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

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±1°F. A Brisk Heat 2,160 watt silicone rubber heating blanket measuring 36” x 36” was mated to the bottom surface using RTV high temperature adhesive. An Omega Engineering CN616 series 6-channel temperature controller limited the blanket temperature. It had the capability to control the ramp up to a specified temperature and maintain that within a few degrees. Total hydrocarbon concentration within the ullage space was measured using a flame ionization detector (FID) hydrocarbon analyzer. A Model VE7 heated total hydrocarbon analyzer by J.U.M. engineering, shown in figure 3.3, was the analyzer used in the experiments. FID’s can detect the concentration of hydrocarbons in a sample by burning the sample in a hydrogen flame. When the sample is introduced into the hydrogen flame an ionization process is initiated that releases free ions. An electrostatic field is created by a high polarizing voltage applied to two electrodes near the burner. Positive ions collect at the high voltage electrode and negative ions migrate to the collector electrode. The current generated between the two electrodes is directly proportional to the amount of hydrocarbons in the sample, and provides accurate total hydrocarbon measurements in terms of a volumetric concentration relative to the calibration gas, in this case propane. The burner oven is heated to 374°F so that no condensation of fuel vapor occurs before reaching the flame. It is for this reason that heated sample lines and a sample pump with heated heads were required to draw the sample from the tank to the analyzer. Two Technical Heaters heated lines were used, 14’ and 4’, and maintained at 300°F by Technical Heaters temperature controllers. An Air Dimensions, Inc. Dia-Vac dual heated head pump was used to draw samples from sub-atmospheric pressures, as the FID’s built- in sample pump could not maintain the required sample pressure for tests at low ambient 21
pressures. The heaters in the pump heads were maintained at 300°F by the Omega 6- channel temperature controller. The FID required a 40% hydrogen / 60% helium fuel gas, and was calibrated with 2% propane in a nitrogen balance and checked for linearity with 4% propane in nitrogen, while hydrocarbon-free “zero” air or nitrogen was used to zero the analyzer. The output of the analyzer was in parts per million (ppm) propane equivalent on a scale of 0 to 100,000 corresponding to 0 to 10 volts DC output. The FID had the following measured characteristics: a response time of 0.2 seconds, a maximum sensitivity of 0.1 ppm CH4 in the lowest range, a zero and span drift of
Page 1 and 2: DOT/FAA/AR-TT09/42 Air Traffic Orga
Page 3 and 4: 1. Report No. DOT/FAA/AR-TT09/42 4.
Page 5 and 6: ABSTRACT OF THE THESIS VAPORIZATION
Page 7 and 8: DEDICATION This thesis is dedicated
Page 9 and 10: 5.0 RESULTS 32 5.1 Validation Tests
Page 11 and 12: 5.7 JP-8 fuel vaporization at sea l
Page 13 and 14: LIST OF TABLES Table Page 2.1 Compa
Page 15 and 16: develop procedures to lessen the li
Page 17 and 18: When it was determined that a CWT e
Page 19 and 20: 1.3 Objectives of the Thesis The ul
Page 21 and 22: has more additives, such as an anti
Page 23 and 24: equilibrium is dynamic in nature, b
Page 25 and 26: factor in making these calculations
Page 27 and 28: Volume Fraction, % 30 25 20 15 10 5
Page 29 and 30: 0.035±0.004 at 0°C [26]. The publ
Page 31 and 32: Raleigh numbers which were of order
Page 33: loading of fuel and be subjected to
Page 37 and 38: Figure 3.1. View of top surface of
Page 39 and 40: the tank and the ullage vapor conce
Page 41 and 42: attempted, but provided inaccurate
Page 43 and 44: pump that could draw samples from a
Page 45 and 46: 5.0 RESULTS When inputting the expe
Page 47 and 48: etween measured and predicted value
Page 49 and 50: 5.1.2 Isooctane Fuel Vaporization T
Page 51 and 52: higher altitudes, as continuous sam
Page 53 and 54: Temperature, Deg. F. 140 120 100 80
Page 55 and 56: Temperature, Deg. F. 70 60 50 40 30
Page 57 and 58: % Propane Equivalent 2 1.5 1 0.5 0
Page 59 and 60: % Propane Equivalent 3 2.5 2 1.5 1
Page 61 and 62: liquid fuel the mass of fuel evapor
Page 63 and 64: In the beginning of the test, the l
Page 65 and 66: 6.2 Flammability Assessment 6.2.1 F
Page 67 and 68: average measured liquid temperature
Page 69 and 70: Fuel to Air Mass Ratio 0.05 0.045 0
Page 71 and 72: 6.2.2 Fuel Tank Under Varying Ambie
Page 73 and 74: Fuel to Air Mass Ratio 0.045 0.04 0
Page 75 and 76: Fuel to Air Mass Ratio 0.05 0.04 0.
Page 77 and 78: temperature measurements would be r
Page 79 and 80: Which is appropriate for Raleigh nu
Page 81 and 82: d dt ( mg c pgTg ) = hb Ab ( Tb −
Page 83 and 84: APPENDIX C: EXPERIMENTAL FUEL FLASH
Page 85 and 86:
13. Fuel Flammability Task Group, A
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Vaporization of JP-8 Jet Fuel in a Simulated Aircraft Fuel Tank ...

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