Chemistry & Reaction Engineering
Thermochemistry & Combustion Simulators
A focused Chemistry & Reaction Engineering hub for thermochemistry & combustion tools, keeping related formulas, assumptions, and engineering checks together.
5 simulators
Adjacent categories
Simulator list
Adiabatic Flame Temperature Simulator
Thermochemistry & Combustion
Compute the theoretical upper-limit temperature (adiabatic flame temperature T_ad) reached when a fuel burns in air.
Combustion Stoichiometry & Flue Gas Calculator
Thermochemistry & Combustion
Calculate stoichiometric air-fuel ratios and flue gas composition instantly. Select your fuel and excess air factor for complete combustion analysis.
Mixing Entropy Simulator — Ideal Gas Three-Component Mixing
Thermochemistry & Combustion
Compute the mixing entropy Delta S_mix = -n R Sum x_i ln x_i for a three-component ideal gas in real time from total moles n, mole fractions x_1, x_2, x_3 and temperatur…
Fuel Heating Value & Thermal Efficiency Calculator
Thermochemistry & Combustion
Calculate fuel heating values (LHV/HHV), thermal efficiency, SFC, and CO₂ emissions for engines and boilers with this comprehensive online tool.
Stoichiometric Air/Fuel Ratio Simulator
Thermochemistry & Combustion
A tool to calculate the amount of air "just sufficient" to fully burn a hydrocarbon fuel CxHyOz. Change the carbon and hydrogen counts and the equivalence ratio phi to s…
How to Use
- Select fuel type (natural gas, diesel, coal, biomass) and specify composition by mass fraction or molar ratio
- Set inlet air temperature, pressure (kPa), and stoichiometric ratio (lambda) for lean/rich combustion analysis
- Input desired outlet temperature or adiabatic flame temperature assumption, then run equilibrium solver to obtain products, heat release (MJ/kg), and pollutant yields (NOx, CO, soot formation)
Worked Example
Methane combustion at lambda=1.1 (10% excess air): CH4 inlet at 25°C, 101.325 kPa with dry air at 20°C. Stoichiometric reaction yields adiabatic flame temperature 1957 K. With 10% excess O2, flame temperature drops to 1847 K, CO concentration falls from 89 ppm to 12 ppm, and NOx formation (via Zeldovich mechanism) reduces from 247 ppm to 156 ppm. Heat released: 50.0 MJ/kg methane.
Practical Notes
- Use lambda >1.0 for industrial burners; lambda=1.05–1.15 balances emissions and efficiency in natural gas boilers
- Adiabatic flame temperature assumes zero heat loss; real furnaces run 200–400 K cooler due to wall losses and radiation
- CO formation spikes when lambda <0.95; incomplete combustion wastes 2–5% fuel energy
- Gibbs free energy minimization required for accurate equilibrium K values above 1500 K; ideal gas assumption valid up to 3000 K at atmospheric pressure