ASTM D6446 Estimation of Net Heat of Combustion of Aviation Fuels
ASTM D6446 Standard Test Method for Estimation of Net Heat of Combustion (Specific Energy) of Aviation Fuels
5. Procedure
5.1 Determine the hydrogen content of the sample to the nearest 0.01 mass %, as described in Test Method D3701, D4808, or D5291.
5.2 Determine the density at 15 C of the sample to the nearest 0.5 kg/m3, as described in Test Method D1217, D1298, or D4052 or Guide D1250.
5.3 Determine the sulfur content of the sample to the nearest 0.02 mass %, as described in Test Method D129, D1266, D1552, D2622, D3120, D4294, or D5453.
6. Calculation
6.1 Calculate the net heat of combustion of the fuel at constant pressure by inserting the measured values of hydrogen content, density, and sulfur content in Eq 1.
Qp = 37.2889 + 0.566173 H - 0.3266 S - 0.0023003 D
where:
Qp = net heat of combustion, MJ/kg,
H = hydrogen content, mass %,
S = sulfur content, mass %, and
D = density at 15 C, kg/m3.
6.2 Calculate the net heat of combustion on a volumetric basis by Eq 2.
Qv = Qp D
where:
Qv = net heat of combustion, MJ/m3.
