ASTM D3338 Test Method for Estimation of Net Heat of Combustion of Aviation Fuels
8. Report
8.1 Report the result from 7.1 to the nearest one-thousandth as net heat of combustion of the fuel in megajoules per kilogram or from 7.2 to the nearest integer as net heat of combustion of the fuel in [Btu per pound].
8.2 Report whether the result is determined on sulfur-free or sulfur-corrected basis.
9. Precision and Bias
9.1 The following criteria should be used for judging the acceptability of estimated net heat of combustion results (95 % confidence):
9.1.1 Repeatability - The difference between successive results obtained by the same operator (using a second set of measured values for aromatics content, density, and distillation data) on identical test material would, in the long run, in the normal and correct use of the test method, exceed the following values (sulfur-free basis) in only one case in twenty.
Repeatability = 0.021 MJ/kg or [9 Btu/lb]
9.1.2 Reproducibility - The difference between two single and independent results obtained by different operators working in different laboratories on identical test material would, in the long run, exceed the following values in only one case in twenty.
Reproducibility = 0.046 MJ/kg or [20 Btu/lb]
NOTE 5 - The repeatability and reproducibility stated above is based on the summation of the repeatability and reproducibility of the test methods used in the calculations. It does not include the effect of the scatter of the original data about the regression line, described by Eq 1 and Eq 2. Therefore, the possibility that individual estimates may be in error in excess of the above precision should be recognized.
9.2 Bias - The correlation described by this test method is based on data obtained with methods equivalent to Test Method D4809 and the data scatter is described by Table 1. However, no statement on bias can be made because the bias for Test Method D4809 cannot be determined.
10. Keywords
10.1 aviation fuel; gross heat of combustion; heat energy; heat of combustion; heating tests; net heat of combustion
