NIST Special Publication 1069

Richard G. Gann, Editor

Building and Fire Research Laboratory

The Final Report of the Next Generation 

Fire Suppression Technology Program

Advanced Technology for

Fire Suppression 

in Aircraft

U.S. Department of Commerce

Carlos M. Gutierrez, Secretary

Technology Administration

Robert C. Cresanti, Under Secretary for Technology

National Institute of Standards and Technology

William A. Jeffrey, Director

June 2007
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Certain commercial entities, equipment, or materials are identified in this 

document in order to describe an experimental procedure or concept

adequately. Such identification is not intended to imply recommendation or 

endorsement by the National Institute of Standards and Technology or the

Strategic Environmental Research and Development Program, nor is it 

intended to imply that the entities, materials, or equipment are necessarily 

the best available for the purpose. 

The policy of NIST is to use metric units of measurement in all its 

publications, and to provide statements of uncertainty for all original 

measurements. In this document, however, data from organizations

outside NIST are shown. These data may include measurements in nonmetric units or measurements without uncertainty statements.

National Institute of Standards and Technology Special Publication 1069 

Natl. Inst. Stand. Special Publication 1069, 1240 pages (June 2007) 

CODEN: NSPUE2 

U.S. GOVERNMENT PRINTING OFFICE 

WASHINGTON: 2007

For sale by the Superintendent of Documents, U.S. Government Printing Office 

Internet: bookstore.gpo.gov — Phone: (202) 512-1800 — Fax: (202) 512-2250 

Mail: Stop SSOP, Washington, DC 20402-0001 
ABSTRACT

Fires and explosions were, and continue to be, among the greatest threats to the safety of 

personnel and the survivability of military aircraft both in peacetime and during combat 

operations. Production of halon 1301 (CF3Br), long the fire suppressant of choice, ceased as of 

January 1, 1994 due to its high ozone depleting potential (ODP). By 1997, the U.S. Department 

of Defense (DoD) had identified the best available replacement for halon 1301 in aircraft, HFC125 (C2H5F), but it requires two to three times the mass and storage volume and contributes to 

global warming. Meanwhile, new aircraft were in various stages of design, and the international 

community was questioning the necessity of maintaining the large reserves of halon 1301. 

A new undertaking, the Next Generation Fire Suppression Technology Program (NGP), was 

created to identify, through research, fire suppression technologies with reduced compromises. 

Supported primarily by the DoD Strategic Environmental Research and Development Program 

(SERDP) as Project WP-1059, the NGP goal was to “Develop and demonstrate technology for 

economically feasible, environmentally acceptable and user-safe processes, techniques, and 

fluids that meet the operational requirements currently satisfied by halon 1301 systems in 

aircraft.” The multiple demands on the new technologies were daunting. 

In its decade of systematic research (1997-2006), the NGP revitalized the field of fire 

suppression science. This book tells the story of how the NGP came about, what research was 

performed, how it modernized the thinking in the field, and the technical findings that emerged 

related to fire suppression in aircraft. The enclosed CD compiles the collected publications from 

the program. 

Keywords: flame inhibition, fire research, fire suppression, halon, aircraft 
iv Abstract 

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TABLE OF CONTENTS

Abstract......................................................................................................................................................... i 

Table of Contents ........................................................................................................................................ v 

List of Figures.......................................................................................................................................... xvii 

List of Tables ............................................................................................................................................ xlv

Chapter 1: Introduction. .............................................................................................................................. 1 

1.1 Background....................................................................................................................1 

1.2 The Evolution of Fire Suppression ................................................................................1 

1.3 The Rise of Halons.........................................................................................................3 

1.4 The Atmospheric Threat ................................................................................................5 

1.5 History of the NGP ........................................................................................................9

1.6 This Book.....................................................................................................................15 

1.7 References....................................................................................................................16 

Chapter 2: History of Fire Suppression in Aircraft ................................................................................. 19 

2.1 Fire Threats to Military Aircraft ..................................................................................20 

2.2 Protected Compartments on Aircraft ...........................................................................24 

2.2.1 Engine Nacelles ...............................................................................................24 

2.2.2 Other Powerplant-type Compartments ............................................................28 

2.2.3 Dry Bay Compartments ...................................................................................31 

2.2.4 Cargo Compartments.......................................................................................34 

2.2.5 Other Compartments........................................................................................36 

2.2.6 Fuel Tank Ullage..............................................................................................37 

2.3 Types of Fires Experienced .........................................................................................41 

2.3.1 Safety-related Fires..........................................................................................43 

2.3.2 Ballistically-induced Fires...............................................................................45 
vi Table of Contents 

2.3.3 Spray Fires.......................................................................................................47 

2.3.4 Pool Fires.........................................................................................................49 

2.3.5 Fire Characteristics ..........................................................................................50 

2.3.6 Aircraft Operational Temperature Environment..............................................54 

2.3.7 Reignition.........................................................................................................79 

2.4 Fire Suppressants Used on Aircraft .............................................................................80 

2.4.1 Powerplant Compartments...............................................................................81 

2.4.2 Dry Bay Compartments ...................................................................................86 

2.4.3 Certification .....................................................................................................86 

2.5 Halon Alternative Technology Development Program (TDP)....................................92 

2.5.1 Phase 1 – Operational Parameters Study .........................................................93 

2.5.2 Phase 2 – Operational Comparison of Selected Extinguishants......................94 

2.5.3 Phase 3 – Establishment of Design Criteria Methodologies............................94 

2.5.4 Impact of Halon Alternative Fire Suppression to the Aircraft.........................96 

2.6 References..................................................................................................................109 

Chapter 3: Flame Suppression Chemistry ............................................................................................ 119 

3.1 Introduction................................................................................................................120 

3.2 Halogen-containing Compounds ...............................................................................121 

3.2.1 Previous Understanding of the Inhibition Mechanism of CF3Br...................121 

3.2.2 Suppression of Nonpremixed Flames by Fluorinated Ethanes and 

Propanes.........................................................................................................124 

3.3 Metal-containing Compounds....................................................................................142 

3.3.1 Background....................................................................................................142 

3.3.2 Metals with Demonstrated Flame Inhibition Potential ..................................155 

3.3.3 Flame Inhibition by Iron-containing Compounds..........................................156 

3.3.4 Flame Inhibition by Tin and Manganese .......................................................178 

3.3.5 Complexation/Matrix Absorption of Super-effective Agents........................199 

3.3.6 Potential for Loss of Effectiveness of Other Metals......................................224 

3.3.7 Flame Inhibition and Loss-of-effectiveness Summary..................................232 

3.3.8 Conclusions....................................................................................................235 
Table of Contents vii

3.4 Phosphorus.................................................................................................................236 

3.4.1 Introduction....................................................................................................236 

3.4.2 Inhibition of Non-premixed Flames by Phosphorus-containing 

Compounds ....................................................................................................238 

3.4.3 Effects of Dimethyl Methylphosphonate on Premixed Methane 

Flames............................................................................................................267 

3.4.4 Summary: Phosphorus-containing Compounds in Flames............................281 

3.5 Comparative Flame Inhibition Mechanisms of Candidate Moieties .........................282 

3.5.1 Introduction....................................................................................................282 

3.5.2 Spectroscopic Studies of Inhibited Opposed Flow Propane/Air 

Flames............................................................................................................282 

3.5.3 CF3Br and Other Suppressants: Differences in Effects on Flame 

Structure.........................................................................................................291 

3.5.4 Influence of Bond Energies on Catalytic Flame Inhibition ...........................299 

3.5.5 Temperature Regions of Optimal Chemical Inhibition of Premixed 

Flames............................................................................................................307 

3.6 Insights on Flame Inhibition ......................................................................................316 

3.7 References..................................................................................................................318 

Chapter 4: Aerosol Properties................................................................................................................ 339 

4.1 Introduction................................................................................................................340 

4.2 Previous Knowledge ..................................................................................................341 

4.2.1 Water..............................................................................................................341 

4.2.2 Powders..........................................................................................................341 

4.2.3 Combined Agents - Water Additives.............................................................342 

4.2.4 Burning Surfaces............................................................................................344 

4.2.5 Large-scale Studies ........................................................................................345 

4.2.6 Modeling........................................................................................................348 

4.3 The Nature of Aerosols..............................................................................................348 

4.3.1 Quantitative Descriptors ................................................................................348 

4.3.2 Generation Techniques ..................................................................................350 

4.3.3 Quantification of Aerosols.............................................................................351 

4.3.4 Aerosol Size and Velocity Characterization..................................................351 
viii Table of Contents 

4.3.5 Aerosol Properties Affecting Behavior..........................................................355 

4.4 The Nature of Flames.................................................................................................358 

4.4.1 Flame Characteristics.....................................................................................358 

4.4.2 Premixed Bunsen Type Flames .....................................................................359 

4.4.3 Non-premixed Flames....................................................................................360 

4.5 Aerosol Flame Suppression Studies...........................................................................363 

4.5.1 Water, a Physical Suppression Agent ............................................................363 

4.5.2 Alkali Metal Bicarbonates, Chemically Active Fire Suppressants................397 

4.5.3 Aqueous Metal Salt Solutions, Combined Chemical and Physical 

Suppression....................................................................................................412 

4.5.4 Dendrimers, Combined Chemical and Physical Flame Suppression.............430 

4.6 Surface Cooling .........................................................................................................438

4.6.1 Introduction....................................................................................................438 

4.6.2 Evaporation of Liquid Droplets.....................................................................440 

4.6.3 Spray Cooling ................................................................................................443 

4.6.4 Convective Regime........................................................................................444 

4.6.5 Nucleate Boiling Regime...............................................................................445 

4.6.6 Critical Heat Flux...........................................................................................446 

4.6.7 Transition and Film Boiling Regimes............................................................446 

4.6.8 Summary........................................................................................................448 

4.7 Aerosols and Burning Surfaces..................................................................................448 

4.7.1 Flame Spread Studies.....................................................................................449 

4.7.2 Droplet Interaction with a Hot Surface..........................................................458 

4.7.3 Summary and Conclusions ............................................................................466 

4.8 The New State of Knowledge of Flame Extinguishment by Aerosols......................467 

4.9 Relation of Findings to Practical Fires.......................................................................468 

4.10 References..................................................................................................................469 

Chapter 5: Instrumentation for Bench- and Large-scale Test Fixtures............................................... 481 

5.1 Introduction................................................................................................................482 

5.2 Laser Induced Breakdown Spectroscopy for Measurement of Fire 

Suppressants...............................................................................................................483 
Table of Contents ix

5.3 Tunable Diode Laser Absorption Spectroscopy (TDLAS) for 

Measurement of Combustion Products, Fuels, and Oxygen......................................485 

5.3.1 General...........................................................................................................485 

5.3.2 HF ..................................................................................................................486 

5.3.3 Oxygen...........................................................................................................490 

5.3.4 Fuels...............................................................................................................490 

5.3.5 Observations ..................................................................................................501 

5.4 Measurement of Fire Suppressant Concentration Using a Differential 

Infrared Rapid Agent Concentration Sensor (DIRRACS).........................................502 

5.4.1 Introduction....................................................................................................502 

5.4.2 Original Instrument Design – DIRRACS I....................................................502 

5.4.3 Improved Hardware Design – DIRRACS II..................................................505 

5.4.4 Data Acquisition and Analysis.......................................................................507 

5.4.5 Calibration Experiments ................................................................................507 

5.4.6 Release Tests of HFC-125 in the TARPF Facility.........................................508 

5.4.7 HFC-125 Release Tests in a Bradley Vehicle................................................509 

5.4.8 Assessment.....................................................................................................513 

5.5 Conclusion .................................................................................................................513 

5.6 References..................................................................................................................514 

Chapter 6: Screening Tests for Candidate Fire Suppressants ............................................................ 517 

6.1 The Need for Screening Tests....................................................................................518 

6.2 General Approach ......................................................................................................519 

6.3 Agent Properties to be Screened................................................................................519 

6.4 Fire Suppression Efficiency Screening......................................................................521 

6.4.1 Estimation of Values......................................................................................521 

6.4.2 Cup Burner.....................................................................................................522 

6.4.3 Dispersed Liquid Agent Fire Suppression Screen (DLAFSS).......................525 

6.4.4 Transient Application, Recirculating Pool Fire Apparatus (TARPF)............535 

6.4.5 Summation .....................................................................................................557 

6.5 Atmospheric Lifetime Screen ....................................................................................557 

6.5.1 Factors Affecting Atmospheric Harm............................................................557 
x Table of Contents 

6.5.2 Prior Estimation Methods..............................................................................558 

6.5.3 The Screening Protocol..................................................................................561 

6.5.4 Removal by Hydroxyl Radical Reaction .......................................................561 

6.5.5 Measurement of Photolysis Rates..................................................................565 

6.5.6 Estimation of Reactivity ................................................................................568 

6.5.7 Solution of Fluoroalkylamines.......................................................................571 

6.5.8 Reactivity of Alkyl Phosphates towards Radicals in Water ..........................571 

6.6 Volatility Screen ........................................................................................................572 

6.6.1 Extinguishant Volatility.................................................................................572 

6.6.2 Extinguishant Evaporation Equilibrium ........................................................572 

6.6.3 Extinguishant Evaporation Rate ....................................................................574 

6.6.4 Boiling Temperature ......................................................................................576 

6.7 Toxicity Screen ..........................................................................................................577 

6.7.1 Hazards and Regulation .................................................................................577 

6.7.2 Screening Process..........................................................................................578 

6.7.3 Literature Values............................................................................................579 

6.7.4 Quantitative Structure Activity Relationships...............................................581 

6.7.5 Non-animal Laboratory Testing.....................................................................584 

6.7.6 In vitro Tests..................................................................................................589 

6.7.7 PBPK Modeling of Cardiotoxic Effects ........................................................590 

6.7.8 Limit Tests.....................................................................................................596 

6.8 Application of Screen Tests.......................................................................................597 

6.9 References..................................................................................................................598 

Chapter 7: Search for New Fire Suppressant Chemicals..................................................................... 611 

7.1 Fire Suppressant Replacement Knowledge prior to the NGP....................................612 

7.1.1 Overview of Early Halon Replacement Efforts.............................................612 

7.1.2 Fire Suppressant Research - 1974 through 1993 ...........................................613 

7.1.3 DoD Technology Development Plan (1993 through 1997)...........................615 

7.1.4 Advanced Agent Working Group (AAWG)..................................................616 

7.1.5 Summary: Alternative Agents and Selection Criteria prior to the 

NGP................................................................................................................622 
Table of Contents xi

7.2 The NGP Approach to New Chemicals Screening....................................................623 

7.3 NGP Surveys of Inorganic Chemical Families..........................................................626 

7.3.1 Main Group Elements - Group I ....................................................................626 

7.3.2 Main Group Elements - Group II...................................................................627 

7.3.3 Main Group Elements - Group III .................................................................627 

7.3.4 Main Group Elements - Group IV .................................................................628 

7.3.5 Main Group Elements - Group V...................................................................634 

7.3.6 Main Group Elements - Group VI .................................................................645 

7.3.7 Main Group Elements - Group VIII...............................................................646 

7.3.8 Transition Metal-based Compounds..............................................................646 

7.3.9 Inorganic Chemicals - Conclusions ...............................................................647 

7.4 NGP Surveys of Organic Compounds .......................................................................647 

7.4.1 Highly Efficient Thermal Agents...................................................................647 

7.4.2 Tropodegradable Candidate Compounds.......................................................658 

7.4.3 Bromofluoroalkenes.......................................................................................662 

7.4.4 Fluoroalkoxide and Fluoroalkyl Phosphorus Compounds.............................665 

7.4.5 Fluoroalkyl Nitrogen-based Candidates ........................................................680 

7.4.6 Bromofluoroalkyl Nitrogen-based Candidates ..............................................685 

7.4.7 Fluorinated Ethers..........................................................................................687 

7.4.8 Bromofluoroethers .........................................................................................691 

7.4.9 Bromofluorooxiranes .....................................................................................694 

7.4.10 Bromofluoro/Fluorinated Aldehydes and Ketones ........................................695 

7.4.11 Bromofluoro Alcohols ...................................................................................695 

7.4.12 Iodinated Hydrocarbons.................................................................................696 

7.5 Chemical Family Options and Replacement Issues...................................................700 

7.5.1 Suppressant Criteria and Selection Constraints .............................................700 

7.5.2 General Conclusions ......................................................................................701 

7.6 References..................................................................................................................702 

Chapter 8: Fluid Dispensing and Dispersion ........................................................................................ 721 

8.1 Introduction................................................................................................................722 

8.1.1 Characteristics of Aircraft Engine Nacelle Fires ...........................................722 
xii Table of Contents 

8.1.2 Summary of Suppressant Fluid Dynamics.....................................................723 

8.1.3 Scope..............................................................................................................724 

8.2 Fluid Storage..............................................................................................................725 

8.3 Fluid Transport through Piping..................................................................................726 

8.3.1 Introduction....................................................................................................726 

