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Fuels Air Flue Gas

Reference data and engineering information about fuels air flue gas for combustion applications.

fuelsairfluegas

Overview

Engineering reference data for Fuels Air Flue Gas in combustion engineering.

Key Formulas

Heat Release

Q=m˙HVQ = \dot{m} \cdot HV

Fuel energy release rate.

Air-Fuel Ratio

AF=mairmfuelAF = \frac{m_{air}}{m_{fuel}}

Mass of air per mass of fuel.

Excess Air

EA=O221O2×100%EA = \frac{O_2}{21 - O_2} \times 100\%

From flue gas oxygen measurement.

Variables

SymbolDescriptionUnit
QQHeat release rateW
m˙\dot{m}Mass flow ratekg/s
HVHVHeating valueJ/kg
AFAFAir-fuel ratio

Combustion Air and Flue Gas Data

The following table provides theoretical combustion air requirements and theoretical flue gas volumes for common fuels. All volumes are measured at standard pressure (1 atm, 0°C).

13 rows
Theoretical combustion air and flue gas volumes for common fuels
Fuel
Type
Theoretical Air
Theoretical Air
Theoretical Flue Gas
Theoretical Flue Gas
AnthraciteSolid9.41509.5152
Bituminous coalSolid6.91107112
CharcoalSolid8.41348.4135
CokeSolid8.41348135
LigniteSolid5.7928.493
PeatSolid5.7925.994
Semi anthraciteSolid8.41358.6137
Wood (dry)Solid4.470580
Butane (C₄H₁₀)Gas313133.433.4
Natural gasGas9.59.510.510.5
Propane (C₃H₈)Gas23.823.825.825.8
Gas oilFluid9.8157010.41670
Heavy fuel oilFluid10.8173011.61860

Source: engineeringtoolbox.com

Units by Fuel Type

Fuel TypeAir (Metric)Air (Imperial)Flue Gas (Metric)Flue Gas (Imperial)
Solidsm³/kgft³/lbm³/kgft³/lb
Gasesm³ air/m³ fuelft³ air/ft³ fuelm³ gas/m³ fuelft³ gas/ft³ fuel
Fluidsm³/literft³/galm³/literft³/gal

Important Notes

  • Stoichiometric combustion: The data assumes complete (stoichiometric) combustion with no excess air
  • Density relationship: Combustion of a fuel gas produces flue gas with higher density than both the original fuel gas and the combustion air
  • Standard conditions: All volumes are measured at standard atmospheric pressure (1 atm / 101.325 kPa)

Interactive Charts

Flue Gases - Dew Point Temperatures

References