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

loading of fuel and be subjected to varying fuel, surface, and ambient temperatures and
sub-atmospheric pressures. Temperature, pressure, and overall vapor concentration data
were recorded during experimentation and input into the computer model to compare the
predicted values with the experimentally obtained results.
The fuel tank, shown in figure 3.1, was constructed of ¼” aluminum metal sheets
welded together into a cube with outer dimensions 36” wide by 36” deep by 24” high.
Two access panels measuring 12” wide by 18” deep were located on the top surface to
allow for thermocouple pass-thru and ullage sampling. 2” and 3” diameter holes are also
located on the top surface, one for fuel fill and the other to allow for ullage venting
during ambient pressure changes. The tank was on a 2’ high stand to allow for the fuel to
drain out easily through a hole in the bottom surface. The tank was inside an
environmental chamber, shown in figure 3.2, with inner dimensions 6’ wide by 6’ high
by 8’ deep. The chamber had the capability of varying the temperature and pressure with
a cascade-type air conditioning unit that could drop the temperature as low as -100°F and
a vacuum pump that could drop the pressure as low as about 2 psia. Micristar-brand
temperature and pressure controllers located in the control booth had the capability to
program in test-specific profiles for the temporal temperature and pressure variations.
12 Omega Engineering K-type thermocouples were located in various places
throughout the tank and chamber; 8 were 1/16” flexible thermocouple probes and 4 were
surface mountable thermocouples to measure the tank surface temperatures. 4
thermocouples were located in the liquid fuel, one of which was used by the heater
temperature controller to maintain a specified liquid temperature, 3 more were located in
the ullage, and 1 was in the ambient chamber air. All thermocouples had an accuracy of
20