8.3.2 Previous Work ...............................................................................................728 

8.3.3 Base Code Selection ......................................................................................730 

8.3.4 Code Development Work ..............................................................................732 

8.3.5 Code Theory...................................................................................................733 

8.3.6 Supporting Laboratory Data ..........................................................................753 

8.3.7 Comparison of Code Predictions to Experimental Data ................................786 

8.3.8 Assessment of Fluid Transport Model...........................................................804 

8.4 Dynamics of Fluid Transport in Cluttered Spaces.....................................................805 

8.4.1 Spray Transport past Generic Clutter Elements.............................................805 

8.4.2 Spray Interaction with Unheated and Heated Clutter Elements ....................809 

8.4.3 Transport around Clutter and Recirculation Zones........................................821 

8.4.4 Low Temperature Effects on Agent Dispersion ............................................829 

8.5 Modeling of Fluid Dispersion in a Nacelle................................................................839 

8.5.1 Background....................................................................................................839 

8.5.2 CFD Models...................................................................................................839 

8.5.3 Code Assessment Using Quarter-Scale Nacelle Tests and 

Simulations ....................................................................................................847 

8.5.4 Assessment of VULCAN Fire Suppression Sub-model ................................854 

8.5.5 Assessment of VULCAN in Suppressant Distribution in a Fullscale Nacelle ..................................................................................................863 

8.5.6 Assessment of VULCAN in Pool Fire Suppression in a Full-scale 

Nacelle ...........................................................................................................868 

8.6 Full-scale Nacelle Fire Suppression Tests.................................................................871 

8.6.1 Experimental Design......................................................................................871 

8.6.2 Test Facility ...................................................................................................872 

8.6.3 Test Matrices and Decision Tree ...................................................................876 

8.6.4 Actual Test Program ......................................................................................878 

8.6.5 Instrumentation ..............................................................................................879 
Table of Contents xiii

8.6.6 Test Procedure ...............................................................................................879 

8.6.7 Test Results and Comparisons to Simulations...............................................882 

8.7 Improved Transport of Water to Fires .......................................................................889 

8.7.1 Background....................................................................................................889 

8.7.2 Electrically Charged Water Mist ...................................................................889 

8.7.3 A Self-atomizing Form of Water ...................................................................909 

8.8 Summary of Lessons Learned....................................................................................916 

8.9 References..................................................................................................................918 

Chapter 9: Powder Panel and Propellant Discharge Technologies .................................................... 927 

9.1 Introduction................................................................................................................927 

9.2 Enhanced Powder Panels ...........................................................................................929 

9.2.1 NGP Objectives .............................................................................................929 

9.2.2 Background on Powder Panel Technology....................................................930 

9.2.3 Operating Principle ........................................................................................931 

9.2.4 Technical Issues.............................................................................................933 

9.2.5 Survey of Powder Panel Applications ...........................................................934 

9.2.6 Powder Dispersion Screening Experiments...................................................937 

9.2.7 Live-fire Proof-of-concept Demonstrations...................................................947 

9.2.8 Optimization Program....................................................................................951 

9.2.9 Live-fire Demonstration Testing of Optimized Enhanced Powder 

Panels .............................................................................................................957 

9.2.10 Mass-trade Comparison Analysis ..................................................................970 

9.2.11 Summary of Powder Panel Research Program ..............................................974 

9.3 Solid Propellant Gas Generators................................................................................976 

9.3.1 Brief History ..................................................................................................976 

9.3.2 Operating Principles.......................................................................................977 

9.3.3 Experimental Techniques...............................................................................978 

9.3.4 Results: General Behavior of Propellants......................................................990 

9.3.5 Results: Cooled Propellant Formulations ......................................................994 

9.3.6 Results: Chemically Active Fire Suppressants ............................................1003 

9.3.7 Results: Hybrid Fire Extinguishers..............................................................1013 
xiv Table of Contents 

9.3.8 Summary of Solid Propellant Gas Generator Research...............................1020 

9.4 References................................................................................................................1023 

Chapter 10: Life Cycle Costing of Fire Suppression Systems........................................................... 1025 

10.1 Background..............................................................................................................1025 

10.1.1 Technical Concept .......................................................................................1025 

10.1.2 NGP Tasks...................................................................................................1026 

10.1.3 General Methodology ..................................................................................1027 

10.2 Agent Properties.......................................................................................................1027 

10.3 Current System Description (Halon 1301) for Legacy Aircraft ..............................1028 

10.3.1 Cargo Aircraft ..............................................................................................1028 

10.3.2 Fighter Aircraft ............................................................................................1034 

10.3.3 Rotary-wing Aircraft....................................................................................1038 

10.4 Proposed System Description (HFC-125) for Future Aircraft.................................1042 

10.4.1 Design Guide ...............................................................................................1042 

10.4.2 Cargo Aircraft ..............................................................................................1045 

10.4.3 Fighter Aircraft ............................................................................................1048 

10.4.4 Rotary-wing Aircraft....................................................................................1052 

10.5 Costs of Current and Replacement Systems............................................................1054 

10.5.1 Life-Cycle Cost Estimate (LCCE) Summary for Legacy Aircraft ..............1056 

10.5.2 Life-Cycle Cost Estimate (LCCE) Summary for Future Aircraft................1058 

10.5.3 Detailed Cost Element Structure (CES).......................................................1061 

10.5.4 Cost Element Structure Data Development .................................................1061 

10.6 Cost Savings.............................................................................................................1066 

10.7 Cost Analysis Using Altered Fire Suppression Performance ..................................1068 

10.7.1 Factor of Safety Testing...............................................................................1068 

10.7.2 System Description ......................................................................................1069 

10.7.3 Altered Fire Suppression Performance ........................................................1070 

10.7.4 Cost Analysis...............................................................................................1073 

10.8 Conclusions..............................................................................................................1082 

10.9 References................................................................................................................1083 
Table of Contents xv

Chapter 11: Verification of Fire Suppression Principles.................................................................... 1087

11.1 Context.....................................................................................................................1088 

11.2 Complexity of In-flight Fires and Their Suppression..............................................1088 

11.3 New Understanding of the Fire Suppression Process..............................................1090 

11.3.1 Overview of Fire Suppression .....................................................................1090 

11.3.2 Control of the Air Supply to the Fire...........................................................1090 

11.3.3 Delivery of the Fire Suppressant to the Fire ................................................1090 

11.3.4 Effectiveness of a Fire Suppressant at Quenching Flames ..........................1094 

11.4 Evaluation of Candidate Fire Suppressant Technologies ........................................1098 

11.4.1 Screening Measures .....................................................................................1098 

11.4.2 Measurements during Fire Tests..................................................................1100 

11.4.3 Life-cycle Cost Assessment.........................................................................1101 

11.5 Potential for New, Viable Suppressants...................................................................1101 

11.6 Fire Suppression Principles to be Tested.................................................................1103 

11.7 Methodology for Real-scale Testing and Validation...............................................1106 

11.7.1 Aircraft Engine Nacelle Test Facility Features and Capabilities.................1106 

11.7.2 Design of Experiments Methodology ..........................................................1112 

11.7.3 “Bracketing” Procedure for Testing.............................................................1115 

11.7.4 Experimental Approach, Configuration and Procedure...............................1115 

11.8 Results and Analysis................................................................................................1125 

11.8.1 Summary of General Data Collected ...........................................................1125 

11.8.2 Principle 1 ....................................................................................................1126 

11.8.3 Principle 3 ....................................................................................................1127 

11.8.4 Principle 5 ....................................................................................................1128 

11.8.5 Principle 6 ....................................................................................................1128 

11.8.6 Principle 7 ....................................................................................................1129 

11.8.7 Extinguishing Mixing Models .....................................................................1130 

11.8.8 Principle 4 ....................................................................................................1134 

11.8.9 Principle 2 ....................................................................................................1137 

11.8.10 Phase III Results..........................................................................................1141 

11.9 Summary..................................................................................................................1141 
xvi Table of Contents 

11.10 References................................................................................................................1143 

Chapter 12: Afterword........................................................................................................................... 1145 

12.1 A View Ahead..........................................................................................................1145

12.2 References................................................................................................................1148 

Appendix A: Acknowledgements......................................................................................................... 1149 

Appendix B: NGP Projects.................................................................................................................... 1151 

Appendix C: NGP Publications............................................................................................................. 1155 

Index ....................................................................................................................................................... 1175 
LIST OF FIGURES

Figure 1–1. Interior of an Aircraft Engine Nacelle..................................................................................... 11 

Figure 1–2. Projects Contributing to Deliverable 1: Best Alternative Suppressant Chemicals. ................. 13 

Figure 1–3. Projects Contributing to Deliverable 2: Guidelines for Optimal Application of 

Extinguishants................................................................................................................................ 14 

Figure 1–4. Projects Contributing to Deliverable 3: Alternative Extinguishment Technologies. .............. 14 

Figure 1–5. Projects Contributing to Deliverable 4: Technology Options Assessment 

Protocol.......................................................................................................................................... 15 

Figure 2–1. Significant Non-combat Fire Locations on U.S. Navy Aircraft 1977-1993............................ 21 

Figure 2–2. Combustion Threats in and around an Aircraft Fuel Tank. ..................................................... 21 

Figure 2–3. Illustration of Notional Reduction in Overall Rotorcraft Vulnerable Area. ............................ 22 

Figure 2–4. Known Ejection Locations of Navy Aircrewmen Who Became POWs during the 

Southeast Asia Conflict.................................................................................................................. 23 

Figure 2–5. Locations of Navy Rescues of Navy Aircrewmen during the Southeast 

Asia Conflict. ................................................................................................................................. 23 

Figure 2–6. Example Turboshaft Engine. ................................................................................................... 25 

Figure 2–7. A Fighter Aircraft Engine Nacelle........................................................................................... 26 

Figure 2–8. Diagram of an Aircraft Fire Suppression System Installation................................................. 26 

Figure 2–9. An Aircraft Engine Nacelle Fire Suppression System Installation, Suppressant 

Bottle External to the Nacelle. ....................................................................................................... 27 

Figure 2–10. An Aircraft Engine Nacelle Fire Suppression System Installation, Suppressant 

Bottle Within the Nacelle............................................................................................................... 28 

Figure 2–11. A Transport Aircraft Auxiliary Power Unit Installation........................................................ 29 

Figure 2–12. A Fighter Aircraft Accessory Compartment With Fire Suppression System

Installation ..................................................................................................................................... 30 

Figure 2–13. An Aircraft Gearbox Compartment with APU...................................................................... 30 

Figure 2–14. A Secondary Power System (SPS) Installation. .................................................................... 31

Figure 2–15. Typical Dry Bay Locations in a Fighter Aircraft................................................................... 32 

Figure 2–16. A Dry Bay Compartment Adjacent to a Fuel Tank; Fire Detector and Fire 

Suppressor Installed within the Dry Bay Compartment. ............................................................... 32 

Figure 2–17. Top View of a Wing Dry Bay Containing Drive, Hydraulic, and Electrical 

Systems Components..................................................................................................................... 33 

Figure 2–18. A Wing Leading Edge Dry Bay Containing Hydraulic and Electrical Systems 

Components, Leading Edge Structure Removed. .......................................................................... 33 
xviii List of Figures 

Figure 2–19. Non-DoD Aircraft Halon 1301 Dry Bay Fire Protection System.......................................... 35 

Figure 2–20. Diagram of a Cargo Fire Suppression System Installation on a Transport 

Aircraft........................................................................................................................................... 36 

Figure 2–21. Illustration of Ullage Fire/Explosion Protection Devices...................................................... 38 

Figure 2–22. F-16 Aircraft Inerting System Diagram................................................................................. 40 

Figure 2–23. Imperial Japanese Navy Dry Bay and Ullage Fire Suppression System Concept, 

Late World War II.......................................................................................................................... 46 

Figure 2–24. Ignition and growth of a flame in 7 % H2, 1.4 % C3H8 Jet A Simulant Mixture at 

295 K and 84.1 kPa........................................................................................................................ 47 

Figure 2–25. Spark-Initiated Ullage Combustion Process.......................................................................... 48 

Figure 2–26. Stabilized Pool Fire Formation within an Aircraft Dry Bay Compartment........................... 49 

Figure 2–27. Flame Temperature vs. Equivalence Ratio............................................................................ 50 

Figure 2–28. Hydrocarbon Flame Emission Spectra. ................................................................................. 52 

Figure 2–29. Turbulent Fire within Aircraft Dry Bay Compartments. ....................................................... 53 

Figure 2–30. Variation in Halon 1301 Peak Flammability Limits for Isobutane with 

Temperature. .................................................................................................................................. 54 

Figure 2–31 Variation in Halon 1301 and Three Halon Alternative Mass Fractions (Beta) 

Required to Suppress JP-8 Spray Flames with Temperature......................................................... 55 

Figure 2–32. Commercial Aviation Standard Climates vs. DoD WWAE Design Guidance. .................... 56 

Figure 2–33. DoD Land Environment Design Guidance............................................................................ 57

Figure 2–34 Variation of Ambient Pressure vs. Pressure and Geopotential Altitudes on 

Standard-day and Non-standard-day Temperature Conditions...................................................... 61 

Figure 2–35. Flammability Limits of Jet-A and Jet-B Fuels vs. Altitude and Standard 

Atmospheres. ................................................................................................................................. 62 

Figure 2–36. Plot of Standard Climate Profiles and WWAEs vs. All DoD Aircraft Fire Events 

and Suppressant Releases where Both Altitude and OAT Were Provided.................................... 63 

Figure 2–37. Plot of 1988-2000 Commercial Aircraft Fire Events vs. Altitude and OAT, 

Events for which NTSB Database Provided Both Altitude and OAT. .......................................... 64 

Figure 2–38. Rotary Aircraft Nacelle/APU Compartment Fire Suppressant Releases by

Altitude. ......................................................................................................................................... 64 

Figure 2–39. Rotary Aircraft Nacelle/APU Compartment Fire Suppressant Releases by OAT................. 65 

Figure 2–40. Fixed-wing Aircraft Nacelle/APU Compartment Fire Suppressant Releases by

Altitude. ......................................................................................................................................... 65 

Figure 2–41. Fixed-wing Aircraft Nacelle/APU Compartment Fire Suppressant Releases by

OAT. .............................................................................................................................................. 65 

Figure 2–42. Peak Nacelle Temperature at 50 knots Airspeed vs. Altitude. .............................................. 67 

Figure 2–43. Peak Nacelle Temperature at 400 knots Airspeed vs. Altitude. ............................................ 67 

Figure 2–44. Initial OAT per JAR-1 Arctic Standard Climate. .................................................................. 71
List of Figures xix

Figure 2–45. OAT at Takeoff is -40 °C (-40 °F) with Bias Applied to OAT. ............................................ 71 

Figure 2–46. Fixed-Wing Aircraft Fire Mishaps and Incidents by Phase of Operation. ............................ 74 

Figure 2–47. Distribution of DoD Rotary Aircraft Ground Fire Locations................................................ 75 

Figure 2–48. Distribution of DoD Fixed-Wing Aircraft Ground Fire Locations........................................ 75 

Figure 2–49. Distribution of DoD In-Flight Rotary Aircraft Fire Locations.............................................. 76 

Figure 2–50. Distribution of DoD In-Flight Fixed-Wing Aircraft Fire Locations...................................... 76 

Figure 2–51. DoD Rotary Aircraft Fire Data vs. Atmospheric Profiles, Flammability Limit 

Profiles, Operational Ceiling, and Suppressant Release. ............................................................... 77 

Figure 2–52 DoD Fixed-Wing Aircraft Fire Data vs. Atmospheric Profiles, Flammability 

Limit Profiles, Potential Stall Condition and Suppressant Release. .............................................. 78 

Figure 2–53. Example Conventional Halon 1001 Powerplant Fire Suppression System 

Distribution Installation, USN Turboprop Powerplant. ................................................................. 82 

Figure 2–54. Example Conventional Halon 1011 Fire Extinguishing System Distribution 

Installation, Turboprop Powerplant. .............................................................................................. 83 

Figure 2–55. Example Conventional Halon 1011 Fire Extinguishing System Distribution 

Installation, USAF Turbojet Powerplant. ...................................................................................... 84

Figure 2–56. Minimum Discharge Duration from an HRD System Using Halon 1011............................. 85 

Figure 2–57. Zones Protected by the Nitrogen Fire Suppression System on C-5 Aircraft. ........................ 89 

Figure 2–58. Fire Suppressant Concentration Analyzer Sampling Probe Installation................................ 90 

Figure 2–59. Example Fire Suppression System Suppressant Concentration Measurement...................... 90 

Figure 2–60. MIL-HDBK-221 Design Guidance for Explosion Suppression............................................ 91 

Figure 2–61. Typical Legacy OBIGGS Qualification Test Oxygen Concentration 

Measurement Location................................................................................................................... 92 

Figure 2–62. Comparison of Halon 1301 Certification Requirement and HFC-125 Design 

Equation Limits vs. Published Flammability Limits. .................................................................... 97 

Figure 2–63. Example of Non-optimized Halon 1301 Nacelle Concentration Distribution....................... 98 

Figure 2–64. Example of Non-optimized HFC-125 Nacelle Concentration Distribution. ......................... 98 

Figure 2–65. Examples of HFC-125 Nacelle Concentrations................................................................... 100 

Figure 2–66. Summary of HFC-125 and SPGG Fire Suppression Results from C-130J Live 

Fire Testing. ................................................................................................................................. 103 

