1. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D December 11th-12th, 2000 International Aircraft Systems Fire Protection Working Group NEA Ullage Washing Testing With a Vented Fuel Tank

2. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D Outline Background Ullage Washing Data Model Validation Hydrocarbon Effects Data Temperature Effects Data

3. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D Background Obtained Nitrogen Supply System from Air Liquide to Examine Fuel Tank Ullage Washing Utilized Existing Test Article Primary Task is to Characterize the Ability of Nitrogen to Inert an Empty Fuel Tank –Effective of Nitrogen Purity, Flow Rate –Effective Ullage Temperature / Hydrocarbon Concentration –Develop Empirical Relationships and Varify Existing Models

4. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D

5. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D

6. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D Nondimensional Time Want to Express Time in Terms of Volume Delivered Volumetric Tank Exchange = Time * Volume Flow Rate / Total Tank Volume Should Allow for Comparison of Data with Different Parameters, Regardless of Volume Flow Rate

7. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D

8. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D

9. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D Nondimensional Oxygen Concentration Want to Express [O 2 ] in Terms of Purity Delivered. Consider that Gas is Slowly Changing the Ullage to Gas Purity Tank Inertion Ratio = Air[O 2 ] - Tank[O 2 ] / Air[O 2 ] - NEA[O 2 ] Should Allow for Comparison of Data with Different Parameters, Regardless of Purity

10. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D

11. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D Comparison of Data with Solutions Empirical Equation (fourth order polynomial) Based on Previous Graph ANM-100 Model (Ivor Thomas) –Based on O 2 Volume Exchange –Gives One Nondimensional Solution Exact Solution Based on Perfect Mixing Model (y = 1 - e -λt ) Results Compare Well

12. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D

13. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D

14. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D Effects of Ullage Temperature / [THC] Performed Several Tests Varying Tank Ullage Temperature and Total Hydrocarbon Concentration Used Hot Plate Element, Kerosene Heater, and Liquid CO 2 Final Results Show Little Effect on Time to Inert

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16. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D

17. ________________________________________________________ Inerting System Testing AAR-422 Fire Safety R&D Future Work Continue with Re-circulate and Replace Work and Quantify Benefit Extrapolate Requirements for an On-Aircraft System and Determine Preliminary Cost/Ben Work with Manufacturers to Develop Innovative Designs to Cut Cost/Weight/Size