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

2.2 Modeling Fuel Vaporization in a Fuel Tank
Numerous investigators have considered natural convection in enclosures, and examples
of reviews on the subject are in refs [30-32]. However, there are few available studies
treating the problem of simultaneous heat and mass transfer in enclosures. Reference
[23] used detailed numerical modeling of single component vaporization, and computed
the formation of flammable vapors in a vented cylindrical vessel. Fuel evaporation
within a vented fuel tank was considered in ref [6] using a film model for the
vaporization process and an equivalent single component fuel. A similar approach was
used in ref [29] for estimation of the fuel to air mass ratio in the tank. Stable and unstable
conditions in a tank ullage, the latter leading to free convective mixing, were discussed in
ref [33] using a test fuel tank with different wall and liquid heating combinations.
Equilibrium air to fuel ratios in a tank were estimated in ref [24] using the Peng-
Robinson equation of state and equivalent single and binary component fluids. Heating
and vaporization of liquid propane in a tank exposed to a fire, and the resulting explosion
hazard from the pressure buildup were discussed in ref [34], which includes several
citations on the subject.
The present model [11] employed the flow field that developed as a consequence
of natural convection between the heated tank floor and the unheated ceiling and
sidewalls. It included liquid vaporization of liquid on the test tank floor and
condensation on the tank walls and ceiling. For the relatively long test times in ref [2],
material and thermal transport within the test tank were considered quasi-steady, and the
fluids were assumed to be well mixed based on the magnitude of the gas and liquid phase
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