Figure 2–67. Time Sequence of Dry Bay Compartment Fire Suppression by Inert Gas 

Generators.................................................................................................................................... 104 

Figure 2–68. V-22 Inert Gas Generator Fire Suppression System............................................................ 104 

Figure 2–69 NGP Testing Results Comparing Solid Propellant Inert Gas Generator Propellant 

Mass vs. Chemically Active Gas Generator Propellant Mass...................................................... 105 

Figure 2–70. Effect of Suppressant Concentration and Mass Fraction on Peak Explosive 

Pressure for LFEs Pressurized to 1,000 psi, 12.7 mm API Threat and 3 % JP-4S. ..................... 107 
xx List of Figures 

Figure 3–1. Comparison of Local Strain Rates Measured by Laser Doppler Velocimetry in 

Non-premixed Counterflow Flames and Calculated Global Strain Rates.................................... 129 

Figure 3–2. Extinction Strain Rate vs. Agent Molar Concentration for Non-premixed 

Methane-air Flames Suppressed by: a) Fluorinated Ethanes, SF6, and N2; and b) 

Fluorinated Propanes. .................................................................................................................. 130 

Figure 3–3. Extinction Strain Rate vs. Agent Molar Concentration for Non-premixed 

Propane-air Flames Suppressed by: a) Fluorinated Ethanes, SF6, and N2; b)

Fluorinated Propanes; and c) Bromine- or Iodine-containing Methanes. .................................... 131 

Figure 3–4. Reaction Pathways for Premixed Methane/air Flames Doped with 3.81 Volume 

% of: (a) HFC-134 and (b) HFC-134a......................................................................................... 136 

Figure 3–5. Extinction Concentrations for Agents Suppressing: (a) n-heptane/air Cup Burner

Flames; (b) Methanol/air Cup Burner Flames; (c) Methane/air Counterflow Flames at 

a Strain Rate of 80 s-1; (d) Propane/air Counterflow Flames at a Strain Rate of 80 s

-1................ 139 

Figure 3–6. Effect of Fuel Type on Agent Extinction Concentration....................................................... 141 

Figure 3–7. Mole Merit Number of Metal-containing Compounds for the Oxidizer Velocities 

in the Range of 50 cm/s to 60 cm/s.............................................................................................. 147 

Figure 3–8. Main Catalytic Radical Recombination Cycle of Iron Found to be Important for 

Methane-air Flames. .................................................................................................................... 156 

Figure 3–9. Radical Recombination Reaction Pathways Found to be Important for CO-H2-O2-

N2 Flames..................................................................................................................................... 157 

Figure 3–10. Different Classes of Reactions Which May Contribute to Iron's Super-efficient 

Flame Suppression Ability through the Catalytic Recombination of Radical Species. ............... 158 

Figure 3–11. Calculated H-atom Super-equilibrium Ratio and Peak Temperature in a 

Counterflow Diffusion Flame as a Function of Strain Rate......................................................... 158 

Figure 3–12. Schematic Diagram of the Low Pressure Burner and Optical Measurement

Arrangement. ............................................................................................................................... 160 

Figure 3–13. Emission Image Collected from the Centerline of the Low Pressure, Opposed 

Flow, CH4-air flame with 10 % of the Fe(CO)5 Concentration Required to Extinguish 

the Flame...................................................................................................................................... 163 

Figure 3–14 LIF [OH] Profiles Collected from Inhibited CH4-air Flames Containing 

Nominally Half of the Concentration Required for Extinguishment. .......................................... 163 

Figure 3–15. Dependence of Normalized Maximum OH LIF Intensity on Inhibitor 

Concentration............................................................................................................................... 165 

Figure 3–16. Calculated and Measured Normalized Burning Velocity of Premixed CH4/O2/N2

Flames.......................................................................................................................................... 167 

Figure 3–17. Normalized Burning Velocity and Maximum Measured Scattering Signal Qw for

φ=1.0 CH4 Flame with XO2,ox = 0.21 and 0.24............................................................................. 168 

Figure 3–18. Maximum Scattering Signal and Normalized Burning Velocity for 

CO-H2 Flames as Fe(CO)5 Concentration Varies. ....................................................................... 168 

Figure 3–19. Maximum Qvv for Flames of CH4 and CO as a Function of Burning Velocity. .................. 169 
List of Figures xxi

Figure 3–20. Calculated Normalized Burning Velocity for Several Diameters of Ideal 

Heterogeneous Inhibitor, Fe(CO)5 data, and Calculated Normalized Burning Velocity 

using the Perfect Gas Phase Inhibitor Mechanism....................................................................... 169 

Figure 3–21. Normalized Extinction Strain Rate for Counterflow Diffusion Flames. ............................. 170 

Figure 3–22. Correlation between Inhibition Effect in Counterflow Diffusion Flames and 

Maximum Measured Scattering Signal Qvv . ............................................................................... 171 

Figure 3–23. Volume Fraction of CO2 Required for Extinction (XCO2,ext) of Methane-air Cup 

Burner Flames as a Function of the Volume Fraction of Catalytic Inhibitor Added to 

the Air Stream.............................................................................................................................. 172 

Figure 3–24. Particle Light Scattering as a Function of Radial Position and Height above Cup 

Burner for Four Loadings of Fe(CO)5.......................................................................................... 173 

Figure 3–25. Calculated Temperature and Velocity Vectors for Methane-air Cup Burner 

Flame with an Oxidizer Stream CO2 Volume Fraction of 0.1, with and without an 

Added Fe(CO)5 Volume Fraction of 100 μL/L. ........................................................................... 174 

Figure 3–26. Map of Calculated Temperatures in Cup Burner Methane-air Flames with 10 % 

CO2 in the Oxidizer Stream and (a) 0.011 and (b) 0.012 Fe(CO)5 Volume Fraction in 

the Air Stream, Illustrating the Blowoff Phenomenon. ............................................................... 174 

Figure 3–27. Experimental and Calculated Extinction Volume Fraction of CO2 and Peak 

Measured Scattering Cross Section as a Function of the Volume Fraction of Fe(CO)5

in the Air Stream.......................................................................................................................... 175 

Figure 3–28. (a) Calculated Volume Fractions, Xi, of Iron-containing and Other Major 

Species as a Function of Radial Position at 4.8 mm above the burner (corresponding 

to the location of the reaction kernel in the flame base); and (b) the Supersaturation 

Ratio, Si, for Fe, FeO, and Fe(OH)2............................................................................................. 176 

Figure 3–29. Calculated Particle Trajectories for Free Molecular Regime Particles in a CH4–

air Flame with 10 % CO2 in the Oxidizer Stream........................................................................ 177 

Figure 3–30. Visible Images of Methane-air Premixed Flames. .............................................................. 186 

Figure 3–31. Normalized Burning Velocity of Premixed CH4/O2/N2 Flames Inhibited by 

TMT for XO2,ox=0.21 and φ=0.9, 1.0, and 1.1.............................................................................. 187 

Figure 3–32 – Normalized Burning Velocity of Premixed CH4/O2/N2 flames Inhibited by 

TMT for φ=1.0 and XO2,ox=0.20, 0.21, and 0.244........................................................................ 188 

Figure 3–33. Normalized Burning Velocity of Premixed CH4/O2/N2 Flames Inhibited by 

MMT with XO2,ox=0.21 and φ=0.9, 1.0, and 1.1. ......................................................................... 189 

Figure 3–34. Normalized Burning Velocity of Premixed CH4/O2/N2 Flames Inhibited by 

MMT, with φ=1.0 and XO2,ox=0.19, 0.20. 0.21, and 0.244. ......................................................... 189 

Figure 3–35. Normalized Burning Velocity of Premixed CH4/O2/N2 Flames Inhibited by CO2, 

CF3Br, Sn(CH3)4, SnCl4, MMT, and Fe(CO)5. Tin = 353 K for all data except 

Sn(CH3)4 and SnCl4 which are at 298 K.. .................................................................................... 190 

Figure 3–36. Normalized Burning Velocity of Premixed CH4/O2/N2 Flames Inhibited by Pure 

MMT and Fe(CO)5, and by a Blend of the Two. ......................................................................... 191 

Figure 3–37. Reaction Pathways for Sn, Mn, and Fe in a Premixed Methane-air Flame 

(φ=1.0, XO2,ox =0.21, Tin=353 K).................................................................................................. 192 
xxii List of Figures 

Figure 3–38. First-order Sensitivity Coefficient of the Burning Velocity to the Specific

Reaction Rate Constant for Reactions with Tin-containing Species (1963 μL/L of 

TMT)............................................................................................................................................ 194 

Figure 3–39. First-order Sensitivity Coefficient of the Burning Velocity to the Specific

Reaction Rate Constant for Reactions with Manganese-containing Species (150 μL/L

of MMT). ..................................................................................................................................... 195 

Figure 3–40. Volume Fractions of O, and OH Radicals and Metal Species Intermediates as a

Function of Temperature in Flame for Fe(CO)5, MMT, and TMT 197 

Figure 3–41 Fractions of Sn-, Mn-, and Fe-species at Equilibrium in Methane-air Flames as a 

Function of Temperature.............................................................................................................. 198 

Figure 3–42. Schematic of the Experimental Setup for Fe(CO)5 Absorption........................................... 201 

Figure 3–43. High Resolution Transmission Electron Micrograph Images of Zeolite-NaX

Particles........................................................................................................................................ 204 

Figure 3–44. Schematic Diagram of Counterflow Diffusion Flame Burner with Provision for

Addition of Particles to the Air Stream........................................................................................ 206 

Figure 3–45. Calculated and LDV-measured Velocity Profiles at Exit of Premixed Burner

Nozzle for Total Flows of 7.4 and 9 L/min.................................................................................. 207 

Figure 3–46. Methane-air Counterflow Diffusion Flames: Pure and with NaHCO3 Particles ................. 208 

Figure 3–47. NaHCO3 and Silica Mass Fraction vs. Methane-air Nonpremixed Extinction

Strain Rate.................................................................................................................................... 208 

Figure 3–48 – Laser Scattering of NaHCO3 Particles in a Counterflow Diffusion Flame of

Methane and Air, Showing that the Particles Pass Through the Flame. ...................................... 209 

Figure 3–49. Premixed Methane-air Nozzle Burner Flames: Pure and with NaHCO3 Particles.............. 210 

Figure 3–50. Comparison of Normalized Burning Velocities with Added Particles................................ 210 

Figure 3–51. Normalized Flame Strength as a Function of Added NaHCO3 Mass Fraction for 

Premixed and Counterflow Diffusion Flames. ............................................................................ 211 

Figure 3–52. Normalized Flame Speed for a Methane-air Flame with Added Silica Gel

Particles (14 to 40) μm, with and without I2 Impregnated in the Particles. ................................. 212 

Figure 3–53. Normalized Burning Velocity of Premixed CH4/O2/N2 Flames Inhibited by

Ferrocene and Fe(CO)5, Together with Modeling Predictions (dotted lines). ............................. 216 

Figure 3–54. Normalized Burning Velocity of Stoichiometric CH4-O2-N2 Flames at 400 μL/L 

of Ferrocene as a Function of the Activation Energy of the One-step Ferrocene

Decomposition Reaction.............................................................................................................. 217 

Figure 3–55. Normalized Burning Velocity of CH4/O2/N2 Flames, a) XO2,ox = 0.21, b) XO2,ox 

= 0.244, Inhibited by CO2, by CO2–ferrocene Blends, and by CF3Br ......................................... 219 

Figure 3–56. Normalized Burning Velocity of CH4/N2/O2 Flames, a.) XO2,ox = 0.21, b.)

XO2,ox = 0.244, with 0, 2, and 6, or 0, 6, and 12 Volume Percent of CO2, 

Respectively, Added to the Reactant Stream, as a Function of Added Ferrocene....................... 220 

Figure 3–57. Normalized Burning Velocity of Premixed CH4/O2/N2 Flames Inhibited by Pure

CF3H and by CF3H with 0.35 % Ferrocene, Together with Data for CF3Br................................ 221 
List of Figures xxiii

Figure 3–58. Equilibrium Mole Fraction of Active Inhibiting Species (Fe, FeO, FeOH, 

Fe(OH)2) and Iron-fluorine Species with 1 % to 4 % CF3H (Containing 0.35 % 

Ferrocene) Added to a Stoichiometric Methane-air Reaction Mixture........................................ 222 

Figure 3–59. Linear Contribution of Burning Velocity from Each Component of a twoComponent Blend of Inhibitors, Together with the Actual Reduction from the Blend. .............. 223 

Figure 3–60. Ratio of the Actual Reduction in SL from the Two-component Mix to the 

Predicted Reduction Based on Linear Combination of the Effect from Each 

Component................................................................................................................................... 224 

Figure 3–61. Volume Fraction of Cr-containing Species. Cr, CrO, CrO2, and CrO3 above 

Cr2O3 at 10.133 kPa under Neutral and Oxidizing Conditions above Cr2O3 and Cr 

above itself .................................................................................................................................. 225 

Figure 3–62. Pb Species Gas Phase Volume Fractions at Equilibrium over the Condensed 

Phase (at 101.3 kPa)..................................................................................................................... 226 

Figure 3–63. Normalized Burning Velocity of Premixed CH4/O2/N2 Flames Inhibited by 

MMT with XO2,ox = 0.21 and φ = 0.9, 1.0, and 1.1....................................................................... 227 

Figure 3–64. Mn Species Gas Phase Volume Fraction at Equilibrium over the Condensed 

Phase at 101.3 kPa. ...................................................................................................................... 227 

Figure 3–65. Tungsten-containing Species Gas Phase Volume Fraction at Equilibrium over 

the Condensed Phase at 101.3 kPa............................................................................................... 228 

Figure 3–66. Mo-containing Species Gas Phase Volume Fraction at Equilibrium over the 

Condensed Phase at 101.3 kPa..................................................................................................... 229 

Figure 3–67. Normalized Burning Velocity of Premixed CH4/O2/N2 Flames Inhibited by 

TMT with XO2,ox = 0.21 and φ = 0.9, 1.0, and 1.1........................................................................ 229 

Figure 3–68. Sn-containing Species Gas Phase Volume Fractions at Equilibrium over the 

Condensed Phase at 101.3 kPa..................................................................................................... 230 

Figure 3–69 Co-containing Species Gas Phase Volume Fraction at Equilibrium over the 

Condensed Phase at 101.3 kPa..................................................................................................... 230 

Figure 3–70. Cu-containing Species Gas Phase Volume Fractions at Equilibrium over the 

Condensed Phase at 101.3 kPa..................................................................................................... 231 

Figure 3–71. Equivalent N2/O2 Limiting Oxygen Index for Extinction of Polyethylene (PE)-

halogen- Sb2O3 Blends and Methane-air Cup Burner Flames with MMT, Fe(CO)5, 

and Sn(CH3)4................................................................................................................................ 232 

Figure 3–72. Schematic of Opposed-jet Burner........................................................................................ 239 

Figure 3–73. Schematic of LIF Apparatus................................................................................................ 241 

Figure 3–74. Variation of Global Extinction Strain with Observed Flame Position at 

Extinction..................................................................................................................................... 246 

Figure 3–75. Variation of Global Extinction Strain with Observed Flame Position at 

Extinction for Non-premixed CH4/N2-O2/N2 Flames, with Z st = 0.50. ....................................... 247 

Figure 3–76. Observed Flame Positions as a Function of Predicted Distance to the Stagnation 

Plane for Non-premixed Flames of CH4-air (Zst = 0.054), and CH4/N2-O2/N2 Flames, 

(Z st = 0.50) Near Extinction. ....................................................................................................... 248 
xxiv List of Figures 

Figure 3–77. Inhibition of Non-premixed Methane-air Flames, Based on Reduction in the

Global Extinction Strain Rate by Oxidizer-side Addition of Nitrogen, with and

without Preheated Reactants. ....................................................................................................... 249 

Figure 3–78. Inhibition of Non-premixed Methane-air flames, Based on Reduction in the 

Global Extinction Strain Rate, by Oxidizer-side Addition of Trimethyl Phosphate 

(TMP), and Dimethyl Methylphosphonate (DMMP). ................................................................. 250 

Figure 3–79. Adiabatic Flame Temperature vs. Stoichiometric Mixture Fraction for a 

Methane-nitrogen-oxygen-nitrogen Flame with the Extinction Strain Rate Held 

Constant at 350 ± 10 s-1................................................................................................................ 252 

Figure 3–80. Flame Suppression Effectiveness of 25,000 μL/L Argon as an Oxidant-side or

Fuel-side Additive vs. Stoichiometric Mixture Fraction.............................................................. 253 

Figure 3–81. Normalized Flame Suppression Effectiveness of Argon-doped Flames vs. 

Stoichiometric Mixture Fraction at Fixed.................................................................................... 253

Figure 3–82. Flame Suppression Effectiveness of 500 μL/L DMMP as an Oxidant-side or

Fuel-side Additive vs. Stoichiometric Mixture Fraction.............................................................. 254 

Figure 3–83. Normalized Flame Suppression Effectiveness of DMMP-doped Flames vs. 

