practice.
Adiabatic Flame Temperature
T_ad is the maximum flame temperature assuming no heat loss. It is found by equating reactant and product enthalpies: ΣH_react(T_inlet) = ΣH_prod(T_ad). The calculation uses constant average c_p values for each species.
Flue Gas & Dew Point
The flue gas composition depends on fuel type and excess air. The dew point is the temperature at which water vapor in flue gas begins to condense, determined by the partial pressure of H₂O. Operating below dew point causes corrosion.