Vaporization of JP-8 Jet Fuel in a Simulated Aircraft Fuel Tank ...

the liquid fuel temperature by 5°F and 10°F resulted in significant broadening of the time
period when the ullage was flammable to also include part of the ascent to 30,000’.
Thus, the strong dependence of flammability on fuel temperature is again observed, as
the period of flammability is broadened as liquid temperature is increased.
The effect of mass loading on flammability is shown in figures 6.15 and 6.16.
Three different mass loadings were used in the model to calculate the FAR and LCR
using the input data from the same flight profile test. The test was conducted with a mass
loading of 31.5, while two other mass loadings, 300 kg/m 3 and 0.5 kg/m 3 , were also used
to calculate the respective FAR’s and LCR to investigate the effect mass loading has on
flammability. It can be seen that increasing the mass loading by about ten times barely
increases the flammability, but decreasing the mass loading down to 0.5 kg/m 3
significantly decreases the flammability down to the borderline of the LFL range. Again,
these results correlate well with the heated fuel tank at sea level and with previous
experimental work [2].
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