Stoichiometric Mixture Fraction.................................................................................................. 255 

Figure 3–84. Normalized effectiveness of DMMP-doped Flames as a Function of Adiabatic 

Flame Temperature. ..................................................................................................................... 256 

Figure 3–85. Calculated Major Species and Temperature Profiles for Flame 1 and Flame 4,

both undoped................................................................................................................................ 258 

Figure 3–86. Calculated and Measured OH Concentration Profiles for Flames 1 and 4.......................... 258 

Figure 3–87. [OH] Profile Widths (FWHM). ........................................................................................... 259 

Figure 3–88. Effect of 572 μL/L of DMMP on [OH] in Flame 1. 260 

Figure 3–89. Effect of DMMP Loading for All Flames. .......................................................................... 261 

Figure 3–90. Temperature Dependence of Effectiveness. ........................................................................ 262 

Figure 3–91. Effect of 572 μL/L of DMMP on Calculated OH, H, and O Concentration

Profiles in Flame 1 (CH4/O2/N2).................................................................................................. 263 

Figure 3–92. Temperature Dependence of Effectiveness Defined as in Terms of Reduction in 

total [OH]..................................................................................................................................... 264 

Figure 3–93. OH, H, and O Production Rates in Flame 1 and Flame 4, Summed over All 

Reactions Involving Phosphorus.................................................................................................. 264 

Figure 3–94. Total OH Production Rates in Flame 1 by Reactions Not Involving Phosphorus............... 265 

Figure 3–95. Influence of the Addition of 572 μL/L of DMMP on OH Production Rates in

Flame 1.. ...................................................................................................................................... 266 

Figure 3–96. H and O Production Rates by All Reactions Involving Phosphorus and by 

Individual Reactions in Flame 1. ................................................................................................. 267 

Figure 3–97. Temperature Profiles Measured in (a) Rich and (b) Near-stoichiometric Flames............... 274 

Figure 3–98. CH4 in Doped and Undoped (a) Rich and (b) Near-stoichiometric Flames, with

GRI and Babushok and Glaude Predictions................................................................................. 275 
List of Figures xxv

Figure 3–99. CO2 in Doped and Undoped (a) Rich and (b) Near-stoichiometric Flames, with 

GRI and Babushok and GlaudePredictions.................................................................................. 275 

Figure 3–100. CO in Doped and Undoped (a) Rich and (b) Near-stoichiometric Flames, with 

GRI and Babushok and Glaude Predictions................................................................................. 276 

Figure 3–101. CH2O in Doped and Undoped (a) Rich and (b) Near-stoichiometric Flames, 

with GRI and Babushok and Glaude Predictions......................................................................... 276 

Figure 3–102. C2H2 in Doped and Undoped (a) Rich and (b) Near-stoichiometric Flames, 

with GRI and Babushok and Glaude Predictions......................................................................... 277 

Figure 3–103. C2H4 in Doped and Undoped (a) Rich and (b) Near-stoichiometric Flames, 

with GRI and Babushok and Glaude Predictions......................................................................... 277 

Figure 3–104. C2H6 in Doped and Undoped (a) Rich and (b) Near-stoichiometric Flames, 

with GRI and Babushok and Glaude Predictions......................................................................... 278 

Figure 3–105. CH3OH in Doped and Undoped (a) Rich and (b) Near-stoichiometric Flames, 

with GRI and Babushok and Glaude Predictions......................................................................... 278 

Figure 3–106. Schematic Diagram of the Experimental Apparatus. ........................................................ 283 

Figure 3–107. Representative PLIF Images and the Corresponding OH Intensity Profiles from 

an Opposed Flow Propane-air Flame Seeded with 0 % (by volume) CF3Br and 1.5 % 

(by volume) CF3Br....................................................................................................................... 284 

Figure 3–108. Normalized OH LIF Profile Areas vs. Inhibitor Agent Delivery 

Concentrations. □: N2, О: HFC-227ea, ∆: HFC-236, : PN, ◊: CF3Br, ■: DMMP, and 

●: Fe(CO)5. Insert: Expanded data for PN, CF3Br, DMMP, and Fe(CO)5

Concentrations up to 0.75 % by Volume. .................................................................................... 286 

Figure 3–109. Peak LIF Measured Temperatures vs. Inhibitor Delivery Concentrations.. ...................... 288 

Figure 3–110. Calculated Burning Velocities vs. Delivered Inhibitor Concentration for a 

Numerical, Stoichiometric, Premixed, Propane-air Flame. ......................................................... 289 

Figure 3–111. Normalized OH Concentrations vs. Delivered Inhibitor Concentrations. ......................... 290 

Figure 3–112. Burning Velocity, Final Flame Temperature, Inhibition Parameter, and 

Superequilibrium Concentrations of Flame Radicals Computed for Atmospheric 

Pressure Stoichiometric Methane-air Mixtures Inhibited by NaOH............................................ 293 

Figure 3–113. Burning Velocity, Final Flame Temperature, Inhibition Parameter, and 

Superequilibrium Concentrations of Flame Radicals Computed for Atmospheric 

Pressure Stoichiometric Methane-air Mixtures Inhibited by CF3Br. ........................................... 293 

Figure 3–114. Burning Velocity and Differential Inhibition Parameter computed for 

Atmospheric Pressure Stoichiometric Methane-air Mixtures Inhibited by N2 and FeO2

in Combination. ........................................................................................................................... 295 

Figure 3–115. Relationship between Burning Velocity and Peak Concentration of Atomic 

Hydrogen for Methane-air Flames Inhibited by Various Compounds......................................... 296 

Figure 3–116. Mole Fraction of Atomic Hydrogen as a Function of Local Flame Temperature 

for an Uninhibited and Uninhibited Atmospheric Pressure Methane-air Flame.......................... 298 

Figure 3–117. Calculated Flame Velocity as a Function of Hypothetical Variation of the H-Br 

Bond Energy for Premixed Methane-air Flames Inhibited by 0.5 % HBr Using the H 

+ H and H + OH Scavenging Cycles of Table 3.......................................................................... 304 
xxvi List of Figures 

Figure 3–118. Calculated Flame Velocity as a Function of Hypothetical Variation of the NaOH Bond Energy for Premixed Methane-air Flames Inhibited by 0.1 % (NaOH)2

using the H + OH scavenging cycle of Table 3 ........................................................................... 305 

Figure 3–119. Calculated Flame Velocity as a Function of Hypothetically Variation of Fe-O 

Bond Energy for Premixed Methane-air Flames Inhibited by 500 μL/L FeO2 Using

the Three-step O + O Scavenging Cycle of Table 3 .................................................................... 306 

Figure 3–120. Shapes of the Reaction Rate Profile Bi Used to Describe: a) Perturbation of

Chain Branching and Heat Release Rates, b) Addition of Perfect Inhibitor or CF3Br ,

c) Rapid Inhibitor Activation, and d) Rapid Inhibitor Deactivation. ........................................... 308 

Figure 3–121. Variation of Flame Speed for Four Types of Perturbation. ............................................... 311 

Figure 3–122. Net H-atom Reaction Rate for Three Important Reactions in Stoichiometric 

Methane-air Flames. .................................................................................................................... 312 

Figure 3–123 Effect of damping the rate of the H+O2 reaction on normalized flame speed for 

φ=0.7, 1.0, and 1.3. ...................................................................................................................... 313 

Figure 3–124. Calculated Volume Fraction Profiles for H, OH and O in Uninhibited 

Methane-air Flames for Three Stoichiometric Ratios.................................................................. 313 

Figure 3–125. Effect of the Location of Perfect Inhibition on Normalized Flame Speed for

φ=0.7, 1.0, and 1.3.. ..................................................................................................................... 314 

Figure 3–126. Variation of Flame Speed for Stepwise Inhibitor Activation or Deactivation for

a Stoichiometric Methane-air Mixture......................................................................................... 315 

Figure 4–1. Water Mist Size Histogram and Values of Several Mean Diameters.................................... 349 

Figure 4–2. Lognormal and Rosin-Rammler Expressions Fit to the Water Mist Histogram 

Presented in Figure 4–1. .............................................................................................................. 350 

Figure 4–3. Schematic Diagram for Diffraction-based Particle Sizing. ................................................... 352 

Figure 4–4. Diagram for 1-D Phase Doppler Interferometry System for Obtaining Size and 

Velocity of “Spherical” Aerosol Particles. .................................................................................. 353

Figure 4–5. Schematic Diagram for Imaging-based Particle Sizing......................................................... 354 

Figure 4–6. Predicted Evaporation Times for Water Droplets in Air at the Indicated

Temperature as a Function of Initial Droplet Diameter............................................................... 357 

Figure 4–7 Predicted Terminal Settling Velocity for Water Droplets and Sodium Bicarbonate 

Particles in Air at 20 oC................................................................................................................ 357 

Figure 4–8. Relationship of Flame Dimensionality and Modeling Complexity. ...................................... 359 

Figure 4–9. Representations of Aerosol Suppressed Premixed Flames.................................................... 359 

Figure 4–10. Experimental Schematic for Studying the Effects of Aerosols on the Extinction

Strain Rate of Counterflow Non-Premixed Flames. .................................................................... 361 

Figure 4–11. Schematic of Tsuji Burner and Flame Configuration.......................................................... 362 

Figure 4–12. Cup Burner Apparatus Modified for Water Mist Suppression Studies. .............................. 363 

Figure 4–13. Schematic of Water Aerosol Generation Methods.. ............................................................ 364 
List of Figures xxvii

Figure 4–14. PDPA-determined Droplet Diameter Histogram 2 mm above the Air Tube Exit 

for Three Water Mists.................................................................................................................. 364 

Figure 4–15. Schematic for Liquid Aerosol Inhibited Burning Velocity Determination in 

Premixed Flames.......................................................................................................................... 365 

Figure 4–16. Predicted Burning Velocity for a Stoichiometric, Premixed, Methane-air Flame 

as a Function of Initial Droplet Diameter and Water Mass Loading ........................................... 367 

Figure 4–17. (a) Image of Premixed Methane-air Flame Stabilized on Burner; (b) Image of 

Water Mist (no flame) as it Exits the Burner; (c) Image of Laser-illuminated Water 

Mist and Methane-air Flame Showing Disappearance of the Mist at the Flame 

Boundary...................................................................................................................................... 367 

Figure 4–18. Normalized Burning Velocity Reduction vs. Mass of Added Inhibitor for an 

Inhibited Methane-Air Premixed Flame. ..................................................................................... 368 

Figure 4–19. Premixed Methane-air Burning Velocity as a Function of Agent Mass Fraction, 

Normalized by the Uninhibited Burning Velocity....................................................................... 369 

Figure 4–20. Measurements of Water Droplet Diameter and Number Density in a 

Stoichiometric Premixed Methane-air Flame as a Function of Height above the 

Burner Exit................................................................................................................................... 370 

Figure 4–21. Multi-phase Predictions of Water Mist Droplet Diameter and Number Density 

in a Stoichiometric Premixed Methane-air Flame. ...................................................................... 370 

Figure 4–22. Predicted Comparison of the Maximum Flame Temperature, Tmax, vs. Flow 

Strain Rate, a, for a Dry Flame and for Four Flames with Different Inflow Water 

Vapor Partial Pressures................................................................................................................ 373 

Figure 4–23. Calculated Gas Velocity, Velocities for Varied Water Droplet Diameters, and 

Gas Temperature (thick solid line) in a 130 s-1 Methane/air Flame with Droplet 

Source Terms turned “off”........................................................................................................... 375 

Figure 4–24. Comparison of U of Gas and Ud of Different Droplet Diameters, with Droplet 

Source Terms Turned “off”. ........................................................................................................ 376 

Figure 4–25. Comparison of Droplet Temperature, Td, of Different Droplet Diameters, with 

Droplet Source Terms Turned “off”. ........................................................................................... 377 

Figure 4–26. Comparison of Flux Fraction Function, F, of Different Droplet Diameters, with 

Droplet Source Terms Turned “off”. ........................................................................................... 377 

Figure 4–27. Typical Sm Profiles of Different Droplet Diameters, with Y0 = 0.02 and Droplet 

Source Terms Turned “off” ......................................................................................................... 378 

Figure 4–28. Typical SU - USm Profiles of Different Droplet Diameters, with Y0 = 0.02 and 

Droplet Source Terms Turned “off” ........................................................................................... 379 

Figure 4–29. Typical Sh - hiSm Profiles of Different Droplet Diameters, with Y0 = 0.02 and 

Droplet Source Terms Turned “off” ............................................................................................ 379 

Figure 4–30. Comparison of Tmax vs. Strain Rate for Different Droplet Diameters, with Water 

Mass Fraction = 0.01 ................................................................................................................... 379 

Figure 4–31. Comparison of Tmax vs. Strain Rate for Different Droplet Diameters, with Water 

Mass Fraction = 0.02. .................................................................................................................. 380 
xxviii List of Figures 

Figure 4–32. Comparison of Tmax vs. strain rate for Different Droplet Diameters, with Water

Mass Fraction = 0.03. .................................................................................................................. 380 

Figure 4–33. Comparison of aext vs. Droplet Diameter for Different Droplet Mass Fractions in

the Condensed Phase at Inflow. ................................................................................................... 381 

Figure 4–34. Comparison of (χs)ext vs. Droplet Diameter for Different Droplet Mass

Fractions in Condensed Phase at Inflow...................................................................................... 382

Figure 4–35. Calculated Droplet Trajectory as a Function of Time, for d = 50 μm and Y0 = 

0.03. ............................................................................................................................................. 383 

Figure 4–36. Apparatus for Aerosol-inhibited, Non-premixed Counterflow Flames. .............................. 384 

Figure 4–37. Droplet Diameter Distribution Evolution of a 30 μm Mist in a 170 s–1 Strain

Rate Flame ................................................................................................................................... 387 

Figure 4–38 Droplet Diameter Distribution Evolution of an 18 μm Mist in a 170 s-1 Strain

Rate Propane/air Counterflow Flame........................................................................................... 388 

Figure 4–39. Profiles of Number Density and Velocity of 30μm Droplets vs. Location in a 

170 s-1 Strain Rate Propane/air/30μm Mist Counterflow Flame.................................................. 389 

Figure 4–40. Profiles of Number Density) and Velocity of 18 μm Droplets vs. Location in a 

Propane/air/water mist Counterflow Flame. ................................................................................ 389 

Figure 4–41. Droplet Flux Profile for a 30μm Mist in a 170 s-1 Strain Rate Propane/air Flame. ............. 390 

Figure 4–42. Water Mist Effects on the Extinction of Non-premixed, Counterflow

Propane/air Flames: (a) Flame Extinction Strain Rate as a Function of Mass of Water

or Halon 1301 in the Air Flow; (b) Mass Fraction of Water Needed to Extinguish the 

Flames as a Function of Droplet Diameter, Compared to Mass of Gas-phase Halon 

1301. ............................................................................................................................................ 391 

Figure 4–43. Variation of the Predicted Flame Temperature as a Function of the Flow Strain 

Rate for Propane-air, Non-premixed Counterflow Flames for Dry Air, Air Saturated 

with Water Vapor, and Saturated Air with Monodisperse Water Droplets. ................................ 393 

Figure 4–44. Measured Extinction Strain Rate for Water Mist Suppressed Propane-air, Nonpremixed Counterflow Flames vs. % Mass of Condensed-phase Water in the Air and 

Calculated Results for 14 μm, 30 μm, and 42 μm Diameter Monodisperse Water 

Mists in Saturated Air at 300 K. .................................................................................................. 394 

Figure 4–45 Calculated Humidification Levels of a 296 K Air Stream Containing 14 μm, 30

μm, or 42 μm droplets, Following a Residence Time of 750 ms Starting in Dry Air,

as a Function of the Mass Fraction of Liquid Water Remaining after Droplet 

Evaporation.................................................................................................................................. 395 

Figure 4–46. Schematic of the Non-premixed Counterflow Burner and Calculated 

Temperature, O, H, and OH Profiles for the Low Strain Flame. ................................................. 398 

Figure 4–47. Powder Delivery System. .................................................................................................... 399 

Figure 4–48. Typical Micrographs of NaHCO3 Powder Samples. ........................................................... 400 

Figure 4–49. Typical Micrographs of KHCO3 Powder. ........................................................................... 400 

Figure 4–50. Extinction Mass Concentration as a Function of Strain Rate for Various Particle

Sizes Ranges of NaHCO3 and KHCO3 Powders in a Propane/air, Counterflow, Nonpremixed Flame. .......................................................................................................................... 401 
List of Figures xxix

Figure 4–51. Data from Figure 4–50 Plotted to Show Extinction Mass Concentration as a 

Function of Particle Size Range for Each Flame Strain Rate and Added Powder....................... 402 

Figure 4–52. Extinction Mass Concentration as a Function of (a) Average Particle Diameter 

and Average Particle Surface Area for NaHCO3 and KHCO3 Powders in a Medium 

Strain Rate (310 s-1) Propane/air Counterflow Non-premixed Flame.......................................... 403 

Figure 4–53. Calculated Particle Asymptotic Location as a Function of Particle Diameter for 

the Flow Conditions of the Low Strain Propane/air Flame.......................................................... 405 

Figure 4–54. Schematic of the Counterflow Flame Apparatus with the Particle Seeder.......................... 407 

Figure 4–55. % NaHCO3 by Mass in air as a Function of Extinction Strain Rate for Different 

Size Groups of Particles............................................................................................................... 409 

