NIST Technical Note 1440 Characteristics and Identification of Super- Effective Thermal Fire-Extinguishing Agents: Final Report, NGP Project 4C/1/890 William M. Pitts Jiann C. Yang Rodney A. Bryant Linda G. Blevins Marcia L. Huber NIST Technical Note 1440 Characteristics and Identification of Super- Effective Thermal Fire-Extinguishing Agents: Final Report, NGP Project 4C/1/890 William M. Pitts Jiann C. Yang Rodney A. Bryant Linda G. Blevins Building and Fire Research Laboratory Marcia L. Huber Chemical Science and Technology Laboratory June 2001 Issued July 2006 U.S. Department of Commerce Donald L. Evans, Secretary National Institute of Standards and Technology Dr. Karen H. Brown, Acting Director Certain commercial entities, equipment, or materials may be 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, nor is it intended to imply that the entities, materials, or equipment are necessarily the best available for the purpose. National Institute of Standards and Technology Technical Note 1440 Natl. Inst. Stand. Technol. Tech. Note 1440, 138 pages (July 2006) CODEN: NSPUE2 TABLE OF CONTENTS LIST OF TABLES............................................................................................................................................ iii LISTS OF FIGURES ......................................................................................................................................... v EXECUTIVE SUMMARY .............................................................................................................................. xi I. INTRODUCTION................................................................................................................................... 1 II. IDENTIFICATION AND TESTING OF POTENTIAL HIGHLY EFFECTIVE THERMAL AGENTS ................................................................................................................................................. 2 A. Screening Based on Thermophysical Properties............................................................................... 2 B. Experimental Testing of Lactic Acid and HFE7100....................................................................... 11 1. Lactic Acid ............................................................................................................................... 11 a) Estimation of the latent heat of vaporization for lactic acid/water mixtures ..................... 11 b) Experimental system.......................................................................................................... 13 c) Experimental results for lactic acid/water mixture fire suppression effectiveness ............ 14 2. HFE7100 .................................................................................................................................. 16 a) Testing of HFE7100 using the Dispersed Liquid Agent Fire Suppression Screen facility ................................................................................................................................ 16 b) Testing of HFE7100 using the Transient Application Recirculating Pool Fire facility..... 16 III. DETAILED CHEMICAL-KINETIC MODELING AND EXPERIMENTAL INVESTIGATIONS OF THEMAL AGENT FLAME EXTINGUISHMENT....................................................................... 19 A. Introduction..................................................................................................................................... 19 B. Introduction to Detailed Chemical-Kinetic Modeling of Diffusion Flames ................................... 22 C. Modeling Approach ........................................................................................................................ 27 1. CHEMKIN III and OPPDIF..................................................................................................... 27 2. Detailed Chemical-Kinetic Mechanism for Methane............................................................... 27 3. Detailed Chemical-Kinetic Mechanism for Propane................................................................ 27 4. Modeling Details ...................................................................................................................... 28 D. Model Results for Methane and Propane Flames Burning in Air................................................... 29 E. Extinction and Extinguishment of Methane and Propane Diffusion Flames by Nitrogen.............. 38 1. Experimental Systems for Measuring Extinguishing Concentrations of Gaseous Thermal Agents....................................................................................................................................... 40 a) Modified Dispersed Liquid Agent Fire Suppression Screen System (Tsuji Burner)......... 40 b) NIST Coflow Diffusion Flame Burner (Santoro Burner) .................................................. 41 2. Results for Thermal Agent Extinction of Methane and Propane Diffusion Flames Burning on Tsuji and Santoro Burners................................................................................................... 43 a) Tsuji Burner ....................................................................................................................... 43 b) Santoro Burner................................................................................................................... 44 3. Modeling of Extinction and Extinguishment of Methane and Propane Flames by Nitrogen... 51 F. Effects of Argon Addition on Extinction and Extinguishment of Methane Diffusion Flames Burning in Argon “Air” .................................................................................................................. 56 G. Extinguishment of Methane and Propane Diffusion Flames by Carbon Dioxide, Argon, Helium and Water Vapor............................................................................................................................. 57 H. Effects of Dilution and Heat Extraction Location Relative to the Flame Front on Extinction and Extinguishment of Diffusion Flames ..............................................................................................70 I. Prediction of Extinguishing Concentration for HFE7100............................................................... 80 IV. SURFACE COOLING .......................................................................................................................... 81 A. Introduction..................................................................................................................................... 81 i B. Evaporation of Liquid Droplets ...................................................................................................... 83 C. Spray Cooling ................................................................................................................................. 86 D. Convective Regime......................................................................................................................... 87 E. Nucleate Boiling Regime................................................................................................................ 87 F. Critical Heat Flux............................................................................................................................ 88 G. Transition and Film Boiling Regimes.............................................................................................89 H. Summary......................................................................................................................................... 90 V. DISCUSSION........................................................................................................................................ 91 A. Liquid HFE7100 As a Potential Fire-Fighting Agent and Liquid Agent Effectiveness ................. 91 B. Conclusions from Detailed Chemical-Kinetic Modeling of Thermal Agent Effects...................... 93 VI. RECOMMENDATIONS FOR ADDITIONAL STUDY...................................................................... 96 VII. ACKNOWLEDGEMENTS .................................................................................................................. 96 VIII. APPENDIX A--DETAILED CHEMICAL-KINETIC MECHANISM FOR PROPANE COMBUSITON..................................................................................................................................... 97 IX. APPENDIX B—ADDITIONAL DETAILS CONCERNING THE COFLOW DIFFUSION FLAME EXPERIMENT ..................................................................................................................... 109 A. Mass-Flow Controllers and Their Calibration .............................................................................. 109 B. Detailed Description of Gas Flow Calculations............................................................................ 109 C. Uncertainty Analysis..................................................................................................................... 113 X. REFERENCES.................................................................................................................................... 115 ii LIST OF TABLES Table 1. Family Types in the DIPPR Database...................................................................................................2 Table 2. Results of Search for Compounds with High Heat of Vaporization