Combustion Air Flow Calculator

Converting Air Mass Flow Into a Fan-Sizing Number

Combustion calculations naturally work in mass (kg of air per kg of fuel), but fans and ductwork are sized by volumetric flow. This calculator bridges the two using air density at supply conditions.

The Formula

Volumetric Flow = Mass Flow / Air Density

Worked Example

A burner needs 1,200 kg/hr of air at a density of 1.2 kg/m3:

Flow = 1,200 / 1.2 = 1,000 m3/hr

How to Use This Calculator

  1. Enter the Air Mass Flow rate.
  2. Enter the Air Density at actual supply temperature and pressure.
  3. Select Calculate to get volumetric flow rate.

Related Calculations

Need duct velocity from this flow? See the Combustion Air Velocity Calculator, or check gas density directly in the Gas Density Calculator.