Figure 4–56. Numerical Prediction of NaHCO3 Mass Fraction as a Function of Extinction 

Strain Rate, for Selected Particle Sizes........................................................................................ 411 

Figure 4–57. Schematic of the Counterflow Burner Configuration with the Water Droplet 

Atomizer. ..................................................................................................................................... 413 

Figure 4–58. (a) Normalized Droplet Diameter Distribution of the Ultrasonic Atomizer as 

Reported by the Manufacturer; (b) and (c) Normalized Water Droplet Diameter 

Distributions Measured Using a PDPA at the Exit of the Air Nozzle for an Air Flow 

Corresponding to Counterflow Strain Rates of 285 s-1 and 160 s-1, Respectively. ...................... 415 

Figure 4–59. Variation of Water Droplet Mass Fraction in the Condensed Phase as a Function 

of Flame Extinction Strain Rate................................................................................................... 417 

Figure 4–60. Droplet Mass Fraction in the Condensed Phase as a Function of Flame 

Extinction Strain Rate for Different Mass Loadings of NaOH in Water..................................... 418 

Figure 4–61. Variation of the Maximum Flame Temperature as a Function of Local Flow 

Strain Rate for Constant Droplet Mass Fractions and Constant Water Mass Flux 

Rates............................................................................................................................................. 419 

Figure 4–62. Droplet Mass Fraction as a Function of Extinction Strain Rate of a Methane/air 

Non-premixed Flame for Several NaOH Mass Fractions in Water. ............................................ 422 

Figure 4–63. Y0 and Mole Fraction of NaOH in Air as a Function of yNaOH for the Extinction 

Strain of 125 s-1 in Figure 4–62. .................................................................................................. 423 

Figure 4–64. Droplet Mass Fraction as a Function of Extinction Strain Rate of a Methane/air 

Non-premixed Flame for Several KOH Mass Fractions in Water............................................... 424 

Figure 4–65. Droplet Mass Fraction as a Function of Extinction Strain Rate of a Methane/air 

Non-premixed Flame for NaCl and FeCl2 in Water..................................................................... 425 

Figure 4–66. Upper panel: Mole Fraction of Alkali Metal Atoms in Air as a Function of Nonpremixed Methane/air Flame Extinction Strain Rate for NaOH and KOH Mass 

Fractions of 0.055 shown in Figure 4. Lower panel: Mole Faction of Am in Air as a 

Function of Non-premixed Methane/air Flame Extinction Strain Rate for NaOH and 

NaCl Mass Fractions of 0.03 Shown in Figure 4–63 and Figure 4–66 (upper panel). ................ 425 

Figure 4–67. Square of the Normalized Burning Velocity of a Premixed Flame Inhibited with 

Fine Droplets of Water Solution for Several NaOH Mass Fractions in Water............................ 427 

Figure 4–68. Normalized Flame Strength of Non-premixed and Premixed Methane/air Flames 

Inhibited with Droplets of Water with a Median Diameter of 20 μm.......................................... 428 
xxx List of Figures 

Figure 4–69. Non-premixed and Premixed Flame Structures Corresponding to Inhibited 

Conditions of Water Droplet Mass Fraction of Y0 = 0.01. .......................................................... 429 

Figure 4–70. Setup for JP-8 Fire Suppression Experiments. .................................................................... 432 

Figure 4–71. Blow-off Velocity Ratios for Various Candidate Agents to Air, and Reference 

Ratios for Water to Air Measured under the Same Conditions. .................................................. 434 

Figure 4–72. Blow-off Velocity Ratios for Various Candidate Agents to Air, and Reference 

Ratios for Water to Air Measured under the Same Conditions ................................................... 434 

Figure 4–73. Times for Various Experimental Fire Suppressants to Extinguish a 200 mL JP-8

Pan Fire........................................................................................................................................ 436 

Figure 4–74. Mass of Various Experimental Fire Suppressants to Extinguish a 200 mL JP-8

Pan Fire........................................................................................................................................ 437 

Figure 4–75. Mass flows for Various Fire Suppressants Deployed during JP-8 Screening

Experiments. ................................................................................................................................ 437 

Figure 4–76. Droplet Evaporation Time as a Function of Initial Droplet Diameter for Five 

Fluids. .......................................................................................................................................... 442 

Figure 4–77. Typical Boiling Curve Associated with Quenching of a Hot Surface by Liquid

Droplets........................................................................................................................................ 443 

Figure 4–78. Calculated Boiling Curves in the Convective Regime for Five Liquids. ............................ 445 

Figure 4–79. Calculated Boiling Curves for Five Liquids for the Transition and Film Boiling

Regimes. ...................................................................................................................................... 447 

Figure 4–80. Wind Tunnel Used for Fire Spread Studies......................................................................... 449 

Figure 4–81. Flame Spread Experiment with Water Mist. ....................................................................... 450

Figure 4–82. Schematic of the Two-color Planar Pyrometer.................................................................... 451

Figure 4–83. Typical Flame Spread Time Trace Obtained using Focal Plane Array Imaging................. 452 

Figure 4–84. Flame Spread Rates without Water Mist............................................................................. 452 

Figure 4–85. Flame Spread Rate as a Function of Surface Loading for 3.2 mm Thick PMMA. ............. 454 

Figure 4–86. Flame Spread Rate as a Function of Surface Loading for 0.64 cm Thick PMMA.............. 455 

Figure 4–87. Mean Droplet Size and Velocity as a Function of Spray Nozzle Discharge Rate............... 456 

Figure 4–88. Variation in Normalized Flame Spread with Liquid Loading. ............................................ 457 

Figure 4–89. Mean Flame Temperature Obtained Using the TCPP. ........................................................ 457 

Figure 4–90. Experimental Arrangement for the Measurements.............................................................. 458 

Figure 4–91. Configuration of the Piezoelectric Atomizer....................................................................... 459 

Figure 4–92. Schematic Diagram of the Heater Assembly....................................................................... 460

Figure 4–93. Temperature Measurement Locations on the Heater........................................................... 460 

Figure 4–94. Steady State Temperature Field above the Hot Plate. ......................................................... 463 

Figure 4–95. Change in Sauter Mean Diameter of the Water Droplets with Axial Distance. .................. 464 

Figure 4–96. Change in Sauter Mean Diameter of the Droplets with Axial Distance for 

Fluid 510...................................................................................................................................... 464 
List of Figures xxxi

Figure 4–97. Variation in Velocity with Axial Distance for Water Spray................................................ 465 

Figure 4–98. Variation in Velocity with Axial Distance for Fluid 510. ................................................... 465 

Figure 5–1. Schematic of Laser Induced Breakdown Spectroscopy (LIBS) Measurement 

Apparatus. .................................................................................................................................... 484 

Figure 5–2. Measured Concentrations of Fluorinated Fire Suppressants using LIBS. ............................. 484 

Figure 5–3. Successive Signal Improvements in the Detection of HF using TDLAS. ............................. 487 

Figure 5–4. Schematic of TDLAS Apparatus for Measurement of Gases Produced during Fire 

Suppression in Ground Vehicles.................................................................................................. 487 

Figure 5–5. HF Gas Produced during Suppression of Heptane Pan Fires by HFC-236 with and 

without the Addition of Ammonium Polyphosphate).................................................................. 489 

Figure 5–6. Oxygen Concentration Measured Within the Crew Compartment of a Bradley 

Fighting Vehicle During Suppression by C3F8 of a Spark-Initiated JP-8 Spray Fire................... 491 

Figure 5–7. FT-IR Spectra of Dry Air Saturated at 294 K with Vapor from Unleaded 

gasoline, JP-8, and DF-2.............................................................................................................. 492 

Figure 5–8. Schematic Diagram of the Laser Mixing Apparatus Used to Measure Fuel Vapor 

Concentrations. ............................................................................................................................ 495 

Figure 5–9. Absorption Spectrum of Air Saturated with JP-8, DF-2, or Gasoline Vapor at 294 

K Superimposed upon the Emission from the Optical Fiber Carrying the Mixed 

Wavelength Laser Beam. ............................................................................................................. 496 

Figure 5–10. Concentrations of Gasoline Vapor and Oxygen, Measured as Dry Air Saturated 

with JP-8 Vapor Displaces the Dry Air in a 13.7 L Optical Cell................................................. 497 

Figure 5–11. Loss of Lighter Hydrocarbons from JP-8 Caused by Repeated Fills of the 

Optical Cell Used for Testing the Mixed Laser Fuel Vapor Sensor. ........................................... 497 

Figure 5–12. Two Laser Interferogram Measured at the Detector for the Second Generation 

Fuel Vapor Sensor. ...................................................................................................................... 498 

Figure 5–13. Experimental Apparatus Used for Fourier Transform Laser Spectroscopy. ....................... 500 

Figure 5–14. Absorption of 1.71 μm Laser Radiation as Air is Displaced by Air Saturated 

with Gasoline Vapor in a 2 m Cell............................................................................................... 500 

Figure 5–15. Schematic of a 10-laser FT-LS Source in the Near Infrared. .............................................. 501 

Figure 5–16. Schematic of the DIRRACS I.............................................................................................. 503 

Figure 5–17. Schematic of the Optical Design Used in DIRRACS I. ...................................................... 503 

Figure 5–18. Absorption Spectrum of HFC-125 Superimposed with the Transmittance 

Spectrum for the Bandpass Filter................................................................................................. 504 

Figure 5–19. Schematic of DIRRACS II. ................................................................................................. 506 

Figure 5–20. Photograph of the DIRRACS II with the Periscope Mounted within the Flow 

Channel of the TARPF Facility. .................................................................................................. 506 

Figure 5–21. Calibration Plot of Average Normalized Peak-to-valley Signals vs. Volume 

Fraction of HFC-125.................................................................................................................... 508 
xxxii List of Figures 

Figure 5–22. Normalized Peak-to-valley Signals Resulting from Processing the Raw Signal 

from the DIRRACS II for Two Releases of HFC125.................................................................. 510 

Figure 5–23. HFC-125 Volume Fraction vs. Time for Two Releases of HFC-125 in the

TARPF Facility............................................................................................................................ 510 

Figure 5–24. Bradley Armored Personnel Carrier Modified for Performing Agent Release and 

Fire Suppression Studies.............................................................................................................. 511 

Figure 5–25. Interior of the Bradley Vehicle Showing the Periscope of the DIRRACS II in 

the “High” Location..................................................................................................................... 511 

Figure 5–26. HFC-125 Volume Fraction and Cylinder Pressure vs. Time at the Upper

Measurement Position.................................................................................................................. 512 

Figure 5–27. HFC-125 Volume Fractions vs. Time at the High and Low Positions During

Two Different Releases................................................................................................................ 512 

Figure 6–1. Schematic of the Cup Burner Apparatus. .............................................................................. 523 

Figure 6–2. Photographs of a Standard Cup Burner. ................................................................................ 523 

Figure 6–3. Schematic of Sample Nebulizer. ........................................................................................... 524 

Figure 6–4. Heated Cup Burner for Appraising High-boiling Flame Suppressants. ................................ 525 

Figure 6–5. Schematic of the DLAFSS Wind Tunnel. ............................................................................. 526 

Figure 6–6. Photograph of the DLAFSS Wind Tunnel............................................................................. 527 

Figure 6–7. Cut-away View of the DLAFSS Burner Insert...................................................................... 528 

Figure 6–8. Photograph of the DLAFSS Burner Assembly...................................................................... 528 

Figure 6–9. An Enveloped Flame and a Wake Flame .............................................................................. 529 

Figure 6–10. Schematic of the DLAFSS Nebulizer.................................................................................. 531 

Figure 6–11. Screening Results for Various Aqueous Fluids................................................................... 533

Figure 6–12. Schematic of Step-stabilized Pool Fire Apparatus. ............................................................. 537 

Figure 6–13. Photograph of the TARPF. .................................................................................................. 538 

Figure 6–14. Photograph of a Baffle-stabilized Propane Flame in the TARPF........................................ 538 

Figure 6–15. Liquid Aerosol Agent Injection System. ............................................................................. 540 

Figure 6–16. Schematic Diagram of the SPGG Injection System. ........................................................... 541 

Figure 6–17. Photograph of TARPF Injection System with Housing Cover Removed. ......................... 541 

Figure 6–18. Disruption of a Stabilized Flame by the Injection of Nitrogen Upstream of 25

mm High Obstacle. ...................................................................................................................... 543 

Figure 6–19. Impact of Air Speed on Extinction of a 25 mm Baffle-stabilized Flame. ........................... 545 

Figure 6–20. Mass and Rate of Nitrogen Addition to Extinguish a 45 mL/s Propane Flame in

3.9 m/s Air Flow .......................................................................................................................... 545 

Figure 6–21. Mass and Rate of Nitrogen Addition Required to Extinguish High Flow and

Low Flow Propane/Air Flames Stabilized Behind a 25 mm Step. .............................................. 546 
List of Figures xxxiii

Figure 6–22. Mass and Rate of Nitrogen Addition Required to Extinguish High Flow and 

Low Flow Propane/Air Flames Stabilized Behind a 10 mm Baffle............................................. 547 

Figure 6–23. Mass and Rate of Nitrogen Addition Required to Extinguish High Flow and 

Low Flow Propane/Air Flames Stabilized Behind a 55 mm Baffle............................................. 547 

Figure 6–24. Impact of Obstacle Height on the Total Mass and Rate of Addition of Nitrogen 

Required to Suppress an Obstacle-stabilized Pool Fire. .............................................................. 548 

Figure 6–25. Mole Faction of Suppressants (N2 and CF3Br) Added to Air at Extinction 

Boundary for High and Low Flow Conditions, as a Function of Injection Time 

Interval and Obstacle Geometry. ................................................................................................. 549 

Figure 6–26. Injection interval and Calculated Mass Delivered to Flame as a Function of Area 

Ratio Times Total Mass of Gas Generated ................................................................................. 551 

Figure 6–27. Percentage of Flames Extinguished as a Function of Mass Delivered to Flame 

by an SPGG ................................................................................................................................ 552 

Figure 6–28. Impact of Injection Time Interval on the Mass of Agent Required to Suppress a 

Step-stabilized Propane Pool Fire................................................................................................ 553 

Figure 6–29. Percentage of Flames Extinguished as a Function of Estimated Mass Fraction of 

Agent............................................................................................................................................ 553 

Figure 6–30. Normalized Volume Fraction as a Function of Non-dimensional Injection 

Interval, Comparing N2, CF3Br, and SPGG................................................................................. 555 

Figure 6–31. Suppression Volume Fraction of Agent (N2 or CF3Br) Normalized by Cup 

Burner Values as a Function of Injection Time Interval Normalized by Characteristic 

Residence Time............................................................................................................................ 556 

Figure 6–32. Schematic of Flash Photolysis Resonance Fluorescence Apparatus for 

Measuring Reactivity of Compound with OH Radicals. ............................................................. 563 

Figure 6–33. Apparatus for Measuring the Absorption Cross Section of Candidate Fire 

Suppressants................................................................................................................................. 567 

Figure 6–34. Estimated Maximum Boiling Points That Can Achieve Selected Values of 

Volume % in Air as a Function of Ambient Temperature........................................................... 573 

Figure 6–35. Comparison of Two Difluorobromopropene Log(KOW) Calculation Methods.................... 587 

Figure 6–36. Comparison of Two Trifluorobromopropene Log(KOW) Calculation Methods................... 588 

Figure 6–37. Hypothetical Time Dependence of a Toxic Response to Exposure to a Fire 

Suppressant .................................................................................................................................. 590 

Figure 6–38. Monte Carlo Simulations of Humans Exposed to Halon 1301............................................ 593 

Figure 6–39. Monte Carlo Simulations of Humans Exposed to HFC-125. .............................................. 593 

Figure 7–1. Groups and Elements Studied................................................................................................ 626 

Figure 7–2. Resorcinol.............................................................................................................................. 635 

Figure 7–3. Vinyl Phosphonates. .............................................................................................................. 636 

Figure 7–4. Example of a Fluoro-substituted Bis(dimethylamino) Cyclotriphosphonitrile. .................... 637 

Figure 7–5. Tris(hydroxymethyl)propane Bicyclic Phosphite.................................................................. 644 
xxxiv List of Figures 

Figure 7–6. Relative Contributions of Liquid Heating, Vaporization, and Gas Heating to 1400 

K to the Total Heat Absorbed by Various Thermal Agents......................................................... 652 

Figure 7–7. Air Velocities at Extinguishment of the DLAFFS Flame as a Function of Liquid 

Application Rate for Lactic Acid/water Mixtures........................................................................ 653 

Figure 7–8. Air Velocities at Extinguishment of the DLAFFS Flame as a Function of Liquid 

Application Rate for HFE-7100................................................................................................... 654 

Figure 7–9. Maximum Flame Temperatures as a Function of the Equal Fuel and Air Velocity 

Magnitudes for a Methane/Air Opposed-Flow Diffusion Flame for Three Versions of

the GRI-Mech Mechanism........................................................................................................... 656 

Figure 7–10. Groups Required for Significant Tropospheric Photodissociation...................................... 662 

Figure 7–11. Formation of a Six-membered Ring Transition State.......................................................... 670 

Figure 7–12. Structural and Optical Isomerism of Bromopentafluoropropene Oxide.............................. 694 

Figure 7–13. Vertical Profiles of CF3I Emissions for Fuel Tank Inerting in Military Aircraft ................ 699 

Figure 8–1. Schematic of Storage and Distribution System for Fire Suppression.................................... 723 

Figure 8–2. Staggered Mesh Numerical Method. ..................................................................................... 737 

Figure 8–3. Curve Fit for Henry’s Constant. ............................................................................................ 746 

Figure 8–4. Effect of Release Coefficient on Calculated Pressure Response........................................... 746 

Figure 8–5. Comparison of Calculated and Measured Bottle Pressure for Test. ...................................... 748 

Figure 8–6. Void Fraction Responses in Lower Portion of Bottle............................................................ 749 

Figure 8–7. 90° Tee Model with Crossflow Junction. .............................................................................. 751 

Figure 8–8. Tee Model with Normal Junctions. ....................................................................................... 752 

Figure 8–9. Schematic of Test Facility: Source Vessel, Discharge Piping, and Collection 

Vessel........................................................................................................................................... 754 

Figure 8–10. Schematic of Source Vessel Showing Mass Inventory Measurement................................. 755 

Figure 8–11. Pressure vs. Temperature Saturation Curve for HFC-227ea and 

HFC-125. ..................................................................................................................................... 756 

Figure 8–12. Schematic of a Marotta valve. ............................................................................................. 757 

Figure 8–13. Top View of Test Facility; Schematic of Discharge Piping System. .................................. 757 

Figure 8–14. Schematic of Pressure Fittings for Temperature and Pressure Ports. .................................. 758 

Figure 8–15. Schematic of Rack Used to Hold the Source Vessel. .......................................................... 759 

Figure 8–16. Picture of Test Facility: Source Vessel, Discharge Piping, Collection Vessel,

Support Structure and Instrumentation ........................................................................................ 760 

Figure 8–17. Pressure Traces for Experimental Run #5. .......................................................................... 761 

Figure 8–18. Repeatability of the Source Vessel Pressure Traces............................................................ 762 

Figure 8–19. Schematic of Alternate Piping Configuration #1................................................................. 763

Figure 8–20. Schematic of Alternate Piping Configuration #2................................................................. 763
List of Figures xxxv

Figure 8–21. Transient Pressure Drop across a 90o Elbow from Run #9.................................................. 764 

Figure 8–22. Diagram of Transducer Setup for Mass Inventory Measurement........................................ 765 

Figure 8–23. Transient Mass Inventory of Run #5. .................................................................................. 766 

Figure 8–24. Schematic of Thermocouple Construction. ......................................................................... 767 

Figure 8–25. Transient Temperature Trace from Film Thermocouples of Run #5................................... 768 

Figure 8–26. Transient Temperature Trace from Shielded Thermocouples of Run #5. ........................... 769 

Figure 8–27. Schematic of Capacitance Probe for Bench Setup. ............................................................. 770 

Figure 8–28. Bench Setup to Test Capacitance Sensor............................................................................. 771 

Figure 8–29. Void Fraction from Bench Tests of Capacitance Sensor..................................................... 771 

Figure 8–30. Schematic of Capacitance Probe for Test Facility............................................................... 772

Figure 8–31. Cross-section of Capacitance Setup Showing Electrical Field............................................ 772 

Figure 8–32. Transient Void Fraction of Run #5...................................................................................... 773 

Figure 8–33. Cumulative Mass as a Function of Time for Runs #1 and #8.............................................. 779 

Figure 8–34. Pressure Drops across Top and Bottom Branch Tees from Run #13. ................................. 781 

Figure 8–35. Comparison of Temperature Traces in the Collection Vessel from Runs #5 and 

#16. .............................................................................................................................................. 782 

Figure 8–36. Void Fraction Measurements from Run #5. ........................................................................ 782

Figure 8–37. Void Fraction Measurements from Run #16. ...................................................................... 783 

Figure 8–38. Pressure Traces from Run #5............................................................................................... 784 

Figure 8–39. Pressure Traces from Run #16............................................................................................. 784 

Figure 8–40. Mass Inventory in the Source Vessel from Run #18. .......................................................... 785 

Figure 8–41. Temperature Traces at Various Positions from Run #18..................................................... 785 

Figure 8–42. Void Fraction Measurements from Run #19. ...................................................................... 786 

Figure 8–43. NIST Test Apparatus........................................................................................................... 787 

Figure 8–44. Piping Configurations for NIST Experiments. .................................................................... 788

Figure 8–45. FSP Input Model.................................................................................................................. 789 

Figure 8–46. Comparison of Calculated and Measured Bottle Pressure for B-59.................................... 790 

Figure 8–47. Comparison of Calculated and Measured Bottle Pressure for B-68.................................... 790 

Figure 8–48. Comparison of Calculated and Measured Bottle Pressure for B-61.................................... 791 

Figure 8–49. Comparison of Calculated and Measured Bottle Pressure for B-60.................................... 791 

Figure 8–50. Comparison of Experimental and Predictive Source Vessel Pressure Data in 

Sensitivity Study on Critical Radius Value for Conditions of Run #4. ....................................... 793 

Figure 8–51. Comparison of Experimental and Predictive Source Vessel Pressure Data in 

Sensitivity Study on Gas Release Rate Value for Conditions of 

Run #4.......................................................................................................................................... 793 
xxxvi List of Figures 

Figure 8–52. Comparison of Experimental and Predictive Void Fraction Data in Sensitivity 

Study on Gas Release Rate Value for Conditions of Run #4....................................................... 794 

Figure 8–53. Comparison of Experimental (in black) and Predictive Pressure Data Using 

Final Values for Code Operating Parameters for Conditions of Run #4. .................................... 795 

Figure 8–54. Comparison of Experimental (in black) and Predictive Void Fraction Data

Using Final Values for Code Operating Parameters for Conditions of Run #4........................... 793 

Figure 8–55. Comparison of Cumulative Mass for Experimental Run #5 and Predictive

Computer Code Data.................................................................................................................... 796 

Figure 8–56. Comparison of Void Fraction for Experimental Run #5 and Predictive Computer 

Code Data .................................................................................................................................... 797 

Figure 8–57. Comparison of Source Vessel Pressure for Experimental Run #5 and Predictive

Computer Code Data.................................................................................................................... 798 

Figure 8–58. Comparison of Pipe Position #1 Pressure for Experimental Run #5 and 

Predictive Computer Code Data .................................................................................................. 798 

Figure 8–59. Comparison of Pipe Position #2 Pressure for Experimental Run #5 and 

Predictive Computer Code Data .................................................................................................. 799 

Figure 8–60. Comparison of Pipe Position #3 Pressure for Experimental Run #5 and 

Predictive Computer Code Data .................................................................................................. 799 

Figure 8–61. Comparison of Collection Vessel Pressure for Experimental Run #5 and 

Predictive Computer Code Data .................................................................................................. 800 

Figure 8–62. Comparison of Pressure Drop across a Capped Tee for Experimental Run #9 

and Predictive Computer Code Data............................................................................................ 801 

Figure 8–63. Comparison of Pressure Drop across a 90o Elbow for Experimental Run #9 and 

Predictive Computer Code Data .................................................................................................. 801 

Figure 8–64. Comparison of Pressure Drop across a Union for Experimental Run #9 and 

Predictive Computer Code Data .................................................................................................. 802 

Figure 8–65. Comparison of Source Vessel Fluid Temperature for Experimental Run #16 and 

Predictive Computer Code Data. ................................................................................................. 803 

Figure 8–66. Comparison of Pipe Position #1 Fluid Temperature for Experimental Run #16 

and Predictive Computer Code Data............................................................................................ 803 

Figure 8–67. Comparison of Collection Vessel Gas Temperature for Experimental Run #16 

and Predictive Computer Code Data............................................................................................ 804 

Figure 8–68. Zone A of the Test Section. ................................................................................................. 806 

Figure 8–69. Clutter Recovery vs. Airspeed............................................................................................. 808 

Figure 8–70. Plenum Recovery vs. Airspeed............................................................................................ 808 

Figure 8–71. Heated Cylinder Test Section. ............................................................................................. 809 

Figure 8–72. Heated Cylinder. (A) Schematic and (B) Front View. ........................................................ 810 

Figure 8–73. Body-centered Cube of Spheres. ......................................................................................... 811 

Figure 8–74. Photographs of Seed/droplet-laden Flow Fields around Obstacles. .................................... 812 
List of Figures xxxvii

Figure 8–75. Variation of the Mean Streamwise and Cross-stream Velocities with 

Downstream Distance for the Unheated Cylinder. ...................................................................... 813 

Figure 8–76. Variation of the Mean Streamwise and Cross-stream Velocities with 

Downstream Distance for the Body-centered Cube of Spheres................................................... 814 

Figure 8–77. View and Schematic of the Experimental Arrangement with the Laser from the 

Phase Doppler Interferometry System. ........................................................................................ 816

Figure 8–78. Schematic of the Measurement Grid around the Cylinder. ................................................. 816 

Figure 8–79. Variation of Water Droplet (A) Sauter Mean Diameter and (B) Mean 

Streamwise Velocity with Streamwise Position at Different Cross-stream Positions 

for the Unheated Cylinder............................................................................................................ 818 

Figure 8–80. Variation of the Streamwise Velocity with Time upstream of the Unheated 

Cylinder at Z = –15 mm and along the Centerline....................................................................... 818 

Figure 8–81. Variation of the Streamwise Velocity with Time at Two Streamwise Positions 

of (A) Z = 25 mm and (B) Z = 76 mm along the Centerline, downstream of the 

Unheated Cylinder within the Recirculation Region. .................................................................. 819 

Figure 8–82. Variation of Water Droplet (A) Sauter Mean Diameter and (B) Mean 

Streamwise Velocity for the Unheated (22 oC)and Heated (150 oC) Cylinders........................... 820 

Figure 8–83. Comparison of the Droplet Mean Size and Streamwise Velocity for the Three 

Agents. ......................................................................................................................................... 820 

Figure 8–84. USNA Wind Tunnel Schematic. ......................................................................................... 822 

Figure 8–85. Low-speed, High-turbulence, Open Jet USNA Wind Tunnel. ............................................ 822 

Figure 8–86. Photograph of the Wire Bundle Model................................................................................ 824 

Figure 8–87. Photograph of the Tandem Medium Cylinder Model.......................................................... 824 

Figure 8–88. Photograph of the Cube Model............................................................................................ 825 

Figure 8–89. Strouhal Number vs. Reynolds Number for the Various Tested Configurations. ............... 828 

Figure 8–90. Schematic of the Test Fixture (ELEFANT)......................................................................... 830 

Figure 8–91. Absorption Spectrum of CF3I. ............................................................................................. 833 

Figure 8–92. Calibration Curve at 300 nm. .............................................................................................. 834 

Figure 8–93. Variation of Bottle Pressure during Discharge at Room and Cold Temperatures............... 834 

Figure 8–94. CF3I Concentration Profiles at the Forward Port................................................................. 836 

Figure 8–95. CF3I Concentration Profiles at the Aft Port......................................................................... 836 

Figure 8–96. Calculated Liquid Fraction as a Function of Bottle Temperature. ...................................... 838 

Figure 8–97. Photograph of the Quarter-Scale Nacelle Test Facility with LDV apparatus...................... 848 

Figure 8–98. Measurement Stations in the Quarter-Scale Nacelle. .......................................................... 848 

Figure 8–99. VULCAN Gridding for the Quarter-Scale Nacelle. ............................................................ 850 

Figure 8–100. Section of the CFD-ACE Grid Used in the Simulation..................................................... 851 

Figure 8–101. Inlet Velocity Profile. ........................................................................................................ 851 

Figure 8–102. Inlet Turbulence Intensity Profile...................................................................................... 852 
xxxviii List of Figures 

Figure 8–103. Velocity and Turbulence Intensity Profiles at Measurement Station 4. ............................ 852 

Figure 8–104. Velocity and Turbulence Intensity Profiles at Mid-nacelle. .............................................. 853 

Figure 8–105. Comparison of Simulation and Experimental Data at the Exit Cone. ............................... 853 

Figure 8–106. Velocity and Turbulence Intensity Profiles Flow in the Exit Pipe. ................................... 854 

Figure 8–107. Ray Tracing Image of Case A1 before Agent Injection and 0.2 s after Injection 

of 10% HFC-125 Images of Case A3 and A5 before Agent Injection......................................... 856 

Figure 8–108. Centerline Contour Plots Showing (from top to bottom) the Temperature, 

Oxygen Mass Fraction, Fuel Mass Fraction and the Computational Grid for Case A1. ............. 857 

Figure 8–109. (a) Evolution of the Maximum Fluid Cell Temperature in the Domain for Case

A1 for Various HFC-125 Mole Fractions. (b) Suppression Times as a Function of 

Added HFC-125 for Cases A1, A3 and A5. (c) Mass Fraction and Temperature 

Evolution in the Recirculation Zone (8 mm above pool and 8 mm behind step) for

Case A1 with 10 % HFC-125 by Volume Injected at 5 s. ........................................................... 858 

Figure 8–110. Centerline Contour Plots of Temperature and HFC-125 Mass Fraction at 0.1 s 

and 0.2 s after Suppressant Injection for Case A1 with 0.1 HFC-125 Mole Fraction 

Injected......................................................................................................................................... 859 

Figure 8–111. Centerline Pressure Contours and Velocity Vectors for Cases A1, A3 and A5

prior to Suppressant Injection ...................................................................................................... 860 

Figure 8–112. Raytracing images of Cases B1 and B2............................................................................. 862 

Figure 8–113. (a) Temporal Evolution of HFC-125 Mass Fraction in the Recirculation Zone

at a Point 0.012 m above the Lower Surface and 0.05 m behind the Rib along the 

Centerline. (b) Suppression Times as a Function of HFC-125 Mole Fraction for Cases 

B1, B2, C1, and C2. ..................................................................................................................... 862 

Figure 8–114. Locations of the Suppressant Nozzles and the Pools in the Nacelle Simulator................. 863 

Figure 8–115. Contour Plots of C2HF5 at 3.0 s after Start of Suppression Injection in Vertical

Planes near Starboard Side near Nacelle Centerline and near Port Side...................................... 864 

Figure 8–116. Simulation Results of Various Injection Periods............................................................... 866

Figure 8–117. Simulation Results Showing the Effect of Nozzles on Agent Distribution....................... 867 

Figure 8–118. Simulated Agent Distribution along the Nacelle Centerline. ............................................ 867 

Figure 8–119. Ground Test Nacelle ‘Iron Bird’ Simulator....................................................................... 873 

Figure 8–120. Drawing of Front Face of Ground Test Nacelle. ............................................................... 874 

Figure 8–121. Transient Bottle Pressure during Discharge for Various Initial Pressures with 

Nozzles Discharging a Total of 3.2 kg of HFC-125. ................................................................... 880 

Figure 8–122. Nacelle Configuration Used in FDS Simulations.............................................................. 883 

Figure 8–123. Nacelle Configuration Used in FPM Simulations. ............................................................ 883 

Figure 8–124. Results of Tests with All Nozzles Used. ........................................................................... 887 

Figure 8–125. Results of Tests with One Nozzle Capped. ....................................................................... 888 

Figure 8–126. Extinguishment of Heptane Pool Fires by Uncharged Water Mist. .................................. 892 

Figure 8–127. Schematic Sketch of Fire Test Chamber ........................................................................... 895 
List of Figures xxxix

Figure 8–128. Electron Induction Electrode. ............................................................................................ 895 

Figure 8–129. Attraction of Charged Droplets to Grounded Metal Screen. ............................................. 896 

Figure 8–130. Motion of Charged Droplets near Fires. ............................................................................ 898 

Figure 8–131. 7N Seven Hollow Cone Nozzle Setup............................................................................... 899 

Figure 8–132. Spray Charging Set-up....................................................................................................... 900 

Figure 8–133. Effect of Center Nozzle Size on 7N Nozzles Water Flux.................................................. 901 

Figure 8–134. Effect of Electrical Charging on Water Flux Distribution of the 7N Nozzles 

with the 0.063 L/min Center Nozzle............................................................................................ 902 

Figure 8–135. Initial Data on Effect of Electrical Charging for a 10 cm Diameter Heptane 

Pool Fire....................................................................................................................................... 903 

Figure 8–136. All Electrical Charging Data for a 10 cm Diameter Heptane Pool Fire. ........................... 904 

Figure 8–137. Schematic of Single Nozzle Electron Emission Electrode. ............................................... 905 

Figure 8–138. Effect of Electrical Charging on Extinguishment for a 5 cm Diameter Heptane 

Pool Fire....................................................................................................................................... 906 

Figure 8–139. AeroChem 5 cm and 10 cm and NMERI 5 cm Heptane Extinguishment Data................. 907 

Figure 8–140. Experimental Setup for Testing the Relative Effectiveness of Fire 

Extinguishing Agents................................................................................................................... 911 

Figure 8–141. Experimental Setup for Testing Agents Against an Obstructed Flame. ............................ 912 

Figure 8–142. Extinction of a Candle Flame by CO2. .............................................................................. 914 

Figure 8–143. Extinction of a Candle Flame by Halon 1211. .................................................................. 914 

Figure 9–1. Typical Powder Panel Arrangements. ................................................................................... 928 

Figure 9–2. Experimental Test Device and Powder Collection Methods................................................. 935 

Figure 9–3. AVSF Range A Light-gas Gun.............................................................................................. 936 

Figure 9–4. Test Example of Significant Panel Fracture and Material Loss. ........................................... 941 

Figure 9–5. Test Example of Effective Powder Release and Dispersion.................................................. 941 

Figure 9–6. Effect on Powder Panel Fracture Area of Standard Design Features and Enhanced 

Designs......................................................................................................................................... 942 

Figure 9–7. Effect on Powder Delivery of Standard Design Features and Enhanced Designs................. 943 

Figure 9–8. Effect on Powder Dispersion of Standard Design Features and Enhanced 

Designs......................................................................................................................................... 943 

Figure 9–9. JTCG/AS Test Article. .......................................................................................................... 946 

Figure 9–10. Schematic of the FAA Test Article. .................................................................................... 946 

Figure 9–11. Enhanced Powder Panel Fire Mitigation Capability. .......................................................... 947 

Figure 9–12. Comparison of Commercial and Enhanced Powder Panel Agent Release in 

JTCG/AS Dry Bay Fire Extinguishing Testing. .......................................................................... 948 
xl List of Figures 

Figure 9–13. Entire Contents of Enhanced Powder Panel Released During FAA Test in

Which the Fire Was Prevented. ................................................................................................... 948 

Figure 9–14. Enhanced Powder Panel Mass Reduction............................................................................ 952 

Figure 9–15. Enhanced Powder Panel Thickness Reduction.................................................................... 953 

Figure 9–16. Comparison of Enhanced and Commercial Panel Powder Released................................... 953 

Figure 9–17. Comparison of Enhanced and Commercial Panel Percent Powder Released...................... 954 

Figure 9–18. Comparison of Enhanced and Commercial Panel Front Face Area Removal. .................... 954 

Figure 9–19. Range 2 at the WPAFB Aerospace Vehicle Survivability Facility. .................................... 956 

Figure 9–20. Test Article. ......................................................................................................................... 956 

Figure 9–21. Schematic of Test Article .................................................................................................... 957 

Figure 9–22. Test Article Setup in Range 2.............................................................................................. 958 

Figure 9–23. 12.7 mm API Type B-32 Projectile Description. ................................................................ 959 

Figure 9–24. Post-Test Damage Image of EPP-03 Commercial Powder Panel........................................ 961 

Figure 9–25. Post-Test Damage Image of EPP-04 Enhanced Powder Panel............................................ 962 

Figure 9–26. Post-Test Damage Image of EPP-05 Enhanced Powder Panel............................................ 963 

Figure 9–27. Powder Suspension in the Dry Bay Well After the Test. .................................................... 964 

Figure 9–28. Powder Dispersion on Striker Plate and Side Lexan Panel. ................................................ 964 

Figure 9–29. Post-Test Damage Image of EPP-06 Enhanced Powder Panel............................................ 965 

Figure 9–30. Post-Test Damage Image of EPP-07 Enhanced Powder Panel............................................ 965 

Figure 9–31. Post-Test Damage Image of EPP-08 Enhanced Powder Panel............................................ 963 

Figure 9–32. Powder Evident in Dry Bay More Than 5 min after EPP-09 Test. ..................................... 967 

Figure 9–33. Post-Test Damage Image of EPP-09 Enhanced Powder Panel............................................ 967 

Figure 9–34. NAWS-China Lake Propellant Burn Rate Apparatus.......................................................... 978 

Figure 9–35. Aerojet Fire Test Fixture (FTF)........................................................................................... 979 

Figure 9–36. Photograph of Fire Test Fixture........................................................................................... 979 

Figure 9–37. FTF Test Facility Schematic................................................................................................ 980 

Figure 9–38. Fire Test Fixture Operational Configurations...................................................................... 981 

Figure 9–39. Aerojet Slow Discharge Solid Propellant Gas Generator Test Unit.................................... 983 

Figure 9–40. Cutaway of Aerojet Slow Discharge Solid Propellant Gas Generator Test Unit. ............... 984 

Figure 9–41. Aerojet Reusable Rapid Discharge Solid Propellant Fire Extinguisher Unit. ..................... 985 

Figure 9–42. Arrangement of a Typical Hybrid Fire Extinguisher........................................................... 985 

Figure 9–43. Consecutive Frames during SPGG Suppression of a Fire in the FTF. ................................ 986 

Figure 9–44. SPGG Installed in Sponson Test Article for Live-fire Demonstration................................ 987 

Figure 9–45. SPGGs Installed in Mid-wing Test Article for Live-fire Demonstration. ........................... 987 

Figure 9–46. Typical Setup of Preliminary Vise Shot for Hybrid Extinguisher....................................... 988 
List of Figures xli

Figure 9–47. Chamber Pressure for Different Propellant Surface Areas (CA-04). .................................. 990 

Figure 9–48. Housing Temperatures for Different Propellant Surface Areas (CA-04). ........................... 990 

Figure 9–49. High-nitrogen Fuels Used in China Lake/Aerojet Propellant Development. ...................... 993 

Figure 9–50. Synthetic Route to BTATZ.................................................................................................. 995 

Figure 9–51. Temperature Dependence of Propellant Burn Rates for Different 

FS01-40/additive Combinations. ................................................................................................. 998 

Figure 9–52. Effect of Coolant Percentage on Burning Rate (in./s) and Adiabatic Temperature 

of High Nitrogen Propellants Listed in Table 9–18..................................................................... 999 

Figure 9–53. Representative SPGG Pressure-time Curve Obtained during Delivery of 

Candidate Chemically Active Agents........................................................................................ 1004 

Figure 9–54. Representative P-t Curve for SPGG Chamber Pressure. ................................................... 1009 

Figure 9–55. Representative P-t Curve for Fire Test Fixture Pressure before, during, and after 

SPGG discharge......................................................................................................................... 1009 

Figure 9–56. Threshold Mass of Inert Propellant Plus Potassium Compound for Suppression 

in the FTF................................................................................................................................... 1010 

Figure 9–57. Schematic of Hybrid Extinguisher Workhorse Hardware Configuration.......................... 1012 

Figure 9–58. Mounting Configuration of Multiple Hybrid Extinguishers Used to Bracket 

Threshold Levels........................................................................................................................ 1012 

Figure 9–59. Effectiveness of Various Hybrid Extinguisher Propellant/fluid Combinations................. 1017 

Figure 9–60. Relative Effectiveness of Various SPGG Fire Extinguishers over the Span of the 

NGP Research............................................................................................................................ 1020 

Figure 9–61. Evolution of SPGG Fire Suppression Application Technologies...................................... 1020 

Figure 10–1. Typical Cargo Aircraft Engine Nacelle Fire Protection System Location (Wing 

Leading Edge)............................................................................................................................ 1030 

Figure 10–2. Close-up of Typical Engine Nacelle Fire Protection System Bottle. ................................ 1030 

Figure 10–3. Typical Cargo Aircraft Engine Nacelle Fire Suppressant Storage and 

Distribution System (Wing Leading Edge)................................................................................ 1031 

Figure 10–4. Typical Auxiliary Power Unit Fire Protection System Location....................................... 1034 

Figure 10–5. Typical General Location of Fighter Aircraft Fire Extinguisher Bottle. ........................... 1034 

Figure 10–6. Schematic of Typical Fighter Aircraft Engine Bay. .......................................................... 1035 

Figure 10–7. Typical Fighter Aircraft Fire Suppression System Installation. ........................................ 1035 

Figure 10–8. Typical General Location of Rotary-Wing Aircraft Fire Extinguisher Bottles. ................ 1039 

Figure 10–9. Typical Future Fighter Aircraft Agent Distribution System.............................................. 1049 

Figure 10–10. F-22 Factor of Safety Data. ............................................................................................. 1070 

Figure 10–11. Legacy and Future Cargo Aircraft Net Costs vs. System Effectiveness for 

Halon 1301................................................................................................................................. 1074 
xlii List of Figures 

Figure 10–12. Legacy Cargo Aircraft Net Costs vs. System Effectiveness for

HFC-125. ................................................................................................................................... 1074 

Figure 10–13. Future Cargo Aircraft Net Costs vs. System Effectiveness for 

HFC-125. ................................................................................................................................... 1075 

Figure 10–14. Legacy and Future Cargo Aircraft Cost Savings vs. System Effectiveness. ................... 1075 

Figure 10–15. Legacy Fighter Aircraft Net Costs vs. System Effectiveness.......................................... 1077 

Figure 10–16. Future Fighter Aircraft Net Costs vs. System Effectiveness. .......................................... 1077 

Figure 10–17. Legacy and Future Fighter Aircraft Cost Savings vs. System Effectiveness. ................. 1078 

Figure 10–18. Legacy Rotary-wing Aircraft Net Costs vs. System Effectiveness for Halon 

1301. .......................................................................................................................................... 1079 

Figure 10–19. Legacy Rotary-Wing Aircraft Net Costs vs. System Effectiveness for HFC125. ............................................................................................................................................ 1080 

Figure 10–20. Future Rotary-Wing Aircraft Net Costs vs. System Effectiveness for Halon 

1301. .......................................................................................................................................... 1080 

Figure 10–21. Future Rotary-Wing Aircraft Net Costs vs. System Effectiveness for HFC-125............ 1081 

Figure 10–22. Legacy and Future Rotary-Wing Aircraft Cost Savings vs. System 

Effectiveness.............................................................................................................................. 1081 

Figure 11–1. AENTF Primary Mechanical Components........................................................................ 1107 

Figure 11–2. Photograph of Universal Test Fixture................................................................................ 1107 

Figure 11–3. Cutaway View of the Engine Core inside the Nacelle Fixture .......................................... 1108 

Figure 11–4. Vertical Extinguisher Unit Attached to the Nacelle Fixture.............................................. 1108 

Figure 11–5. AENTF Control Room. ..................................................................................................... 1109 

Figure 11–6. Semi-Transparent View of Components in Fire Section of the Test Fixture. ................... 1110 

Figure 11–7. Pool Fire Pan in Nacelle. ................................................................................................... 1110 

Figure 11–8. Schematic of Spray Fire Vicinity. ..................................................................................... 1111 

Figure 11–9. 7.6 cm Ribs Mounted on the Underside of the Nacelle and the Engine Core. .................. 1111 

Figure 11–10. Discharge “T” and with Nozzles Added for Phase II . .................................................... 1119 

Figure 11–11. Halonyzer Probe Mounting in Flame Region.................................................................. 1120 

Figure 11–12. Halonyzer Probes in Nacelle Fixture............................................................................... 1120 

Figure 11–13. Phase II Nacelle Concentration Measurement Quadrants. .............................................. 1123 

Figure 11–14. Layout for Multi-Port Discharge. .................................................................................... 1123 

Figure 11–15. Variation of Moles of Injected Chemical per Fire Zone Volume Percent with

Relative Air Temperature. ......................................................................................................... 1127 

Figure 11–16. Variation of Concentration Standard Deviation with Number of Discharge 

Sites............................................................................................................................................ 1127 

Figure 11–17. Variation of Concentration Standard Deviation with Rib Height.................................... 1128 
List of Figures xliii

Figure 11–18. Reduction in Moles/Concentration with Increasing τ, Residence Time.......................... 1129 

Figure 11–19. Effect of Agent Type and Relative Temperature on Extinguishing 

Concentration............................................................................................................................. 1130 

Figure 11–20. Notional Graphs of Concentration in the Free Stream and Recirculation Zone. ............. 1133 

Figure 11–21. Sample Halonyzer Traces................................................................................................ 1134 

Figure 11–22. Influence of Flame Stabilizing Rib Height on Value of τ. .............................................. 1136 

Figure 11–23. Influence of Fire Type on Value of τ............................................................................... 1136 

Figure 11–24. Influence of Agent and Air Temperature on Value of τ. ................................................. 1137 

Figure 11–25. Variability in Peak Concentration Required Due to Extinguisher Flow. ........................ 1140 

Figure 11–26. Variability in Peak Concentration Required Due to Rib Height. .................................... 1141 
xliv List of Figures 

Page intentionally left blank 
LIST OF TABLES

Table 1–1. Flame Suppression by Halon 1301 and Other Chemicals .............................................5 

Table 1–2. Use of Halon 1301 in Fielded Weapons Systems..........................................................7 

Table 2–1. Evolution of Aircraft Vulnerability Based on Live Fire Test Vulnerability 

Assessments (API Threats)................................................................................................22 

Table 2–2 Tabulation of Aircraft Fire Types.................................................................................42 

Table 2–3. Number of Mishaps and Incidents...............................................................................60 

Table 2–4. Percentage of Fire Mishaps and Incidents Occurring in Geographic Cold 

or Severe-Cold Environments............................................................................................60 

Table 2–5. Comparison of Modeled vs. Measured Nacelle Air Temperatures .............................68 

Table 2–6. Estimate of Rate of Occurrence of Aircraft Lost Due to Failure to 

Extinguish a Nacelle Fire, Any Time ................................................................................72 

Table 2–7. Estimate of Rate of Occurrence of Aircraft Lost Due to Failure to 

Extinguish a Nacelle Fire, Any Time ................................................................................72 

Table 2–8. Estimate of Rate of Occurrence of Aircraft Lost Due to Failure to 

Extinguish a Nacelle Fire in a Climatic Extreme...............................................................73 

Table 2–9. Estimate of Rate of Occurrence of Aircraft Lost Due to Failure to 

Extinguish a Nacelle Fire in a Climatic Extreme...............................................................73 

Table 2–10. Fire Suppressants on DoD Aircraft............................................................................87 

Table 2–11. Most Significant Fire Suppression Parameters Identified During Phase 1................93 

Table 2–12. Halon Alternative Fire Suppressants Identified for Phase 2 Evaluation. ..................94 

Table 2–13. Most Significant Fire Suppression Parameters Identified During Phase 2................94 

Table 2–14. Fire Suppression Parameters in Design Guidance Developed from Phase 3. ...........95 

Table 2–15. Minimum Fire Suppressant Quantities from F-22 Main Landing Gear 

Dry Bay Live Fire Testing, 150-grain Fragment Threat and Jet Fuel Except 

Where Noted. ...................................................................................................................103 

Table 3–1. Agents Tested. ...........................................................................................................125 

Table 3–2. Cup Burner Extinction Concentrations......................................................................137 

Table 3–3. Catalytic Efficiency of Different Metals in Promoting Radical 

Recombination. ................................................................................................................149 

Table 3–4. Metals Which Have Shown Flame Inhibiting Properties. .........................................155 
xlvi List of Tables 

Table 3–5. Inhibitor Concentrations (μL/L) and Uncertainty (± μL/L) at Flame 

Extinction.........................................................................................................................161 

Table 3–6. Uninhibited Laminar Burning Velocities SL and Adiabatic Flame 

Temperatures TAFT from 1-D Planar Numerical Calculations, Together with 

the Average Burning Velocity Measured in the Bunsen-type Flames.............................180 

Table 3–7. Reaction Rate Data for Tin Inhibition of Premixed Methane-air Flames..................182 

Table 3–8. Thermodynamic Properties of Tin- and Manganese-containing Species 

(298 K).............................................................................................................................183 

Table 3–9. Reaction Rate Data for Manganese Inhibition of Premixed Methane-air 

Flames..............................................................................................................................184 

Table 3–10. Summary of the Fe and Na Mass Loadings in Unheated and Heated 

Particles............................................................................................................................203 

Table 3–11. Components of Metallic Complexes........................................................................213 

Table 3–12. Current State of Knowledge Relevant to Inhibition Potential of Metals, 

and Loss of Effectiveness due to Condensation ..............................................................233 

Table 3–13. Flame Conditions.....................................................................................................256 

Table 3–14. Probe Orifice Diameters Used in Specific Experiments..........................................269 

Table 3–15. FTIR Detection Limits and Wavenumber Ranges...................................................270 

Table 3–16. Operating Conditions...............................................................................................272 

Table 3–17. Inhibitor Concentrations and Uncertainty at Flame Extinction...............................285 

Table 3–18. Measured OH Profile Widths for the Uninhibited Flame and Inhibited 

Flames at 50 % of the Inhibitor Extinction Concentrations.............................................287 

Table 3–19. Comparison of Calculated Burning Velocities. .......................................................297 

Table 3–20. Kinetic Mechanisms for Suppressants.....................................................................302 

Table 3–21. Efficiencies and Sensitivities to Bond Energies of Catalytic Cycles.......................306 

Table 3–22. Input Parameters and Calculated Temperatures and Flame Speeds. .......................310 

Table 4–1. Mean Diameter Definitions, Symbols, and Notations used to Describe 

Aerosol Size Distributions. ..............................................................................................348 

Table 4–2. Thermodynamic Quantities for Physical Suppressants Compared to 

CF3Br. ..............................................................................................................................368 

Table 4–3. Number Density and Droplet Separation Lengths for Some Selected Water 

Mass Fractions. ................................................................................................................374 

Table 4–4. Stokes Number (St) for Different Droplet Sizes for a = 130 s-1.................................376 

Table 4–5. PDPA Derived Diameter Information for the Experimental Mists Studied 

Measured at 2 mm from the Air Tube Exit......................................................................386 
List of Tables xlvii

Table 4–6. Flow and Strain Rate Conditions for Extinction Experiments. .................................398 

Table 4–7. Propane-air Counterflow Non-premixed Flame Extinction Mass 

Concentrations for Powders and Halon 1301. .................................................................401 

Table 4–8. Experimental and Predicted Global Flame Extinction Strain Rates (s-1) for 

Different Droplet Size Distributions and Water Droplet Mass Fraction of 0.01.............420 

Table 4–9. Elemental Composition of Pure Dendrimers and Dendrimer Salt 

Complexes........................................................................................................................431 

Table 4–10. Average Blow-off Velocities for of Various Candidate Agents..............................433 

Table 5–1. Optical Diagnostics for Fire Species. ........................................................................483 

Table 6–1. Calculated Nominal Agent Mass Fractions at Reference Blow-off Air 

Velocity of 30 cm/s..........................................................................................................534 

Table 6–2. Estimated and Reported ODP Values (Relative to CFC-11) for Selected 

Halocarbons. ....................................................................................................................559 

Table 6–3. Atmospheric Lifetimes (years), from Theory and from OH Reactivity 

Measurements, for Selected Molecules. ..........................................................................570 

Table 6–4. Reactions of Phosphates. ...........................................................................................571 

Table 6–5. Estimated Equilibrium Vapor Pressure as a Function of Boiling Point and 

Ambient Temperature. .....................................................................................................573 

Table 6–6. Estimated Maximum Boiling Point That Can Achieve a Given Volume 

Percent of Chemical in Air. .............................................................................................573 

Table 6–7. Cardiac Sensitization Values for Fluorocarbons and Hydrofluorocarbons. ..............580 

Table 6–8. Cardiac Sensitization Values for Br-, Cl-, and I-containing Alkanes........................581 

Table 6–9. Cardiac Sensitization Values for CFCs and HFCs. ...................................................581 

Table 6–10. Availability of QSARs for Various Chemical Classes and Toxic 

Endpoints. ........................................................................................................................583 

Table 6–11. Air Concentration Inducing Cardiac Sensitization in 50 % of Animals..................585 

Table 6–12. Partitioning (KOW) and Arrhythmia Properties of Selected Anesthetics. ................586 

Table 6–13. Comparison of Calculated and Measured Values of Log KOW of Selected 

Halocarbons. ....................................................................................................................588 

Table 6–14. In vitro Cardiac Cell Systems. .................................................................................589 

Table 6–15. Time for Safe Human Exposure at Stated Concentrations for Halon 1301 

and HFC-125....................................................................................................................592 

Table 6–16. Nominal Quantities of Chemicals Needed for Screening Tests. .............................597 
xlviii List of Tables 

Table 7–1. Tropospheric Removal Mechanisms. ........................................................................612 

Table 7–2. NIST List of Recommended Chemical Families (1990). ..........................................615 

Table 7–3. AAWG Preliminary List of Compounds. ..................................................................617 

Table 7–4. TOPKAT Toxicity Predictions. .................................................................................618 

Table 7–5. DEREK Toxicity Predictions.....................................................................................619 

Table 7–6. Acute Inhalation Toxicity Tropodegradable Bromofluoroalkenes............................621 

Table 7–7. Ames Mutagenicity Test Results. ..............................................................................621 

Table 7–8. Chromosomal Aberration Test Results......................................................................621 

Table 7–9. Cardiac Sensitization Testing of Bromofluoropropenes............................................621 

Table 7–10. Anesthesiology Testing of Fluoroalkenes................................................................622 

Table 7–11. Chemical Families Selected for Further Study........................................................625 

Table 7–12. Chemical Families Not Pursued Further..................................................................625 

Table 7–13. Silicon-containing Compounds................................................................................628 

Table 7–14. •OH Rate Constants for Silicon Compounds...........................................................631 

Table 7–15. Tetra(fluoroalkoxy)silanes.......................................................................................633 

Table 7–16. Phosphonitrile Flame Extinguishment.....................................................................637 

Table 7–17. Phosphorus Halide Flame Extinguishment..............................................................638 

Table 7–18. Rate Constants •OH Reactions With Phosphorus Compounds. ..............................640 

Table 7–19. Toxicity Studies of Chlorophosphazenes. ...............................................................642 

Table 7–20. Perfluoroalkyl Sulfur Compounds...........................................................................646 

Table 7–21. Family Types in the DIPPR Database .....................................................................648 

Table 7–22. Compounds with High ∆HTotal (Molar Basis)..........................................................649 

Table 7–23. Compounds with High ∆HTotal (Mass Basis). ...........................................................650 

Table 7–24. Extinguishing Volume Fractions of Inert Gases for CH4/Air Diffusion 

Flames..............................................................................................................................657 

Table 7–25. Extinguishing Volume Fractions of Inert Gases for C3H8/Air Diffusion 

Flames..............................................................................................................................657 

Table 7–26. Tropodegradable Brominated Candidates. ..............................................................659 

Table 7–27 Bromofluoropropenes. ..............................................................................................663 

Table 7–28 Bromofluoropropene Cup Burner Flame Extinguishment Data...............................664 

Table 7–29 Low Boiling Bromofluoroalkene Cup Burner Values..............................................664 

Table 7–30 Phosphorus Compound Toxicity (Safety) Information. ...........................................665 

Table 7–31. FID Extinguishment Estimates of Phosphorus Acids and Esters. ...........................670 
List of Tables xlix

Table 7–32 Properties of Phosphorus-Containing Compounds...................................................671 

Table 7–33. Flame Extinguishment Values for Trimethylphosphite Blends with 

HFCs. ...............................................................................................................................672 

Table 7–34. Enthalpy of Reaction for PF3 + 3 O=CF2 → P(OCF3)3..........................................674 

Table 7–35. Perfluoroalkyl Phosphines. ......................................................................................675

Table 7–36. Amino Fluoroalkylphosphines.................................................................................677 

Table 7–37. Phosphorus-containing Compound Performance. ...................................................679 

Table 7–38. •OH Rate Constants for Nitrogen-containing Compounds......................................681 

Table 7–39. Rate Constants for Reactions of O3 with Amines....................................................681 

Table 7–40. Acute Inhalation Toxicity of Hydrofluoroamines. ..................................................683 

Table 7–41. Toxicity and Safety Information for Selected N, F Compounds. ............................683 

Table 7–42. Fluoroalkylamine Boiling Points.............................................................................684 

Table 7–43. Bromofluoroamine Candidate Compounds. ............................................................685 

Table 7–44. Bromofluoroamine Boiling Points and Flame Suppression Results........................687 

Table 7–45. Rate Constants for Hydrofluoroether Reactions with •OH......................................688 

Table 7–46. Atmospheric Lifetimes for Fluorine-containing Ethers...........................................688 

Table 7–47. Fluoroether Cup Burner Extinguishment Data. .......................................................691 

Table 7–48. Bromofluoroether Cup Burner Testing Summary. ..................................................693 

Table 7–49. Bromofluoropropene Oxide Cup Burner Testing Summary....................................695 

Table 7–50. Bromofluoro Alcohol Boiling Points.......................................................................696 

Table 7–51. Iodoalkane Boiling Points........................................................................................697 

Table 7–52. Compilation of Historic Firefighting Emissions of CF3Br. .....................................698 

Table 7–53. Estimated Ozone Depletion Effects of CF3I for Two Emission Profiles.................699 

Table 8–1. PROFISSY Results for Henry’s Constants................................................................745 

Table 8–2. Operating Condition for Repeatability Tests.............................................................761 

Table 8–3. Matrix of Experimental Runs Conducted. .................................................................775 

Table 8–4. Comparison of Experimental Pressure Drop Values to Literature Values. ...............780 

Table 8–5. Test Matrix from NIST Experiments.........................................................................789 

Table 8–6. Model Geometry and Test Conditions.......................................................................823 

Table 8–7. Summary of Drag Coefficients..................................................................................826 

Table 8–8. Frequency and Strouhal Number Resolution.............................................................827 

Table 8–9. Selected Thermophysical Properties of CF3I and CF3Br...........................................829 
l List of Tables 

Table 8–10. Experimental Matrix................................................................................................832 

Table 8–11. Liquid Fraction of CF3I/N2 Mixture after Isentropic Expansion to 0.101 

MPa..................................................................................................................................835 

Table 8–12. Description of Simulations of Pool Fires Stabilized behind a Backwardsfacing Step. ......................................................................................................................855 

Table 8–13. Pool Characteristics. ................................................................................................868 

Table 8–14. Summary of Test Results with Four Nozzles. .........................................................869 

Table 8–15. Summary of Test Results with Individual Nozzles Capped. ...................................870 

Table 8–16. Comparison of Predicted vs. Measured Pressures and Flows. ................................876 

Table 8–17. Summary of Full-Scale Tests Conducted. ...............................................................881 

Table 8–18. Comparison of Fire Test Results and Pretest Simulations.......................................882 

Table 8–19. Effectiveness of Charged Water Mist Expressed as Percent of Successful 

Pool Fire Extinguishments...............................................................................................893 

Table 8–20. Hollow Cone Nozzle Characteristics.......................................................................894 

Table 8–21. High Flow Capacity Seven Nozzle Assembly.........................................................899 

Table 8–22. Low Flow Capacity Seven Nozzle Assembly..........................................................899 

Table 8–23. Solid Cone Nozzle Characteristics. .........................................................................905 

Table 9–1. Examples of Previously Tested Powder Panel Materials. .........................................933 

Table 9–2. Phase I Powder Panel Configurations Tested............................................................937 

Table 9–3. More Effective Powder Panel Designs in Experimental Testing. .............................939 

Table 9–4. Less Effective Powder Panel Designs in Experimental Testing................................940 

Table 9–5. Phase II Optimization Tests.......................................................................................950 

Table 9–6. Phase II Enhanced Powder Panel Live Fire Demonstration Tests.............................960 

Table 9–7. C-130 Wing Leading Edge Dry Bay Fire Extinguishing System 

Component Mass Estimates.............................................................................................970 

Table 9–8. C-130 Wing Leading Edge Dry Bay Total Fire Extinguishing System

Mass Estimates.................................................................................................................970 

Table 9–9. V-22 Outboard Tip Rib Dry Bay Fire Extinguishing System Component 

Mass Estimates.................................................................................................................971 

Table 9–10. V-22 Outboard Tip Rib Dry Bay Total Fire Extinguishing System Mass 

Estimates..........................................................................................................................971 

Table 9–11. Fire Test Fixture Operating Conditions...................................................................982 

Table 9–12. Comparison of Aerojet FTF to Other Fire Test Fixtures.........................................982 

Table 9–13. Temperature Dependence of Burn Rate for Baseline Propellant, FS-0140.............991 
List of Tables li

Table 9–14. Adiabatic Temperatures of High Nitrogen Propellant Fuels in 

Stoichiometric Mixtures with Sr(NO3)2 Oxidizer............................................................994 

Table 9–15. Adiabatic Temperatures of Oxidizers in Stoichiometric Mixtures with..................996 

Table 9–16. Development Propellant Compositions and Burning Parameters............................997 

Table 9–17. Effect of Different Coolants on Adiabatic Flame Temperature of 5ATSr(NO3)2 Propellant Mixture............................................................................................999 

Table 9–18. High Nitrogen Content Developmental Propellants with MgCO3 Coolant: 

Compositions and Burning Parameters..........................................................................1000 

Table 9–19. Candidate Chemically Active Agents....................................................................1002 

Table 9–20. Summary of SPGG Fire Suppression Testing with Chemically Active 

Agents. ...........................................................................................................................1004 

Table 9–21. Chemically Active Developmental Propellants.....................................................1006 

Table 9–22. Threshold Mass of Propellant and Potassium-based Additive for Fire 

Suppression in the FTF. .................................................................................................1011 

Table 9–23. Properties of Hybrid Fluid Candidates. .................................................................1013 

Table 9–24. Hybrid Extinguisher Fluorocarbon System Data Summary. .................................1014 

Table 9–25. Hybrid Extinguisher Aqueous System Data Summary..........................................1015 

Table 10–1. Properties of Halon 1301 and HFC-125 Used in Life-cycle Costing....................1029 

Table 10–2. Additional Legacy Cargo Aircraft Fire Protection System Information. ..............1031 

Table 10–3. Additional Legacy Fighter Aircraft Fire Suppression System Information ..........1036 

Table 10–4. Legacy Rotary-wing Aircraft Specific Parameters................................................1040 

Table 10–5. Additional Legacy Rotary-wing Aircraft Fire Suppression System 

Information. ...................................................................................................................1041 

Table 10–6. Design Guide Estimates of HFC-125 Concentration and Mass for Future 

Cargo Aircraft Engine Nacelles.....................................................................................1045 

Table 10–7. Design Guide Estimates of HFC-125 Concentration and Mass for Future 

Cargo Aircraft Auxiliary Power Units...........................................................................1046 

Table 10–8. Future Cargo Aircraft Proposed System Estimates. ..............................................1046 

Table 10–9. Future Cargo Aircraft Extinguisher Container and Agent Mass. ..........................1047 

Table 10–10. Future Fighter Aircraft Engine Nacelle Fire Protection System 

Components. ..................................................................................................................1050 

Table 10–11. Fighter Aircraft Fire Suppression System Mass Comparison. ............................1050 

Table 10–12. Future Fighter Aircraft Specific Parameters........................................................1051 

Table 10–13. Estimates of System Parameters for Proposed Future Fighter Aircraft 

System Description. .......................................................................................................1051 
lii List of Tables 

Table 10–14. Future Fighter Aircraft Extinguisher Container and Agent Mass........................1052 

Table 10–15. Future Rotary-wing Aircraft Specific Parameters. ..............................................1053 

Table 10–16. Future Rotary-wing Aircraft Analysis of Increase in Total Mass. ......................1053 

Table 10–17. Comparison of Halon 1301 and HFC-125 System Life-cycle (FY00 to 

FY22) Cost Estimates for Legacy Cargo Aircraft. ........................................................1056 

Table 10–18. Comparison of Halon 1301 and HFC-125 System Life-cycle (FY00 to 

FY28) Cost Estimates for Legacy Fighter Aircraft........................................................1057 

Table 10–19. Comparison of Halon 1301 and HFC-125 System Life-cycle (FY03 to 

FY35) Cost Estimates for Legacy Rotary-wing Aircraft...............................................1058 

Table 10–20. Comparison of Halon 1301 and HFC-125 System Life-cycle (FY00 to 

FY31) Cost Estimates for Future Cargo Aircraft...........................................................1059 

Table 10–21. Comparison of Halon 1301 and HFC-125 System Life-cycle (FY00 to 

FY32) Cost Estimates for Fighter Cargo Aircraft..........................................................1060 

Table 10–22. Comparison of Halon 1301 and HFC-125 System Life-cycle (FY03 to 

FY41) Cost Estimates for Future Rotary-wing Aircraft ................................................1061 

Table 10–23. Detailed Cost Element Structure..........................................................................1062 

Table 10–24. Cargo Aircraft Cost Savings Estimation..............................................................1067 

Table 10–25. Fighter Aircraft Cost Savings Estimation............................................................1067 

Table 10–26. Rotary-wing Aircraft Costs Savings Estimation..................................................1067 

Table 10–27. Estimated Cargo Aircraft System Description.....................................................1069 

Table 10–28. Estimated Fighter Aircraft System Description...................................................1069 

Table 10–29. Estimated Rotary-wing Aircraft System Description. .........................................1070 

Table 10–30. Cargo Aircraft Altered System Description.........................................................1071 

Table 10–31. Fighter Aircraft Altered System Description.......................................................1072 

Table 10–32. Rotary-wing Aircraft Altered System Description. .............................................1072 

Table 10–33. Legacy Cargo Aircraft Net Costs.........................................................................1073 

Table 10–34. Future Cargo Aircraft Net Costs..........................................................................1073 

Table 10–35. Legacy Fighter Aircraft Net Costs.......................................................................1076 

Table 10–36. Future Fighter Aircraft Net Costs........................................................................1076 

Table 10–37. Legacy Rotary-wing Aircraft Net Costs..............................................................1078 

Table 10–38. Future Rotary-wing Aircraft Net Costs ...............................................................1079 

Table 11–1. Local Conditions Fire Test (Phase I) Matrix. ........................................................1121 

Table 11–2. Factors and Values for Phase I Fire Test Matrix. ..................................................1121 

Table 11–3. Extinguishant Dispersion Optimization (Phase II) Test Matrix. ...........................1124 
List of Tables liii

Table 11–4. Factors and Values for Phase II Agent Distribution Test Matrix. .........................1124 

Table 11–5. Phase I Summary Data...........................................................................................1126

Table 11–6. Phase II Summary Data. ........................................................................................1126 

Table 11–7. Values of X¥ and τ from Prior Experimentation. ..................................................1131 

Table 11–8. Rank Order of τ Values in All Test Run Conditions for Both Mixing 

Models............................................................................................................................1135 

Table 11–9. Flame Extinguishment Concentrations. (% by Volume).......................................1137 

Table 11–10. Calculated Peak Concentrations under Fire Extinguishment Conditions............1139 

Table 11–11. Results of Fire Experiments with HFC-227ea and 2-bromo-3,3,3-

trifluoropropene. ............................................................................................................1141 
liv List of Tables 

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